The density-magnetic field relation in the atomic ISM

We present numerical experiments aimed to study the correlation between the magnetic field strength, B, and the density, n, in the cold atomic interstellar medium (CNM). We analyse 24 magnetohydrodynamic models with different initial magnetic field intensities (B 0 = 0.4, 2.1, 4.2, and 8.3 μG) and/or mean densities (2, 3, and 4 cm -3 ), in the presence of driven and decaying turbulence, with and without self-gravity, in a cubic computational domain with 100 pc by side. Our main findings are as follows: (i) For forced simulations that reproduce the main observed physical conditions of the CNM in the solar neighbourhood, a positive correlation between B and n develops for all the B 0 values. (ii) The density at which this correlation becomes significant (≲30 cm -3 ) depends onB 0 but is not sensitive to the presence of self-gravity. (iii) The effect of self-gravity, when noticeable, consists of producing a shallower correlation at high densities, suggesting that, in the studied regime, self-gravity induces motions along the field lines. (iv) Self-gravitating decaying modelswhere theCNMis subsonic and sub- Alfvénic with β ≲ 1 develop a high-density positive correlation whose slopes are consistent with a constant β(n). (v) Decaying models where the low-density CNM is subsonic and sub- Alfvénic with β > 1 show a negative correlation at intermediate densities, followed by a high-density positive correlation.Fil: Gazol, A.. Universidad Nacional Autónoma de México; MéxicoFil: Villagran Azuara, Marco Adrian. Universidad Nacional Autónoma de México; México. Consejo Nacional de Investigaciónes Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Astronomía y Física del Espacio. - Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Astronomía y Física del Espacio; Argentin

Soliton structures in a molecular chain model with saturation

In the present work, we study, by means of a one-dimensional lattice model, the collective excitations corresponding to intra molecular ones of a chain like proteins. It is shown that such excitations are described by the Nonlinear Schrodinger equation with saturation. The solutions obtained here are the bell solitons, bubbles, kinks and crowdons. Since they belong to different sectors on the parametric space, the bubble condensation could give place to some important changes of face in this kind of nonlinear system. Additionally, it is shown that the limiting velocity of the solitons is the velocity of sound waves corresponding to longitudinal vibrations of molecules.Comment: 12 pages, 4 figure

In Search of the Ethical Empire: Medieval Chinese Debates on Fengjian and Junxian.

What moral principles and organizational models were used to discuss imperial rule in China? What historical precedents were invoked to shape the institutions and practices of governance? In which ways, if any, was the administrative division of the realm conceived to be the foundation for promoting the well-being of the population and the stability of the ruling dynasty? In responding to these questions, political thinkers of the medieval period articulated their views around two models of virtuous rule; the decentralized system of investiture of hereditary lords (fengjian) often associated with the Zhou dynasty (1045–256 BCE), and the centralized administrative system (junxian) first established by the Qin dynasty (221–209 BCE) and consolidated during the Han dynasty (206 BCE–220 CE). In this dissertation, I explore the medieval Chinese debates between supporters of decentralized, yet cooperative, sovereignty along the lines of the fengjian model, and those who advocated the junxian system’s centralized administrative model.PhDAsian Languages and CulturesUniversity of Michigan, Horace H. Rackham School of Graduate Studieshttp://deepblue.lib.umich.edu/bitstream/2027.42/113389/1/igvilla_1.pd

Effect of supplementary cementitious materials on capillary sorption : relation with drying rate and testing time

The water sorption phenomenon in a cementitious matrix is responsible for the ingress of several deleterious agents, and it is directly related to pore connectivity and pore volume. One of the most common tests used to describe this mechanism is the capillary sorption test. Furthermore, the drying rate (DR) is a process that strongly depends on the transport properties and also provides valuable information related to porosity and durability. Supplementary cementitious materials (SCMs) are known to enhance durability-related properties, especially pore refinement with time due to the pozzolanic action. Therefore, changes in the pore structure could be assessed by means of the capillary sorption and drying rate. For this study, mortars with ground granulated blast-furnace slag, natural pozzolan and limestone powder at three different levels of replacement were made and the capillary sorption test was performed at 28 and 90 days. Weight loss was also assessed at 28 days and the DR was calculated. Calculation of the weight gain, weight loss, DR and capillary sorption rate (CSR) is made considering the stoppage of the test at different stages. A comparison between different approaches in the calculations is made. Also, the relation of DR and CSR is assessed. Results show the effect of SCMs with time, and also the influence of the calculations on the CSR and DR values

