Malnutrition as cause and consequence of sensory distorsiones

La malnutrición es una enfermedad provocada por un exceso o defecto en el consumo o aprovechamiento de los nutrientes. Habitualmente, se utiliza este término para referirse a la desnutrición, es decir, a un trastorno derivado del déficit de algún macro y o micronutrientes. Las alteraciones quimiosensoriales pueden reducir de forma importante la alimentación en el individuo, por lo que es importante verificar que el aporte de nutrientes y, de forma concreta, de algunos micronutrientes, sea suficiente, ya que alguno de ellos, como el zinc, desempeñan un papel primordial en las alteraciones del gusto y del olfato. Además, el paciente malnutrido o con una alimentación que excluya gran número de alimentos, tiene mayor riesgo de presentar déficits de dichos micronutrientes. Diversas enfermedades, tanto agudas como crónicas, se asocian a alteraciones de la percepción sensorial, y pueden llegar a afectar a más del 50% de las personas mayores de 65 años. Los efectos provocados por los fármacos y algunos tratamientos como la quimioterapia y la radioterapia, juegan también un papel muy importante en la distorsión sensorial y en la incidencia de malnutriciónMalnutrition is a pathological condition caused by an excess or deficiency in the consumption or the use of the nutrients. Usually this term refers to a lack of adequate nourishment, a disorder resulting from a deficiency of some macro and/or micronutrients. Chemo-sensory alterations can significantly reduce food choice and intake, so it is very important to verify that the supply of nutrients and specifically of some micronutrients are sufficient. Some of them, such as “zinc”, play a very important role in alterations in the sense of taste and smell. In addition malnutrition patients or a poorly-balanced diet or faulty utilization of foods have increased the risk of deficiencies in these micronutrients. Several types of diseases, both acute and chronic ones, are associated with sensory perception and can affect more than 50% of people over 65 years old. The effects caused by drugs and some treatments such as chemotherapy and radiation therapy play an important role in sensory distortion and the incidence of malnutritio

A new special class of Petrov type D vacuum space-times in dimension five

Using extensions of the Newman-Penrose and Geroch-Held-Penrose formalisms to five dimensions, we invariantly classify all Petrov type $D$ vacuum solutions for which the Riemann tensor is isotropic in a plane orthogonal to a pair of Weyl alligned null directionsComment: 4 pages, 1 table, no figures. Contribution to the proceedings of the Spanish Relativity Meeting 2010 held in Granada (Spain

Initial data sets for the Schwarzschild spacetime

A characterisation of initial data sets for the Schwarzschild spacetime is provided. This characterisation is obtained by performing a 3+1 decomposition of a certain invariant characterisation of the Schwarzschild spacetime given in terms of concomitants of the Weyl tensor. This procedure renders a set of necessary conditions --which can be written in terms of the electric and magnetic parts of the Weyl tensor and their concomitants-- for an initial data set to be a Schwarzschild initial data set. Our approach also provides a formula for a static Killing initial data set candidate --a KID candidate. Sufficient conditions for an initial data set to be a Schwarzschild initial data set are obtained by supplementing the necessary conditions with the requirement that the initial data set possesses a stationary Killing initial data set of the form given by our KID candidate. Thus, we obtain an algorithmic procedure of checking whether a given initial data set is Schwarzschildean or not.Comment: 16 page

On multi-scale asymptotic structure of eigenfunctions in a boundary value problem with concentrated masses near the boundary

We construct two-term asymptotics ?? k = ?m?2(M + ??k + O(?3/2)) of eigenvalues of a mixed boundary-value problem in ? R2 with many heavy (m > 2) concentrated masses near a straight part of the boundary ? . ? is a small positive parameter related to size and periodicity of the masses; k ? N. The main term M > 0 is common for all eigenvalues but the correction terms ?k , which are eigenvalues of a limit problem with the spectral Steklov boundary conditions on , exhibit the effect of asymptotic splitting in the eigenvalue sequence enabling the detection of asymptotic forms of eigenfunctions. The justification scheme implies isolating and purifying singularities of eigenfunctions and leads to a new spectral problem in weighed spaces with a "strongly" singular weight.This research work has been partially supported by Spanish MINECO, MTM2013-44883-P. Also, the research work of the first author has been partially supported by Russian Foundation of Basic research (project 15–01–02175)

