3,131 research outputs found
Isolated Photons in Deep Inelastic Scattering
Photon radiation at large transverse momenta at colliders is a detailed probe
of hard interaction dynamics. The isolated photon production cross section in
deep inelastic scattering was measured recently by the ZEUS experiment, and
found to be considerably larger than theoretical predictions obtained with
widely used event generators. To investigate this discrepancy, we perform a
dedicated parton-level calculation of this observable, including contributions
from fragmentation and large-angle radiation. Our results are in good agreement
with all aspects of the experimental measurement.Comment: 4 pages, 3 figure
The Contribution of Therapist Effects to Patient Dropout and Deterioration in the Psychological Therapies
BACKGROUND: In the psychological therapies, patient outcomes are not always positive. Some patients leave therapy prematurely (dropout), while others experience deterioration in their psychological well-being. METHODS: The sample for dropout comprised patients (n = 10 521) seen by 85 therapists, who attended at least the initial session of one-to-one therapy and completed a Clinical Outcomes in Routine Evaluation-Outcome Measure (CORE-OM) at pre-treatment. The subsample for patient deterioration comprised patients (n = 6405) seen by the same 85 therapists but who attended two or more sessions, completed therapy and returned a CORE-OM at pre-treatment and post-treatment. Multilevel modelling was used to estimate the extent of therapist effects for both outcomes after controlling for patient characteristics. RESULTS: Therapist effects accounted for 12.6% of dropout variance and 10.1% of deterioration variance. Dropout rates for therapists ranged from 1.2% to 73.2%, while rates of deterioration ranged from 0% to 15.4%. There was no significant correlation between therapist dropout rate and deterioration rate (Spearman's rho = 0.07, p = 0.52). CONCLUSIONS: The methods provide a reliable means for identifying therapists who return consistently poorer rates of patient dropout and deterioration compared with their peers. The variability between therapists and the identification of patient risk factors as significant predictors has implications for the delivery of safe psychological therapy services. Copyright © 2016 John Wiley & Sons, Ltd. KEY PRACTITIONER MESSAGE: Therapists play an important role in contributing to patient dropout and deterioration, irrespective of case mix. Therapist effects on patient dropout and deterioration appear to act independently. Being unemployed as a patient was the strongest predictor of both dropout and deterioration. Patient risk to self or others was also an important predictor
The Issues and Challenges of Assessing Media Literacy Education
In the media literacy literature, the challenges associated with assessment have, to a great extent, been ignored. The purpose of this mixed methods study was therefore to explore the views of media literacy scholars and professionals on assessment challenges through qualitative interviews (n = 10) with the intent of using this information to develop a quantitative survey to validate and extend the qualitative findings with a larger sample of media literacy professionals and scholars from around the world (n = 133). The findings offer an overview of the assessment challenges encountered by these participants
The Central Retail Food Market of Cleveland, Ohio
A study of the Central Retail Food Market in Cleveland, Ohio was made in 1947 at the request of Mayor Thomas A. Burke (Marketing and Facilities Research Branch 3 of the Production and Marketing Administration, U.S. Department of Agriculture) to determine the public need for a new market. In the previous year the city had voted favorably on a bond issue of $1,000,000 for the relocation and rebuilding of the market, provided it could be made self-supporting in a reasonable length of time. The Central Market building, built in 1857 and occupied until December 1949, when it was destroyed by fire....The final determination of whether or not a new public retail market should be built in downtown Cleveland to replace Central Market will have to be made by city officials (excerpt from survey summary).https://engagedscholarship.csuohio.edu/clevmembks/1023/thumbnail.jp
Exact results for `bouncing' Gaussian wave packets
We consider time-dependent Gaussian wave packet solutions of the Schrodinger
equation (with arbitrary initial central position, x_0, and momentum, p_0, for
an otherwise free-particle, but with an infinite wall at x=0, so-called
bouncing wave packets. We show how difference or mirror solutions of the form
psi(x,t)-psi(-x,t) can, in this case, be normalized exactly, allowing for the
evaluation of a number of time-dependent expectation values and other
quantities in closed form. For example, we calculate _t explicitly which
illustrates how the free-particle kinetic (and hence total) energy is affected
by the presence of the distant boundary. We also discuss the time dependence of
the expectation values of position, _t, and momentum, _t, and their
relation to the impulsive force during the `collision' with the wall. Finally,
the x_0,p_0 --> 0 limit is shown to reduce to a special case of a non-standard
free-particle Gaussian solution. The addition of this example to the literature
then expands on the relatively small number of Gaussian solutions to quantum
