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In this paper we study the fractional Lagrangian of Pais-Uhlenbeck oscillator. We obtained the fractional Euler-Lagrangian equation of the system and then we studied the obtained Euler-Lagrangian equation numerically. The numerical study is based on the so-called Grunwald-Letnikov approach, which is power series expansion of the generating function (backward and forward difference) and it can be easy derived from the Grunwald- Letnikov definition of the fractional derivative. This approach is based on the fact, that Riemman-Liouville fractional derivative is equivalent to the Grunwald-Letnikov derivative for a wide class of the functions.

It is unquestionable that the concept of entropy has played an essential role both in the physical and biological sciences. However, the entropy production, crucial to the second law, has also other features not clearly conceived. We all know that the main difficulty is concerned with its quantification in non-equilibrium processes and consequently its value for some specific cases is limited. In this work we will review the ideas behind the entropy production concept and we will give some insights about its relevance.

Resumen Fundamento y objectivos Pocos trabajos han valorado el riesgo especifico de infeccion urinaria bacteriemica por Escherichia coli productor de betalactamasas de espectro extendido (BLEE). Pacientes y metodos Serie de casos retrospectiva de todos los pacientes con infeccion urinaria bacteriemica por E. coli atendidos en nuestro centro durante el 2006. Resultados Se aislo BLEE en 19 casos (17,9%) de 106 bacteriemias de foco urinario. Los pacientes con bacteriemia por BLEE eran predominantemente varones, de mayor edad, procedentes de residencia de ancianos, con enfermedad urologica previa y manipulacion urologica mas frecuente, con mayor uso de antibiotico previo, con porcentaje mas alto de infecciones urinarias previas, mayor frecuencia de infeccion nosocomial e ingreso en el mes previo. En la regresion logistica, resultaron variables independientes predictoras de infeccion urinaria bacteriemica por BLEE la enfermedad urologica previa (odds ratio [OR]: 13,9, intervalo de confianza [IC] del 95%: 2,5–8,2) y estar institucionalizado en residencia (OR: 6,5, IC del 95%: 1,4–30,9). Conclusiones La enfermedad urologica previa y estar institucionalizado en residencia son factores de riesgo independientes para presentar infeccion urinaria bacteriemica por BLEE.

The Chapman mechanism is the simplest photochemical mechanism to understand the formation of ozone in stratospheric conditions. In this paper we apply the Poincare compactification to the dynamical system generated by the above mechanism. We analyze the critical points both in the finite part and at infinity, and find the heteroclinic connections among them, getting in this way a complete qualitative analysis of the global flow.

Summary Background COPD is a prevalent disease that generates high use of resources. The objective of this study was to quantify the economic consequences of non-adherence to GOLD guidelines for the management of COPD patients. Method An economic model was generated to compare different scenarios of observed vs. expected costs of COPD treatment. A pooled analysis of data derived from a systematic review of studies describing treatment of COPD in Spain was combined with drug costs (using different assumptions) to obtain the observed cost of COPD treatment. An expected cost was obtained with the minimum and maximum treatment intensity derived from the GOLD recommendations. Results A total of 8 studies were identified, comprising 6339 patients. Average medication cost of COPD patients was estimated as being between €1218 and €1314 per patient per year, higher than the ideal expected average cost (between €1007 and €1021 per patient/year). Thus, implementation of guidelines would result in a mean reduction of €198–€293 per patient/year. Sensitivity analysis showed that about 13% of patients had higher treatment costs than the maximum expected cost. This proportion is much higher in moderately/severely affected patients than in mildly affected patients (28.0% and 11.1%, respectively). Conclusions Treatment of COPD allows for the identification of areas of inefficiency. An improvement in the adherence to the GOLD guidelines would imply potential savings of medication costs of about 20% of the observed costs.

