Ventilator-Associated Pneumonia and PaO2/FIO2 Diagnostic Accuracy: Changing the Paradigm?

BACKGROUND: Ventilator-associated pneumonia (VAP) is associated to longer stay and poor outcomes. Lacking definitive diagnostic criteria, worsening gas exchange assessed by PaO2/FIO2 ≤ 240 in mmHg has been proposed as one of the diagnostic criteria for VAP. We aim to assess the adequacy of PaO2/FIO2 ≤ 240 to diagnose VAP. METHODS: Prospective observational study in 255 consecutive patients with suspected VAP, clustered according to PaO2/FIO2 ≤ 240 vs. > 240 at pneumonia onset. The primary analysis was the association between PaO2/FIO2 ≤ 240 and quantitative microbiologic confirmation of pneumonia, the most reliable diagnostic gold-standard. RESULTS: Mean PaO2/FIO2 at VAP onset was 195 ± 82; 171 (67%) cases had PaO2/FIO2 ≤ 240. Patients with PaO2/FIO2 ≤ 240 had a lower APACHE-II score at ICU admission; however, at pneumonia onset they had higher CPIS, SOFA score, acute respiratory distress syndrome criteria and incidence of shock, and less microbiological confirmation of pneumonia (117, 69% vs. 71, 85%, p = 0.008), compared to patients with PaO2/FIO2 > 240. In multivariate logistic regression, PaO2/FIO2 ≤ 240 was independently associated with less microbiological confirmation (adjusted odds-ratio 0.37, 95% confidence interval 0.15-0.89, p = 0.027). The association between PaO2/FIO2 and microbiological confirmation of VAP was poor, with an area under the ROC curve 0.645. Initial non-response to treatment and length of stay were similar between both groups, while hospital mortality was higher in patients with PaO2/FIO2 ≤ 240. CONCLUSION: Adding PaO2/FIO2 ratio ≤ 240 to the clinical and radiographic criteria does not help in the diagnosis of VAP. PaO2/FIO2 ratio > 240 does not exclude this infection. Using this threshold may underestimate the incidence of VAP.info:eu-repo/semantics/publishedVersio

Layout level design for testability strategy applied to a CMOS cell library

The layout level design for testability (LLDFT) rules used here allow to avoid some hard to detect faults or even undetectable faults on a cell library by modifying the cell layout without changing their behavior and achieving a good level of reliability. These rules avoid some open faults or reduce their appearance probability. The main purpose has been to apply that set of LLDFT rules on the cells of the library designed at the Centre Nacional de Microelectronica (CNM) in order to obtain a highly testable cell library. The authors summarize the main results (area overhead and performance degradation) of the application of the LLDFT rules on the cell

Farmland transfers in KwaZulu-Natal, 1997-2003: A focus on land redistribution including restitution

Census surveys of land transactions show that 203,300 hectares of KwaZulu-Natal's commercial farmland transferred to previously disadvantaged South Africans over the period 1997-2003. This represents 3.8 per cent of the farmland originally available for redistribution in 1994. The annual rate of land redistribution in the province fell from a peak of 1.06 per cent in 2002 to 0.41 per cent in 2003, following an increase in the real price of farmland. Transactions financed only with government grants accounted for almost one-half of the redistributed farmland. However, the quality of farmland financed with grants awarded under government's land redistribution programme was poor relative to that financed privately. The LRAD programme introduced in 2001 improved government's contribution to land reform, attracting private capital and expertise into the process. Unfortunately, the number of transactions financed with a combination of LRAD grants and mortgage loans fell from 14 in 2002 to just six in 2003. It is recommended that all reputable banks (and not just the Land Bank) should be allowed to approve LRAD grants for eligible clients. Previously disadvantaged women gained less land, and much less land wealth, than did their male counterparts. Somewhat surprisingly, women were well represented in transactions financed by Ithala Finance and Investment Corporation to establish emerging sugarcane farmers. However, the same was not true of clients financed by the Land Bank.Land Economics/Use,

The Hubbard Dimer: A density functional case study of a many-body problem

This review explains the relationship between density functional theory and strongly correlated models using the simplest possible example, the two-site Hubbard model. The relationship to traditional quantum chemistry is included. Even in this elementary example, where the exact ground-state energy and site occupations can be found analytically, there is much to be explained in terms of the underlying logic and aims of Density Functional Theory. Although the usual solution is analytic, the density functional is given only implicitly. We overcome this difficulty using the Levy-Lieb construction to create a parametrization of the exact function with negligible errors. The symmetric case is most commonly studied, but we find a rich variation in behavior by including asymmetry, as strong correlation physics vies with charge-transfer effects. We explore the behavior of the gap and the many-body Green's function, demonstrating the `failure' of the Kohn-Sham method to reproduce the fundamental gap. We perform benchmark calculations of the occupation and components of the KS potentials, the correlation kinetic energies, and the adiabatic connection. We test several approximate functionals (restricted and unrestricted Hartree-Fock and Bethe Ansatz Local Density Approximation) to show their successes and limitations. We also discuss and illustrate the concept of the derivative discontinuity. Useful appendices include analytic expressions for Density Functional energy components, several limits of the exact functional (weak- and strong-coupling, symmetric and asymmetric), the Kohn-Sham hopping energy functional for 3 sites, various adiabatic connection results, proofs of exact conditions for this model, and the origin of the Hubbard model from a minimal basis model for stretched H$_2$

