PDF superior The growth of the $A p$ constant on classical estimates

The growth of the $A p$ constant on
            classical estimates

The growth of the $A p$ constant on classical estimates

The author is very grateful to Professors Eleonor Harboure and Roberto Mac´ıas for the effort they made organizing the CIMPA-UNESCO school on Real Analysis and applications that took place at La Falda, C´ ordoba, Argentina and for the invitation. Also, he is thankful to Professors R. Scotto, J.L. Torrea and A. Bonami for their help and support to make this project possible.

17 Lee mas

A semiparametric Bayesian joint model for multiple mixed type outcomes: an application to acute myocardial infarction

A semiparametric Bayesian joint model for multiple mixed type outcomes: an application to acute myocardial infarction

We propose a Bayesian nonparametric hierarchical model that includes a cluster analysis, aimed at identifying profiles or hospital behaviors that may affect the out- come at patient level. In particular, we introduce a multivariate multiple regression model, where the response has three mixed-type components. The components are, respectively: (1) the door to balloon time (DB), i.e. the time between the admission to the hospital and the PTCA; (2) the in-hospital survival; and (3) the survival after 60 days from admission. The first response (continuous) is essential in quantifying the efficiency of health providers, since it plays a key role in the success of the ther- apy; the second is the basic treatment success indicator, while the third concerns a 60-days period, during which the treatment effectiveness, in terms of survival and quality of life, can be truly evaluated. Note that the last two responses are binary, so that, as a whole, the multivariate response is of mixed type. It is worth noting that the information on patients’ survival after 60 days is obtained from the linkage between STEMI archive and a further administrative database concerning patient-specific vital statistics such as date of birth and death for general causes. The linkage between the different data sources was carried out by Lombardia Informatica S.p.A, the agency managing regional datawarehouses. We do not have direct access to the data sources so as to construct different outcomes of potential interest. Moreover we work with a singly imputed data set and we could not identify data preprocessing tools used by the Lombardia Informatica S.p.A. agency, in particular the technique used to impute the missing data. The modeling of multiple outcomes from data collected in STEMI Archive was previously discussed in Ieva et al. (2014), under a semiparametric fre- quentist bivariate probit model. Their aim was to analyze the relationship among in-hospital mortality and a treatment effectiveness outcome in the presence of con- founders, that is, variables that are associated with both covariates and response. This is a problem that poses serious limitations to covariate adjustment since the use of classical techniques may yield biased and inconsistent estimates. In this context, Ieva et al. (2014) proposed the use of a semiparametric recursive bivariate probit model, as an effective way to estimate the effect that a binary regressor has on a binary outcome in the presence of nonlinear confounder response relationships. In contrast, we focus on a joint model for the grouped outcomes. As discussed below, our aim is to find relevant groups of hospitals in terms of patient-specific characteristics, which may assist in further planning and policy making.
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25 Lee mas

Unbounded Growth in the Ramsey Model with Non-Constant Discounting

Unbounded Growth in the Ramsey Model with Non-Constant Discounting

In his seminal paper, Barro (1999) introduces a varying rate of time preference in a Neoclassical growth model with sophisticated agents to avoid time-inconsistency. 6 The in- stantaneous time discount rate decreases with the time-distance from the present, and it is assumed that it converges towards a positive constant. The consequence of this assump- tion of quasi-hyperbolic discounting is that, the model is observationally equivalent 7 to the standard Neoclassical growth model with a positive constant rate of time preference. In consequence, stagnation is the forced outcome in the long-term if exogenous technological improvements are absent. In this paper, we also consider a sophisticated agent but, unlike Barro (1999), we assume that the instantaneous time discount rate asymptotically declines towards zero. Our assumption means that a present individual does not discount a delay in the very distant future. This hypothesis is already present in the hyperbolic discount functions proposed in the classical psychological literature (Ainslie, 1992). Moreover this property is characteristic of many discount functions proposed in the economic literature on non-constant discounting, like, for example, hyperbolic discounting, proportional dis- counting, power discounting and constant sensitivity (see, Abdellaoui et al. 2010). In a continuous setting, a time-varying discount rate asymptotically converging to zero also ap- pears in the logarithmic discounting proposed by Heal (2007) (and considered by Heal 1998 and Li and Lofgren 2000 to analyze sustainable resource management), and in the regular discounting used by Pezzey (2004) and Farzin and Wendner (2014). Moreover, we assume that the discount function never vanishes, meaning that individuals are not shortsighted in the sense that they do not disregard long-term consequences. Under these assumptions, our model predicts similar results to those of the Neoclassical growth model with a zero time-discount rate.
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31 Lee mas

