Not All Antibodies Are Created Equal: Factors That Influence Antibody Mediated Rejection.

Consistent with Dr. Paul Terasaki's "humoral theory of rejection" numerous studies have shown that HLA antibodies can cause acute and chronic antibody mediated rejection (AMR) and decreased graft survival. New evidence also supports a role for antibodies to non-HLA antigens in AMR and allograft injury. Despite the remarkable efforts by leaders in the field who pioneered single antigen bead technology for detection of donor specific antibodies, a considerable amount of work is still needed to better define the antibody attributes that are associated with AMR pathology. This review highlights what is currently known about the clinical context of pre and posttransplant antibodies, antibody characteristics that influence AMR, and the paths after donor specific antibody production (no rejection, subclinical rejection, and clinical dysfunction with AMR)

Spin precession and spin Hall effect in monolayer graphene/Pt nanostructures

Spin Hall effects have surged as promising phenomena for spin logics operations without ferromagnets. However, the magnitude of the detected electric signals at room temperature in metallic systems has been so far underwhelming. Here, we demonstrate a two-order of magnitude enhancement of the signal in monolayer graphene/Pt devices when compared to their fully metallic counterparts. The enhancement stems in part from efficient spin injection and the large resistivity of graphene but we also observe 100% spin absorption in Pt and find an unusually large effective spin Hall angle of up to 0.15. The large spin-to-charge conversion allows us to characterise spin precession in graphene under the presence of a magnetic field. Furthermore, by developing an analytical model based on the 1D diffusive spin-transport, we demonstrate that the effective spin-relaxation time in graphene can be accurately determined using the (inverse) spin Hall effect as a means of detection. This is a necessary step to gather full understanding of the consequences of spin absorption in spin Hall devices, which is known to suppress effective spin lifetimes in both metallic and graphene systems.Comment: 14 pages, 6 figures. Accepted in 2D Materials. https://doi.org/10.1088/2053-1583/aa882

Forming Disk Galaxies in Lambda CDM Simulations

We used fully cosmological, high resolution N-body + SPH simulations to follow the formation of disk galaxies with rotational velocities between 135 and 270 km/sec in a Lambda CDM universe. The simulations include gas cooling, star formation, the effects of a uniform UV background and a physically motivated description of feedback from supernovae. The host dark matter halos have a spin and last major merger redshift typical of galaxy sized halos as measured in recent large scale N--Body simulations. The simulated galaxies form rotationally supported disks with realistic exponential scale lengths and fall on both the I-band and baryonic Tully Fisher relations. An extended stellar disk forms inside the Milky Way sized halo immediately after the last major merger. The combination of UV background and SN feedback drastically reduces the number of visible satellites orbiting inside a Milky Way sized halo, bringing it in fair agreement with observations. Our simulations predict that the average age of a primary galaxy's stellar population decreases with mass, because feedback delays star formation in less massive galaxies. Galaxies have stellar masses and current star formation rates as a function of total mass that are in good agreement with observational data. We discuss how both high mass and force resolution and a realistic description of star formation and feedback are important ingredients to match the observed properties of galaxies.Comment: Revised version after the referee's comments. Conclusions unchanged. 2 new plots. MNRAS in press. 20 plots. 21 page

Filosofía de la responsabilidad social empresarial

Abstract. The company has prioritized like objective the satisfaction of the owner, by means of the maximization of the present value of the company and the exclusive obtaining of utilities; approach that has left to the margin the other groups that have interest in the company, calls stakeholders: workers, clients, suppliers, community, government, citizenship and environment. The presentsocial problems and the deterioration of the environment, demonstrate the failure of the traditional enterprise model, reason why it sets out to change of approach: an enterprise philosophy of social responsibility that considers the interests of all the participants in the enterprise system, with the identification and practice of basic values and other complementary ones, compatibles with social aims, that are included in the enterprise strategy and its daily actions. This new model of management based on values could be made specific by means of a social pact laid out by the companies, constituting itself in roll of the employers one that would contribute to the solution of many problems of the society.Key words: Aims, company, enterprise social responsibility, philosophy, stakeholders, strategy, valuesResumen. La empresa ha priorizado como objetivo la satisfacción del dueño, mediante la maximización del valor actual de la empresa y la exclusiva obtención de utilidades; paradigma que ha dejado al margen los demás grupos que tienen interés en la empresa, llamados stakeholders: trabajadores, clientes, proveedores, comunidad, gobierno, ciudadanía y medio ambiente. Los problemas sociales actuales y el deterioro del medio ambiente, evidencian elfracaso del modelo tradicional, por lo que se propone cambiar de enfoque: una filosofía empresarial de responsabilidad social que tenga en cuenta los intereses de todos los participantes en el sistema empresarial, con la identificación y práctica de unos valores básicos y otros complementarios, congruentes con unos fines sociales, que se incluyan en la estrategia y en sus acciones cotidianas. Este nuevo modelo de gestión basado en valores se podría concretar mediante un pacto social jalonado por las empresas, constituyéndose en el rol del empresariado que contribuiría a la solución de muchos problemas de la sociedad.Palabras Claves. Accionistas, empresa, estrategia, filosofía, metas, responsabilidad social empresarial, valore