mechanical problems with familiar classical analogs (free particle, uniform
acceleration, harmonic oscillator, unstable oscillator, and uniform magnetic
field) available in closed form.Comment: 14 pages, 1 embedded .eps figur
The Stark effect in linear potentials
We examine the Stark effect (the second-order shift in the energy spectrum
due to an external constant force) for two 1-dimensional model quantum
mechanical systems described by linear potentials, the so-called quantum
bouncer (defined by V(z) = Fz for z>0 and V(z) infinite for z<0) and the
symmetric linear potential (given by V(z) = F|z|). We show how straightforward
use of the most obvious properties of the Airy function solutions and simple
Taylor expansions give closed form results for the Stark shifts in both
systems. These exact results are then compared to other approximation
techniques, such as perturbation theory and WKB methods. These expressions add
to the small number of closed-form descriptions available for the Stark effect
in model quantum mechanical systems.Comment: 15 pages. To appear in Eur. J. Phys. Needs Institute of Physics
(iopart) style file
The Central Retail Food Market of Cleveland, Ohio
A study of the Central Retail Food Market in Cleveland, Ohio was made in 1947 at the request of Mayor Thomas A. Burke (Marketing and Facilities Research Branch 3 of the Production and Marketing Administration, U.S. Department of Agriculture) to determine the public need for a new market. In the previous year the city had voted favorably on a bond issue of $1,000,000 for the relocation and rebuilding of the market, provided it could be made self-supporting in a reasonable length of time. The Central Market building, built in 1857 and occupied until December 1949, when it was destroyed by fire....The final determination of whether or not a new public retail market should be built in downtown Cleveland to replace Central Market will have to be made by city officials (excerpt from survey summary). Original publication date 1951.https://engagedscholarship.csuohio.edu/clevmembks/1023/thumbnail.jp
Acid-Labile Traceless Click Linker for Protein Transduction
Intracellular delivery of active proteins presents an interesting approach in research and therapy. We created a protein transduction shuttle based on a new traceless click linker that combines the advantages of click reactions with implementation of reversible pH-sensitive bonds. The azidomethyl-methylmaleic anhydride (AzMMMan) linker was found compatible with different click chemistries, demonstrated in bioreversible protein modification with dyes, polyethylene glycol, or a transduction carrier. Linkages were stable at physiological pH but reversible at the mild acidic pH of endosomes or lysosomes. We show that pH-reversible attachment of a defined endosome-destabilizing three-arm oligo(ethane amino)amide carrier generates an effective shuttle for protein delivery. The cargo protein nlsEGFP, when coupled via the traceless AzMMMan linker, experiences efficient cellular uptake and endosomal escape into the cytosol, followed by import into the nucleus. In contrast, irreversible linkage to the same shuttle hampers nuclear delivery of nlsEGFP which after uptake remains trapped in the cytosol. Successful intracellular delivery of bioactive Ăź-galactosidase as a model enzyme was also demonstrated using the pH-controlled shuttle system
Eikonal analysis of Coulomb distortion in quasi-elastic electron scattering
An eikonal expansion is used to provide systematic corrections to the eikonal
approximation through order , where is the wave number. Electron
wave functions are obtained for the Dirac equation with a Coulomb potential.
They are used to investigate distorted-wave matrix elements for quasi-elastic
electron scattering from a nucleus. A form of effective-momentum approximation
is obtained using trajectory-dependent eikonal phases and focusing factors.
Fixing the Coulomb distortion effects at the center of the nucleus, the
often-used ema approximation is recovered. Comparisons of these approximations
are made with full calculations using the electron eikonal wave functions. The
ema results are found to agree well with the full calculations.Comment: 12 pages, 6 Postscript figure
Analytic results for Gaussian wave packets in four model systems: II. Autocorrelation functions
The autocorrelation function, A(t), measures the overlap (in Hilbert space)
of a time-dependent quantum mechanical wave function, psi(x,t), with its
initial value, psi(x,0). It finds extensive use in the theoretical analysis and
experimental measurement of such phenomena as quantum wave packet revivals. We
evaluate explicit expressions for the autocorrelation function for
time-dependent Gaussian solutions of the Schrodinger equation corresponding to
the cases of a free particle, a particle undergoing uniform acceleration, a
particle in a harmonic oscillator potential, and a system corresponding to an
unstable equilibrium (the so-called `inverted' oscillator.) We emphasize the
importance of momentum-space methods where such calculations are often more
straightforwardly realized, as well as stressing their role in providing
complementary information to results obtained using position-space
wavefunctions.Comment: 18 pages, RevTeX, to appear in Found. Phys. Lett, Vol. 17, Dec. 200
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