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We consider the problem of estimating the parameter $\fnl$ in the standard local model of primordial CMB non-Gaussianity. We determine the properties of maximum likelihood (ML) estimates and show that the problem is not the typical ML estimation problem as there are subtle issues involved. In particular, The Cramer-Rao inequality is not applicable and the likelihood function is unbounded with several points of maxima. However, the particular characteristics of the likelihood function lead to ML estimates that are simple and easy to compute. We compare their performance to that of moment estimators. We find that ML is better than the latter for values $\fnl$ away from the origin. For small values of $\fnl$, the fifth order moment is better than ML and the other moment estimators. However, we show how for small $\fnl$, one can easily improve the estimators by a simple shrinkage procedure. This is clearly important when the goal is to estimate a very small $\fnl$. In the process of studying the inference problem, we address some basic issues regarding statistical estimation in general that were raised at the Workshop on Non-Gaussianity in Cosmology held in Trieste in July 2006., Comment: 15 pages including 6 figures

Reimplantation disease (RD) is a postoperative complication in lung transplantation. It is defined as hypoxemia (PaO2/FiO2 ratio150 mmHg), radiologic infiltrates and decrease of lung compliance. The aim of the study was to analyze the incidence, predictive factors, prognosis and outcome of the patients with RD.49 patients submitted to lung transplantation (June 1991-December 1996) were admitted in our intensive care unit (ICU). Donor and recipient conditions, surgical parameters and outcome in ICU were analyzed. Mann-Whitney, Kruskall-Wallis, Fisher, Pearson and ANOVA-Friedman tests were used for statistical analysis according to the different variables.49% of the patients (29/49) developed RD, which was influenced neither by lung disease, nor by the kind of transplantation or by ischemia time. All patients with a long surgical time developed RD, versus only 41% in those where surgery was undertaken in a shorter period of time, OR: 2.8 (1.5-5.7; p = 0.0016). The patients with RD improved showing a PaO2/FiO2 ratio of 176 and 235 mmHg at 24 and 48 h respectively (ANOVA, p0.00001). The patients with RD needed 14 days of mechanical ventilation versus 7 days in those without RD (p = 0.013). There were no statistically significant differences in stay and mortality in ICU.RD is a common complication in the postoperative phase of lung transplantation. It is present in almost all the patients with long surgical time. Almost all of them improve, with the same survival but a longer period of mechanical ventilation.

The sky-RMS is the simplest model-independent characterization of a cosmological anisotropy signal. The RMS temperature fluctuations determined from the $COBE$-DMR four-year sky maps are frequency independent, consistent with the hypothesis that they are cosmological in origin, with a typical amplitude at 7 degrees of ~ 35 \pm\ 2 uK and at 10 degrees of ~29 \pm\ 1 uK. A joint analysis of the 7 deg and 10 deg "cross"-RMS derived from the data in both Galactic and Ecliptic coordinates is used to determine the RMS quadrupole normalization, $Q_{rms-PS}$, for a scale-invariant Harrison-Zel'dovich power law model. The difference in the inferred normalizations either including or excluding the quadrupole is a consequence of the sensitivity of the method to the Galaxy contaminated observed sky quadrupole. Whilst there are variations depending on the data selection, all results are consistent with an inferred \qrms\ normalization of ~18 \pm\ 2 uK., Comment: 14 pages, submitted to The Astrophysical Journal (Letters)

Equation (1) and the numbers in table 1 can be used to correct the published values of Qrms. For non-uniform sampling, instrument noise and Galactic cut the corrections correspond to the sum in quadrature of the Gould and Stark adjustment (Table 4 in [St]). Out corrections Q(σi) are about 25% smaller than those of Stark. The corrections due only to noise are about 10% smaller than those in [Gd].

