RETRASO, a code for modeling reactive transport in saturated and unsaturated porous media

The code RETRASO (REactive TRAnsport of SOlutes) simulates reactive transport of dissolved and gaseous species in non-isothermal saturated or unsaturated problems. Possible chemical reactions include aqueous complexation (including redox reactions), sorption, precipitation-dissolution of minerals and gas dissolution. Various models for sorption of solutes on solids are available, from experimental relationships (linear KD, Freundlich and Langmuir isotherms) to cation exchange and surface complexation models (constant capacitance, diffuse layer and triple layer models). Precipitation-dissolution and aqueous complexation can be modelled in equilibrium or according to kinetic laws. For the numerical solution of the reactive transport equations it uses the Direct Substitution Approach. The use of the code is demonstrated by three examples. The first example models various sorption processes in a smectite barrier. The second example models a complex chemical system in a two dimensional cross-section. The last example models pyrite weathering in an unsaturated medium

Abelianization of First Class Constraints

We show that a given set of first class constraints becomes abelian if one maps each constraint to the surface of other constraints. There is no assumption that first class constraints satisfy a closed algebra. The explicit form of the projection map is obtained at least for irreducible first class constraints. Using this map we give a method to obtain gauge fixing conditions such that the set of abelian first class constraints and gauge fixing conditions satisfy the symplectic algebra.Comment: To appear in PL

Overcoming TGFβ-mediated immune evasion in cancer

This Review discusses the context-dependent functions of transforming growth factor-beta (TGF beta) with regard to the composition and behaviour of different cell populations in the tumour immune microenvironment, as well as emerging data that demonstrate that TGF beta inhibition can restore cancer immunity. Transforming growth factor-beta (TGF beta) signalling controls multiple cell fate decisions during development and tissue homeostasis; hence, dysregulation of this pathway can drive several diseases, including cancer. Here we discuss the influence that TGF beta exerts on the composition and behaviour of different cell populations present in the tumour immune microenvironment, and the context-dependent functions of this cytokine in suppressing or promoting cancer. During homeostasis, TGF beta controls inflammatory responses triggered by exposure to the outside milieu in barrier tissues. Lack of TGF beta exacerbates inflammation, leading to tissue damage and cellular transformation. In contrast, as tumours progress, they leverage TGF beta to drive an unrestrained wound-healing programme in cancer-associated fibroblasts, as well as to suppress the adaptive immune system and the innate immune system. In consonance with this key role in reprogramming the tumour microenvironment, emerging data demonstrate that TGF beta-inhibitory therapies can restore cancer immunity. Indeed, this approach can synergize with other immunotherapies - including immune checkpoint blockade - to unleash robust antitumour immune responses in preclinical cancer models. Despite initial challenges in clinical translation, these findings have sparked the development of multiple therapeutic strategies that inhibit the TGF beta pathway, many of which are currently in clinical evaluation

Oligodendroglioma anaplásico en el nervio óptico de un perro

Los gliomas son tumores no neuronales del tejido nervioso. En el Sistema Nervioso Central (SNC) dependiendo de su origen se clasifican en astrocitomas, oligodendrogliomas, tumores mixtos (oligoastrocitomas), ependimomas y papilomas de plexos coroideos. La retina y el nervio óptico pertenecen al SNC. Aunque las neoplasias primarias de la retina y el nervio óptico son bastante infrecuentes, son los meningiomas los tumores primarios más comunes siendo los gliomas más raros

Canonical Noether symmetries and commutativity properties for gauge systems

For a dynamical system defined by a singular Lagrangian, canonical Noether symmetries are characterized in terms of their commutation relations with the evolution operators of Lagrangian and Hamiltonian formalisms. Separate characterizations are given in phase space, in velocity space, and through an evolution operator that links both spaces.Comment: 22 pages; some references updated, an uncited reference deleted, minor style change

Revitalización de antiguos cuarteles a partir de un nuevo espacio climático. Criterios para la reducción de la demanda energética. Parque Científico Tecnológico Agroalimentario “PCiTAL”. Gardeny. Lleida. Consorcio “PCital” (Univ. Lérida-Ayuntamiento Lérida)