Stability of magnetic fields in non barotropic stars: an analytic treatment

Stability of magnetic fields in non barotropic stars: an analytic treatment

Before considering the stability, we must first determine the equilibrium structure of the magnetic field. In barotropic stars, the equilibrium form of the magnetic field is severely restricted and is given as the solution of a differential equation (the so-called Grad–Shafranov equation, as discussed, for example, in Chandrasekhar & Fermi 1953; Ferraro 1954; L¨ust & Schl¨uter 1954; Prendergast 1956; a detailed discussion is also given in Akg¨un & Wasserman 2008). On the other hand, in realistic, non-barotropic stars, the hydrostatic force includes a buoyancy term, which acts as a restoring force for stably stratified fluids. Thus, the only restriction that remains for an axisymmetric field in a non-barotropic fluid is that the magnetic force cannot have an azimuthal ( φ) component, since no counterpart exists in the hydrostatic force that can act to ˆ balance it. In addition, the equilibrium magnetic field needs to satisfy boundary conditions at the surface and regularity conditions at the centre of the star. We can construct simple polynomial forms for the scalar functions that describe the poloidal and toroidal components of the magnetic field, consistent with these requirements.
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22 Lee mas

Efecto del bicarbonato de potasio en el crecimiento fúngico y esclerocios de Sclerotium cepivorum y su interacción con Trichoderma

Efecto del bicarbonato de potasio en el crecimiento fúngico y esclerocios de Sclerotium cepivorum y su interacción con Trichoderma

and pH indicated in the previous section were inoculated with PDA disks with mycelium. Trichoderma R39 and Sclerotium cepivorum were placed in opposite sides of the Petri dishes. Sclerotium cepivorum was inoculated first, due to its slow growth, and Trichoderma R39 was placed 24 h later. Fungal cultures were incubated at 20 °C and the growth of both fungi was measured every 24 h for four days. The invasion percentage of Trichoderma over the fungal colony of the pathogen was estimated according to the following equation (Rollan et al., 1999): C=[(DCAP/DSP)x100], where: C=Invasion percentage; DCAP=distance covered by the antagonist on the pathogen colony over the axis which separates both fungi, DSP=distance between sowing points (6.5 cm).
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5 Lee mas

Some Extension of the Bessel Type Orthogonal Polynomials.

Some Extension of the Bessel Type Orthogonal Polynomials.

The structure of the paper is as follows. In Section 2 we list some of the main properties of the classical Bessel polynomials which will be used later on. In Section 3 we dene the generalized polynomials and nd some of their properties. In Section 4 we obtain the representation of the generalized Bessel polynomials in terms of the hypergeometric functions. In Section 5 we obtain an asymptotic formula for these polynomials and in Section 6 we establish their quasi-orthogonality. Finally, in Sections 7 and 8 we obtain the three-term recurrence relation that such polynomials satisfy as well as the corresponding Jacobi matrices.
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17 Lee mas

Analysis of the effect of modulation delays on the size of the output capacitor

Analysis of the effect of modulation delays on the size of the output capacitor

For example, it has been explained that the delay of constant frequency modulation increases the voltage deviation under a loading transient whereas the constant on-time modulation inc[r]

10 Lee mas

“Spectral Triples”

“Spectral Triples”

In the classical case of spin manifolds, the values of the three signs depend only, upon the value of the dimension n modulo 8.. In the classical case of spin manifolds[r]

44 Lee mas

La conversación sobre temas políticos en Twitter: un análisis de la participación y los encuadres interpretativos en el debate sobre la 'Ley Wert' y los desahucios en España

La conversación sobre temas políticos en Twitter: un análisis de la participación y los encuadres interpretativos en el debate sobre la 'Ley Wert' y los desahucios en España

