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We present the second dust continuum data release in the Census of High- and Medium-mass Protostars (CHaMP), expanding the methodology trialed in Pitts et al. to the entire CHaMP survey area (280 degrees < l < 300 degrees, - 4 degrees < b < + 2 degrees). This release includes maps of dust temperature (T-d), H-2 column density (NH2), gas-phase CO abundance, and temperature-density plots for every prestellar clump with Herschel coverage, showing no evidence of internal heating for most clumps in our sample. We show that CO abundance is a strong function of T-d and can be fit with a second-order polynomial in log-space, with a typical dispersion of a factor of 2-3. The CO abundance peaks at 20.0(-1.0)(+0.4) K with a value of 7.4(-0.3)(+0.2) x 10(-5) per H-2; the low T-d at which this maximal abundance occurs relative to laboratory results is likely due to interstellar UV bombardment in the largest survey fields. Finally, we show that, as predicted by theoretical literature and hinted at in previous studies of individual clouds, the conversion factor from integrated (CO)-C-12 line intensity ((ICO)-C-12) to NH2, the X-CO factor, varies as a broken power law in I-CO(12) with a transition zone between 70 and 90 K km s(-1). The X-CO function we propose has NH2 proportional to I-12CO(0.51) for I-12CO less than or similar to 70 K km s(-1) N-H2 proportional to I-12CO(2.3) for I-12CO greater than or similar to 90 K km s(-1) The high-I-12CO side should be generalizable with known adjustments for metallicity, but the influence of interstellar UV fields on the low-I-12CO side may be sample specific. We discuss how these results expand on previous works in the CHaMP series and help tie together observational, theoretical, and laboratory studies on CO over the past decade.
The effect of inhaled capsaicin, the irritant extract of pepper, on airway tone has been studied in humans. Inhaled capsaicin (2.4 X 10(-10) and 2.4 X 10(-9) mol) caused a dose-dependent fall in specific airways conductance (maximum fall 28 +/- 19 and 38 +/- 19%, respectively; means +/- SD, n = 17). This was maximal within 20 s of exposure and lasted for less than 60 s. There was no difference in the magnitude or duration of bronchoconstriction between normal, smoking, or asthmatic subjects. Capsaicin also caused coughing and retrosternal discomfort. On repeated exposure to capsaicin, there was no evidence for a reduced response (tachyphylaxis). Ipratropium bromide (0.25 mg by inhalation) significantly (P less than 0.05) reduced the bronchoconstriction (maximum falls 34 +/- 14 and 15 +/- 9% after saline and ipratropium bromide, respectively; means +/- SD n = 6), indicating that it was dependent on a cholinergic vagal reflex rather than on local release of substance P from nerves in the airway. Inhaled sodium cromoglycate (10 mg by nebulizer or 40 mg as a dry powder), however, had no significant effect on the bronchoconstrictor response. Capsaicin may be a useful tool for investigating nonmyelinated nerve reflexes in human airways.
An analytical model that describes a thin-walled I-section column under pure compression based on variational principles is presented. The Rayleigh–Ritz method is combined with continuous displacement functions to formulate the total potential energy that is minimized. A system of differential and integral equilibrium equations is formulated for the structural component for which numerical continuation reveals progressive cellular buckling (or snaking) arising from the nonlinear interaction between the weakly stable overall mode and the strongly stable local buckling mode. The resulting behaviour is highly unstable and is postulated to be highly sensitive to initial geometric imperfections.
To answer the question whether intracoronary thrombolysis in patients with acute myocardial infarction is beneficial, a randomised trial was started in June 1981 at the Thoraxcenter: so far, 167 patients admitted less than 4 h after onset of symptoms have been enrolled. This interim report describes the effects of reperfusion versus conventional treatment on early and late mortality as well as on global and regional left ventricular function assessed from contrast angiography 2 weeks after the acute phase. In the conventionally treated group (N = 82), 8 patients died in hospital and 7 after discharge {median follow-up 13 months). In the group assigned to thrombolysis (N = 85), 6 patients died in hospital and 4 after discharge. In contrast to this nonsignificant difference in mortality, the haemodynamic data showed a preservation of global left ventricular function after thrombolysis, even when the results were presented on an 'intention to treat' basis. The left ventricular ejection fraction was 56 ± 10% (mean ± SD) in the thrombolysis group versus 44 ± 14% in the conventionally treated group (P10−5). This preservation of left ventricular function was observed both in patients with anterior and in those with inferior infarction. Thombolysis by the intracoronary route has the potential for myocardial salvage; however, the expected benefit on early and late mortality has not yet been demonstrated and this will require the inclusion of a larger number of patients.