Filosofía de la responsabilidad social empresarial = (The Philosophy of enterprise social responsability)

Resumen. La empresa ha priorizado como objetivo la satisfacción del dueño, mediante la maximización del valor actual de la empresa y la exclusiva obtención de utilidades; paradigma que ha dejado al margen los demás grupos que tienen interés en la empresa, llamados stakeholders: trabajadores, clientes, proveedores, comunidad, gobierno, ciudadanía y medio ambiente. Los problemas sociales actuales y el deterioro del medio ambiente, evidencian el fracaso del modelo tradicional, por lo que se propone cambiar de enfoque: una filosofía empresarial de responsabilidad social que tenga en cuenta los intereses de todos los participantes en el sistema empresarial, con la identificación y práctica de unos valores básicos y otros complementarios, congruentes con unos fines sociales, que se incluyan en la estrategia y en sus acciones cotidianas. Este nuevo modelo de gestión basado en valores se podría concretar mediante un pacto social jalonado por las empresas, constituyéndose en el rol del empresariado que contribuiría a la solución de muchos problemas de la sociedad. Abstract. The company has prioritized like objective the satisfaction of the owner, by means of the maximization of the present value of the company and the exclusive obtaining of utilities; approach that has left to the margin the other groups that have interest in the company, calls stakeholders: workers, clients, suppliers, community, government, citizenship and environment. The present social problems and the deterioration of the environment, demonstrate the failure of the traditional enterprise model, reason why it sets out to change of approach: an enterprise philosophy of social responsibility that considers the interests of all the participants in the enterprise system, with the identification and practice of basic values and other complementary ones, compatibles with social aims, that are included in the enterprise strategy and its daily actions. This new model of management based on values could be made specific by means of a social pact laid out by the companies, constituting itself in roll of the employers one that would contribute to the solution of many problems of the society

On the Structure of Dark Matter Halos at the Damping Scale of the Power Spectrum with and without Relict Velocities

We report a series of high-resolution cosmological N-body simulations designed to explore the formation and properties of dark matter halos with masses close to the damping scale of the primordial power spectrum of density fluctuations. We further investigate the effect that the addition of a random component, v_rms, into the particle velocity field has on the structure of halos. We adopted as a fiducial model the Lambda Warm Dark Matter cosmology with a non-thermal sterile neutrino mass of 0.5 keV. The filtering mass corresponds then to M_f = 2.6x10^12 M_sun/h. Halos of masses close to M_f were simulated with several million of particles. The results show that, on one hand, the inner density slope of these halos (at radii <~0.02 the virial radius Rvir) is systematically steeper than the one corresponding to the NFW fit or to the CDM counterpart. On the other hand, the overall density profile (radii larger than 0.02Rvir) is less curved and less concentrated than the NFW fit, with an outer slope shallower than -3. For simulations with v_rms, the inner halo density profiles flatten significantly at radii smaller than 2-3 kpc/h (<~0.010-0.015Rvir). A constant density core is not detected in our simulations, with the exception of one halo for which the flat core radius is ~1 kpc/h. Nevertheless, if ``cored'' density profiles are used to fit the halo profiles, the inferred core radii are ~0.1-0.8 kpc/h, in rough agreement with theoretical predictions based on phase-space constrains, and on dynamical models of warm gravitational collapse. A reduction of v_rms by a factor of 3 produces a modest decrease in core radii, less than a factor of 1.5. We discuss the extension of our results into several contexts, for example, to the structure of the cold DM micro-halos at the damping scale of this model.Comment: 13 pages, 6 figures, accepted for publication in The Astrophysical Journa

On the Issue of the \zeta Series Convergence and Loop Corrections in the Generation of Observable Primordial Non-Gaussianity in Slow-Roll Inflation. Part II: the Trispectrum

