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111.
Ghislain Fourier Nathan Manning Prasad Senesi 《Abhandlungen aus dem Mathematischen Seminar der Universit?t Hamburg》2013,83(1):53-82
We define global Weyl modules for twisted loop algebras and analyze their highest weight spaces, which are in fact isomorphic to Laurent polynomial rings in finitely many variables. We are able to show that the global Weyl module is a free module of finite rank over these rings. Furthermore we prove, that there exist injective maps from the global Weyl modules for twisted loop algebras into a direct sum of global Weyl modules for untwisted loop algebras. Relations between local Weyl modules for twisted and untwisted generalized current algebras are known; we provide for the first time a relation on global Weyl modules. 相似文献
112.
Thomas E. Yankeelov Todd E. Peterson Richard G. Abramson David Garcia-Izquierdo Lori R. Arlinghaus Xia Li Nkiruka C. Atuegwu Ciprian Catana H. Charles Manning Zahi A. Fayad John C. Gore 《Magnetic resonance imaging》2012
With the recent development of integrated positron emission tomography–magnetic resonance imaging (PET–MRI) scanners, new possibilities for quantitative molecular imaging of cancer are realized. However, the practical advantages and potential clinical benefits of the ability to record PET and MRI data simultaneously must be balanced against the substantial costs and other requirements of such devices. In this review, we highlight several of the key areas where integrated PET–MRI measurements, obtained simultaneously, are anticipated to have a significant impact on clinical and/or research studies. These areas include the use of MR-based motion corrections and/or a priori anatomical information for improved reconstruction of PET data, improved arterial input function characterization for PET kinetic modeling, the use of dual-modality contrast agents, and patient comfort and practical convenience. For widespread acceptance, a compelling case could be made if the combination of quantitative MRI and specific PET biomarkers significantly improves our ability to assess tumor status and response to therapy, and some likely candidates are now emerging. We consider the relative advantages and disadvantages afforded by PET–MRI and summarize current opinions and evidence as to the likely value of PET–MRI in the management of cancer. 相似文献
113.
Jovilynn T. Olegario Nay Yee Marissa Miller John Sczepaniak Bruce Manning 《Journal of nanoparticle research》2010,12(6):2057-2068
The reaction of selenate (Se(VI)) with zerovalent iron nanoparticles (nano Fe0) was studied using both conventional batch equilibrium and X-ray spectroscopic techniques. Nano Fe0 has a high uptake capacity for removal of dissolved Se(VI) reaching concentrations as high as 0.10 Se:Fe molar ratio in the solid product mixture. Kinetic studies of the Se(VI) uptake reaction in batch experiments showed an initial reaction rate (0–30 min) of 0.0364 min?1 which was four times greater than conventional Fe0 powder. Analysis of the oxidation state of Se in the solid products by X-ray absorption near edge structure (XANES) spectroscopy showed evidence for the reduction of Se(VI) to insoluble selenide (Se(-II)) species. Structural analysis of the product by extended X-ray absorption fine structure (EXAFS) spectroscopy suggested that Se(-II) was associated with nano Fe0 oxidation products as a poorly ordered iron selenide (FeSe) compound. The fitted first shell Se–Fe interatomic distance of 2.402 (±0.004) Å matched closely with previous studies of the products of Se(IV)-treated Fe(II)-clays and zero-valent iron/iron carbide (Fe/Fe3C). The poorly ordered FeSe product was associated with Fe0 corrosion product phases such as crystalline magnetite (Fe3O4) and Fe(III) oxyhydroxide. The results of this investigation suggest that nano Fe0 is a strong reducing agent capable of efficient reduction of soluble Se oxyanions to insoluble Se(-II). 相似文献
114.
G. S. Manning 《The European physical journal. E, Soft matter》2009,30(4):411-415
The low-field transverse polarizability of the counterions condensed on an isolated charged rod is small. We show that it
can be much larger if the rod is a member of an assembly of aligned rods. The polarization free energy of the assembly of
rods in a transverse field is then similar to its polarization free energy in a field parallel to the rods. The polarization
free energy of the assembly in a transverse field becomes lower than in a parallel field if the extent of the assembly (as
measured, for example, by the diameter of a cylindrical assembly) is larger than the length of the individual rods. We suggest
that this model may provide a reasonable explanation for the occurrence of “anomalous” birefringence in systems of interacting
charged rodlike particles. 相似文献
115.
Robinson T Valluri P Manning HB Owen DM Munro I Talbot CB Dunsby C Eccleston JF Baldwin GS Neil MA de Mello AJ French PM 《Optics letters》2008,33(16):1887-1889
Fluorescence lifetime imaging (FLIM) is used to quantitatively map the concentration of a small molecule in three dimensions in a microfluidic mixing device. The resulting experimental data are compared with computational fluid-dynamics (CFD) simulations. A line-scanning semiconfocal FLIM microscope allows the full mixing profile to be imaged in a single scan with submicrometer resolution over an arbitrary channel length from the point of confluence. Following experimental and CFD optimization, mixing times down to 1.3+/-0.4 ms were achieved with the single-layer microfluidic device. 相似文献
116.
Abstract Treatment of readily available monomethyl maleic acid (1) with three equivalents of methyl magnesium iodide followed by an excess of 2-methyl-1-propenyl magnesium bromide and a catalytic amount of CuBr produces d?-pyrocin (3) in a high yield. 相似文献
117.
Stack DW Peter N Manning RE Fristrup KM 《The Journal of the Acoustical Society of America》2011,129(3):1375-1380
Noise impacts resources and visitor experience in many protected natural areas, and visitors can be the dominant source of noise. This experimental study tested the efficacy and acceptability of signs asking visitors to be quiet at Muir Woods National Monument, California. Signs declaring a "quiet zone" (at the park's Cathedral Grove) or a "quiet day" (throughout the park) were posted on a randomized schedule that included control days (no signs). Visitor surveys were conducted to measure the cognitive and behavioral responses of visitors to the signs and test the acceptability of these management practices to visitors. Visitors were highly supportive of these management practices and reported that they consciously limited the amount of noise they produced. Sound level measurements showed substantial decreases on days when signs were posted. 相似文献
118.
R. J. Manning und M. Nierenstein 《Fresenius' Journal of Analytical Chemistry》1914,53(8):521-522
Ohne Zusammenfassung 相似文献
119.
Francis A. Appoh Stephanie S. Barnes Marcy J. Manning Courtney S. Turner Christopher M. Vogels Stephen A. Westcott Andreas Decken 《Journal of heterocyclic chemistry》2008,45(5):1415-1418
Condensation of aminoalcohols with 2‐HC(O)C6H4B(OH)2 afforded the macrocyclic compounds 1–7 with an OBOBO structural unit. Crystals of 1 were triclinic, space group P‐1, a = 9.9818(12) Å, b = 12.8302(15) Å, c = 13.1663(15) Å, α = 105.503(2)°, β = 94.860(2)°, γ = 92.585(2)°, Z = 2. 相似文献
120.