Introduction: The optimal timing for initiation of highly active antiretroviral therapy (HAART) in patients with AIDS and tuberculosis (TB) is an unresolved question. To assess the effect of HAART on the survival of patients with TB, we designed this study. Methods: We selected all HIV patients included in the COMESEM cohort with TB diagnosis after 1996. Clinical and epidemiological data were registered. We compared patients who started HAART at the diagnosis of TB [simultaneous therapy (ST)] or not. Survival was assessed by Cox analysis. Results: Among the 6934 HIV patients included in the cohort, 1217 patients had TB, 322 of them (26.5%) after 1996. At the time of TB diagnosis, 45% of them started HAART (ST). There were no differences between groups regarding basal characteristics, except for a lower viral load in ST patients. ST therapy was associated with improved survival (hazard ratio 0.38; 95% confidence interval 0.20 to 0.72, P = 0.003). By univariate analysis, survival was also associated with no endovenous drug use and a later year of TB diagnosis. After adjusting for other prognostic variables, by Cox multivariate analysis, ST remained robustly associated with improved survival (hazard ratio 0.37; 95% confidence interval 0.17 to 0.66, P = 0.001). Conclusions: Simultaneous HAART and TB treatment in HIV patients with TB is associated with improved survival.

The molecular epidemiology and the mechanisms of resistance of Escherichia coli isolated from two patients infected by imipenem-resistant strains are reported in this study. From one patient, three closely related consecutive isolates of E. coli were recovered; the first was carbapenem-susceptible but acquired imipenem resistance after treatment with ertapenem, and the third isolate was again imipenem-susceptible. An additional imipenem-resistant isolate was recovered from another patient who received imipenem. The genetic relatedness of the E. coli isolates was determined by pulsed-field gel electrophoresis (PFGE) after digestion with XbaI. Standard polymerase chain reaction (PCR) conditions were used to amplify several beta-lactamase genes coding for carbapenemases, extended-spectrum beta-lactamases (ESBLs) and plasmid-mediated AmpC; the E. coli ampC gene promoter was also amplified and sequenced. Primers OmpF-F/OmpF-R and OmpC-F/OmpC-R were used to amplify the ompF and ompC genes. The outer membrane protein (OMP) profiles were studied by sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE). Imipenem-resistant E. coli isolates did not produce carbapenemases but lacked the two major OMPs OmpF and OmpC and had ampC promoter mutations; in addition, one of the imipenem-resistant isolates produced the CMY-2 cephalosporinase, whilst the other produced the new CTX-M-67 ESBL. Carbapenem resistance in this study was associated with lack of expression of OmpF and OmpC porins. Additional mechanisms of beta-lactam resistance, such as plasmid-mediated AmpC and ESBL production, were also found. Development of carbapenem resistance in a CTX-M-67-producing E. coli is first described in this study.

The kinetic theory for traffic flow equations can be approached using the Grad's method. This method, which is derived from the kinetic gas theory, was developed for the Paveri-Fontana equation when a special desired velocity model is assumed. A closure relation for the set of macroscopic equations is found when the density, the average velocity and the velocity variance are the relevant variables chosen to describe the system. Simulation results are also shown and a qualitative comparison with other models in the literature is presented.

This work is mainly concerned with the extension of hydrodynamics beyond the Navier–Stokes equations, a regime known as Burnett hydrodynamics. The derivation of the Burnett equations is considered from several theoretical approaches. In particular we discuss the Chapman–Enskog, Grad’s method, and Truesdell’s approach for solving the Boltzmann equation. Also, their derivation using the macroscopic approach given by extended thermodynamics is mentioned. The problems and successes of these equations are discussed and some alternatives proposed to improve them are mentioned. Comparisons of the predictions coming from the Burnett equations with experiments and/or simulations are given in order to have the necessary elements to give a critical assessment of their validity and usefulness.

The most known macroscopic equations for traffic flow are reviewed from a unified point of view. The analysis is done taking into account their origin, historical development and the results coming from the different treatments. We consider mainly models which describe traffic flow by means of up to three evolution equations for macroscopic variables.

Las tomografias computarizadas multidetectores comienzan a generalizarse en los hospitales y con ellas la posibilidad de realizar estudios cardiacos. La tecnica es tecnico-dependiente y es necesario conocer ciertas consideraciones que ayudaran a mejorar el resultado del estudio. Se resumen en cuatro puntos. La preparacion del paciente para decidir si usaremos bloqueadores beta o no, aspectos en el uso rutinario del vasodilatador, algunas normas para ensayar la apnea del paciente, etc. La segunda parte se centra en la adquisicion, cuando usar una adquisicion con multisegmentacion o la posibilidad incluso de hacer estudios con adquisicion prospectiva que disminuye la dosis de radiacion. La tercera esta referida a la administracion de contraste para conseguir un buen realce en los vasos. El ultimo apartado resume las tecnicas de postprocesado, y se comentan los posibles errores con las reconstrucciones 3D o la necesidad de hacer una reconstruccion que abarque todo el torax para despistar otras patologias.

