3,384 research outputs found
Positive pion absorption on 3He using modern trinucleon wave functions
We study pion absorption on 3He employing trinucleon wave functions
calculated from modern realistic NN interactions (Paris, CD Bonn). Even though
the use of the new wave functions leads to a significant improvement over older
calculations with regard to both cross section and polarization data, there are
hints that polarization data with quasifree kinematics cannot be described by
just two-nucleon absorption mechanisms.Comment: 14 pages, 6 figure
Direct infusion mass spectrometry metabolomics dataset: a benchmark for data processing and quality control
Direct-infusion mass spectrometry (DIMS) metabolomics is an important approach for characterising molecular responses of organisms to disease, drugs and the environment. Increasingly large-scale metabolomics studies are being conducted, necessitating improvements in both bioanalytical and computational workflows to maintain data quality. This dataset represents a systematic evaluation of the reproducibility of a multi-batch DIMS metabolomics study of cardiac tissue extracts. It comprises of twenty biological samples (cow vs. sheep) that were analysed repeatedly, in 8 batches across 7 days, together with a concurrent set of quality control (QC) samples. Data are presented from each step of the workflow and are available in MetaboLights. The strength of the dataset is that intra- and inter-batch variation can be corrected using QC spectra and the quality of this correction assessed independently using the repeatedly-measured biological samples. Originally designed to test the efficacy of a batch-correction algorithm, it will enable others to evaluate novel data processing algorithms. Furthermore, this dataset serves as a benchmark for DIMS metabolomics, derived using best-practice workflows and rigorous quality assessment
Can copper-coated surfaces prevent healthcare-associated infections?
Despite dramatic decreases in the incidence of healthcareassociated
infections (HAIs) in recent years, a large prevalence
study of US acute-care hospitals estimated that ~722,000 HAIs
occurred in 2011, resulting in ~75,000 deaths.1 Several
decades ago, Weinstein2 theorized that pathogens causing HAIs
in the intensive care unit (ICU) had several sources: the patients’
endogenous flora (40%–60%), cross-infection via the hands of
healthcare personnel (HCP; 20%–40%), antibiotic-driven
changes in flora (20%–25%), and other causes (including
contamination of the environment; 20%).2 More recently,
accumulating scientific evidence has indicated that contamination
of environmental surfaces in hospital rooms plays an
important role in the transmission of several key healthcareassociated
pathogens, including methicillin-resistant Staphylococcus
aureus (MRSA), vancomycin-resistant Enterococcus spp
(VRE), Clostridium difficile, Acinetobacter spp, and noroviru
Ariel - Volume 4 Number 6
Editors
David A. Jacoby
Eugenia Miller
Tom Williams
Associate Editors
Paul Bialas
Terry Burt
Michael Leo
Gail Tenikat
Editor Emeritus and Business Manager
Richard J. Bonnano
Movie Editor
Robert Breckenridge
Staff
Richard Blutstein
Mary F. Buechler
J.D. Kanofsky
Rocket Weber
David Maye
Correlation of tissue-typing tests in baboon renal allotransplants
Click on the link to view
Quasifree photoabsorption on neutron-proton pairs in 3He
Three-body photodisintegration of 3He is calculated in the photon energy
range 200 - 400 MeV assuming quasifree absorption on np pairs both in initial
quasideuteron and singlet configurations. The model includes the normal
nucleonic current, explicit meson exchange currents and the Delta(1232)-isobar
excitation. The total cross section is increased by a factor of about 1.5
compared with free deuteron photodisintegration. Well below and above the Delta
region also some spin observables differ significantly from the ones of free
deuteron disintegration due to the more compressed wave function of the
correlated np pairs in 3He compared to the deuteron. The initial singlet state
causes a significant change in the analyzing power Ay. These differences could
presumably be seen at the conjugate angles where two-body effects are maximized
and where photoreactions could complement similar pion absorption experiments.
Figures by fax or post from [email protected]: 23 pages, report MKPH-T-94-10/HU-TFT-94-1
The geographic scaling of biotic interactions
A central tenet of ecology and biogeography is that the broad outlines of species ranges are determined by climate, whereas the effects of biotic interactions are manifested at local scales. While the first proposition is supported by ample evidence, the second is still a matter of controversy. To address this question, we develop a mathematical model that predicts the spatial overlap, i.e. co-occurrence, between pairs of species subject to all possible types of interactions. We then identify the scale of resolution in which predicted range overlaps are lost. We found that co-occurrence arising from positive interactions, such as mutualism (+/+) and commensalism (+/0), are manifested across scales. Negative interactions, such as competition (-/-) and amensalism (-/0), generate checkerboard patterns of co-occurrence that are discernible at finer resolutions but that are lost and increasing scales of resolution. Scale dependence in consumer-resource interactions (+/-) depends on the strength of positive dependencies between species. If the net positive effect is greater than the net negative effect, then interactions scale up similarly to positive interactions. Our results challenge the widely held view that climate alone is sufficient to characterize species distributions at broad scales, but also demonstrate that the spatial signature of competition is unlikely to be discernible beyond local and regional scales. © 2013 The Authors.Peer Reviewe
The detection of Gravitational Waves
This chapter is concerned with the question: how do gravitational waves (GWs)
interact with their detectors? It is intended to be a theory review of the
fundamental concepts involved in interferometric and acoustic (Weber bar) GW
antennas. In particular, the type of signal the GW deposits in the detector in
each case will be assessed, as well as its intensity and deconvolution. Brief
reference will also be made to detector sensitivity characterisation, including
very summary data on current state of the art GW detectors.Comment: 33 pages, 12 figures, LaTeX2e, Springer style files --included. For
Proceedings of the ERE-2001 Conference (Madrid, September 2001
Using Molecular Conformers in COSMO-RS to Predict Drug Solubility in Mixed Solvents
This work explores the impact of solute conformers on the conductor-like screening model for real solvents (COSMO-RS) solubility predictions of vanillin and ethyl vanillin in water, short alcohols, and their mixed solvents. Two major conformers of these solutes and changes with solvent polarity were experimentally established by Raman spectroscopy and further confirmed by density functional theory calculations. The COSMO-RS predictions using the individual conformers show a poor description of the solubilities. Estimation with the COSMO-RS default conformer distribution gave better predictions and an intermediate behavior between the predictions obtained using each individual conformer. To further improve the description of the solubilities, the weight of each conformer was fitted to the experimental solid-liquid equilibrium data of the solute in a pure solvent at different temperatures. Better solubility predictions in ternary systems describing solubility maxima were found, suggesting a semipredictive approach to COSMO-RS. This method can predict the liquid-liquid oiling-out effect in the studied binary and ternary systems.This work was developed within the scope of the project
CICECO-Aveiro Institute of Materials, UIDB/50011/2020, UIDP/50011/2020, and LA/P/0006/2020, and CIMOMountain
Research Center, UIDB/00690/2020 and LA/P/0007/2020, financed by national funds through the Portuguese
Foundation for Science and Technology/MCTES. G.T. thanks
FCT for his Ph.D. grant (UI/BD/151114/2021). I.W.C. thanks FCT for her Ph.D. grant (2022.12407.BD).info:eu-repo/semantics/publishedVersio
- …