Asymptotic iteration method for eigenvalue problems

An asymptotic interation method for solving second-order homogeneous linear differential equations of the form y'' = lambda(x) y' + s(x) y is introduced, where lambda(x) \neq 0 and s(x) are C-infinity functions. Applications to Schroedinger type problems, including some with highly singular potentials, are presented.Comment: 14 page

Diet and Lifestyle in Nonalcoholic Fatty Liver Disease

The liver is an essential metabolic organ which governs body energy metabolism connected with adipose tissue and skeletal muscle among other tissues. The prevalence of obesity has reached epidemic proportions in many countries around the world and continues to grow every year which is caused by multiple factors, with diet and lifestyle being the most researched and therefore most important. Nonalcoholic fatty liver disease (NAFLD) is one of the several metabolic complications associated with obesity. The pathology of NAFLD is difficult to recognize or diagnose especially in early stages without a biopsy and therefore can remain undetected for significant time allowing the disease to progress. The diagnosis of NAFLD is crucial to be able to start adequate treatment including changes in diet and lifestyle in the first stage of the disease when the pathology is reversible and prevent the development of severe forms of the disease such as nonalcoholic steatohepatitis (NASH) or the irreversible cirrhosis stage. When the liver becomes damaged, this can lead to some metabolic alterations that have a severe and multifaceted impact in type 2 diabetes mellitus (T2DM), visceral obesity, and cardiovascular disease related to elevated plasmatic cholesterol, triglycerides, transaminases, and others that indicate hepatic disorders and oxidative stress. ..

EPIDEMIOLOGICAL STUDY OF SPANISH RECREATIONAL RUNNERS

The objective of this study was to analyze how different training aspects and biological factors in running affect the probability of suffering an injury and which muscles and joints are more susceptible to develop an injury. A total of 408 subjects, 206 cases and 202 controls, participated in the investigation. The inferior body was more prone to an injury, especially the muscles and tendons associated with the knee and the shank. Several characteristics of the runner and his/her training habits like the sex, age, experience, motivation and mileage have an impact on the injury risk. This information is very useful because biomechanists and coaches can design programs to improve the technique of the runners and reduce the risk of an injury

Challenges of accessibility of a community heritage tourist route: The Route of the Caste War

This article presents the results of an accessibility analysis of The Caste War Route (RGC), prior to its commercialization as a community heritage product. The analysis consists of a diagnosis of the resource to establish destination-planning strategies. The accessibility diagnosis goes beyond adapting physical spaces for transit, considering that the resource is accessible to all types of people, including economic, spatial and temporal accessibility, criteria on which the research focuses. The diagnosis was prepared through a multidisciplinary investigation that collected information from different sectors with qualitative and quantitative tools that combined the recording of data and the opinion of the residents of the area, key informants; Government officials, museum workers, tourism service providers, non-governmental organizations and visitors were included in this research. Accessibility is a multivariate concept; its analysis required an instrument with cultural indicators distributed in categories, which provides objective, rigorous and relevant information. The research approach was qualitative, including Participatory Action Research and ethnographic techniques such as participant observation (PAR), interviews and document review as part of the process. It is necessary to propose promotional strategies focused on rural cultural products, that disseminate the sites and activities considered heritage by the community, and that the inhabitants are willing to share with visitors, so that local hosts are the ones who offer this service. The necessary strategies are the equal participation and involvement of women and men, the participation of students and academics in training courses and orientation to local service providers. These products face important challenges: they must differentiate themselves from others to build a unique local identity, and at the same time, form alliances with other local communities to create and strengthen local tourism products and services to create a complete touristic experience versus isolated experiences in individual communities. Achieving integration is essential for a successful project and the regional growth and development of the localities involved

A basis for variational calculations in d dimensions

In this paper we derive expressions for matrix elements (\phi_i,H\phi_j) for the Hamiltonian H=-\Delta+\sum_q a(q)r^q in d > 1 dimensions. The basis functions in each angular momentum subspace are of the form phi_i(r)=r^{i+1+(t-d)/2}e^{-r^p/2}, i >= 0, p > 0, t > 0. The matrix elements are given in terms of the Gamma function for all d. The significance of the parameters t and p and scale s are discussed. Applications to a variety of potentials are presented, including potentials with singular repulsive terms of the form b/r^a, a,b > 0, perturbed Coulomb potentials -D/r + B r + Ar^2, and potentials with weak repulsive terms, such as -g r^2 + r^4, g > 0.Comment: 22 page

Ultra-compact planoconcave zoned metallic lens based on the fishnet metamaterial

The following article appeared Pacheco-Pena, V., Orazbayev, B., Torres, V., Beruete, M., & Navarro-Cia, M. (n.d). Ultra-compact planoconcave zoned metallic lens based on the fishnet metamaterial. Applied Physics Letters, 103(18), and may be found at http://dx.doi.org/10.1063/1.4827876.A 1.5λ0 -thick planoconcave zoned lens based on the fishnet metamaterial is demonstrated experimentally at millimeter wavelengths. The zoning technique applied allows a volume reduction of 60% compared to a full fishnet metamaterial lens without any deterioration in performance. The structure is designed to exhibit an effective refractive index n = -0.25 at f = 56.7GHz (λ0 = 5.29 mm) with a focal length FL = 47.62 mm = 9λ0. The experimental enhancement achieved is 11.1dB, which is in good agreement with simulation and also with previous full fishnet metamaterial lenses and opens the door for integrated solutions.This work was supported in part by the Spanish Government under contract Consolider Engineering Metamaterials CSD2008-00066 and contract TEC2011- 28664-C02-01. V.P.-P. was sponsored by Spanish Ministerio de Educacion, Cultura y Deporte under Grant No. FPU AP- 2012-3796. B.O. was sponsored by Spanish Ministerio de Economıa y Competitividad under Grant No. FPI BES-2012- 054909. V.T. is sponsored by the Universidad Publica de Navarra. M.B. is sponsored by the Spanish Government via RYC-2011-08221. M.N.-C. was supported by the Imperial College Junior Research Fellowship

Spiked oscillators: exact solution

A procedure to obtain the eigenenergies and eigenfunctions of a quantum spiked oscillator is presented. The originality of the method lies in an adequate use of asymptotic expansions of Wronskians of algebraic solutions of the Schroedinger equation. The procedure is applied to three familiar examples of spiked oscillators