The clinical manifestations of HIV infection vary widely in distinct geographical areas. While HIV-related disease has been well characterized in western countries, relatively few publications have described the clinical manifestations of these diseases in tropical areas, where the vast majority of HIV-infected people are concentrated. In addition, HIV infection may alter the natural history of tropical diseases in several ways and tropical diseases influence the course of HIV infection. The present review describes the major opportunistic infections afflicting people with HIV/AIDS in Africa, Latin America, and Asia and discusses the mutual interactions between HIV and the major tropical diseases.

The photochemical mechanisms behind the ozone dynamics in the stratosphere have been studied for a long time. Though the differential equations describing the kinetics associated with them are well known, their mathematical properties have not been fully explored. In this work some of these mathematical properties as well as their physical implications are investigated in the simplest photochemical mechanism, namely, Chapman’s one.

The aim of the study presented here was to assess the efficacy and tolerability of linezolid in the treatment of orthopedic implant infections (OII). Eighty-five patients with an OII treated with linezolid were prospectively followed up for a minimum of 12 months from the end of antibiotic therapy. Outcome was evaluated in relation to the duration and type of symptoms (acute or chronic) and the retention or removal of the implant. For acute and chronic infections, the respective success rates were 100 and 92.3% when the implant was removed and 72.2 and 42.8% when it was not. The median length of linezolid treatment in acute and chronic infections was 47 and 60 days, respectively. Thrombocytopenia was observed in four (4.7%) patients and anemia in five (5.8%). The results suggest oral linezolid is an effective and well-tolerated alternative for treating OII.

The Burgers equation has been considered in a phenomenological way to describe some characteristics of traffic flow. With a special model for the desired velocity of drivers, we have derived it from the Reduced Paveri-Fontana equation by means of the maximization of the informational entropy and an approximation method which introduces a relaxation time associated to the collective behaviour.

La aparicion de la tomografia computarizada (TC) helicoidal en la decada de los anos noventa supuso el salto tecnologico para obtener imagenes en distintos planos del espacio. Esto se debio a la adquisicion volumetrica, es decir, el tubo de rayos X mantenia la exposicion mientras la mesa se movia de forma continua. La posibilidad de aumentar el numero de detectores favorecia la rapidez al obtener varias imagenes (4, 16, 40 o 64) en cada giro del tubo. Asi se estudia un volumen (torax o abdomen) con mejor resolucion espacial e imagenes muy finas: 0,5 mm. La resolucion temporal, que es el tiempo para obtener una imagen, mejoro significativamente debido a la mayor velocidad en el giro del tubo. Sin embargo, en el estudio del corazon se precisa tambien la sincronizacion con el ciclo cardiaco para adquirir las imagenes en la zona telediastolica, lo que posibilita no solo la visualizacion de las arterias coronarias, sino tambien la valoracion de los bypass, stents, anomalias coronarias e incluso el estudio de la funcion ventricular.

El presente artículo analiza los discursos que se esgrimieron en las principales cabeceras de la prensa española sobre el referéndum por la independencia de Escocia. Utilizando como técnica el análisis de contenido cualitativo, el objetivo primordial de este estudio es examinar cómo fue representado el debate que generó el 18 de septiembre, así como las comparaciones argumentales que los diarios realizaron entre la cuestión independentista escocesa y catalana. La investigación que se presenta explora un campo novedoso y abre nuevas áreas de trabajo sobre el nacionalismo, el independentismo y el papel de los medios en la conformación de opiniones.

Resumen La limitacion de esfuerzos terapeuticos es una medida escasamente evaluada en nuestro medio. Se valoran las caracteristicas de los pacientes en los que se retiran los antibioticos en presencia de una infeccion activa. Se recogieron datos de todos los pacientes ancianos ingresados consecutivamente en medicina interna con infeccion activa a los que se les suspendia el antibiotico. Se compararon las caracteristicas de los pacientes que fallecieron y de los que no. En el estudio se incluyo a 63 pacientes (8,9% de los ingresos); 84,6 ± 9,1 anos. Un 86% tenia demencia, un 73%, incapacidad, y un 30%, neoplasia activa. El motivo de la retirada de los antibioticos fue siempre la percepcion de una muerte cercana y/o la falta de respuesta al tratamiento. La mortalidad fue del 89%. Entre los que fallecieron, predomino el sexo femenino (el 95 frente al 76%) y tanto el tiempo sin antibiotico (2,9 frente a 8,5 dias) como la estancia media (9,6 frente a 16,0 dias) fueron mas breves (p

