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41.
A. Baldan Adriaan M. H. van der Veen Daniela Prauß Angelika Recknagel N. Boley Steve Evans Derek Woods 《Accreditation and quality assurance》2001,6(4-5):164-167
Many proficiency tests are operated with a consensus value derived from the participants’ results. Apart from technical issues,
one of the reasons often mentioned is that proficiency tests operated with consensus values would be cheaper than those using
reference values obtained from a priori characterisation measurements. The economy of a proficiency test must of course be balanced by the need of the participants,
and the quality of the comparison in general. The proficiency tests selected in this study had both a reference value and
a consensus value, one of which was used for assessing the performance of the participating laboratories. In this work, both
a technical and an economical assessment of how the comparisons were operated is made. From the evaluation, it follows that
usually the use of consensus values does not necessarily reduce the costs of a proficiency test. However, frequently it may
be observed that the quality of the assessment of the laboratories is better with a reference value.
Received: 11 October 2000 Accepted: 3 January 2001 相似文献
42.
Diane S. Abou Nikki A. Thiele Nicholas T. Gutsche Alexandria Villmer Hanwen Zhang Joshua J. Woods Kwamena E. Baidoo Freddy E. Escorcia Justin J. Wilson Daniel L. J. Thorek 《Chemical science》2021,12(10):3733
Targeted alpha therapy is an emerging strategy for the treatment of disseminated cancer. [223Ra]RaCl2 is the only clinically approved alpha particle-emitting drug, and it is used to treat castrate-resistant prostate cancer bone metastases, to which [223Ra]Ra2+ localizes. To specifically direct [223Ra]Ra2+ to non-osseous disease sites, chelation and conjugation to a cancer-targeting moiety is necessary. Although previous efforts to stably chelate [223Ra]Ra2+ for this purpose have had limited success, here we report a biologically stable radiocomplex with the 18-membered macrocyclic chelator macropa. Quantitative labeling of macropa with [223Ra]Ra2+ was accomplished within 5 min at room temperature with a radiolabeling efficiency of >95%, representing a significant advancement over conventional chelators such as DOTA and EDTA, which were unable to completely complex [223Ra]Ra2+ under these conditions. [223Ra][Ra(macropa)] was highly stable in human serum and exhibited dramatically reduced bone and spleen uptake in mice in comparison to bone-targeted [223Ra]RaCl2, signifying that [223Ra][Ra(macropa)] remains intact in vivo. Upon conjugation of macropa to a single amino acid β-alanine as well as to the prostate-specific membrane antigen-targeting peptide DUPA, both constructs retained high affinity for 223Ra, complexing >95% of Ra2+ in solution. Furthermore, [223Ra][Ra(macropa-β-alanine)] was rapidly cleared from mice and showed low 223Ra bone absorption, indicating that this conjugate is stable under biological conditions. Unexpectedly, this stability was lost upon conjugation of macropa to DUPA, which suggests a role of targeting vectors in complex stability in vivo for this system. Nonetheless, our successful demonstration of efficient radiolabeling of the β-alanine conjugate with 223Ra and its subsequent stability in vivo establishes for the first time the possibility of delivering [223Ra]Ra2+ to metastases outside of the bone using functionalized chelators, marking a significant expansion of the therapeutic utility of this radiometal in the clinic.The therapeutic alpha-emitter 223Ra can be stably complexed in vivo, creating opportunities for the development of targeted radiopharmaceutical agents with this radionuclide. 相似文献
43.
R. C. Woods A. W. Kugel P. I. Karassikund W. I. Dobatkin P. P. Budnikow und S. S. Shukowskaja 《Fresenius' Journal of Analytical Chemistry》1942,123(7-8):312-313
Ohne Zusammenfassung 相似文献
44.
Woods 《Fresenius' Journal of Analytical Chemistry》1863,2(1):425-426
Ohne Zusammenfassung 相似文献
45.
