Three-point functions in superstring theory on AdS 3×S 3×T 4

We consider R and NS spectral flow sectors of type IIB superstring theory on AdS 3 × S 3 × T 4 in the context of the AdS 3/CFT 2 correspondence. We present a derivation of the vertex operators creating spectral flow images of chiral primary states previously proposed in the literature. We compute spectral flow conserving three-point functions involving these operators on the sphere. Using the bulk-to-boundary dictionary, we compare the results with the corresponding correlators in the dual conformal field theory, the symmetric product orbifold of T 4. In the limit of small string coupling, agreement is found in all the cases considered. © SISSA 2009.Fil:Cardona, C.A. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina.Fil:Núñez, C.A. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina

Abordaje transvasto mínimamente invasivo versus abordaje parapatelar medial convencional en la artroplastia total de rodilla en pacientes con gonartrosis: estudio prospectivo comparativo no randomizado

Objetivos: valorar y comparar los resultados a corto plazo de la artroplastia total de rodilla realizada mediante dos vías de abordaje. Material y métodos: estudio prospectivo comparativo que compara abordaje parapatelar medial (24 pacientes) y transvasto mínimamente invasivo (25 pacientes) en artroplastia total de rodilla. Se incluyeron pacientes con gonartrosis grado IV de la clasificación de Kellgren-Lawrence y se excluyeron aquellos menores de 50 años, deformidad en varo (> 15º) o valgo (> 10º), artrosis postraumática, artritis reumatoide, cirugías de revisión, osteotomías correctoras previas, IMC > 40 kg/m2, infección activa local o sistémica y/o deterioro mental. Resultados: se encontraron diferencias estadísticamente significativas en dolor del primer y segundo día postoperatorios a favor del abordaje mínimamente invasivo (1º día: 3,8 ± 2,5 vs. 6,7 ± 2,1; p< 0,001. 2º día: 3 ± 2,1 vs. 6 ± 2; p< 0,001). Conclusiones: no existen diferencias relevantes entre ambos abordajes, por lo que se recomienda la utilización del abordaje con el que el cirujano se encuentre más cómodo y familiarizadoAim: Assess and compare short-term outcomes of total knee arthroplasty performed using two surgical approaches. Material and methods: a prospective study with 49 patients comparing medial parapatellar approach (24 patients) and minimally invasive trans-vastus access (25 patients) in total knee replacement. The patients included suffered knee osteoarthritis grade IV the Kellgren-Lawrence’s classification. Exclusion criteria were age under 50 years, large axial deformity (varus deformity > 15° or valgus > 10°), posttraumatic osteoarthritis, rheumatoid arthritis, revision surgeries, previous osteotomies, BMI> 40 kg/m2 and of course local or systemic active infection and mental impairment. Results: statistically significant differences were found for pain in first and second postoperative days for the minimally invasive approach (1st day: 3.8 ± 2.5 vs. 6.7 ± 2.1; p <0.001. 2nd day: 3 ± 2.1 vs. 6 ± 2; p <0.001). Conclusions: there are not significant differences between mini and standard approaches in knee replacement, so decision about which access to use in knee reconstruction surgery depends on surgeon’s preferences

Thermodynamics of non-local materials: extra fluxes and internal powers

The most usual formulation of the Laws of Thermodynamics turns out to be suitable for local or simple materials, while for non-local systems there are two different ways: either modify this usual formulation by introducing suitable extra fluxes or express the Laws of Thermodynamics in terms of internal powers directly, as we propose in this paper. The first choice is subject to the criticism that the vector fluxes must be introduced a posteriori in order to obtain the compatibility with the Laws of Thermodynamics. On the contrary, the formulation in terms of internal powers is more general, because it is a priori defined on the basis of the constitutive equations. Besides it allows to highlight, without ambiguity, the contribution of the internal powers in the variation of the thermodynamic potentials. Finally, in this paper, we consider some examples of non-local materials and derive the proper expressions of their internal powers from the power balance laws.Comment: 16 pages, in press on Continuum Mechanics and Thermodynamic

On the Construction of Pareto-Compliant Combined Indicators

The most relevant property that a quality indicator (QI) is expected to have is Pareto compliance, which means that every time an approximation set strictly dominates another in a Pareto sense, the indicator must reflect this. The hypervolume indicator and its variants are the only unary QIs known to be Pareto-compliant but there are many commonly used weakly Pareto-compliant indicators such as R2, IGD+,andɛ+. Currently, an open research area is related to finding new Pareto-compliant indicators whose preferences are different from those of the hypervolume indicator. In this article, we propose a theoretical basis to combine existing weakly Pareto-compliant indicators with at least one being Pareto-compliant, such that the resulting combined indicator is Pareto-compliant as well. Most importantly, we show that the combination of Paretocompliant QIs with weakly Pareto-compliant indicators leads to indicators that inherit properties of the weakly compliant indicators in terms of optimal point distributions. The consequences of these new combined indicators are threefold: (1) to increase the variety of available Pareto-compliant QIs by correcting weakly Pareto-compliant indicators, (2) to introduce a general framework for the combination of QIs, and (3) to generate new selection mechanisms for multiobjective evolutionary algorithms where it is possible to achieve/adjust desired distributions on the Pareto front