Objective To determine the expression of the scavenger receptor, class B, type I (SR-BI) in human granulosa cells. Design Prospective cohort analysis. Setting Tertiary academic university hospital. Patient(s) Women undergoing IVF treatment. Intervention(s) Granulosa cells were isolated from oocyte retrievals. Main Outcome Measure(s) Total RNA and cell lysates were isolated from the granulosa cells, and SR-BI RNA and protein expression were quantified by real-time polymerase chain reaction and western blotting, respectively. Baseline and peak E 2 levels were drawn before IVF treatment and before hCG stimulation. Result(s) The expression of SR-BI RNA and protein were positively correlated. The prevalence of low SR-BI RNA expression (defined as below 25th percentile) was 26%, whereas the prevalence of high SR-BI expression (defined as above 75th percentile) was 24%. Expression of SR-BI RNA was not correlated with body mass index, age, race or ethnicity, primary diagnosis of infertility, or pregnancy outcomes. However, baseline and peak E 2 levels were significantly lower in subjects with low SR-BI RNA expression as compared with subjects with high SR-BI expression ( P P P Conclusion(s) Scavenger receptor–BI is expressed in human granulosa cells. Subjects with low SR-BI expression had lower baseline and peak E 2 levels and lower number of retrieved and fertilized oocytes.

Objetivo: Realizar un analisis de coste-efectividad comparando escitalopram y citalopram en el tratamiento de la depresion mayor grave. Metodologia: Se ha adaptado un modelo de arbol de decision, que representa el tratamiento de la depresion mayor grave, al contexto espanol. El modelo representa las opciones terapeuticas habituales, en el contexto sanitario espanol, para la poblacion del estudio. El horizonte temporal del modelo es de 6 meses y calcula el cociente de coste-efectividad por paciente con remision. Los datos de eficacia del modelo provienen de un ensayo clinico aleatorizado. Las pautas de tratamiento habituales en Espana han sido indicadas por varios especialistas medicos. La perspectiva del analisis es la del sistema sanitario y el ano del analisis, 2005. Resultados: El coste por paciente con remision es de 951 € con escitalopram y de 992 € con citalopram. El coste por conseguir una remision adicional mediante escitalopram respecto a citalopram se ha estimado en 353 €. Conclusiones: El tratamiento con escitalopram, ademas de ser mas eficaz que citalopram, presenta un perfil de eficiencia cuyos costes adicionales respecto de los costes de los tratamientos medios por remision con citalopram son menores, por lo que su empleo estaria respaldado desde la perspectiva economica.

Objetivo. Realizar un analisis coste-efectividad de samario [153Sm-EDTMP] (Quadramet®) respecto a la terapia convencional, para el tratamiento del dolor causado por metastasis oseas en pacientes con cancer de prostata.

Tourism is one of the world’s largest industries and a key sector in Spain. Tourism has become part of governmental programmes since its development in the country, and the Spanish Government has developed a specific tourism public policy since 1978. Nevertheless, tourism is a controversial issue that involves different types of positive and negative impacts. The aim of this article is to analyse the relationship between the Legislature and governmental tourism policy by exploring the extent to which the parliamentary groups –and, especially, the opposition– have had an impact in the policy design process. Even if it is commonly assumed that legislatures play a relatively residual role in the process of policy formulation, our aim is to empirically assess the degree to which this is really the case for tourism policies in Spain. The most significant conclusions of our study are that in Spain we find a high consistency and similarity of the contents of legislative proposals by the parliamentary groups during the last thirty years, and that Parliament has played mostly a reactive (rather than active) role in this field.

A kinetic theory approach is developed from the semiclassical Boltzmann transport equation for the thermotransport of electrons in polar semiconductors in the degenerate limit. The method of moments drives to a set of hydrodynamical equations which are closed up to thirteen relevant variables, including the stress tensor and the heat flux in the description. The closure of the balance equations is achieved by evaluating the higher order momenta, as well as the production terms, through a nonequilibrium Fermi–Dirac distribution function coming from the maximum entropy principle. Our main results are a set of characteristic relaxation times, which are evaluated under the consideration that electron–optical polar phonon interaction is the leading scattering process. Also, under degenerate conditions analytical expressions are obtained for the relaxation times and the usual thermoelectric coefficients.

