37 research outputs found

    Afshar's Experiment does not show a Violation of Complementarity

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    A recent experiment performed by S. Afshar [first reported by M. Chown, New Scientist {\bf 183}, 30 (2004)] is analyzed. It was claimed that this experiment could be interpreted as a demonstration of a violation of the principle of complementarity in quantum mechanics. Instead, it is shown here that it can be understood in terms of classical wave optics and the standard interpretation of quantum mechanics. Its performance is quantified and it is concluded that the experiment is suboptimal in the sense that it does not fully exhaust the limits imposed by quantum mechanics.Comment: 6 pages, 6 figure

    Sulfonated Styrene-(ethylene-co-butylene)-styrene/Montmorillonite Clay Nanocomposites: Synthesis, Morphology, and Properties

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    Sulfonated styrene-(ethylene-butylene)-styrene triblock copolymer (SSEBS) was synthesized by reaction of acetyl sulfate with SEBS. SSESB-clay nanocomposites were then prepared from hydrophilic Na-montmorillonite (MT) and organically (quaternary amine) modified hydrophobic nanoclay (OMT) at very low loading. SEBS did not show improvement in properties with MT-based nanocomposites. On sulfonation (3 and 6 weight%) of SEBS, hydrophilic MT clay-based nanocomposites exhibited better mechanical, dynamic mechanical, and thermal properties, and also controlled water–methanol mixture uptake and permeation and AC resistance. Microstructure determined by X-ray diffraction, atomic force microscopy, and transmission electron microscopy due to better dispersion of MT nanoclay particles and interaction of MT with SSEBS matrix was responsible for this effect. The resulting nanocomposites have potential as proton transfer membranes for Fuel Cell applications

    Benefit–risk of colchicine and spironolactone in acute myocardial infarction: a prespecified generalised pairwise comparisons analysis of the CLEAR trial

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    Background: Composite outcomes in cardiovascular trials often group events of unequal clinical importance, and conventional analyses may obscure treatment trade-offs. Generalised pairwise comparisons (GPC), expressed as a win ratio (WR), allow for hierarchical ranking of events and incorporation of recurrent outcomes, providing a potentially more intuitive assessment of benefit-risk. Methods: In a prespecified exploratory analysis of the 2×2 factorial, randomised CLEAR (Colchicine and Spironolactone in Patients with Myocardial Infarction) trial (7062 patients within 72 hours of acute myocardial infarction (MI) and percutaneous coronary intervention), we applied both time-to-first and recurrent-event GPC to reassess low-dose colchicine (0.5 mg daily) and spironolactone (25 mg daily) versus placebo. For the colchicine comparison, the hierarchical benefit-risk outcome included all-cause death, stroke, recurrent MI, unplanned ischaemia-driven revascularisation, serious infection or diarrhoea. For the spironolactone comparison, the outcome included all-cause death, stroke, MI, new or worsening heart failure, significant ventricular arrhythmia, hyperkalaemia or gynaecomastia/gynaecodynia. GPC results were compared with Cox, logistic and Andersen-Gill models. Results: For colchicine, the time-to-first event GPC showed a 12% lower proportional win rate compared with placebo (WR 0.88, 95% CI 0.79 to 0.98; win difference -2.10%, 95% CI -3.84 to -0.37), driven largely by excess diarrhoea. For spironolactone, patients experienced a 14% lower win rate (WR 0.86, 95% CI 0.75 to 0.99; win difference -1.46%, 95% CI -2.84% to -0.08%), largely attributable to gynaecomastia and hyperkalaemia. Conventional statistical approaches yielded concordant results. Across both interventions, higher-order efficacy outcomes (death, MI, stroke, heart failure) showed no benefit. Conclusions: In patients with post-MI, both low-dose colchicine and spironolactone demonstrated disadvantageous benefit-risk profiles, reinforcing that neither agent should be used routinely. This prespecified application of GPC provided results consistent with traditional methods but offered a clinically intuitive framework for interpreting composite outcomes

    Statistical strategies for avoiding false discoveries in metabolomics and related experiments

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    Charged-particle nuclear modification factors in PbPb and pPb collisions at √=sNN=5.02 TeV

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    The spectra of charged particles produced within the pseudorapidity window |η| < 1 at √ sNN = 5.02 TeV are measured using 404 µb −1 of PbPb and 27.4 pb−1 of pp data collected by the CMS detector at the LHC in 2015. The spectra are presented over the transverse momentum ranges spanning 0.5 < pT < 400 GeV in pp and 0.7 < pT < 400 GeV in PbPb collisions. The corresponding nuclear modification factor, RAA, is measured in bins of collision centrality. The RAA in the 5% most central collisions shows a maximal suppression by a factor of 7–8 in the pT region of 6–9 GeV. This dip is followed by an increase, which continues up to the highest pT measured, and approaches unity in the vicinity of pT = 200 GeV. The RAA is compared to theoretical predictions and earlier experimental results at lower collision energies. The newly measured pp spectrum is combined with the pPb spectrum previously published by the CMS collaboration to construct the pPb nuclear modification factor, RpA, up to 120 GeV. For pT > 20 GeV, RpA exhibits weak momentum dependence and shows a moderate enhancement above unity

    Professionals’ Practices and Views regarding Neonatal Postmortem: Can We Improve Consent Rates by Improving Training?

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    &lt;b&gt;&lt;i&gt;Background:&lt;/i&gt;&lt;/b&gt; In the UK, rates of neonatal postmortem (PM) are low. Consent for PM is required, and all parents should have the opportunity to discuss whether to have a post-mortem examination of their baby. &lt;b&gt;&lt;i&gt;Objectives:&lt;/i&gt;&lt;/b&gt; We aimed to explore neonatal healthcare professionals’ experiences, knowledge, and views regarding the consent process for post-mortem examination after neonatal death. &lt;b&gt;&lt;i&gt;Method:&lt;/i&gt;&lt;/b&gt; An online survey of neonatal healthcare providers in the UK was conducted. Responses from 103 healthcare professionals were analysed, 84 of whom were doctors. The response rate of the British Association of Perinatal Medicine (BAPM) members was 11.7%. &lt;b&gt;&lt;i&gt;Results:&lt;/i&gt;&lt;/b&gt; Perceived barriers to PM included cultural and religious practices of parents as well as a lack of rapport between parents and professionals. Of the respondents, 69.4% had observed a PM; these professionals had improved satisfaction with their training and confidence in counselling (&lt;i&gt;p&lt;/i&gt; &amp;#x3c; 0.001 and &lt;i&gt;p&lt;/i&gt; &amp;#x3c; 0.001) but not knowledge of the procedure (&lt;i&gt;p&lt;/i&gt; = 0.77). Healthcare professionals reported conservative estimates of the likelihood that a PM would identify significant information regarding the cause of death. &lt;b&gt;&lt;i&gt;Conclusions:&lt;/i&gt;&lt;/b&gt; Confidence of neonatal staff in counselling could be improved by observing a PM. Training for staff in developing a rapport with parents and addressing emotional distress may also overcome significant barriers to consent for PM.</jats:p
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