On the Effect of the Cooperation of Indicator-Based Multiobjective Evolutionary Algorithms

For almost 20 years, quality indicators (QIs) have promoted the design of new selection mechanisms of multiobjective evolutionary algorithms (MOEAs). Each indicator-based MOEA (IB-MOEA) has specific search preferences related to its baseline QI, producing Pareto front approximations with different properties. In consequence, an IB-MOEA based on a single QI has a limited scope of multiobjective optimization problems (MOPs) in which it is expected to have a good performance. This issue is emphasized when the associated Pareto front geometries are highly irregular. In order to overcome these issues, we propose here an island-based multiindicator algorithm (IMIA) that takes advantage of the search biases of multiple IB-MOEAs through a cooperative scheme. Our experimental results show that the cooperation of multiple IB-MOEAs allows IMIA to perform more robustly (considering several QIs) than the panmictic versions of its baseline IB-MOEAs as well as several state-of-the-art MOEAs. Additionally, IMIA shows a Pareto-front-shape invariance property, which makes it a remarkable optimizer when tackling MOPs with complex Pareto front geometries

On the utilization of pair-potential energy functions in multi-objective optimization

In evolutionary multi-objective optimization (EMO), the pair-potential energy functions (PPFs) have been used to construct diversity-preserving mechanisms to improve Pareto front approximations. Despite PPFs have shown promising results when dealing with different Pareto front geometries, there are still some open research questions to improve the way we employ them. In this paper, we answer three important questions: (1) what is the effect of a crucial parameter of some PPFs?, (2) how do we set the optimal parameter value?, and (3) what is the best PPF in EMO? To solve these questions, we designed a brand-new fast algorithm to generate an approximate solution to a PPF-based subset selection problem and, then, we conducted a comprehensive parametrical study to predict the optimal parameter values using a deep neural network. To show the effectiveness of the PPF-based diversity-preserving mechanisms, we selected two application cases: the generation of reference point sets of benchmark problems (DTLZ, WFG, IDTLZ, IWFG, IMOP, and Viennet) with different Pareto front shapes, and the definition of a PPF-based archive that can be coupled to any multi-objective evolutionary algorithm to construct well-diversified Pareto front approximations. Using several diversity indicators, it is shown that the utilization of PPF-based mechanisms lead to good Pareto front approximations regardless of the Pareto front shape

Parallel Multi-Objective Evolutionary Algorithms: A Comprehensive Survey

Multi-Objective Evolutionary Algorithms (MOEAs) are powerful search techniques that have been extensively used to solve difficult problems in a wide variety of disciplines. However, they can be very demanding in terms of computational resources. Parallel implementations of MOEAs (pMOEAs) provide considerable gains regarding performance and scalability and, therefore, their relevance in tackling computationally expensive applications. This paper presents a survey of pMOEAs, describing a refined taxonomy, an up-to-date review of methods and the key contributions to the field. Furthermore, some of the open questions that require further research are also briefly discussed

ARIA 2016: Care pathways implementing emerging technologies for predictive medicine in rhinitis and asthma across the life cycle

The Allergic Rhinitis and its Impact on Asthma (ARIA) initiative commenced during a World Health Organization workshop in 1999. The initial goals were (1) to propose a new allergic rhinitis classification, (2) to promote the concept of multi-morbidity in asthma a

Bases para establecer un programa de manejo integrado de plagas de habichuela en la provincia de Sumapaz (Colombia).

Habichuel

Propiedades magnetocalóricas y estructurales de la manganita de lantano dopada con calcio (La1-xCaxMnO3, 0 ≤x≤0.4)

Las manganitas tipo ABO3, particularmente las dopadas con metales alcalinotérreos (Ca2+), La1-xCaxMnO3, son materiales de gran interés por sus extraordinarias propiedades tecnológicas, particularmente por su posible aplicación en refrigeración magnética. El objetivo de este trabajo fue analizar el comportamiento magnetocalórico de compuestos tipo La1-xCaxMnO3, los cuales se sintetizaron mediante molienda de alta energía durante 5 h, asistida con tratamiento térmico hasta 1100 °C. Mediante DRX se corroboró la síntesis de manganitas perovskita con estructura cristalina tipo ortorrómbica, con distintas concentraciones de dopante. La magnetometría de muestra vibrante demostró el orden paramagnético a temperatura ambiente, se obtuvieron las temperaturas de Curie (Tc) entre 143 K a 243 K, siendo la manganita La0.7Ca0.3MnO3 la de mayor interés. Asimismo, se obtuvieron las isotermas magnéticas alrededor de la Tc, para la composición (x=0.3). Su análisis permitió analizar el efecto magnetocalórico, a través de la determinación del cambio de entropía magnética (-ΔS), la cual varió entre 3 a 7.43 Jkg-1K-1, y la capacidad de refrigeración (RC), la cual se obtuvo en el rango de 24.18 a 93.29 J kg-1. El incremento en el nivel de dopaje (x), produce un aumento en la temperatura de Curie, y en el cambio de entropía magnética, determinado que la composición (x=0.3) es la que mejores propiedades presenta.&nbsp