Computational Methods for Parameter Estimation in Climate Models

Intensive computational methods have been used by Earth scientists in a wide range of problems in data inversion and uncertainty quantification such as earthquake epicenter location and climate projections. To quantify the uncertainties resulting from a range of plausible model configurations it is necessary to estimate a multidimensional probability distribution. The computational cost of estimating these distributions for geoscience applications is impractical using traditional methods such as Metropolis/Gibbs algorithms as simulation costs limit the number of experiments that can be obtained reasonably. Several alternate sampling strategies have been proposed that could improve on the sampling efficiency including Multiple Very Fast Simulated Annealing (MVFSA) and Adaptive Metropolis algorithms. The performance of these proposed sampling strategies are evaluated with a surrogate climate model that is able to approximate the noise and response behavior of a realistic atmospheric general circulation model (AGCM). The surrogate model is fast enough that its evaluation can be embedded in these Monte Carlo algorithms. We show that adaptive methods can be superior to MVFSA to approximate the known posterior distribution with fewer forward evaluations. However the adaptive methods can also be limited by inadequate sample mixing. The Single Component and Delayed Rejection Adaptive Metropolis algorithms were found to resolve these limitations, although challenges remain to approximating multi-modal distributions. The results show that these advanced methods of statistical inference can provide practical solutions to the climate model calibration problem and challenges in quantifying climate projection uncertainties. The computational methods would also be useful to problems outside climate prediction, particularly those where sampling is limited by availability of computational resources.National Science Foundation OCE-0415251CONACyT-Mexico 159764Institute for Geophysic

“The highest wine and under the most beautiful sky”. Patrimonial processes, tourism and business strategies. Cafayate´s case (Calchaquies Valley) in the Northern of Argentine

Este trabajo busca contribuir a la reflexión crítica sobre los procesos de patrimonialización en América Latina a través del estudio de un caso. Circunscripto este a Cafayate, Región de los Valles Calchaquíes, provincia de Salta, Norte de Argentina, donde en la última década se diseñaron e implementaron proyectos de valorización y potenciación del vino, posicionándolo como el principal patrimonio y atractivo local. Intervienen en ello distintos agentes: dependencias del gobierno provincial, el Banco Interamericano de Desarrollo (BID) y cámaras empresariales vitivinícolas. La Ruta del vino y el Museo del vino y de la vid se dirigen en ese sentido, tendiendo a enlazar vino y turismo. Considerando que el patrimonio se construye socialmente, aquí nos ocupamos de dar cuenta del trabajo social implicado en su estimulo, activación y dinamización. Se analizan los sentidos que circulan en torno al patrimonio en específicos ámbitos, considerando su uso y apropiación en el marco de estrategias empresariales del sector vitivinícola. La indagación por el proceso de patrimonialización del vino se detiene sobre las distintas dimensiones de orden político, económico y cultural- que se implican en éste, mapeando las interrelaciones que lo hacen posible. En ese entretejido, no exento de tensiones y conflictos, distintos actores, agentes y grupos en condiciones diferenciales de poder ponen en juego intereses diferentes obteniendo dispares beneficios. Asimismo, las transformaciones inscriptas en la patrimonialización reciente del vino son puestas en perspectiva histórica y en relación con la construcción de Cafayate como un destino turístico, sucedida en los años 70, y la reconversión productiva de los años 90 en adelante. Una parte del trabajo se afirma en la revisión de documentos institucionales, folletería de propaganda turística, periódicos locales y consulta de las páginas de internet, y la otra hace uso de los registros de observación y de la información obtenida mediante entrevistas a funcionarios municipales y agentes privados del sector turismo.This project seeks to contribute a critical reflection about the patrimonial processes in Latin America through an specific case: It refers to Cafayate, which is a city on Calchaquies Valley, in the Provincie of Salta ( Nothern of Argentine ) where in the past decade were designed and implemented projects of "Valuation" and "Potentiality" of wine, positioning it as the main heritage and local attraction. Various actors are involved in it such as provincial government agencies, Inter-American Development Bank (IDB) and wine business chambers. For this reason, the "Wine Route" and the "Museum of Wine and grapevine” are heading in that direction, tending to link wine and tourism. In addition, considering that "heritage" is constructed socially, we are busy with giving account about the social work involved in its stimulus, activation and energizing. It discusses the ways that circulate the heritage in a specific field, considering its use and ownership within the wine sector business strategies. Furthermore, The inquiry by the wine patrimonialization process stops on the various dimensions-political, economic and cultural-that are involved in this, and research the relationships that make it possible. In this context, other actors, agents and groups without tensions or conflicts and in differents conditions come into play different interests obtaining differents benefits. Also, the changes registered in recent patrimonialization wine are placed in historical perspective and at the construction of Cafayate as a tourist destination, which occurred in the 70s, and the reconversion of the 90s onwards. On the whole, a part of the work is stated in the review of institutional documents, tourist publicity brochures, local newspapers and consultation of websites, and the other part uses observation records and information obtained through interviews with municipal officials and agents private tourism sector.Fil: Villagran, Andrea Jimena. Universidad Nacional de Salta. Facultad de Humanidades. Centro Promocional de Investigaciones en Historia y Antropología "Dr. Guillermo B. Madrazo"; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Salta; Argentin