Beta-blocker under-use in COPD patients

Background: Cardiovascular (CVS) comorbidities are common in COPD and contribute significantly to morbidity and mortality, especially following acute exacerbations of COPD (AECOPD). Beta-blockers (BBs) are safe and effective in COPD patients, with demonstrated survival benefit following myocardial infarction. We sought to determine if BBs are under-prescribed in patients hospitalized with AECOPD. We also sought to determine inpatient rates of CVS and cerebrovascular complications, and their impact on patient outcomes. Methods: Retrospective hospital data was collected over a 12-month period. The medical records of all patients 40 years of age coded with a diagnosis of AECOPD were analyzed. Prevalent use and incident initiation of BBs were assessed. Comorbidities including indications and contraindications for BB use were analyzed. Results: Of the 366 eligible patients, 156 patients (42.6%) had at least one indication for BB use – of these patients, only 53 (34.0%) were on BB therapy and 61 (39.1%) were not on BB therapy but had no listed contraindication. Prevalent use of BBs at the time of admission in all 366 patients was 19.7%, compared with 45.6%, 39.6% and 45.9% use of anti-platelets, statins and angiotensin-converting enzyme inhibitor/angiotensin II receptor blockers, respectively. CVS and cerebrovascular complications were common in this population (57 patients, 16%) and were associated with longer length of stay (p,0.01) and greater inpatient mortality (p=0.02). Conclusions: BBs are under-prescribed in COPD patients despite clear indication(s) for their use. Further work is required to explore barriers to BB prescribing in COPD patients

Reweighting for Nonequilibrium Markov Processes Using Sequential Importance Sampling Methods

We present a generic reweighting method for nonequilibrium Markov processes. With nonequilibrium Monte Carlo simulations at a single temperature, one calculates the time evolution of physical quantities at different temperatures, which greatly saves the computational time. Using the dynamical finite-size scaling analysis for the nonequilibrium relaxation, one can study the dynamical properties of phase transitions together with the equilibrium ones. We demonstrate the procedure for the Ising model with the Metropolis algorithm, but the present formalism is general and can be applied to a variety of systems as well as with different Monte Carlo update schemes.Comment: accepted for publication in Phys. Rev. E (Rapid Communications

On the numerical stability of the second barycentric formula for trigonometric interpolation in shifted equispaced points

We consider the numerical stability of the second barycentric formula for evaluation at points in [0,2?] of trigonometric interpolants in an odd number of equispaced points in that interval. We show that, contrary to the prevailing view, which claims that this formula is always stable, it actually possesses a subtle instability that seems not to have been noticed before. This instability can be corrected by modifying the formula. We establish the forward stability of the resulting algorithm by using techniques that mimic those employed previously by Higham (2004, The numerical stability of barycentric Lagrange interpolation. IMA J. Numer. Anal., 24, 547–556) to analyse the second barycentric formula for polynomial interpolation. We show how these results can be extended to interpolation on other intervals of length-2? in many cases. Finally, we investigate the formula for an even number of points and show that, in addition to the instability that affects the odd-length formula, it possesses another instability that is more difficult to correct

Quantified Derandomization of Linear Threshold Circuits

One of the prominent current challenges in complexity theory is the attempt to prove lower bounds for $TC^0$, the class of constant-depth, polynomial-size circuits with majority gates. Relying on the results of Williams (2013), an appealing approach to prove such lower bounds is to construct a non-trivial derandomization algorithm for $TC^0$. In this work we take a first step towards the latter goal, by proving the first positive results regarding the derandomization of $TC^0$ circuits of depth $d>2$. Our first main result is a quantified derandomization algorithm for $TC^0$ circuits with a super-linear number of wires. Specifically, we construct an algorithm that gets as input a $TC^0$ circuit $C$ over $n$ input bits with depth $d$ and $n^{1+\exp(-d)}$ wires, runs in almost-polynomial-time, and distinguishes between the case that $C$ rejects at most $2^{n^{1-1/5d}}$ inputs and the case that $C$ accepts at most $2^{n^{1-1/5d}}$ inputs. In fact, our algorithm works even when the circuit $C$ is a linear threshold circuit, rather than just a $TC^0$ circuit (i.e., $C$ is a circuit with linear threshold gates, which are stronger than majority gates). Our second main result is that even a modest improvement of our quantified derandomization algorithm would yield a non-trivial algorithm for standard derandomization of all of $TC^0$, and would consequently imply that $NEXP\not\subseteq TC^0$. Specifically, if there exists a quantified derandomization algorithm that gets as input a $TC^0$ circuit with depth $d$ and $n^{1+O(1/d)}$ wires (rather than $n^{1+\exp(-d)}$ wires), runs in time at most $2^{n^{\exp(-d)}}$, and distinguishes between the case that $C$ rejects at most $2^{n^{1-1/5d}}$ inputs and the case that $C$ accepts at most $2^{n^{1-1/5d}}$ inputs, then there exists an algorithm with running time $2^{n^{1-\Omega(1)}}$ for standard derandomization of $TC^0$.Comment: Changes in this revision: An additional result (a PRG for quantified derandomization of depth-2 LTF circuits); rewrite of some of the exposition; minor correction

