196 research outputs found
Black-body photon clustering by semi-classical means
If stimulated emission could be turned off then only uncorrelated photons
would be emitted from black bodies and the photon counting statistics would be
Poissonian. Through the process of stimulated emission, some fraction of the
photons emitted from a black body are correlated and thus emitted in clusters.
This photon clustering can be calculated by semi-classical means. The
corresponding results are in agreement with quantum theory.Comment: 10 pages, 2 figures, 1 table. Added proof that stimulated-emission
produced photon clustering at the source leads to the Hanbury Brown and Twiss
effect without invoking photon-photon interference. Fixed unit mistakes in
the left hand side of Eqs (4), (6), (7), and (9
Difficult intubation and extubation in adult anaesthesia.
To provide an update to French guidelines about "Difficult intubation and extubation in adult anaesthesia 2006".
A consensus committee of 13 experts was convened. A formal conflict-of-interest (COI) policy was developed at the onset of the process and enforced throughout. The entire guidelines process was conducted independent of any industry funding. The authors were advised to follow the principles of the Grading of Recommendations Assessment, Development and Evaluation (GRADE) system to guide assessment of quality of evidence. The potential drawbacks of making strong recommendations in the presence of low-quality evidence were emphasized. Few recommendations were ungraded.
The panel focused on 6 questions: 1) Why must oxygen desaturation be avoided during intubation and what preoxygenation and oxygenation techniques should be used to prevent it? 2) Should videolaryngoscopes be used instead of standard laryngoscopy with or without a long stylet to achieve a better success rate of intubation after the first attempt during anticipated difficult intubation off fiberoptic intubation? 3) Should TCI or target controlled inhalation anaesthesia (TCIA) be used instead of bolus sedation for airway control in the event of suspected or proven difficulty in a patient spontaneously breathing? 4) What mode of anaesthesia should be performed in patients with difficult intubation criteria and potentially difficult mask ventilation? 5) In surgical patients, what criteria predict difficulties encountered during postoperative tracheal extubation? 6) Should decision trees and algorithms be employed to direct decision-making for the management of difficult intubation, whether foreseen or not? (based on the information from the preceding five issues). Population, intervention, comparison, and outcomes (PICO) questions were reviewed and updated as needed, and evidence profiles were generated. The analysis of the literature and the recommendations were then conducted according to the GRADE <sup>®</sup> methodology.
The SFAR Guideline panel provided 13 statements on difficult intubation and extubation in adult anaesthesia. After two rounds of discussion and various amendments, a strong agreement was reached for 99% of recommendations. Of these recommendations, five have a high level of evidence (Grade 1±), 8 have a low level of evidence (Grade 2±). No recommendation was provided for one question.
Substantial agreement exists among experts regarding many strong recommendations for the best care of patients with difficult intubation and extubation in adult anaesthesia
Handling unfavourable polarization states in a polarization-based shearing speckle interferometer
Limits on the production of scalar leptoquarks from Z (0) decays at LEP
A search has been made for pairs and for single production of scalar leptoquarks of the first and second generations using a data sample of 392000 Z0 decays from the DELPHI detector at LEP 1. No signal was found and limits on the leptoquark mass, production cross section and branching ratio were set. A mass limit at 95% confidence level of 45.5 GeV/c2 was obtained for leptoquark pair production. The search for the production of a single leptoquark probed the mass region above this limit and its results exclude first and second generation leptoquarks D0 with masses below 65 GeV/c2 and 73 GeV/c2 respectively, at 95% confidence level, assuming that the D0lq Yukawa coupling alpha(lambda) is equal to the electromagnetic one. An upper limit is also given on the coupling alpha(lambda) as a function of the leptoquark mass m(D0)
Invariant mass dependence of particle correlations in hadronic final states from the decay of the Z
Samarium(II)-Mediated 4-exo-trig Cyclization. A Stereocontrolled Approach to the Core of Pestalotiopsin A
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