Radiological study of coronary arteries has undergone major advances, especially with the incorporation of new CT multidetectors which afford temporary spatial resolution sufficient for the acquisition of high-quality images and diagnoses concerning various coronary artery abnormalities. The technique is described in terms of both facilitating data within a procedure making use of beta-blockers to slow heart rate and postprocess image reconstruction. Accordingly, our experience with a 16-detector CT and its clinical applications are illustrated.

To assess the utility of blood cultures in the management of uncomplicated pyelonephritis in women, we prospectively collected data from 583 cases. Discordant cases were defined as those for which the pathogens isolated from urine and from blood were different. We found that 97.6% of cases were nondiscordant. Clinical and microbiological evolution of infection did not differ between the 2 groups, and no changes of antibiotic therapy were required on the basis of blood culture results. Blood culture may not be routinely required for the evaluation of uncomplicated pyelonephritis in women.

Horcajada JP, Moreno I, Velasco M,Marti´nez JA, Moreno-Marti´nez A, Barranco M,Vila J, Mensa J (Hospital Cli´nic Universitari-IDIBAPS, Barcelona, Spain) Community-acquiredfebrile urinary tract infection in diabetics coulddeserve a different management: a case–controlstudy. J Intern Med 2003; 254: 280–286.Objective. To investigate if there are relevantdifferences in clinical, microbiological and outcomecharacteristics of community-acquired febrileurinary tract infection (UTI) between diabetic andnondiabetic patients.Design. A prospectively matched case–control study.Setting. An 800-bed tertiary care university-affiliated hospital.Subjects. A total of 108 patients (54 diabetic and 54nondiabetic patients matched by age and gender)admitted between January 1996 and September1999 with febrile UTI.Methods. Clinical, analytical, microbiological andoutcome variables were analysed by means ofMcNemar test (categorical) or Wilcoxon matchedpairs signed rank test (continuous).Results. Mean age (SD) in both groups was 67.9(14.4) years. In comparison with controls, diabeticpatients were more likely to have fever withoutlocalizing symptoms (27% vs. 9%, P £ 0.0001),diminished consciousness level at admission (25%vs. 10%, P ¼ 0.03), aetiological microorganismdifferent from Escherichia coli (17% vs. 0,P ¼ 0.0004), and quinolone-resistant bacteria(17% vs. 3.7%, P ¼ 0.07). Duration of fever afterthe onset of treatment was 1.75 (1) days in diabeticsand 1.5 (1.1) days in nondiabetics (P ¼ 0.17).However, diabetic patients had a longerhospitalization [5.2 (3.3) days] than nondiabetics[3.9 (2.6) days, P ¼ 0.006].Conclusions. In diabetic patients, febrile UTIs haveclinical and microbiological peculiarities that mayhave diagnostic and therapeutic implications.Keywords: case–control study, diabetes, febrileurinary tract infection.

To compare the Macintosh (M), McCoy (MC), Miller (MIL), Belscope (BP) and Lee-Fiberview (LF) laryngoscopes with respect to the grade of laryngeal visualization and the difficulty of intubation.We included 500 patients scheduled to undergo elective surgery and who required tracheal intubation. Patients were randomly assigned to five groups of 100 patients each. Anesthesia was induced intravenously using 1-3 mg.kg(-1) of propofol, fentanyl 1.5 microg.kg(-1) and atracurium 0.5 mg.kg(-1) or suxamethonium 1 mg.kg(-1). The laryngeal view was classified according to Cormack and Lehane. The degree of difficulty with intubation was rated as: Grade 1, intubation easy; Grade 2, intubation requiring an increased anterior lifting force and assistance to pull the right corner of the mouth upwards to increase space; Grade 3, intubation requiring multiple attempts and a curved stylet; Grade 4, failure to intubate with the assigned laryngoscope. Data were examined using analysis of variance, chi(2) or Fisher test, Student's t test and odds ratio. P0.05 was considered statistically significant.Laryngoscopic views obtained with the BP and MIL laryngoscopes were similar, and better than with the other types of laryngoscopes (P0.001). The levering tip of the MC blade (P = 0.02) and the fibreoptic device of the LF (P0.001) significantly improved the laryngoscopic view. Regarding the degree of difficulty with intubation, the best results were obtained with the MC and M blades (P0.001).Laryngoscopy was better with straight blades but curved blades provided better intubating conditions.

