Effects of convection on the removal of the multiplicity of stable states in one-dimensional vertical models

Here I develop a model of a radiative-convective atmosphere with both radiative and convective schemes highly simplified. The atmospheric absorption of radiation at selective wavelengths makes use of constant mass absorption coefficients in finite width spectral bands. The convective regime is introduced by using a prescribed lapse rate in the troposphere. The main novelty of the radiative-convective model developed here is that it is solved without using any angular approximation for the radiation field. The solution obtained in the purely radiation mode (i. e. with convection ignored) leads to multiple equilibria of stable states, being very similar to some results recently found in simple models of planetary atmospheres. However, the introduction of convective processes removes the multiple equilibria of stable states. This shows the importance of taking convective processes into account even for qualitative analyses of planetary atmosphere

States of maximum entropy production in a onedimensional vertical model with convective adjustment

We investigate the hypothesis that the atmosphere is constrained to maximize its entropy production by using a one-dimensional (1-D) vertical model. We prescribe the lapse rate in the convective layer as that of the standard troposphere. The assumption that convection sustains a critical lapse rate was absent in previous studies, which focused on the vertical distribution of climatic variables, since such a convective adjustment reduces the degrees of freedom of the system and may prevent the application of the maximum entropy production (MEP) principle. This is not the case in the radiative–convective model (RCM) developed here, since we accept a discontinuity of temperatures at the surface similar to that adopted in many RCMs. For current conditions, the MEP state gives a difference between the ground temperature and the air temperature at the surface ≈10 K. In comparison, conventional RCMs obtain a discontinuity ≈2 K only. However, the surface boundary layer velocity in the MEP state appears reasonable (≈3 m s-¹). Moreover, although the convective flux at the surface in MEP states is almost uniform in optically thick atmospheres, it reaches a maximum value for an optical thickness similar to current conditions. This additional result may support the maximum convection hypothesis suggested by Paltridge (1978)

La renovación de los diarios digitales: rediseños y web 2.0

Se describen y analizan los cambios en los webs de diarios digitales españoles entre mayo y diciembre de 2006. Los principales son: la sustitución de la barra de navegación vertical por una barra horizontal superior, el diseño para una resolución de 1024 píxeles y el avance desigual en servicios de participación del lector. Se incluye una cronología de dichos cambios.

Vertical integration or specialisation: producing and commercialising cotton goods (1815-1913)

This article describes the ways in which cotton goods were commercialised during the nineteenth century and the first third of the twentieth. Several national cases are analysed: Britain, as the Workshop of the World; France, Germany, Switzerland and the US, as core economies; and Italy and Spain as countries on the European periphery. The main question that we address is why some cotton industries vertically integrated their production and commercialisation processes, but others did not. We present a model that combines industrial district size and product differentiation to explain why vertical integration was present in most cases and why there was vertical specialisation in Lancashire and Lowell.

Graduate labor mismatch in Central and Eastern Europe

[cat] Utilitzant l’enquesta REFLEX/HEGESCO, aquest article explora la probabilitat de desajustament entre educació i treball a l’Europa de l’Est i Central. Classifiquem els països en dos grups segons la transparència dels títols educatius al mercat de treball. Polònia, la República Txeca i Eslovènia formen el grup amb més transparència, i Hongria, Lituània i Estònia formen el grup amb més opacitat. Analitzem tres tipus de desajustaments: el vertical (infra‐, sobre‐educació), l’horitzontal (desajustament del camp d’estudi) i el desajust en habilitats. Focalitzem l’anàlisi en l’efecte dels camps d’estudi i les competències dels individus en el desajustament del mercat laboral en aquests països. Els resultats mostren importants diferències entre els dos grups de països estudiats.

Integer filling facfor phases and isospin in vertical diatomic artificial molecules

Integer filling factor phases of many-electron vertically coupled diatomic artificial quantum dot molecules are investigated for different values of the interdot coupling. The experimental results are analyzed within local-spin density functional theory for which we have determined a simple lateral confining potential law that can be scaled for the different coupling regimes, and Hartree-Fock theory. Maximum density droplets composed of electrons in both bonding and antibonding or just bonding states are revealed, and interesting isospin-flip physics appears for weak interdot coupling when the systematic depopulation of antibonding states leads to changes in isospin.

Dissociation of vertical semiconductor diatomic artificial molecules

We investigate the dissociation of few-electron circular vertical semiconductor double quantum dot artificial molecules at 0 T as a function of interdot distance. A slight mismatch introduced in the fabrication of the artificial molecules from nominally identical constituent quantum wells induces localization by offsetting the energy levels in the quantum dots by up to 2 meV, and this plays a crucial role in the appearance of the addition energy spectra as a function of coupling strength particularly in the weak coupling limit.

