195 research outputs found
A cyclic-olefin-copolymer microfluidic immobilized-enzyme reactor for rapid digestion of proteins from dried blood spots
Magnetic interaction induced by the anomaly in kaon-photoproductions
We study the role of magnetic interaction in the photoproduction of the kaon
and hyperon. We find that the inclusion of a higher order diagram induced by
the Wess-Zumio-Witten term has a significant contribution to the magnetic
amplitude, which is compatible to the observed photon asymmetry in the forward
angle region. This enables us to use the K^* coupling constants which have been
determined in a microscopic way rather than the phenomenological ones which
differ largely from the microscopic ones.Comment: 8 pages, 3 figure
Forward-angle K+ Lambda photoproduction in a Regge-plus-resonance approach
We present an effective-Lagrangian description for forward-angle K+ Lambda
photoproduction from the proton, valid for photon lab energies from threshold
up to 16 GeV. The high-energy part of the amplitude is modeled in terms of
t-channel Regge-trajectory exchange. The sensitivity of the calculated
observables to the Regge-trajectory phase is investigated in detail. The model
is extended towards the resonance region by adding a number of s-channel
resonances to the t-channel background. The proposed hybrid
``Regge-plus-resonance'' (RPR) approach allows one to exploit the
p(gamma,K+)Lambda data in their entirety, resulting in stronger constraints on
both the background and resonance couplings. The high-energy data can be used
to fix the background contributions, leaving the resonance couplings as the
sole free parameters in the resonance region. We compare various
implementations of the RPR model, and explore to what extent the description of
the data can be improved by introducing the ``new'' resonances D13(1900) and
P11(1900). Despite its limited number of free parameters, the proposed RPR
approach provides an efficient description of the p(gamma,K+)Lambda dynamics in
and beyond the resonance region.Comment: 31 pages, 9 figures, accepted for publication in PRC. Section IIIB
modified to include the most recent data; discussion of results and
conclusions changed accordingl
Regge-plus-resonance treatment of the p(gamma,K^+)Sigma^0 and p(gamma,K^0)Sigma^+ reactions at forward kaon angles
An effective-Lagrangian framework for K Sigma photoproduction from the proton
is presented. The proposed model is applicable at forward kaon angles and
photon lab energies from threshold up to 16 GeV. The high-energy part of the
p(gamma,K^+)Sigma^0 and p(gamma,K^0)Sigma^+ amplitudes is expressed in terms of
Regge-trajectory exchange in the t channel. By supplementing this Regge
background with a number of s-channel resonances, the model is extended towards
the resonance region. The resulting ``Regge-plus-resonance'' (RPR) approach has
the advantage that the background contributions involve only a few parameters,
which can be largely constrained by the high-energy data. This work compares
various implementations of the RPR model, and explores which resonance
contributions are required to fit the data presently at hand. It is
demonstrated that, through the inclusion of one K and two K* trajectories, the
RPR framework provides an efficient and unified description of the K^+ Sigma^0
and K^0 Sigma^+ photoproduction channels over an extensive energy range.Comment: 33 pages, 15 figures; added discussion on new double-polarization
data (Cx and Cz) in Section I
Solvent-mediated extraction of fatty acids in bilayer oil paint models: a comparative analysis of solvent application methods
Electric and magnetic form factors of strange baryons
Predictions for the electromagnetic form factors of the Lambda$, Sigma and Xi
hyperons are presented. The numerical calculations are performed within the
framework of the fully relativistic constituent-quark model developed by the
Bonn group. The computed magnetic moments compare favorably with the
experimentally known values. Most magnetic form factors G_M(Q^2) can be
parametrized in terms of a dipole with cutoff masses ranging from 0.79 to 1.14
GeV.Comment: 15 pages, 8 figures, 3 tables, submitted to Eur. Phys. J.
Comparison of methods to estimate the affected body surface area and the dosage of topical treatments in psoriasis and atopic dermatitis : the advantage of a picture‐based tool
Background: The accurate determination of the dosage of topical treatments is important given its repercussions on patient adherence and therapeutic efficacy. Up till now, the fingertip unit calculated by the rule of hands is considered the gold standard, although its use is associated with several drawbacks.
Objective: To compare different methods to estimate the affected body surface area (BSA) and dosage of topical treatments in atopic dermatitis and psoriasis and investigate its reliability, user-friendliness and timing.
Methods: In this study, we compared the reliability of three different methods: (i) the fingertip unit calculated by the 1% hand rule; (ii) a picture-based tool [termed Cutaneous Inflammatory Disease Extent Score (CIDES)]; and (iii) a digital drawing tool. Eleven observers scored 40 patients with psoriasis and eczema to assess the inter-rater and intrarater reliability. Timing was automatically recorded, and user-friendliness was investigated by a questionnaire.
Results: An excellent intraclass correlation (ICC) was found for both inter-rater agreement and intrarater agreement for the picture-based tool (ICC = 0.92 and ICC = 0.96, respectively). The ICCs for drawing the area of involvement on a silhouette were 0.89 and 0.93, respectively. Finally, the rule of hands was associated with an increased inter-rater variability although an excellent intrarater agreement was found (ICC = 0.79 and 0.95, respectively). Automated calculation of the amount of topical treatment improved reliability, and CIDES was associated with the least variation. CIDES was considered the preferred method by all observers and was fast to perform (median: 30 s).
Conclusion: A picture-based method offered the most advantages (in terms of reliability, speed and user-friendliness) to estimate the affected BSA and calculate the dosage of topical treatments
Exclusive electroproduction of K+ Lambda and K+ Sigma^0 final states at Q^2 = 0.030-0.055 (GeV/c)^2
Cross section measurements of the exclusive p(e,e'K+)Lambda,Sigma^0
electroproduction reactions have been performed at the Mainz Microtron MAMI in
the A1 spectrometer facility using for the first time the Kaos spectrometer for
kaon detection. These processes were studied in a kinematical region not
covered by any previous experiment. The nucleon was probed in its third
resonance region with virtual photons of low four-momenta, Q^2= 0.030-0.055
(GeV/c)^2. The MAMI data indicate a smooth transition in Q^2 from
photoproduction to electroproduction cross sections. Comparison with
predictions of effective Lagrangian models based on the isobar approach reveal
that strong longitudinal couplings of the virtual photon to the N* resonances
can be excluded from these models.Comment: 16 pages, 7 figure
Dielectric barrier discharges used for the conversion of greenhouse gases: modeling the plasma chemistry by fluid simulations
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