12,829 research outputs found
Quantification of gliadin levels to the picogram level by flow cytometry
Celiac disease is a widely prevalent enteropathy caused by intolerance to gliadin, one of the gluten proteins. We developed two methods for the analysis of gliadin levels. Both methods use flow cytometry and rat antibodies against a 16-residue peptide of gliadin. The peptide is common to the alpha-, beta-, gamma-, and omega-gliadins
Conformal Anomalies and the Gravitational Effective Action: The Correlator for a Dirac Fermion
We compute in linearized gravity all the contributions to the gravitational
effective action due to a virtual Dirac fermion, related to the conformal
anomaly. This requires, in perturbation theory, the identification of the
gauge-gauge-graviton vertex off mass shell, involving the correlator of the
energy-momentum tensor and two vector currents (), which is responsible
for the generation of the gauge contributions to the conformal anomaly in
gravity. We also present the anomalous effective action in the inverse mass of
the fermion as in the Euler-Heisenberg case.Comment: 47 pages, 1 figure. Revised final version, contains 1 additional
section. Accepted for pubblication on Phys. Rev.
Searching for a continuum 4D field theory arising from a 5D non-abelian gauge theory
The anisotropic 5D SU(2) Yang-Mills model has been widely investigated on the
lattice during the last decade. In the case where all dimensions are large in
size, it was previously claimed that there is a new phase in the phase diagram,
called the Layer phase. In this phase, the gauge fields would be localized on
4D layers. Previous works claim that the phase transition to the Layer phase is
of second order, which would allow a continuum limit to be taken. We present
the extension of the previous work to large lattices, for which we found a
first order phase transition. This leaves the scenario that this 5D theory can
be dimensionally reduced to a continuum 4D field theory, doubtful.Comment: 6 pages, 2 figures - talk presented at the 31st International
Symposium on Lattice Field Theory - Lattice 2013, Mainz, German
Novel sulfur and selenium containing bis-α-amino acids from 4-hydroxyproline
The synthesis of new substituted prolines carrying at C-4 a second α-amino acid residue is reported. The amino acid, l-cysteine or l-selenocysteine, is linked to the proline ring through the sulfur or the selenium atom, respectively. The products were prepared with different stereochemistry at C-4, in few and clean high-yielding steps, with suitable protections for solid phase applications. The introduction of both sulfur and selenium atoms at C-4 of the proline ring seems to enhance significantly the cis geometry at the prolyl amide bond
Drinking wine at home: Hedonic analysis of sicilian wines using quantile regression
Abstract: In recent decades, the Sicilian wine industry has experienced a booming expansion because of the growing preferences of Italian consumers for Sicilian wines, especially in extra-regional markets. These consumers have been paying closer attention to Sicilian premium wines.
For this reason, the objective of this study is to inform professional investors and wine managers about the consumer preferences with respect to the most important segment categories of domestically consumed Sicilian wines. Using the quantile regression technique, we analyzed the
role of wine attributes and prices as an information tool in order to value for each wine segment the implicit price of the attributes affecting wine consumers\u2019 choices. The results indicate that Protected Designation of Origin (PDO) and Geographical Indication (PGI) certification is the main determinant in the wine price mechanisms and certified wines achieve premium prices that are progressively higher as the price level of the wine increases. Furthermore the effect of the brand on price formation seems to have a significant impact for low-end wines, whereas it has no specific impact on the price mechanism for high-end wines.
Keywords: Consumer Scan Dataset, Geographic Origin, Hedonic Price, Robust Regression, Wine Consumptio
Paper Session III-B - The Columbus Attached Laboratory
As an integral part of the manned core of the Space Station Freedom, the European Columbus Attached Laboratory is one of the three Laboratory Modules to provide an environment and facility for laboratory work, mcluding operational support to the crew.
Following the Preparatory Phase and major interfaces agreement reached between NASA and the International Partners, the Columbus Attached Laboratory has reached a level of definition which will allow proceeding with the full development phase.
This paper describes the main architectural and technical features of the current Columbus Attached Laboratory, as they have been derived from external and internal system requirements, in order to achieve overall performance capability and compatibility with the Space Station Freedom. Relevant aspects and design solutions are presented in the field of required resources, Payload and Crew accommodation.
The interoperability domain which regulates Columbus Attached Laboratory on-orbit life in its integrated role within the Space Station Freedom is also addressed in some of its main features. Concluding remarks cover the major steps of the design, development and qualification plan
Emission Line Properties of Seyfert Galaxies in the 12 Micron Sample
We present spectroscopy of emission lines for 81 Seyfert 1 and 104 Seyfert 2
galaxies in the IRAS 12m galaxy sample. We analyzed the emission-line
luminosity functions, reddening, and other gas diagnostics. The narrow-line
regions (NLR) of Sy1 and 2 galaxies do not significantly differ from each other
in most of these diagnostics. Combining the H/H ratio with a new
reddening indicator-the [SII]6720/[OII]3727 ratio, we find the average
for Sy1s and for Sy2s. The NLR of Sy1
galaxies has only marginally higher ionization than the Sy2s. Our sample
includes 22 Sy1.9s and 1.8s. In their narrow lines, these low-luminosity
Seyferts are more similar to the Sy2s than the Sy1s. We construct a BPT
diagram, and include the Sy1.8s and 1.9s. They overlap the region occupied by
the Sy2s. The C IV equivalent width correlates more strongly with [O
III]/H than with UV luminosity. The Sy1 and Sy2 luminosity functions of
[OII]3727 and [OIII]5007 are indistinguishable. Unlike the LF's of Seyfert
galaxies measured by SDSS, ours are nearly flat at low L. The larger number of
faint Sloan "AGN" is attributable to their inclusion of weakly emitting LINERs
and H II+AGN "composite" nuclei, which do not meet our classification criteria
for Seyferts. An Appendix investigates which emission line luminosities provide
the most reliable measures of the total non-stellar luminosity. The hard X-ray
or near-ultraviolet continuum luminosity can be crudely predicted from either
the [O III]5007 luminosity, or the combination of [O III]+H, or [N
II]+H lines, with a scatter of times for the Sy1s and
times for the Sy2s. The latter two hybrid (NLR+BLR) indicators have
the advantage of predicting the same HX luminosity independent of Seyfert type.Comment: 70 pages, including 15 Figures and 10 Tables. Accepted for
publication in The Astrophysical Journa
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