Understanding the frame as an interactive process of social articulation through a shared discourse in specific contexts allows the addressing of sub- jects that are of public interest from two facets: as an expression of interpre- tative schemes and as a symbolic construction process, where the type of par- ticipation plays a fundamental role in the individual cognitive effects (Gam - son and Modigliani, 1989; Gamson et al., 1992). From this perspective, this type of study using frames can contribute to the pondering on the influence of the new processes of production and consumption of information on cu - rrent affairs; about the effects of the social networks on the quality of pu blic debate, and about the transformation that the new arenas for deliberation introduce in the political and media spheres.
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20 Lee mas

Higher order elliptic equations in half space

Higher order elliptic equations in half space

[2] A. P. Calder´ on, Lecture notes on pseudo-differential operators and elliptic boundary value problems. I. Cursos de Matem´ atica, No. 1. Consejo Nacional de Investigaciones Cient´ıficas y T´ ecnicas, Instituto Argentino de Matem´ atica, Buenos Aires, 1976. 89 pp. MR 460947. [3] D. Gilbarg and N. S. Trudinger, Elliptic partial differential equations of second order. Springer-

22 Lee mas

TítuloKinetic and equilibrium study of the reaction of nitroprusside and hydroxide ions: influence of ionic strength using Pitzer Model

TítuloKinetic and equilibrium study of the reaction of nitroprusside and hydroxide ions: influence of ionic strength using Pitzer Model

The mechanism of the reaction between nitroprusside and hydroxide ions is well established [4-6] as well as those of the related processes with the ruthenium and osmium species [13,14]. The reaction takes place through a two-step mechanism: a rate determining attack of a hydroxide at the nitrogen, followed by the removal, by a second hydroxide, of the proton of the complex in a fast acid-base reaction.

19 Lee mas

Sobre la importancia del circunloquio en la clase de lengua española

Sobre la importancia del circunloquio en la clase de lengua española

Arteaga and Llorente (2009) argue for the importance of addressing lexical regional variety in the Spanish language classroom. They advocate teaching students a dialectally neutral term that will be understood across dialectal zones. One problem with this ap- proach, however, is the difficulty of identifying words that have the most currency among dialects. This paper argues for supplementing the use of neutral terms by the skill of circum- locution, which has been argued to be a valu- able skill for second language learners in general (Rubin, 1975, Oxford and Nyikos, 1989, Schweers, 1999), although it must be taught explicitly. Model exercises that foster the use of circumlocution, while also empha- sizing neutral terms, are given. This combina- tion will allow students to communicate effec- tively with speakers of a wide variety of dia- lects.
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25 Lee mas

A note on the p parabolicity of submanifolds

A note on the p parabolicity of submanifolds

Among the characterizations given by the Kelvin-Nevanlinna-Royden cri- terion for p-parabolicity of a Riemannian manifold, we shall use in this paper those that states that a manifold M is p-parabolic, (with 1 < p < ∞), if and only if it has vanishing p-capacity, namely, there exists a non-empty precompact open set D ⊆ M such that Cap p (D, M) = 0.

19 Lee mas

On the origin and history of the English prepositional type a-hunting: a corpus-based study

On the origin and history of the English prepositional type a-hunting: a corpus-based study

Jespersen shows a combination of the two above-mentioned theories (A Modera English Grammar IV168-69): in a first formulation, he asserted that the progressive tenses "seem to have[r]

13 Lee mas

Analytical modelling of floating zone crystal growth

Analytical modelling of floating zone crystal growth

Analytical results for the floating zone process of silicon crystal growth for three initial lengths of the melt (Ao, kept constant), showing the excess volume, v (relative to that of a[r]