Objetivo Revisar y explicar los mecanismos fisiopatologicos que se producen en la genesis y desarrollo de la enfermedad aterosclerotica y su previsible repercusion en el diagnostico por imagen.

The prevalence of hemolysin, type 1 fimbriae, P fimbriae, cytotoxic necrotizing factor-1 (CNF-1), aerobactin, and autotransporter toxin (sat) was analyzed by polymerase chain reaction and phenotypic assays of 42 epidemiologically unrelated Escherichia coli strains causing acute pyelonephritis in women (21 nalidixic acid-susceptible and 21 nalidixic acid-resistant strains) and 58 E. coli strains causing cystitis in women (29 nalidixic acid-susceptible and 29 nalidixic acid-resistant strains). Hemolysin and CNF-1 were less prevalent (P.05) in nalidixic acid-resistant than in nalidixic acid-susceptible E. coli strains from patients with either pyelonephritis (14.3% vs. 52.4%) or cystitis (0% vs. 31.0%). Among E. coli strains causing cystitis, type 1 fimbriae expression was less prevalent (P.05) in the nalidixic acid-resistant group (55.2%) than in the nalidixic acid-susceptible group (86.2%). None of the nalidixic acid-resistant and 20.7% of the nalidixic acid-susceptible strains causing cystitis showed the proteolytic toxin Sat (P.05). These results suggest that resistance to quinolones may be associated with a decrease in the presence or the expression of some virulence factors in uropathogenic E. coli.

In this work we develop a semiclassical kinetic model to construct hydrodynamic equations to study the nonequilibrium behavior of an electron gas in a semiconductor. To describe the system we assume that the Boltzmann transport equation is valid and we solve it in terms of the first 13 moments, which become the basic fields to describe thermotransport in this system. The closure of the transport equations is achieved through an expansion around the nonequilibrium Fermi–Dirac distribution function. The nonconserved variables satisfy relaxation equations and their characteristic times are expressed in kinetic terms. The electric current density and the heat flux can be written as generalized constitutive equations, allowing us to obtain thermotransport coefficients as functions of the frequency, where the relaxation times play a very important role.

En las sociedades occidentales, en las que conviven múltiples paradigmas éticos, los dilemas que plantea la genética son entendidos y resueltos de distintas maneras, según el modo de concebir quién es el ser humano y cuáles son los derechos que avalan su dignidad. En este artículo se estudian los argumentos y los criterios que se ofrecen desde el Magisterio de la Iglesia Católica para tomar conciencia y decidir, conforme a esa visión creyente de la realidad, en los conflictos bioéticos que se generan en esta área del saber.

Introduction The first Ebola virus infected patient outside Africa was diagnosed and treated at Alcorcon Foundation University Teaching Hospital (AFUTH). We describe the integrated management strategy (medical, occupational health, preventive and public health) applied to the case. Methods Descriptive study of health-care management of an unexpected case of Ebola virus disease (EVD) at AFUTH treated on 6 October 2014. We describe the clinical evolution of the patient while he was attended at the Emergency Department, the drawing-up process of the action protocol, the process of training of hospital staff, the administrative management for transferring the patient to the referral centre, and the measures implemented for cleaning, disinfection and management of waste. Qualitative variables are expressed as percentages. Results Our centre designed and updated, from May to October, five versions of the acting and care protocol for patients with EVD. The protocol was in force at the AFUTH when a nursing assistant was attended on 6 October 2014. All preventive, diagnostic and therapeutic measures outlined in the protocol were applied and 206 professionals had received training and information about care procedures with a suspect case. Conclusion Health-care management of an unexpected case of EVD was adequate and there was no secondary cases in our staff as a result. All resources available should be used to fight EVD.