Choice-Nash Equilibria

We provide existence results for equilibria of games where players employ abstract (non binary) choice rules. Such results are shown to encompass as a relevant instance that of games where players have (non-transitive) SSB (Skew-Symmetric Bilinear) preferences, as will as other well-known transitive (e. g. Nash´s) and non-transitive (e. g. Shafer and Sonnenschein´s) models in the literature. Further, our general model contains games where players display procedural rationality.

The spectroscopic orbits and the geometrical configuration of the symbiotic binary AR Pavonis

We analyze optical and near infrared spectra of intermediate and high resolution of the eclipsing symbiotic system AR Pavonis. We have obtained the radial velocity curves for the red and the hot component from the M-giant absorption lines and from the wings of Halpha, H and He II4686 emission profiles, respectively. From the orbital elements we have derived the masses, Mgiant=2.5 and Mhot =1.0 solar masses, for the red giant and the hot component, respectively. We also present and discuss radial velocity patterns in the blue cF absorption spectrum as well as various emission lines. In particular, we confirm that the blue absorption lines are associated with the hot component. The radial velocity curve of the blue absorption system, however, does not track the hot companion's orbital motion in a straightforward way, and its departures from an expected circular orbit are particularly strong when the hot component is active. We suggest that the cF-type absorption system is formed in material streaming from the giant presumably in a region where the stream encounters an accretion disk or an extended envelope around the hot component. The broad emission wings originate from the inner accretion disk or the envelope around the hot star.We also suggest that the central absorption in H profiles is formed in a neutral portion of the cool giant's wind which is strongly concentrated towards the orbital plane. The nebula in AR Pav seems to be bounded by significant amount of neutral material in the orbital plane. The forbidden emission lines are probably formed in low density ionized regions extended in polar directions and/or the wind-wind interaction zone.Comment: 12 pages, 5 figures, accepted by A&

Measuring the performance of equity-share schemes in South African agriculture: A focus on financial criteria

This study aims to develop a robust methodology for measuring financial performance of equity-share schemes. Several studies have investigated various aspects of performance of these schemes but no single study has yet measured their performance using an objective set of criteria. Four categories of such objective criteria are proposed: poverty alleviation; empowerment and participation; institutional arrangements and governance; and financial performance. This paper focuses only on the financial performance criteria. Recognised indicators of financial performance are applied to balance sheet and income statement data provided by four equity-share schemes in the Western Cape province. This analysis highlights problems with several of the conventional ratios used to measure profitability, solvency and growth when they are applied to recently restructured farming enterprises whose 'empowerment' status attracts exceptionally high levels of debt capital to finance long-term investments. To avoid these problems it is recommended that, for equity-share schemes, profitability should be measured by the return on assets or dividend return; solvency by the debt/asset ratio; liquidity by cash flow projections; growth by changes in the (estimated) real value of shares; and workers' total returns by changes in the sum of the real wage bill, capital gains, dividends, interest and other benefits accruing to workers in aggregate.Agricultural Finance,

Criteria to monitor the poverty alleviation, empowerment and institutional performance of equity-share schemes in South African agriculture

This paper extends a previous study in South Africa aimed at developing methodology for assessing the performance of equity-share schemes. The previous study proposed four broad criteria to measure performance: poverty alleviation; empowerment and participation; institutional arrangements and governance; and financial performance. This paper does not aim to assess the performance of existing equity-share schemes but to develop a methodology for the first three criteria based on empirical analysis of data gathered in 2004 from a land reform project in the Midlands of KwaZulu-Natal and seven established equity-share schemes in the Western Cape. Poverty alleviation is measured using a transition matrix of households grouped by four different symptoms of poverty: current income, wealth, health and a principal component index of housing quality. Eight categories of indicators are recommended for empowerment and participation: control and ownership; skills transfer; understanding; information; outcomes; trust; outreach; and participation. A scorecard applying norms based on empirical evidence gathered at the equity-share schemes in the Western Cape is used to test the indicators. A scorecard approach is also applied to institutional arrangements and governance, which are measured using three categories of indicators: accountability, transparency and property rights. The proposed performance measures are relevant, manageable in number and have feasible norms based on empirical evidence. These indicators and their norms need to be tested on a wider scale and monitored over time. Future research should be undertaken to determine weights for the empowerment and institutional indicators.Food Security and Poverty,