6 Lee mas

Modification of fatty acid composition in broiler chickens fed canola oil

Modification of fatty acid composition in broiler chickens fed canola oil

This article describes the possibility of modifying the composition of fat tissue in broiler chickens fed canola oil, which is high in monounsaturated fatty acids. 128 one-day old broiler chickens, randomly assigned into 4 groups of 32 chicks each, received one of four diets containing 15% oil with diff erent percentages of canola oil (diet 1: 0% canola oil, diet 2: 5% canola oil, diet 3: 10% canola oil and diet 4: 15% canola oil), for 31 days. Each group was divided into 4 subgroups of 8 chicks. The birds were sacrifi ced at day 45 to obtain tissue samples. The fatty acid composition was measured in meat (legs and breasts), fat (abdominal and subcutaneous) and plasma. An increase in oleic acid (p<0.01) was detected, as well as a decrease in linoleic acid (p<0.01), together with a slight increase in α-linolenic acid (p<0.05) with a higher percentage of canola oil. The composition of fat tissue was more representative of the dietary fatty acids than muscle tissue. In conclusion, canola oil increased the content of omega 9 and omega 3 fatty acids and decreased the content of omega 6 fatty acids in meat, fat and plasma in broiler chickens.
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14 Lee mas

Quality improvement of AlInN/p Si heterojunctions with AlN buffer layer deposited by RF sputtering

Quality improvement of AlInN/p Si heterojunctions with AlN buffer layer deposited by RF sputtering

We thank L. Grenet from the CEA-Grenoble (LITEN) and University Grenoble Alpes, France, for the JV characteristics performed under AM1.5G illumination. Partial financial support provided by: the Spanish Government projects: TEC2014-60483-R, TEC2015-71127-C2-2-R; by the Community of Madrid project: S2013/MIT 2790; by the University of Alcalá project: CCG2015/EXP-014; and by the FPI Grant from the University of Alcalá. Support from Junta de Andalucía (Group INNANOMAT, ref. TEP-946) is also acknowledged.

17 Lee mas

Obesidad, enfermedad y longevidad en adultos mexicanos

Obesidad, enfermedad y longevidad en adultos mexicanos

We believe the numbers computed above are under- estimates. First, they ignore the effects of heart disease and cancer, both related to obesity. Second, it is likely that there is at least some underreporting of chronic conditions. This should attenuate all estimates of ef- fects of obesity. Third, throughout we use self-reported conditions either in wave 1 or wave 2 and ignore cause of death (reported by a relative) among those individu- als who die between waves. Thus, if an individual who did not report diabetes in 2003 dies between 2003 and 2012 and a spouse identifies diabetes as the cause of death we do not recode the 2003 self-report. And, finally, the calculations include the protective effects of obesity and overweight, thus dampening the overall impact on mortality. We believe this is incorrect since, at least in the MHAS sample, protective effects are the product of artifacts and misspecified models. However, the results presented above should temper statements suggesting that obesity may have ambiguous or even beneficial ef- fect on survival at older ages. As smoking has done in the past and will continue to do so in the future, obesity has had and will continue to have a strong impact on health status, health care, health costs, and could gradu- ally erode future improvements in longevity.
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9 Lee mas

Art – Two centuries of productivity growth in computing – Nordhaus – 2007

Art – Two centuries of productivity growth in computing – Nordhaus – 2007

Early calculators were “dumb” machines that essentially relied on in- crementation of digits. An important step in the development of modern computers was mechanical representation of logical steps. The first commercially practical information-processing machine was the Jac- quard loom, developed in 1804. This machine used interchangeable punched cards that controlled the weaving and allowed a large variety of patterns to be produced automatically. This invention was part of the inspiration of Charles Babbage, who developed one of the great precur- sor inventions in computation. He designed two major conceptual breakthroughs, the “Difference Engine” and the “Analytical Engine.” The latter sketched the first programmable digital computer. Neither of the Babbage machines was constructed during his lifetime. An attempt in the 1990s by the British Museum to build the simpler Difference En- gine using early-nineteenth-century technologies failed to perform its designed tasks. 5
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32 Lee mas

On the modification of classical orthogonal polynomials: The symmetric case.

On the modification of classical orthogonal polynomials: The symmetric case.

In Section 2 we include all the properties of the Hermite and Gegenbauer polynomials which will need. In Section 3 we study the generalized Hermite polynomials and Section 4 is devoted to the Gegenbauer case. In particular, we obtain their expression in terms of the classical polynomials, the hypergeometric representations, the ratio asymptotics, the second order dierential equation and the three-term recurrerence relation that such generalized polynomials satisfy.

21 Lee mas

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