Spinor calculus on 5-dimensional spacetimes

Penrose's spinor calculus of 4-dimensional Lorentzian geometry is extended to the case of 5-dimensional Lorentzian geometry. Such fruitful ideas in Penrose's spinor calculus as the spin covariant derivative, the curvature spinors or the definition of the spin coefficients on a spin frame can be carried over to the spinor calculus in 5-dimensional Lorentzian geometry. The algebraic and differential properties of the curvature spinors are studied in detail and as an application we extend the well-known 4-dimensional Newman-Penrose formalism to a 5-dimensional spacetime.Comment: Convention mismatch and minor typos fixed. To appear in Journal of Mathematical Physic

Adsorption of heavy metals from coal acid mine drainage by shrimp shell waste: Isotherm and continuous-flow studies

The main characteristics of coal acid mine drainage (AMD) are low pH and high concentrations of sulfate and different metallic ions. The objective of this research was to study the sorption equilibrium of the removal of metal ions and acids present in coal AMD using shrimp shell in natura (SS) as a biomaterial as well as the behavior of the continuous-flow removal process. The isotherms assays were carried out with synthetic solutions and natural AMD aiming to identify significant differences on metals ions removal by SS. Five isotherm models were studied. R2 values and error statistical functions studies showed that the Freundlich isotherm model was the most appropriate for fitting the experimental data with both synthetic solutions and natural AMD, indicating a metallic removal via a physisorption mechanism. The removal of metal ions in continuous descendent flow was up to 90% Fe and 88% Mn, and the pH increased from 3.49 to 6.77. The adsorption capacities of Fe and Mn resulted in 17.43 and 3.87 mg g−1 SS, respectively. Computing chemical modelling (Visual MINTEQ® software) indicated the sorption was a predominant mechanism on AMD remediation with SS, but with high pH-dependence. This study confirms the suitability of the proposed treatment and provides valuable information for designing a low-cost remediation process for AM

Aplication of the statistical experimental design to optimize mine-impacted water (MIW) remediation using schrimp-shell

Mine-impacted water (MIW) is one of the most serious mining problems and has a high negative impact on water resources and aquatic life. The main characteristics of MIW are a low pH (between 2 and 4) and high concentrations of SO42− and metal ions (Cd, Cu, Ni, Pb, Zn, Fe, Al, Cr, Mn, Mg, etc.), many of which are toxic to ecosystems and human life. Shrimp shell was selected as a MIW treatment agent because it is a low-cost metal-sorbent biopolymer with a high chitin content and contains calcium carbonate, an acid-neutralizing agent. To determine the best metal-removal conditions, a statistical study using statistical planning was carried out. Thus, the objective of this work was to identify the degree of influence and dependence of the shrimp-shell content for the removal of Fe, Al, Mn, Co, and Ni from MIW. In this study, a central composite rotational experimental design (CCRD) with a quadruplicate at the midpoint (22) was used to evaluate the joint influence of two formulation variables—agitation and the shrimp-shell content. The statistical results showed the significant influence (p < 0.05) of the agitation variable for Fe and Ni removal (linear and quadratic form, respectively) and of the shrimp-shell content variable for Mn (linear form), Al and Co (linear and quadratic form) removal. Analysis of variance (ANOVA) for Al, Co, and Ni removal showed that the model is valid at the 95% confidence interval and that no adjustment needed within the ranges evaluated of agitation (0–251.5 rpm) and shrimp-shell content (1.2–12.8 g L−1). The model required adjustments to the 90% and 75% confidence interval for Fe and Mn removal, respectively. In terms of efficiency in removing pollutants, it was possible to determine the best experimental values of the variables considered as 188 rpm and 9.36 g L−1 of shrimp-shell

On correctors for spectral problems in the homogenization of Robin boundary conditions with very large parameters

We obtain estimates for convergence rates of the eigenelements (λ", u") for the Laplace operator in a domain ⊂ R3 periodically perforated along a plane γ = ∩ {x1 = 0}. The boundary conditions are of the Dirichlet type on ∂ and of the Robin type, involving a large parameter O(ε− ), on the boundary of the cavities. The small parameter ε denotes the period while the size of each cavity is O(ε ). Here we consider the most significant case where α = κ = 2