216 research outputs found
Multiple scattering and attenuation corrections in Deep Inelastic Neutron Scattering experiments
Multiple scattering and attenuation corrections in Deep Inelastic Neutron
Scattering experiments are analyzed. The theoretical basis is stated, and a
Monte Carlo procedure to perform the calculation is presented. The results are
compared with experimental data. The importance of the accuracy in the
description of the experimental parameters is tested, and the implications of
the present results on the data analysis procedures is examined.Comment: 19 pages, 8 figure
Formalism for obtaining nuclear momentum distributions by the Deep Inelastic Neutron Scattering technique
We present a new formalism to obtain momentum distributions in condensed
matter from Neutron Compton Profiles measured by the Deep Inelastic Neutron
Scattering technique. The formalism describes exactly the Neutron Compton
Profiles as an integral in the momentum variable . As a result we obtain a
Volterra equation of the first kind that relates the experimentally measured
magnitude with the momentum distributions of the nuclei in the sample. The
integration kernel is related with the incident neutron spectrum, the total
cross section of the filter analyzer and the detectors efficiency function. A
comparison of the present formalism with the customarily employed approximation
based on a convolution of the momentum distribution with a resolution function
is presented. We describe the inaccuracies that the use of this approximation
produces, and propose a new data treatment procedure based on the present
formalism.Comment: 11 pages, 8 figure
Analyses of microstructural variation in the human striatum using non-negative matrix factorization
The striatum is a major subcortical connection hub that has been heavily implicated in a wide array of motor and cognitive functions. Here, we developed a normative multimodal, data-driven microstructural parcellation of the striatum using non-negative matrix factorization (NMF) based on multiple magnetic resonance imaging-based metrics (mean diffusivity, fractional anisotropy, and the ratio between T1- and T2-weighted structural scans) from the Human Connectome Project Young Adult dataset (n = 329 unrelated participants, age range: 22–35, F/M: 185/144). We further explored the biological and functional relationships of this parcellation by relating our findings to motor and cognitive performance in tasks known to involve the striatum as well as demographics. We identified 5 spatially distinct striatal components for each hemisphere. We also show the gain in component stability when using multimodal versus unimodal metrics. Our findings suggest distinct microstructural patterns in the human striatum that are largely symmetric and that relate mostly to age and sex. Our work also highlights the putative functional relevance of these striatal components to different designations based on a Neurosynth meta-analysis
Conditional control of quantum beats in a cavity QED system
We probe a ground-state superposition that produces a quantum beat in the
intensity correlation of a two-mode cavity QED system. We mix drive with
scattered light from an atomic beam traversing the cavity, and effectively
measure the interference between the drive and the light from the atom. When a
photon escapes the cavity, and upon detection, it triggers our feedback which
modulates the drive at the same beat frequency but opposite phase for a given
time window. This results in a partial interruption of the beat oscillation in
the correlation function, that then returns to oscillate.Comment: 9 pages, 5 figures, XVII Reuni\'on Iberoamericana de \'Optica, X
Encuentro de \'Optica, L\'aseres y Aplicaciones (RIAO-OPTILAS-2010
Human placental Na+,K+-ATPase alpha subunit: cDNA cloning, tissue expression, DNA polymorphism, and chromosomal localization.
Moderators, Mediators, and Other Predictors of Risperidone Response in Children with Autistic Disorder and Irritability
Objective/Background:
The National Institute of Mental Health (NIMH) Research Units on Pediatric Psychopharmacology
(RUPP) Autism Network found an effect size of d = 1.2 in favor of risperidone on the main outcome measure
in an 8-week double-blind, placebo-controlled trial for irritabilityin autistic disorder. This paper explores
moderators and mediators of this effect.
Method:
Intention-to-treat (ITT) analyses were conducted with suspected moderators and mediators entered
into the regression equations. MacArthur Foundation Network subgroup guidelines were followed in the
evaluation of the results.
Results:
Only baseline severity moderated treatment response: Higher severity showed greater improvement
for risperidone but not for placebo. Weight gain mediated treatment response negatively: Those who gained
more weight improved less with risperidone and more with placebo. Compliance correlated with outcome for
risperidone but not placebo. Higher dose correlated with worse outcome for placebo, but not risperidone. Of
nonspecific predictors, parent education, family income, and low baseline prolactin positively predicted
outcome; anxiety, bipolar symptoms, oppositional-defiant symptoms, stereotypy, and hyperactivity
negatively predicted outcome. Risperidone moderated the effect of change in 5'-nucleotidase, a marker of
zinc status, for which decrease was associated with improvement only with risperidone, not with placebo.
Conclusion:
The benefit–risk ratio of risperidone is better with greater symptom severity. Risperidone can be
individually titrated to optimal dosage for excellent response in the majority of children. Weight gain is not
necessary for risperidone benefit and may even detract from it. Socioeconomic advantage, low prolactin, and
absence of co-morbid problems non-specifically predict better outcome. Mineral interactions with
risperidone deserve further study
Evaluation of pseudoephedrine pharmacy sales before and after mandatory recording requirements in Western Australia: a case study
Background: A community pharmacy real-time electronic recording program, ProjectSTOP, enables Australian community pharmacists to verify pseudoephedrine requests. In Western Australia the program was available for voluntary use from April 2007 and became mandatory November 2010. This case study explores the effectiveness of the program by reviewing the total requests for pseudoephedrine products, and the proportion of requests which were classified as ‘denied sales’ before and after mandatory implementation. Seasonal and annual trends in these measures are also evaluated. Methods: ProjectSTOP data recordings for Western Australia pharmacies between 1 December 2007 and 28 February 2014 were analysed. Data included a de-identified pharmacy number and date of each pseudoephedrine product request. The total number of requests and sale classification (allowed, denied, safety, or not recorded) were calculated for each month/pharmacy. The potential influence of mandatory reporting using ProjectSTOP was investigated using a Regression Discontinuity Design. Correlations between sales from the same pharmacy were taken into account by classifying the pharmacy number as a random effect. The main effects of year (continuous variable), and season (categorical variable) were also included in the model. Results: There was a small but steady decline in the total requests for pseudoephedrine per month per 100,000 population (per pharmacy) from the time of mandatory reporting. The number of denied sales showed a steady increase up until mandatory reporting, after which it showed a significant decline over time. Total sales were heavily influenced by season, as expected (highest in winter, least in summer). The seasonal pattern was less pronounced for denied sales, which were highest in winter and similar across other seasons. The pattern over time for safety sales was similar to that for denied sales, with a clear change occurring around the time of mandatory reporting. Conclusion: Results indicate a decrease in pseudoephedrine product requests in Western Australia community pharmacies. Findings suggest ProjectSTOP has been successful in addressing suspicious sales and potential diversion however ongoing data review is recommended
Oral vitamin K effectively treats international normalised ratio (INR) values in excess of 10. Results of a prospective cohort study
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