Simple scoring system to predict in-hospital mortality after surgery for infective endocarditis

BACKGROUND: Aspecific scoring systems are used to predict the risk of death postsurgery in patients with infective endocarditis (IE). The purpose of the present study was both to analyze the risk factors for in-hospital death, which complicates surgery for IE, and to create a mortality risk score based on the results of this analysis. METHODS AND RESULTS: Outcomes of 361 consecutive patients (mean age, 59.1\ub115.4 years) who had undergone surgery for IE in 8 European centers of cardiac surgery were recorded prospectively, and a risk factor analysis (multivariable logistic regression) for in-hospital death was performed. The discriminatory power of a new predictive scoring system was assessed with the receiver operating characteristic curve analysis. Score validation procedures were carried out. Fifty-six (15.5%) patients died postsurgery. BMI >27 kg/m2 (odds ratio [OR], 1.79; P=0.049), estimated glomerular filtration rate 55 mm Hg (OR, 1.78; P=0.032), and critical state (OR, 2.37; P=0.017) were independent predictors of in-hospital death. A scoring system was devised to predict in-hospital death postsurgery for IE (area under the receiver operating characteristic curve, 0.780; 95% CI, 0.734-0.822). The score performed better than 5 of 6 scoring systems for in-hospital death after cardiac surgery that were considered. CONCLUSIONS: A simple scoring system based on risk factors for in-hospital death was specifically created to predict mortality risk postsurgery in patients with IE

Universal Ethics: Organized Complexity as an Intrinsic Value

International audienceHow can we think about a universal ethics that could be adopted by any intelligent being, including the rising population of cyborgs, intelligent machines, intelligent algorithms, or even, potentially, extraterrestrial life? We generally give value to complex structures, to objects resulting from long periods of work, and to systems with many elements and with many links finely adjusted. These include living beings, books, works of art, and scientific theories. Intuitively, we want to keep, multiply, and share such structures, as well as prevent their destruction. Such objects have value not because more information (in bits) would simply mean more value. Instead, they have value because they require a long computational history -- assuming that the numerous interactions governing their construction constitute a computation -- and they display what we call organized complexity. To propose the foundations of a universal ethics based on the intrinsic value of organized complexity, we first discuss conceptions of complexity and argue that Charles Bennett's logical depth is a satisfactory notion of what we are looking for. We then put forward three fundamental imperatives: to preserve, augment, and recursively promote organized complexity. We show a broad range of applications with human, nonhuman, and nonliving examples. Finally, we discuss some specific issues of our framework such as the distribution of complexity, the managing of copies and erasures, and how our universal ethics tackles classical ethical issues. In sum, we propose a clear, homogenous, and consistent ethical foundation that can integrate many universal ethics desiderata

Organized Complexity: Is Big History a Big Computation?

The concept of "logical depth" introduced by Charles H. Bennett (1988) seems to capture, at least partially, the notion of organized complexity, so central in big history. More precisely, the increase in organized complexity refers here to the wealth, variety and intricacy of structures, and should not be confused with the increase of random complexity, formalized by Kolmogorov (1965). If Bennett is right in proposing to assimilate organized complexity with "computational content", then the fundamental cause of the increase of complexity in the universe is the existence of computing mechanisms with memory, and able to cumulatively create and preserve computational contents. In this view, the universe computes, remembers its calculations, and reuses them to conduct further computations. Evolutionary mechanisms are such forms of cumulative computation with memory and we owe them the organized complexity of life. Language, writing, culture, science and technology can also be analyzed as computation mechanisms generating, preserving and accelerating the increase in organized complexity. The main unifying theme for big history is the energy rate density, a metric based on thermodynamics. However useful, this metric does not provide much insight into the role that information and computation play in our universe. The concept of "logical depth" provides a new lens to examine the increase of organized complexity. We argue in this paper that organized complexity is a valid and useful way to make sense of big history. Additionally, logical depth has a rigorous formal definition in theoretical computer science that hints at a broader research program to quantify complexity in the universe. Keywords: organized complexity, Kolmogorov complexity, logical depth, big history, cosmic evolution, evolution, complexity, complexification, computation, artificial life, philosophy of informationComment: 10 pages, Published in American Philosophical Association Newsletter on Philosophy and Computers 17, (2) pages 49 to 5

Universal Ethics: Organized Complexity as an Intrinsic Value.

International audienc

Study of the contribution of cobalt additive to the behavior of the nickel oxy-hydroxide electrode by potentiodynamic techniques

Using stepwise potentiodynamic cycling with observations of the chronoamperometric responses, we demonstrated different behaviors for Co additives in nickel oxy-hydroxides electrodes (NOE), depending on their form: either co-precipitated or post-added as a coating. First, we show that for pure Co(OH)2, oxidation occurs at 0.9 V directly in a solid-state process or through a dissolution re-crystallization process, depending on the oxidation rate. Then, we also show that Co(OH)2 post-added in Ni(OH)2 behaves as pure Co(OH)2 whereas when Co is co-precipitated in the Ni(OH)2 synthesis, it has no specific redox signature of its own but it improves the nickel oxy-hydroxide electrode chargeability - making it possible to clearly observe the various redox domains of the NOE around 1.3 V vs. Cd-Cd(OH)2. Then, such a technique could be used as a probe to determine - depending on the potential (Vox) at which the Co(II) to Co(III) oxidation occurs - whether cobalt was simply added, coated (Vox=0.9 V) or co-precipitated (Vox=1.3 V) into the nickel oxy-hydroxide electrode. Finally, it is shown that using appropriate cut-off potential upon reduction, one can follow possible changes in the Co additive situation upon long-term cycling of NOE. © 2002 Elsevier Science B.V. All rights reserved

The outcome of cobalt in the nickel-cobalt oxyhydroxide electrodes of alkaline batteries

The evolution of cobalt hydroxide used as a coating for nickel hydroxide electrodes has been studied as a function of the redox potential window and upon cycling. From both chemical and electrochemical studies, it is shown that (i) upon deep discharges cobalt tends to migrate from the coating to the current collector and (ii) upon heavy cycling in the limited 1-1.4 V potential range a complete reorganization of the active material occurs. In the latter case, using X-ray diffraction, electron microscopy, and potentiodynamic intermittent technique, we identified the formation of a Ni1-xCox(OH)2(CO3)z ·rH2O-type phase through dissolution reprecipitation processes involving both cobalt and nickel species. From these findings, the conditions required to preserve the benefits of cobalt additives are given. © 2001 Elsevier Science

Oxidation mechanism of cobalt hydroxide to cobalt oxyhydroxide

Although cobalt hydroxide is currently added to Ni(OH)2 paste to prepare nickel composite electrodes used in Ni-based rechargeable alkaline batteries, its redox chemistry in alkaline media is still poorly documented. The Co(OH)'2→CoOOH oxidation reaction in KOH media was investigated, and found to be dependent upon the experimental conditions, namely, temperature, oxidizing agent and reaction time. In addition, this reaction was shown, as determined by means of X-ray diffraction, electronic microscopy and atomic absorption measurements, to occur through a two step mechanism process involving first a dissolution process followed by a solid state reaction. This dissolution step enables preparation, by adjusting the cycling conditions, of cobalt oxyhydroxide with well defined morphology and texture, thereby providing an opportunity to optimize its efficiency as an additive in nickel electrodes