The generation of slugs was studied for air–water flow in horizontal 0.0763 m and 0.095 m pipes. The emphasis was on high liquid rates (uLS ? 0.5 m/s) for which slugs are formed close to the entry and the time intervals between slugs are stochastic. A “fully developed” slug flow is defined as consisting of slugs with different sizes interspersed in a stratified flow with a height slightly larger than the height, h0, needed for a slug to be stable. Properties of this “fully developed” pattern are discussed. A correlation for the frequency of slugging is suggested, which describes our data as well as the data from other laboratories for a wide range of conditions. The possibility is explored that there is a further increase of slug length beyond the “fully developed” condition because slugs slowly overtake one another. 相似文献
46.
Nuclear fuel can be fabricated using powder-metallurgy processes by compacting uranium-oxide powder with aluminum powder to
form a cermet and then extruding the cermet to form fuel tubes. This method of production allows greater control of uranium-oxide
particle size and distribution in the tube, making the production of fuel with greater concentrations of uranium oxide possible,
and thus decreasing the volume of radioactive waste remaining after the fuel is spent. As the concentration of uranium oxide
increases, however, there is an increase in failures during extrusion. To address this problem, an experimental procedure
was developed to examine the response of powder aluminum, a material with a structure similar to that of the cermet fuel,
to biaxial loadings such as those experienced during extrusion. Biaxial loadings can be varied from pure shear to simple tension
or compression, or to combinations of these loadings in a numerically controlled ‘tension-torsion’ testing machine. Data obtained
using this system were used to develop a model for the post-yield behavior in extruded powder aluminum which includes information
derived both from the macroscopic stress-strain behavior of 1100 aluminum and extruded powder aluminum and from the observed
microscopic structure of the extruded powder aluminum.
This paper describes the development of the experimental system and shows the different biaxial mechanical behavior of the
two materials. Test fixtures were developed and software was written to control constant strain-rate tension, compression,
torsion, combined tension-torsion, and combined compression-torsion tests performed using a computer-controlled MTS biaxial
testing machine. Extruded powder aluminum and 1100 aluminum specimens were tested at 427°C, the powder-aluminum extrusion
temperature, under those loading conditions. Each specimen was subjected to only one loading cycle. Data were recorded during
loading only. Tested specimens were also sectioned and examined microscopically. 相似文献
47.
Gordon T. Woods 《Foundations of Chemistry》2010,12(3):171-186
This article traces the life of Russian chemist Dmitri Mendeleev from childhood in Siberia, through education and training to become the first formulator of the Periodic Table, the logo of chemistry. His unique contribution is described and analysed; what factors helped him be the first formulator? What did he do after making his most famous discovery? In addition the article peeps into his personal life, his dealings with his family and the authorities. Finally we look at honours he received in later life. 相似文献
48.
Arijit Das Eric Soehnlen Stephan Woods Ravi Hegde Amanda Henry Arne Gericke Soumitra Basu 《Journal of nanoparticle research》2011,13(12):6283-6290
We report a novel gold nanobioconjugate system that achieves targeted delivery of the small molecule drug doxorubicin to endothelial
cells using anti-VEGFR-2 antibody conjugated gold nanoparticles (GNPs). The reported nanobioconjugate system combines the
inherent ability of GNPs to undergo high levels of derivatization with the precision of antibody recognition of a cell surface
antigen. Transmission electron microscopy (TEM) and surface-enhanced Raman spectroscopy (SERS) confirmed intracellular presence
of the GNPs. Using a VEGFR-2 expressing cell line and a cell line that is negative for the receptor, in combination with competition
assay we established the cell specific targeted delivery of the nanobioconjugate. The nanobioconjugate system described here
may have potential drug delivery applications for antiangiogenic cancer therapy. 相似文献
49.
50.
F. Vanderbist P. Leleux C. Angulo E. Casarejos M. Couder M. Loiselet G. Ryckewaert P. Descouvemont M. Aliotta T. Davinson Z. Liu P. J. Woods 《The European Physical Journal A - Hadrons and Nuclei》2006,27(2):183-186
The 15O(α,α)15O elastic scattering is investigated using a 15O radioactive beam and a He gas cell limited by Mylar windows. The width of a 19Ne state at an excitation energy of 5.35MeV is measured as Γα = 3.2±1.6keV, in agreement with charge symmetry estimate. 相似文献