Detailed theoretical predictions of the outskirts of dark matter halos

In the present work we describe the formalism necessary to derive the properties of dark matter halos beyond two virial radius using the spherical collapse model (without shell crossing), and provide the framework for the theoretical prediction presented in Prada et al. (2005). We show in detail how to obtain within this model the probability distribution for the spherically-averaged enclosed density at any radii P(delta,r). Using this probability distribution, we compute the most probable and mean density profiles, which turns out to differ considerably from each other. We also show how to obtain the typical profile, as well as the probability distribution and mean profile for the spherically averaged radial velocity. Two probability distributions are obtained: a first one is derived using a simple assumption, that is, if Q is the virial radius in Lagrangian coordinates, then the enclosed linear contrast delta_l(q,Q) must satisfy the condition that delta_l(q=Q) = delta_vir, where delta_vir is the linear density contrast within the virial radius Rvir at the moment of virialization. Then we introduce an additional constraint to obtain a more accurate P(delta,r) which reproduces to a higher degree of precision the distribution of the spherically averaged enclosed density found in the simulations. This new constraint is delta_l(q,Q) < delta_vir for all q > Q, which means that there are no radii larger than Rvir where the density contrast is larger than that used to define the virial radius. Finally, we compare in detail our theoretical predictions for the probability distributions with the results found in the simulations.Comment: 12 pages, 8 figures, 1 table, replaced to match the published versio

Aspectos relevantes para el diseño de planes de salud sostenibles orientados a los grupos de interés. Una propuesta basada en la Guía ISO 26000: 2010

Fundamentos : Los planes de salud de las comunidades autónomas pue- den incorporar criterios de desarrollo sostenible en su elaboración. No se han realizado análisis al respecto o propuestas de elaboración e indicadores. El objetivo fue la elaboración de un panel de indicadores de seguimiento orientados al desarrollo sostenible que contribuyan a gestionar los impactos económicos, sociales y medioambientales de los sistemas sanitarios. Método: Se utilizó una variación del método RAND/UCLA o técnica de Delphi modificada. El proceso consistió en un análisis bibliográfico y de contexto de las materias y asuntos relacionados con sanidad y responsabi- lidad social tomando como base ISO 26000:2010. Se realizó una encuesta mediante muestreo intencional a una selección de 70 miembros expertos de los grupos de interés identificados y un grupo de discusión para determinar el consenso sobre los asuntos tratados en la encuesta. La investigación fue realizada en 2015. Resultados: De la revisión bibliográfica se obtuvieron 33 asuntos rela - cionados con sanidad incluidos en ISO 26000:2010. De la encuesta, 7 resul- taron relevantes con alto consenso, 8 de relevancia y consenso medio y 18 con menor relevancia y alto nivel de disenso. El grupo de expertos excluyó 4 de los 18 asuntos con menor consenso. Conclusiones: 29 de los 33 asuntos incluidos en el trabajo, repartidos en las 7 materias fundamentales contenidas en la guía ISO 26000 de res- ponsabilidad social, resultaron relevantes para los grupos de interés en re- lación con su posible inclusión en los planes de salud. Se elaboró un panel de indicadoresBackground: Health plans of the Spanish autonomous communities can incorporate sustainable development criteria in its development. There have been no analysis or proposals about development and indicators. The goal is to add a contribution to help build better health plans aimed at sustainable de- velopment and help to manage economic, social and environmental impacts of health systems criteria. Methods: We used a variation of the RAND/UCLA or modified Delphi technique method. The process consisted of a bibliographical and context matters and issues related to health and social responsibility analysis based on ISO 26000: 2010. A survey by deliberately to a selection of 70 expert members of the identified stakeholders was carried out and a discussion group was held to determine the consensus on the issues addressed in the survey sample. The research was conducted in 2015. Results: From the literature review 33 health issues included in ISO 26000:2010 were obtained. 7 survey proved relevant high consensus, 8 re- levance and average consensus and 18 with less relevance and high level of dissent. The expert group excluded 4 of the 18 subjects with less consensus. Conclusions: 29 issues included 33 at work, divided into 7 subjects contained in the guide ISO 26000 of social responsibility, were relevant stakeholders regarding possible inclusion in health plans. Considering the direct relationship published by ISO (International Organization for Stan- dardization) among the issues ISO 26000 and the economic, social and envi- ronmental indicators in GRI (Global Reporting Initiative) in its G4 version, a panel with monitoring indicators related to relevant issues were elaborated.Los autores agradecen el apoyo recibido por la Universidad Jaume I (proyecto P1.1B2013-48) y el Máster en Sostenibilidad y Responsabilidad Social Corporativa (UJI-UNED)