We calculate the trispectrum T_\zeta of the primordial curvature perturbation \zeta, generated during a {\it slow-roll} inflationary epoch by considering a two-field quadratic model of inflation with {\it canonical} kinetic terms. We consider loop contributions as well as tree level terms, and show that it is possible to attain very high, {\it including observable}, values for the level of non-gaussianity \tau_{NL} if T_\zeta is dominated by the one-loop contribution. Special attention is paid to the claim in JCAP {\bf 0902}, 017 (2009) [arXiv:0812.0807 [astro-ph]] that, in the model studied in this paper and for the specific inflationary trajectory we choose, the quantum fluctuations of the fields overwhelm the classical evolution. We argue that such a claim actually does not apply to our model, although more research is needed in order to understand the role of quantum diffusion. We also consider the probability that an observer in an ensemble of realizations of the density field sees a non-gaussian distribution. In that respect, we show that the probability associated to the chosen inflationary trajectory is non-negligible. Finally, the levels of non-gaussianity f_{NL} and \tau_{NL} in the bispectrum B_\zeta and trispectrum T_\zeta of \zeta, respectively, are also studied for the case in which \zeta is not generated during inflation.Comment: LaTex File, 27 pages, 8 figures. v2: Previous Section 2 has been removed. Two new sections (3 and 4) discussing the classicality condition given by Byrnes, Choi, and Hall, in JCAP 0902, 017 (2009), and the probability that an observer sees a non-gaussian distribution have been added. v3: Version accepted for publication in Physical Review

Data Portraits and Intermediary Topics: Encouraging Exploration of Politically Diverse Profiles

In micro-blogging platforms, people connect and interact with others. However, due to cognitive biases, they tend to interact with like-minded people and read agreeable information only. Many efforts to make people connect with those who think differently have not worked well. In this paper, we hypothesize, first, that previous approaches have not worked because they have been direct -- they have tried to explicitly connect people with those having opposing views on sensitive issues. Second, that neither recommendation or presentation of information by themselves are enough to encourage behavioral change. We propose a platform that mixes a recommender algorithm and a visualization-based user interface to explore recommendations. It recommends politically diverse profiles in terms of distance of latent topics, and displays those recommendations in a visual representation of each user's personal content. We performed an "in the wild" evaluation of this platform, and found that people explored more recommendations when using a biased algorithm instead of ours. In line with our hypothesis, we also found that the mixture of our recommender algorithm and our user interface, allowed politically interested users to exhibit an unbiased exploration of the recommended profiles. Finally, our results contribute insights in two aspects: first, which individual differences are important when designing platforms aimed at behavioral change; and second, which algorithms and user interfaces should be mixed to help users avoid cognitive mechanisms that lead to biased behavior.Comment: 12 pages, 7 figures. To be presented at ACM Intelligent User Interfaces 201

Efecto de la fertilización a la pradera en la densidad básica de la madera de Pinus radiata. D. Don.

The effects of pasture fertilization on basic density of Pinus radiata wood growing in silvopastoral sistem, for two trials submitted to different fertilization schemes: fertilized pasture and unfertilized pasture, are shown in this study. In addition, the different social classes existing in the dominant, intermediate and suppressed stands, are considered. To determine the basic density of wood, disks extracted at a diameter breast height, where annual rings were separated, measuring for each one of them its green volume and dry weight, were used. Statistical analyses showed that density of wood was effected by pasture fertilization, remaining its effect for a period of two and three years depending on the social class. Pasture fertilization effects are higher in the suppressed trees, lower in the intermediate trees, and without any effect in the dominant trees. As a general conclusion it was determined that pastures fertilization decreases basic density on Pinus radiata, especially during its first 10 years of tree growth. It was also found that on trees growing on pastures, there is no significant variation on basic density of wood during their first 10 years of growth. This behavior is the result of the intensive management of the trees forcing them to compete for light for forage development.El presente estudio muestra las diferencias en la densidad b&aacute;sica de la madera del Pinus radiata, para dos ensayos sometidos a diferentes esquemas de fertilizaci&oacute;n: pradera fertilizada y pradera sin fertilizar. Adem&aacute;s, se consideran las diferentes clases sociales presentes en los rodales: dominantes, intermedios y suprimidos. Para la determinaci&oacute;n de la densidad b&aacute;sica se utilizaron rodelas extra&iacute;das al di&aacute;metro a la altura del pecho, en la cual los anillos de crecimiento fueron separados, determinando para cada uno de ellos su volumen en estado verde y su peso seco al horno. Los an&aacute;lisis estad&iacute;sticos demostraron que la densidad disminuye luego de la fertilizaci&oacute;n, prolong&aacute;ndose el efecto por un per&iacute;odo de dos a tres a&ntilde;os dependiendo de la clase social. Los efectos de la fertilizaci&oacute;n son mayores en los &aacute;rboles suprimidos, menores en los intermedios y sin efecto en los &aacute;rboles dominantes. Como conclusi&oacute;n general se estableci&oacute; que la fertilizaci&oacute;n de la pradera disminuye la densidad b&aacute;sica del Pinus radiata, sobre todo en los primeros 10 a&ntilde;os de crecimiento del &aacute;rbol. As&iacute; tambi&eacute;n se encontr&oacute; que los &aacute;rboles creciendo en praderas durante sus primeros 10 a&ntilde;os de crecimiento no se producen variaciones significativas en la densidad b&aacute;sica de la madera. Este comportamiento es producto del manejo intensivo que se somete los &aacute;rboles, en virtud de buscar una mayor cantidad de luz para el desarrollo del forraje