829 research outputs found
The Riemann Surface of a Static Dispersion Model and Regge Trajectories
The S-matrix in the static limit of a dispersion relation is a matrix of a
finite order N of meromorphic functions of energy in the plane with
cuts . In the elastic case it reduces to N functions
connected by the crossing symmetry matrix A. The scattering of
a neutral pseodoscalar meson with an arbitrary angular momentum l at a source
with spin 1/2 is considered (N=2). The Regge trajectories of this model are
explicitly found.Comment: 5 pages, LaTe
Analytic Approach to Perturbative QCD
The two-loop invariant (running) coupling of QCD is written in terms of the
Lambert W function. The analyticity structure of the coupling in the complex
Q^2-plane is established. The corresponding analytic coupling is reconstructed
via a dispersion relation. We also consider some other approximations to the
QCD beta-function, when the corresponding couplings are solved in terms of the
Lambert function. The Landau gauge gluon propagator has been considered in the
renormalization group invariant analytic approach (IAA). It is shown that there
is a nonperturbative ambiguity in determination of the anomalous dimension
function of the gluon field. Several analytic solutions for the propagator at
the one-loop order are constructed. Properties of the obtained analytical
solutions are discussed.Comment: Latex-file, 19 pages, 2 tables, 51 references, to be published in
Int. J. Mod. Phys.
Dualities in all order finite N=1 gauge theories
We search for dual gauge theories of all-loop finite, N = 1 supersymmetric
gauge theories. It is shown how to find explicitly the dual gauge theories of
almost all chiral, N = 1, all-loop finite gauge theories, while several models
have been discussed in detail, including a realistic finite SU(5) unified
theory. Out of our search only one all-loop, N = 1 finite SO(10) theory
emerges, so far, as a candidate for exhibiting also S-duality.Comment: 54 pages, latex, 2 figure
On the infrared freezing of perturbative QCD in the Minkowskian region
The infrared freezing of observables is known to hold at fixed orders of
perturbative QCD if the Minkowskian quantities are defined through the analytic
continuation from the Euclidean region. In a recent paper [1] it is claimed
that infrared freezing can be proved also for Borel resummed all-orders
quantities in perturbative QCD. In the present paper we obtain the Minkowskian
quantities by the analytic continuation of the all-orders Euclidean amplitudes
expressed in terms of the inverse Mellin transform of the corresponding Borel
functions [2]. Our result shows that if the principle of analytic continuation
is preserved in Borel-type resummations, the Minkowskian quantities exhibit a
divergent increase in the infrared regime, which contradicts the claim made in
[1]. We discuss the arguments given in [1] and show that the special
redefinition of Borel summation at low energies adopted there does not
reproduce the lowest order result obtained by analytic continuation.Comment: 19 pages, 1 figur
Baryonic Regge trajectories with analyticity constraints
A model for baryonic Regge trajectories compatible with the threshold
behavior required by unitarity and asymptotic behavior in agreement with
analyticity constraints is given in explicit form. Widths and masses of the
baryonic resonances on the N and trajectories are reproduced. The
MacDowell symmetry is exploited and an application is given.Comment: 12 pages, 6 figure
Adverse drug reactions in hospitalized children in Germany are decreasing: results of a nine year cohort-based comparison
published_or_final_versio
Highly resolved intravital striped-illumination microscopy of germinal centers
Monitoring cellular communication by intravital deep-tissue multi-photon microscopy is the key for understanding the fate of immune cells within thick tissue samples and organs in health and disease. By controlling the scanning pattern in multi-photon microscopy and applying appropriate numerical algorithms, we developed a striped-illumination approach, which enabled us to achieve 3-fold better axial resolution and improved signal-to-noise ratio, i.e. contrast, in more than 100 µm tissue depth within highly scattering tissue of lymphoid organs as compared to standard multi-photon microscopy. The acquisition speed as well as photobleaching and photodamage effects were similar to standard photo-multiplier-based technique, whereas the imaging depth was slightly lower due to the use of field detectors. By using the striped-illumination approach, we are able to observe the dynamics of immune complex deposits on secondary follicular dendritic cells - on the level of a few protein molecules in germinal centers
A First Response: Educating Paramedics to Identify Signs of Human Trafficking
Introduction: Human trafficking (HT) affects approximately 21 million victims, representing a serious public health concern exacerbated by missed intervention opportunities. Targeted training has previously resulted in increased victim identification. While intervention with hospital staff increased HT awareness, less is known about prehospital personnel, specifically emergency medical services (EMS) personnel. This gap is problematic, as EMS personnel are uniquely positioned to conduct patient and environmental assessments that provide critical information for victim identification. This study evaluates a training module specifically designed for EMS professionals.
Methods: The online training module was developed in collaboration with Florida State University. Data were collected anonymously using voluntary pre- and post-tests. In total, 237 participants (majority American, n=224) completed at least 80% of the questions which asked about identification of HT indicators, previous training, frequency of suspected contact, and demographics. Data were analyzed using descriptive and bivariate statistics.
Results: Preliminary results suggest training effectively educates EMS personnel to recognize signs of HT. Paired-samples t-tests demonstrate increased suspicion for 26/27 indicators; the likelihood of suspecting HT before (m=107.23, SD=16.23) versus after training (m=118.61, SD=15.90) based on summed values of all indicators was statistically significant; t(208)=-9.129, p\u3c.001.
Conclusions: This research falls under the Grand Theme of ‘Building Viable, Healthy, and Safe Communities’ by describing efforts to raise the visibility of HT among paramedics. Training may provide knowledge and confidence to report HT to resources equipped to effectively intervene. Training EMS personnel in HT will help fight modern day slavery and create healthier and safer communitie
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