1,654 research outputs found
Study, fabrication and testing of a foil-bearing rotor support system
High speed foil bearing rotor support syste
Poplar tree buffer strips grown in riparian corridors for non-point source pollution control and biomass production
Throughout the Cornbelt eco-region, nitratenitrogen (NO3-N) is the most frequent pollutant exceeding the U.S. Environmental Protection Agency\u27s maximum contaminant limits for municipal drinking water supplies. Agricultural fertilizers that leach or run off from row-cropped fields are the principal source of NO3-N. This potential contamination poses a health concern that is attracting increasing attention among the urban and rural populace alike
Local states of free bose fields
These notes contain an extended version of lectures given at the ``Summer
School on Large Coulomb Systems'' in Nordfjordeid, Norway, in august 2003. They
furnish a short introduction to the theory of quantum harmonic systems, or free
bose fields. The main issue addressed is the one of local states. I will adopt
the definition of Knight of ``strictly local excitation of the vacuum'' and
will then state and prove a generalization of Knight's Theorem which asserts
that finite particle states cannot be perfectly localized. It will furthermore
be explained how Knight's a priori counterintuitive result can be readily
understood if one remembers the analogy between finite and infinite dimensional
harmonic systems alluded to above. I will also discuss the link between the
above result and the so-called Newton-Wigner position operator thereby
illuminating, I believe, the difficulties associated with the latter. I will in
particular argue that those difficulties do not find their origin in special
relativity or in any form of causality violation, as is usually claimed
Mineralization and Uptake of Triazine Pesticide in Soil-Plant Systems
Deep-Rooted Trees Planted as a Buffer Zone Can Intercept Runoff and Eroded Sediments, Thus Reducing Non-Point-Source Pollution Due to Agricultural Chemicals. in This Study, Populus Sp. Were Grown in Bioreactors with an Agricultural Soil (Silt-Loam) and in a Silica-Sand Media; Both Were Spiked with 14C Uniformly Ring-Labeled Atrazine. the Plants Took Up over 11% of the 14C Labeled Atrazine Applied to the Silt-Loam Soil and over 91% of that Applied to the Silica Sand Media, with the Majority of the 14C Accumulating as Nonphytotoxic Metabolites in the Leaves. Research Suggests that, in Addition to Nutrient Uptake, Poplar Tree Buffer Strips May Be Effective in Removing Atrazine from Agricultural Percolation and Runoff Water. © ASCE
A chiral bag model approach to delta electroproduction
Helicity amplitudes for the transition are calculated
using the cloudy bag model. A correction for center-of-mass motion is carried
out using a modified Peierls-Thouless projection method. This reduces the
magnitude of the transition amplitudes at small momentum transfer and enhances
them at modest momentum transfers. Our calculation shows that the pion cloud
contributes substantially to the transition helicity amplitudes, with the final
result giving reasonable agreement with the corresponding experimental values.Comment: 16 pages, 6 ps figures, revte
Eculizumab is a safe and effective treatment in pediatric patients with atypical hemolytic uremic syndrome
Atypical hemolytic uremic syndrome (aHUS) is caused by alternative complement pathway dysregulation, leading to systemic thrombotic microangiopathy (TMA) and severe end-organ damage. Based on 2 prospective studies in mostly adults and retrospective data in children, eculizumab, a terminal complement inhibitor, is approved for aHUS treatment. Here we prospectively evaluated efficacy and safety of weight-based dosing of eculizumab in eligible pediatric patients with aHUS in an open-label phase II study. The primary end point was complete TMA response by 26 weeks. Twenty-two patients (aged 5 months-17 years) were treated; 16 were newly diagnosed, 12 had no prior plasma exchange/infusion during current TMA symptomatology, 11 received baseline dialysis, and 2 had prior renal transplants. By week 26, 14 achieved a complete TMA response, 18 achieved hematologic normalization, and 16 had 25% or better improvement in serum creatinine. Plasma exchange/infusion was discontinued in all, and 9 of the 11 patients who required dialysis at baseline discontinued, whereas none initiated new dialysis. Eculizumab was well tolerated; no deaths or meningococcal infections occurred. Bone marrow failure, wrist fracture, and acute respiratory failure were reported as unrelated severe adverse events. Thus, our findings establish the efficacy and safety of eculizumab for pediatric patients with aHUS and are consistent with proposed immediate eculizumab initiation following diagnosis in children
Electromagnetic Form Factors of the Nucleon in an Improved Quark Model
Nucleon electromagnetic form factors are studied in the cloudy bag model
(CBM) with center-of-mass and recoil corrections. This is the first
presentation of a full set of nucleon form factors using the CBM. The center of
mass motion is eliminated via several different momentum projection techniques
and the results are compared. It is found that the shapes of these form factors
are significantly improved with respect to the experimental data if the Lorentz
contraction of the internal structure of the baryon is also appropriately taken
into account.Comment: revtex, 28 pages, 8 ps figs include
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