One of the most important objectives in the development of traffic theories is the improvement of traffic conditions. To achieve this goal, it is important a good understanding of multistyle and/or multilane traffic. In this work, we summarize the traffic model presented in Mendez and Velasco (FTC J Phys A Math Theor 46(46):462001, 2013) and additionally include the stability analysis of the same. The presented traffic model considers different driving styles, different vehicle types or both, for a two-classes of vehicles in which a model for the average desired speed is introduced (the aggressive drivers model) (Mendez and Velasco, Transp Res Part B 42:782–797, 2008; Velasco and Marques, Phys Rev E 72:046102, 2005). The kinetic model was solved for the steady and homogeneous state and also we obtained the local distribution function from an information entropy maximization procedure. The macroscopic traffic model is constructed by the usual methods in kinetic theory and a method akin with the Maxwellian iterative procedure is accomplished in order to close the macroscopic model for the mixture, where only the densities are present as relevant quantities. The linear stability analysis is carried out in order to have an insight of the unstable traffic regions of the model, which is very helpful in the numerical solution.

The nonlinear relaxation time and the statistics of the first passage time distribution in connection with the quasideterministic approach are used to detect weak signals in the decay process of the unstable state of a Brownian particle embedded in memory thermal baths. The study is performed in the overdamped approximation of a generalized Langevin equation characterized by an exponential decay in the friction memory kernel. A detection criterion for each time scale is studied: The first one is referred to as the receiver output, which is given as a function of the nonlinear relaxation time, and the second one is related to the statistics of the first passage time distribution.

Quinolone-resistant (QR) Escherichia coli may have lower invasive capacity than does quinolone-susceptible E. coli. To evaluate this, we prospectively collected data regarding all cases of E. coli invasive urinary tract infections (IUTI) in 669 adults admitted to the Infectious Diseases Unit of our hospital during a 3-year period, as well as 10,950 patients with cystitis or asymptomatic bacteriuria who presented to the outpatient clinic during a 1-year period. QR E. coli was isolated in 20% of patients with cystitis, compared with 8% of those with IUTI (P

The generalized hydrodynamic behavior of an Enskog moderately dense gas has been studied mainly through the correlation functions approach. However, the kinetic model based on the Grad's method to solve the Enskog equation seems to be a good alternative to such studies. In this work, we explore the behavior of the generalized transport coefficients and obtain several relationships between Grad's method and the usual Chapman–Enskog scheme. The calculation is developed up to a second order in the density expansion, so we can obtain the complete hydrodynamic limit, also involving the volumetric–thermal effects.

This paper is devoted to a discussion of the profiles of shock waves using the full nonlinear Burnett equations of hydrodynamics as they appear from the Chapman-Enskog solution to the Boltzmann equation. The system considered is a dilute gas composed of rigid spheres. The numerical analysis is carried out by transforming the hydrodynamic equations into a set of four first-order equations in four dimensions. We compare the numerical solutions of the Burnett equations, obtained using Adam's method, with the well known direct simulation Monte Carlo method for different Mach numbers. An exhaustive mathematical analysis of the results offered here has been done mainly in connection with the existence of heteroclinic trajectories between the two stationary points located upflow and downflow. The main result of this study is that such a trajectory exists for the Burnett equations for Mach numbers greater than 1. Our numerical calculations suggest that heteroclinic trajectories exist up to a critical Mach number ( approximately 2.69) where local mathematical analysis and numerical computations reveal a saddle-node-Hopf bifurcation. This upper limit for the existence of heteroclinic trajectories deserves further clarification.

In 1982 Bobylev [A.V. Bobylev, Sov. Phys. Dokl. 27, 29 (1982)] made a linear stability analysis of the Burnett equations and showed that beyond a certain critical reduced wave number there exist normal modes that grow exponentially, concluding that the Burnett equations are linearly unstable. We have partially extended his analysis, originally made for Maxwellian molecules, for any interaction potential and argue that his results can be reinterpreted as to give a bound for the Knudsen number above which the Burnett equations are not valid.

Objective To evaluate the clinical and economical impact of the introduction of HIV protease inhibitor (PI) therapy in the current clinical care of HIV-infected patients. Methods Cohort study with 155 HIV-infected patients with a full year of follow-up before and after the introduction of PI by June 1998. The setting was a large urban tertiary teaching hospital in Madrid, Spain. The main outcomes measures were clinical and immunological evolution, pharmacy, out-patient, emergency room and in-patient medical costs evaluated by diagnostic-related group classification, and the global economic costs of clinical care in HIV-infected patients (AIDS and non-AIDS). Results The cost of PI therapy was compensated fully by savings related to reduction of the number, length and severity of hospital admissions in AIDS cases. In contrast, more modest clinical effects with increased costs were observed in non-AIDS cases. Globally, there was an increase of about 20% in the total health-care costs of HIV-infected patients (P

The influence of a boundary layer in the Couette flow of a rarefied gas is studied by means of the Grad's solution for the Boltzmann equation. The boundary conditions satisfied by the relevant Grad's moments are calculated through the simplest wall model which is characterized by some accommodation coefficients in the surface. Accordingly, temperature and velocity profiles in the gas are calculated.