Courtroom Decision Support System Using Case based Reasoning

AbstractThe legal practices in our country have not seen any major changes in terms of technology advancement for decades. While decision support system finding inroads in many other specialized areas, there has been no work done to bring decision support system into legal environment. It is extremely a lengthy waiting period of time to bring a case to court, let alone the whole process of trial until the judgment day. To address this problem, it is suggested to convert our current legal practice into an intelligent based decision support system. A study was conducted by developing a prototype applying a decision support technique to serve as a “virtual courtroom” to plaintiff and defendant in solving their legal cases without the involvement of actual trial. To ensure the system produces fair solutions, case based reasoning was identified as the most suitable technique. This paper proposes the application of case based reasoning in solving legal cases due to the characteristics of the technique which resembles human cognition in solving problems

A conceptual river model to support real-time flood control (Demer River, Belgium)

River engineeringFlow management and contro

Evaluación de Capacidad Adsortiva del Carbón Activado Industrial Darco en Agente Surfactante Dodecil Benceno en Detergentes,realizados en los Laboratorios de Química UNAN-MANAGUA, de Marzo a Noviembre del 2012

Se realizó un estudio experimental evaluando la capacidad adsortiva del carbón activado industrial DARCO, en presencia de agentes surfactantes, Dodecil benceno sulfonato de sodio lineal, presente en la marca de detergente FAB,disuelto en 250 ml de agua. El carbón fue sometido a un proceso de pruebas con el fin de conocer sus propiedades físico-químicas (%ceniza, % de humedad, densidad aparente y porosidad) según las normas de la Sociedad Americana para pruebas y materiales, así como la determinación del porcentaje de remoción y la cuantificación de su capacidad adsortiva Se realizaron ensayos de adsorción en fase liquida con dos tipos de concentraciones una de 80,000 ppm y 40,000 ppm con distintos tiempos de agitación de 30-60 min a una temperatura de 25ºC, el indicador que se empleó para este análisis fue azul de metileno, donde la variable dependiente es la capacidad adsortiva del carbón activado DARCO y las independientes son el tiempo de retención y concentración Para el orden aleatorio de las pruebas fue ajustado por el programa Statgraphcs Plus 5.1 empleando el método multinivel . Para la calibración del Espectrofotómetro Espectrónico Termo de 20 GENESYS serial RS-232-C de UV se realizaron las lecturas de adsorbancia del azul de metileno en una longitud de onda de 652 nm, con el fin de obtener la curva de calibración, lo cual permitió obtener un rango de respuesta lineal para la cuantificación de la adsorbancia del Dodecil benceno sulfonato de sodio lineal. En la adsorción del Dodecil benceno sulfonato de sodio lineal, se determinó que en los dos tiempos de contacto estipulados, el carbón activado presento una gran adsorción ante los dos tipos de concentraciones, el porcentaje de remoción con respecto los tiempos versus concentración osciló entre el 60% y 99%, presente en las muestra. El análisis estadístico que se empleo para comprobar la eficiencia de remoción fue el método de prueba de igualdad de varianza empleando el programa estadístico SPSS, ratificando que no hay diferencia significativa en base a las concentraciones de las muestras de aguas