10 research outputs found

    Quantum mechanics of Van der Waals complexes: rare gas-hydrocarbon systems

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    The coupled channel approach has been used to study the Van der Waals complexes Ar-C(_2)H(_2), Ar-CH(_4) and Ar-C(_2)H(_4). The Ar-C(_2)H(_2) study employs a pairwise additive, atom-atom potential energy surface first without, and then with, angular anisotropy in some of the carbon atom parameters. The complex is found to be a nearly free internal rotor and the correlation between the complex and the acetylene monomer energy levels is clear. The Ar-CH(_4) study uses two potentials. The first includes the isotropic V(_o) dependence and the first angularly anisotropic V(_3) term. This is then modified to give a second potential which includes a V(_4) term as well. The role of these anisotropic terms in splitting the triply degenerate bending states of the complex, when the methane monomer is in the ground vibrational state, is discussed. The energy level pattern is found to be best described in terms of a hindered rotor model. For Ar-C(_2)H(_4) a pairwise additive, atom-atom potential including angular anisotropy in the carbon atom parameters is again used. The ethylene monomer in the complex is nearly free to rotate about the C-C axis but steric considerations make end-over-end rotation restricted. A method has been implemented to extract wavefunctions from coupled channel calculations. The utility of this technique has been illustrated by providing insights into the Ar-HF, He-CO(_2) and Ar-C(_2)H(_4) systems via calculated spectra and direct visualisation of the wavefunctions

    Mid-Infrared Spectroscopy of Two Lensed Star-forming Galaxies

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    We present low-resolution, rest-frame ~ 5 - 12 micron Spitzer/IRS spectra of two lensed z ~ 2 UV-bright star-forming galaxies, SDSS J120602.09+514229.5 and SDSS J090122.37+181432.3. Using the magnification boost from lensing, we are able to study the physical properties of these objects in greater detail than is possible for unlensed systems. In both targets, we detect strong PAH emission at 6.2, 7.7, and 11.3 microns, indicating the presence of vigorous star formation. For J1206, we find a steeply rising continuum and significant [S IV] emission, suggesting that a moderately hard radiation field is powering continuum emission from small dust grains. The strength of the [S IV] emission also implies a sub-solar metallicity of ~ 0.5 Z_{Sun}, confirming published rest-frame optical measurements. In J0901, the PAH lines have large rest-frame equivalent widths (> 1 micron) and the continuum rises slowly with wavelength, suggesting that any AGN contribution to L_{IR} is insignificant, in contrast to the implications of optical emission-line diagnostics. Using [O III] line flux as a proxy for AGN strength, we estimate that the AGN in J0901 provides only a small fraction of its mid-infrared continuum flux. By combining the detection of [Ar II] with an upper limit on [Ar III] emission, we infer a metallicity of > 1.3 Z_{Sun}. This work highlights the importance of combining rest-frame optical and mid-IR spectroscopy in order to understand the detailed properties of star-forming galaxies at high redshift.Comment: 20 pages, 3 figures, 2 tables. ApJ accepte

    Data from a pre-publication independent replication initiative examining ten moral judgement effects

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    We present the data from a crowdsourced project seeking to replicate findings in independent laboratories before (rather than after) they are published. In this Pre-Publication Independent Replication (PPIR) initiative, 25 research groups attempted to replicate 10 moral judgment effects from a single laboratory's research pipeline of unpublished findings. The 10 effects were investigated using online/lab surveys containing psychological manipulations (vignettes) followed by questionnaires. Results revealed a mix of reliable, unreliable, and culturally moderated findings. Unlike any previous replication project, this dataset includes the data from not only the replications but also from the original studies, creating a unique corpus that researchers can use to better understand reproducibility and irreproducibility in science

    Early and empirical high-dose cryoprecipitate for hemorrhage after traumatic injury: The CRYOSTAT-2 randomized clinical trial