Chloroplast fructose-1,6-bisphosphatase: Modification of non-covalent interactions promote the activation by chimeric Escherichia coli thioredoxins

AbstractAlthough all thioredoxins contain a highly conserved amino acid sequence responsible for thiol/disulfide exchanges, only chloroplast thioredoxin-f is effective in the reductive stimulation of chloroplast fructose- 1,6-bisphosphatase. We set out to determine whether Escherichia coli thioredoxin becomes functional when selected modulators alter the conformation of the target enzyme. Wild type and chimeric Escherichia coli thioredoxins match the chloroplast counterpart when the activation of chloroplast fructose- 1,6-bssphosphatase is performed in the presence of fructose 1,6-bisphosphate, Ca2+, and either trichloroacetate or 2-propanol. These modulators of enzyme activity do change the conformation of chloroplast fructose-1,6-bisphosphatase whereas bacterial thioredoxins remain unaltered. Given that fructose 1,6-bisphosphate, Ca2+, and non-physiological perturbants modify non-covalent interactions of the protein but do not participate in redox reactions, these results strongly suggest that the conformation of the target enzyme regulates the rate of thiol/disulfide exchanges catalyzed by protein disulfide oxidoreductases

How far do they go? The outer structure of dark matter halos

We study the density profiles of collapsed galaxy-size dark matter halos with masses 1e11-5e12 Msun focusing mostly on the halo outer regions from the formal virial radius Rvir up to 5-7Rvir. We find that isolated halos in this mass range extend well beyond Rvir exhibiting all properties of virialized objects up to 2-3Rvir: relatively smooth density profiles and no systematic infall velocities. The dark matter halos in this mass range do not grow as one naively may expect through a steady accretion of satellites, i.e., on average there is no mass infall. This is strikingly different from more massive halos, which have large infall velocities outside of the virial radius. We provide accurate fit for the density profile of these galaxy-size halos. For a wide range (0.01-2)Rvir of radii the halo density profiles are fit with the approximation rho=rho_s exp(-2n[x^{1/n}-1])+rho_m, where x=r/r_s, rho_m is the mean matter density of the Universe, and the index n is in the range n=6-7.5. These profiles do not show a sudden change of behavior beyond the virial radius. For larger radii we combine the statistics of the initial fluctuations with the spherical collapse model to obtain predictions for the mean and most probable density profiles for halos of several masses. The model give excellent results beyond 2-3 formal virial radii.Comment: 15 pages, 10 figures, submitted to Ap

Microfluidic jet impacts on deep pools: transition from capillary-dominated cavity closure to gas-pressure-dominated closure at higher Weber numbers

Studying liquid jet impacts on a liquid pool is crucial for various engineering and environmental applications. During jet impact, the free surface of the pool deforms and a cavity is generated. Simultaneously, the free surface of the cavity extends radially outward and forms a rim. Eventually the cavity collapses by means of gas inertia and surface tension. Our numerical investigation using an axisymmetric model in Basilisk C explores cavity collapse dynamics under different impact velocities and gas densities. We validate our model against theory and experiments across a previously unexplored parameter range. Our results show two distinct regimes in the cavity collapse mechanism. By considering forces pulling along the interface, we derive scaling arguments for the time of closure and maximum radius of the cavity, based on the Weber number. For jets with uniform constant velocity from tip to tail and, the cavity closure is capillary-dominated and happens below the surface (deep seal). In contrast, for the cavity closure happens above the surface (surface seal) and is dominated by the gas entrainment and the pressure gradient that it causes. Additionally, we monitor gas velocity and pressure throughout the impact process. This analysis reveals three critical moments of maximum gas velocity: before impact, at the instant of cavity collapse and during droplet ejection following cavity collapse. Our results provide information for understanding pollutant transport during droplet impacts on large bodies of water, and other engineering applications, like additive manufacturing, lithography and needle-free injections.</p