The frequency-independent RMS temperature fluctuations determined from the COBE-DMR two year sky maps are used to infer the parameter Q_{rms-PS}, which characterizes the normalization of power law models of primordial cosmological temperature anisotropy. In particular, a 'cross'-RMS statistic is used to determine Q_{rms-PS} for a forced fit to a scale-invariant Harrison-Zel'dovich (n = 1) spectral model. Using a joint analysis of the 7 degree and 10 degree RMS temperature derived from both the 53 and 90 GHz sky maps, we find Q_{rms-PS} = 17.0^{+2.5}_{-2.1} uK when the low quadrupole is included, and Q_{rms-PS} = 19.4^{+2.3}_{-2.1} uK excluding the quadrupole. These results are consistent with the n = 1 fits from more sensitive methods (e.g. power spectrum, correlation function). The effect of the low quadrupole derived from the COBE-DMR data on the inferred Q_{rms-PS} normalization is investigated. A bias to lower Q_{rms-PS} is found when the quadrupole is included. The higher normalization for a forced n = 1 fit is then favored by the cross-RMS technique. As initially pointed out in Wright et al. (1994a) and further discussed here, analytic formulae for the RMS sky temperature fluctuations will NOT provide the correct normalization amplitude., Comment: 15 pages including 3 tables and 3 figures, uuencoded Postscript; Accepted for publication in The Astrophysical Journal; COBE Preprint 94-16

Since 1983 unilateral lung transplantation has become a clinical reality. The initial experience of the Hospital General Universitario de la Vall d'Hebron is presented with the description of the two first unipulmonary transplants. The first was a 20 year-old woman with idiopathic pulmonary fibrosis in whom a left unipulmonary transplant was carried out and who, at present is at home following the 23rd postoperative month. The second case was a 27 year-old man with pneumoconiosis who, at 12 months following the left lung transplantation, carries on a normal life. Among the complications observed, the presence of pneumonitis by cytomegalovirus in both patients is of note. Stenosis and partial dehiscence of the bronchial suture in the first patient and isolation of syncitial respiratory virus in the second patient were also observed. The effort and integration into a normal life style of the second patient is excellent. In contrast, the first patient presents an important postoperative functional deterioration secondary to her complications. The present study demonstrates that unipulmonary transplantations is a reality in Spain which must be considered by all respiratory disease specialists in their daily clinical practise.

We present a determination of the cosmic microwave background dipole amplitude and direction from the COBE Differential Microwave Radiometers (DMR) first year of data. Data from the six DMR channels are consistent with a Doppler-shifted Planck function of dipole amplitude Delta T = 3.365 +/-0.027 mK toward direction (l,b) = (264.4 +/- 0.3 deg, 48.4 +/- 0.5 deg). The implied velocity of the Local Group with respect to the CMB rest frame is 627 +/- 22 km/s toward (l,b) = (276 +/- 3 deg, 30 +/- 3 deg). DMR has also mapped the dipole anisotropy resulting from the Earth's orbital motion about the Solar system barycenter, yielding a measurement of the monopole CMB temperature at 31.5, 53, and 90 GHz, to be 2.75 +/- 0.05 K.

In this paper we consider reduced basis approximation and a posteriori error estimation for linear functional outputs of affinely parametrized linear and non-linear parabolic partial differential equations. The essential ingredients are Galerkin projection onto a low-dimensional space associated with a smooth ``parametric manifold'' --- dimension reduction; efficient and effective Greedy and POD-Greedy sampling methods for identification of optimal and numerically stable approximations --- rapid convergence; rigorous and sharp a posteriori error bounds (and associated stability factors) for the linear-functional outputs of interest --- certainty; and Offline-Online computational decomposition strategies --- minimum marginal cost for high performance in the real-time/embedded (e.g., parameter estimation, control) and many-query (e.g., design optimization, uncertainty quantification, multi- scale) contexts. In this paper we first present reduced basis approximation and a posteriori error estimation for general linear parabolic equations and subsequently for a nonlinear parabolic equation, the incompressible Navier-- Stokes equations. We then present results for the application of our (parabolic) reduced basis methods to Bayesian parameter estimation: detection and characterization of a delamination crack by transient thermal analysis.