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    Critical bleeding is associated with a high mortality rate in patients with trauma. Hemorrhage is exacerbated by a complex derangement of coagulation, including an acute fibrinogen deficiency. Management is fibrinogen replacement with cryoprecipitate transfusions or fibrinogen concentrate, usually administered relatively late during hemorrhage. To assess whether survival could be improved by administering an early and empirical high dose of cryoprecipitate to all patients with trauma and bleeding that required activation of a major hemorrhage protocol. CRYOSTAT-2 was an interventional, randomized, open-label, parallel-group controlled, international, multicenter study. Patients were enrolled at 26 UK and US major trauma centers from August 2017 to November 2021. Eligible patients were injured adults requiring activation of the hospital's major hemorrhage protocol with evidence of active hemorrhage, systolic blood pressure less than 90 mm Hg at any time, and receiving at least 1 U of a blood component transfusion. Patients were randomly assigned (in a 1:1 ratio) to receive standard care, which was the local major hemorrhage protocol (reviewed for guideline adherence), or cryoprecipitate, in which 3 pools of cryoprecipitate (6-g fibrinogen equivalent) were to be administered in addition to standard care within 90 minutes of randomization and 3 hours of injury. The primary outcome was all-cause mortality at 28 days in the intention-to-treat population. Among 1604 eligible patients, 799 were randomized to the cryoprecipitate group and 805 to the standard care group. Missing primary outcome data occurred in 73 patients (principally due to withdrawal of consent) and 1531 (95%) were included in the primary analysis population. The median (IQR) age of participants was 39 (26-55) years, 1251 (79%) were men, median (IQR) Injury Severity Score was 29 (18-43), 36% had penetrating injury, and 33% had systolic blood pressure less than 90 mm Hg at hospital arrival. All-cause 28-day mortality in the intention-to-treat population was 26.1% in the standard care group vs 25.3% in the cryoprecipitate group (odds ratio, 0.96 [95% CI, 0.75-1.23]; P = .74). There was no difference in safety outcomes or incidence of thrombotic events in the standard care vs cryoprecipitate group (12.9% vs 12.7%). Among patients with trauma and bleeding who required activation of a major hemorrhage protocol, the addition of early and empirical high-dose cryoprecipitate to standard care did not improve all cause 28-day mortality. ClinicalTrials.gov Identifier: NCT04704869; ISRCTN Identifier: ISRCTN14998314

    Data from a pre-publication independent replication initiative examining ten moral judgement effects

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    We present the data from a crowdsourced project seeking to replicate findings in independent laboratories before (rather than after) they are published. In this Pre-Publication Independent Replication (PPIR) initiative, 25 research groups attempted to replicate 10 moral judgment effects from a single laboratory's research pipeline of unpublished findings. The 10 effects were investigated using online/lab surveys containing psychological manipulations (vignettes) followed by questionnaires. Results revealed a mix of reliable, unreliable, and culturally moderated findings. Unlike any previous replication project, this dataset includes the data from not only the replications but also from the original studies, creating a unique corpus that researchers can use to better understand reproducibility and irreproducibility in science.Link_to_subscribed_fulltex

    What's in a Name? Would a Rose by Any Other Name Really Smell as Sweet?

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    Adaptation of the Wound Healing Questionnaire universal-reporter outcome measure for use in global surgery trials (TALON-1 study): mixed-methods study and Rasch analysis

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    BackgroundThe Bluebelle Wound Healing Questionnaire (WHQ) is a universal-reporter outcome measure developed in the UK for remote detection of surgical-site infection after abdominal surgery. This study aimed to explore cross-cultural equivalence, acceptability, and content validity of the WHQ for use across low- and middle-income countries, and to make recommendations for its adaptation.MethodsThis was a mixed-methods study within a trial (SWAT) embedded in an international randomized trial, conducted according to best practice guidelines, and co-produced with community and patient partners (TALON-1). Structured interviews and focus groups were used to gather data regarding cross-cultural, cross-contextual equivalence of the individual items and scale, and conduct a translatability assessment. Translation was completed into five languages in accordance with Mapi recommendations. Next, data from a prospective cohort (SWAT) were interpreted using Rasch analysis to explore scaling and measurement properties of the WHQ. Finally, qualitative and quantitative data were triangulated using a modified, exploratory, instrumental design model.ResultsIn the qualitative phase, 10 structured interviews and six focus groups took place with a total of 47 investigators across six countries. Themes related to comprehension, response mapping, retrieval, and judgement were identified with rich cross-cultural insights. In the quantitative phase, an exploratory Rasch model was fitted to data from 537 patients (369 excluding extremes). Owing to the number of extreme (floor) values, the overall level of power was low. The single WHQ scale satisfied tests of unidimensionality, indicating validity of the ordinal total WHQ score. There was significant overall model misfit of five items (5, 9, 14, 15, 16) and local dependency in 11 item pairs. The person separation index was estimated as 0.48 suggesting weak discrimination between classes, whereas Cronbach's α was high at 0.86. Triangulation of qualitative data with the Rasch analysis supported recommendations for cross-cultural adaptation of the WHQ items 1 (redness), 3 (clear fluid), 7 (deep wound opening), 10 (pain), 11 (fever), 15 (antibiotics), 16 (debridement), 18 (drainage), and 19 (reoperation). Changes to three item response categories (1, not at all; 2, a little; 3, a lot) were adopted for symptom items 1 to 10, and two categories (0, no; 1, yes) for item 11 (fever).ConclusionThis study made recommendations for cross-cultural adaptation of the WHQ for use in global surgical research and practice, using co-produced mixed-methods data from three continents. Translations are now available for implementation into remote wound assessment pathways
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