Vertical integration or specialisation: producing and commercialising cotton goods (1815-1913)

This article describes the ways in which cotton goods were commercialised during the nineteenth century and the first third of the twentieth. Several national cases are analysed: Britain, as the Workshop of the World; France, Germany, Switzerland and the US, as core economies; and Italy and Spain as countries on the European periphery. The main question that we address is why some cotton industries vertically integrated their production and commercialisation processes, but others did not. We present a model that combines industrial district size and product differentiation to explain why vertical integration was present in most cases and why there was vertical specialisation in Lancashire and Lowell.

Graduate labor mismatch in Central and Eastern Europe

[cat] Utilitzant l’enquesta REFLEX/HEGESCO, aquest article explora la probabilitat de desajustament entre educació i treball a l’Europa de l’Est i Central. Classifiquem els països en dos grups segons la transparència dels títols educatius al mercat de treball. Polònia, la República Txeca i Eslovènia formen el grup amb més transparència, i Hongria, Lituània i Estònia formen el grup amb més opacitat. Analitzem tres tipus de desajustaments: el vertical (infra‐, sobre‐educació), l’horitzontal (desajustament del camp d’estudi) i el desajust en habilitats. Focalitzem l’anàlisi en l’efecte dels camps d’estudi i les competències dels individus en el desajustament del mercat laboral en aquests països. Els resultats mostren importants diferències entre els dos grups de països estudiats.

La geotecnia vertical aplicada a la rehabilitación de yacimientos pleistocenos

La aplicación de una serie de técnicas propias de la geotecnia vertical y de la consolidación de taludes y laderas inestables se presenta por primera vez aplicada a la rehabilitación de yacimientos pleistocenos ubicados en antiguas canteras. Un conjunto de actuaciones especializadas permite garantizar la seguridad en los trabajos así como la preservación de la integridad de los yacimientos ubicados en cortes verticales y laderas rocosas. La rehabilitación realizada en el yacimiento de la Cova del Rinoceront (macizo del Garraf, NE de España), ubicado en el frente de explotación de una antigua cantera de piedra caliza, es el primer ejemplo conocido en la Península Ibérica donde la geotecnia vertical hasido utilizada en este tipo de contextos y, por lo tanto, los resultados pueden ser utilizados como un posible modelo de futuro para próximas intervenciones.

Pie plano astrágalo vertical asociado a sinovitis. Fases de tratamiento

El pie plano astrágalo vertical congénito es una deformidad poco frecuente que se puede encontrar de forma aislada, dentro de un cuadro polimalformativo o en relación con afectaciones neurológicas. Se caracteriza por una luxación del escafoides por encima del astrágalo,lo que provoca un pie rígido o de dificil manipulación. En este artículo los autores describen un caso clínico de un paciente que acude a consulta por presentar una inflamación dolorosa en la zona de la cabeza del astrágalo del pie derecho. Una vez realizado todo el protocolo exploratorio, se plantea la resolución mediante un plan de tratamiento en dos fases: una primera fase consistente en la realización de paracentesis evacuadora o terapéutica-curativa; y una segunda fase en la que se diseña tratamiento ortopodológlco de descarga.

Creation and Validation of Chronojump-Boscosystem: A Free Tool to Measure Vertical Jumps

Measuring the height of the vertical jump is an indicator of the strength and power of the lower body. The technological tools available to measure the vertical jump are black boxes and are not open to third-party verification or adaptation. We propose the creation of a measurement system called Chronojump-Boscosystem, consisting of open hardware and free software. Methods: A microcontroller was created and validated using a square wave generator and an oscilloscope. Two types of contact platforms were developed using different materials. These platforms were validated by the minimum pressure required for activation at different points by a strain gauge, together with the on/off time of our platforms in respect of the Ergojump-Boscosystem platform by a sample of 8 subjects performing submaximal jumps with one foot on each platform. Agile methodologies were used to develop and validate the software. Results: All the tools fall under the free software / open hardware guidelines and are, in that sense, free. The microcontroller margin of error is 0.1%. The validity of the fiberglass platform is 0.95 (ICC). The management software contains nearly 113.000 lines of code and is available in 7 languages.

Eficacia e ineficacia de la comunicación horizontal en los movimientos sociales. Caso análisis: Oposiciones justas en Cataluña 2011

Las redes sociales están generando un amplio entramado de comunicaciones, a distintos niveles y con distintos objetivos. En este artículo analizamos un caso concreto, fruto de la observación y el seguimiento de un grupo creado para la defensa de unas oposiciones justas para el acceso a la función pública de docentes para educación secundaria. Se trata de un grupo creado como reacción a una serie de posibles irregularidades. Interesa observar tanto la creación del grupo, como las distintas fases que sigue la evolución, muy ligada a la efectividad de los procesos de comunicación, y la vinculación de estos últimos a las posibilidades de acción y resolución del conflicto que existe en la base del grupo