Exact treatment of dispersion relations in pp and p\=p elastic scattering

Based on a study of the properties of the Lerch's transcendent, exact closed forms of dispersion relations for amplitudes and for derivatives of amplitudes in pp and p\=p scattering are introduced. Exact and complete expressions are written for the real parts and for their derivatives at $t=0$ based on given inputs for the energy dependence of the total cross sections and of the slopes of the imaginary parts. The results are prepared for application in the analysis of forward scattering data of the pp and p\=p systems at all energies, where exact and precise representations can be written.Comment: 23 pages, 1 figur

Structure of Forward pp and p\=p Elastic Amplitudes at Low Energies

Exact analytical forms of solutions for Dispersion Relations for Amplitudes and Dispersion Relations for Slopes are applied in the analysis of pp and $\rm {p \bar p}$ scattering data in the forward range at energies below \sqrt(s)\approx 30 \GeV. As inputs for the energy dependence of the imaginary part, use is made of analytic form for the total cross sections and for parameters of the $t$ dependence of the imaginary parts, with exponential and linear factors. A structure for the $t$ dependence of the real amplitude is written, with slopes $B_R$ and a linear factor $\rho-\mu_R t$ that allows compatibility of the data with the predictions from dispersion relations for the derivatives of the real amplitude at the origin. A very precise description is made of all $d\sigma/dt$ data, with regular energy dependence of all quantities. It is shown that a revision of previous calculations of total cross sections, slopes and $\rho$ parameters in the literatures is necessary, and stressed that only determinations based on $d\sigma/dt$ data covering sufficient $t$ range using appropriate forms of amplitudes can be considered as valid.Comment: 28 pages and 26 figure

New properties of the Lerch's transcendent

A new representation of the Lerch''s transcendent F(z, s, a), valid for positive integer s=n=1, 2, … and for z and a belonging to certain regions of the complex plane, is presented. It allows to write an equation relating F(z, n, a) and F(1/z, n, 1-a), which in turn provides an expansion of F(z, n, a) as a power series of 1/z, convergent for |z|>1

El depósito de armas de la azucarera (Alfaro, La Rioja)

En el presente artículo se trata el hallazgo de un depósito de armas: espadas, puñal, casco y umbos de escudo, principalmente, localizados durante la excavación realizada en el año 1969 en la Azucarera de Alfaro (La Rioja). El material es bastante significativo dentro del contexto peninsular. Parece tratarse de un depósito ritual de la guerra sertoriana, de ahí su importancia y el interés de su publicación

A Simplified Elastic Model for Seismic Analysis of Earth-Retaining Structures with Limited Displacements

A simplified elastic model for analyzing static and dynamic interaction between earth-retaining structures and backfill within the range of small displacements is presented. The postulated model covers some of the available models as special cases. The model lends itself readily to the treatment of non-homogeneous backfills with elastic properties varying with depth. Internal (linear) damping in the backfill can be included without impairing the simplicity of the model. Radiation losses due to waves propagating horizontally in fills of semi-infinite extent are inherent to the postulated model. The solutions for some statical and dynamical problems of practical importance show satisfactory agreement with results based on the classical theory of elasticity

Modeling seismic wave propagation and amplification in 1D/2D/3D linear and nonlinear unbounded media

To analyze seismic wave propagation in geological structures, it is possible to consider various numerical approaches: the finite difference method, the spectral element method, the boundary element method, the finite element method, the finite volume method, etc. All these methods have various advantages and drawbacks. The amplification of seismic waves in surface soil layers is mainly due to the velocity contrast between these layers and, possibly, to topographic effects around crests and hills. The influence of the geometry of alluvial basins on the amplification process is also know to be large. Nevertheless, strong heterogeneities and complex geometries are not easy to take into account with all numerical methods. 2D/3D models are needed in many situations and the efficiency/accuracy of the numerical methods in such cases is in question. Furthermore, the radiation conditions at infinity are not easy to handle with finite differences or finite/spectral elements whereas it is explicitely accounted in the Boundary Element Method. Various absorbing layer methods (e.g. F-PML, M-PML) were recently proposed to attenuate the spurious wave reflections especially in some difficult cases such as shallow numerical models or grazing incidences. Finally, strong earthquakes involve nonlinear effects in surficial soil layers. To model strong ground motion, it is thus necessary to consider the nonlinear dynamic behaviour of soils and simultaneously investigate seismic wave propagation in complex 2D/3D geological structures! Recent advances in numerical formulations and constitutive models in such complex situations are presented and discussed in this paper. A crucial issue is the availability of the field/laboratory data to feed and validate such models.Comment: of International Journal Geomechanics (2010) 1-1

Tobacco exposure inhibits SPLUNC1-dependent antimicrobial activity

Background: Tobacco smoke exposure impairs the lung´s innate immune response, leading to an increased risk of chronic infections. SPLUNC1 is a secreted, multifunctional innate defense protein that has antimicrobial activity against Gram negative organisms. We hypothesize that tobacco smoke-induced SPLUNC1 dysfunction contributes to the observed defect in innate immunity in tobacco smokers and that this dysfunction can be used as a potential biomarker of harm. Methods: We collected sputum from never-smokers and otherwise healthy smokers. We performed Western blotting to determine SPLUNC1 levels and determined antimicrobial activity against nontypeable Haemophilus influenzae. An in vitro exposure model was utilized to measure the effect of tobacco exposure on human bronchial epithelial culture (HBEC) antimicrobial activity against H. influenzae. The direct effects of cigarette and little cigar smoke exposure on SPLUNC1 function was determined using 24 h growth measurements and LPS binding assays. Results: H. influenzae growth in cigarette smoker´s sputum was significantly greater compared to never-smokers sputum over 24 h. HBEC supernatants and lysates contained significantly higher numbers of H. influenzae following chronic cigarette and little cigar smoke exposure compared to air-exposed controls. Furthermore, SPLUNC1´s antimicrobial activity and LPS-binding capability against both H. influenzae and P. aeruginosa was attenuated following cigarette and little cigar exposure. Conclusions: These data suggest that cigarette and little cigar exposure impairs SPLUNC1´s antimicrobial ability and that this inhibition may serve as a novel biomarker of harm that can be used to assess the toxicity of commercial tobacco products.Fil: Moore, Patrick J.. University of North Carolina; Estados UnidosFil: Sesma, Juliana. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario; Argentina. Universidad Nacional de Rosario. Facultad de Ciencias Médicas; ArgentinaFil: Alexis, Neil E.. University of North Carolina; Estados UnidosFil: Tarran, Robert. University of North Carolina; Estados Unido

Employing Polyethnography to Navigate Researcher Positionality on Weight Bias

Researchers often focus on the content of their research interests but, depending on the research approach, may pay less attention to the process of locating themselves in relation to the research topic. This paper outlines the dialogue between an interdisciplinary team of researchers who were at the initial stages of forming a research agenda related to weight bias and social justice. Using a polyethnographic approach to guide our discussion, we sought to explore the diverse and common life experiences that influenced our professional interests for pursuing research on weight bias. As a dialogic method, polyethnography is ideally suited for the reflexive work required of researchers seeking to address issues of equity and social justice. Beyond more traditional approaches such as journaling, personal interviews, or researcher notes, the intersubjectivity highlighted by this method affords a richer space for exploration, challenging ideas, taking risks, and collectively interrogating both self and society. Following a discussion of positionality, the dialogue between researchers is presented, followed by their critique of the discussion, informed by professional literature