We present the study of a dense gas at a hydrodynamical level of description. We start from the entropy functional obtained at a mesoscopic regime (L. Romero-Salazae et al.; Physica A 237 (1997) 150.) (MEF1) and we apply the Maximum Entropy Formalism where the restrictions are now the hydrodynamic variables and the density fluctuations. An entropy functional is obtained both, in the local and the equilibrium inhomogeneous situation.

Hepatitis due to herpes simplex virus (HSV) is a potentially fatal disorder that is often not considered in the differential diagnosis of acute hepatitis. This disease occurs most often in patients with impaired immunity and is very uncommon in healthy patients. HSV hepatitis presents with a wide clinical spectrum, and the clinical diagnosis is difficult. We describe a case of disseminated herpes virus infection with fulminant hepatitis mimicking an acute human immunodeficiency virus infection in a 33-year-old healthy man. Preliminary studies suggest that early treatment of HSV hepatitis with acyclovir may be beneficial in these patients. A high index of suspicion and the availability of early diagnostic tools, such as HSV DNA detection, may dramatically improve the clinical outcome of severe HSV hepatitis.

The dynamic structure factor as well as the generalized Landau–Placzek relation are calculated from a set of equations describing a monatomic gas in the moderately dense region. These studies start from the 13-moment Grad's approximation to solve the Enskog equation giving us a description of the system which is valid out of the hydrodynamic regime. The hydrodynamic matrix is written in terms of the generalized transport coefficients up to second order in the density, where the bulk viscosity is taken into account.

Coronary aneurysms are uncommon. The most frequent etiologies are atherosclerotic and congenital, although there are several other rare causes. Myocardial infarction and sudden death may be the initial manifestations which are usually a consequence of aneurysm complications such as rupture or distal embolization. Although coronariography is the gold standard diagnostic technique, coronary aneurysm may also be detected by non-invasive methods such as ultrasonography and nuclear magnetic resonance. We report the case of a young male with hypercholesterolemia who presented cardiac arrest as the first clinical manifestation. Ultrasonography and MRI revealed the presence of multiple coronary aneurysm. This case illustrates the usefulness of non-invasive techniques for the diagnosis of coronary aneurysm.

WEB This is a Web exclusive article. assive pulmonary hemorrhage after treatment with antiplatelet drugs is a rare event that can occur in patients with acute coronary syndrome (ACS). The use of medications such as tirofiban (Aggrastat, Merck) and abciximab (ReoPro, Eli Lilly) has been associated with improvement in short-term outcome among patients with ACS who undergo coronary angioplasty [1]. Pulmonary hemorrhage appears as bilateral alveolar infiltrates on chest radiographs and can be easily mistaken for acute pulmonary edema in the context of ACS [2]. When the infiltrates do not resolve with administration of diuretics, the radiologist must be aware of the possibility of pulmonary hemorrhage because early treatment can increase the probability of survival. We report the clinical and radiologic features of a patient with ACS complicated by massive pulmonary hemorrhage due to use of tirofiban.

Fundamento y objetivo Apenas hay datos sobre la incidencia de neumonia en los pacientes infectados por el virus de la inmunodeficiencia humana (VIH) respecto a la poblacion general en la era del tratamiento antirretroviral de gran actividad (TARGA). Pacientes y metodo Se ha realizado un registro prospectivo de las neumonias atendidas en un hospital de zona durante 18 meses. Se comparan las tasas de incidencia entre la poblacion general y los pacientes infectados por el VIH. Resultados En la poblacion general (n = 220.000) la incidencia de neumonia fue de 1,6 casos/1.000 personas/ano, frente a 46 casos/ 1.000 personas/ano en pacientes infectados por el VIH (n = 170) (riesgo relativo = 29,3; intervalo de confianza del 95%, 16,34-51,4; p Conclusiones En la era del TARGA, la incidencia de neumonia en la poblacion infectada por el VIH puede ser unas 30 veces superior a la de la poblacion general, por lo que es necesario reforzar las medidas de prevencion en este tipo de pacientes.