The rehabilitation-revitalization of some old headquarters, situated in Gardeny area in the city of Lérida, consisted of the intervention in three existing buildings and there restructuring in investigation spaces for the university and the food and agriculture business. In project decisions, were considered to be a priority, the buildings energy demand improvement. For it, during the project phase, data processing models and storage of the existing building climatic information were used. The information and calculations fitted project and they have been the base to motorize and to monitor the rehabilitated building. In phase of preliminary design, and to the buildings energy demand improvement, the asoociated energy demand to the constructive and architectural characteristics of the building, were evaluated by means of energy models. The constructive systems solutions, atrium-spaces, and the humidity and vegetation effect, permitted savings around 23% in heating and 50% in cooling. The possibility to integrate a second research team in the project allowed us to arrange on one hand the data of savings and for other one monitoring the existing building. As well we programmed the rehabilitated (and in use) building monitoring. Nowadays, on a developed methodology, bioclimatic strategies are being adjusted to give the ideal comfort to the interiors and intermediate spaces of the buildings.La rehabilitación-revitalización de unos antiguos cuarteles, situados en el área de Gardeny en la ciudad de Lérida, consistió en la intervención en tres edificios existentes y reconvertirlos en espacios de servicio a la investigación para la universidad y la empresa agroalimentaria. Se consideraron como prioridad, en las decisiones de proyecto, la mejora de la demanda energética de los edificios, para ello se utilizaron modelos informáticos, en la fase de proyecto, y monitorización, de los edificios existentes. Los datos y cálculos ajustaron las decisiones de proyecto y han sido la base para motorizar y monitorizar el edificio finalizado. En fase de anteproyecto se evaluó mediante modelos energéticos la demanda energética asociada a las características arquitectónicas y constructivas del edificio para poder decidir las posibilidades de reducción. Las decisiones sobre los sistemas constructivos, los espacios-atrio y el efecto de humedad y vegetación nos permitían un ahorro en torno a un 23% en calefacción y un 50% en refrigeración. La posibilidad de integrar a un segundo grupo de investigación en el proyecto permitió por un lado cotejar los datos de ahorro y por otro monitorizar el edificio existente y así como programar la monitorización del edificio ya rehabilitado y en uso. Actualmente, sobre una metodología desarrollada, se están ajustando las estrategias bioclimáticas de control para dar el confort óptimo a los espacios intermedios e interiores de los edificios

Targeting the Microenvironment in Advanced Colorectal Cancer

Colorectal cancer (CRC) diagnosis often occurs at late stages when tumor cells have already disseminated. Current therapies are poorly effective for metastatic disease, the main cause of death in CRC. Despite mounting evidence implicating the tumor microenvironment in CRC progression and metastasis, clinical practice remains predominantly focused on targeting the epithelial compartment. Because CRCs remain largely refractory to current therapies, we must devise alternative strategies. Transforming growth factor (TGF)-β has emerged as a key architect of the microenvironment in poor-prognosis cancers. Disseminated tumor cells show a strong dependency on a TGF-β-activated stroma during the establishment and subsequent expansion of metastasis. We review and discuss the development of integrated approaches focused on targeting the ecosystem of poor-prognosis CRCs

Concepción y realización de celosías cerámicas, una evolución constructiva

This paper analyzes several ceramic lattices, designed and developed by the architectural firm Picharchitects together with different industries. The paper tries to point out some of this construction system’s particularities in relation with its environmental behavior and technological development. At the same time the paper introduces some reflections about the lattices as a combination of different and diverse components that have been implemented along several construction technics and architectural functionalities. Moreover the paper tries to introduce some hypothesis about the construction system invariabilities (as an essences of the system itself) and some of its possible evolutions.El presente artículo analiza diversas celosías cerámicas, realizadas por el equipo de arquitectura Pich-Aguilera en colaboración con diversas industrias, tratando de ilustrar particularidades en su comportamiento ambiental y su desarrollo tecnológico. Mediante dicho análisis el trabajo trata de reflexionar sobre el sistema constructivo de la celosía cerámica como el resultado de la combinación de componentes y sistemas cerámicos muy diversos, implementados a lo largo del tiempo en distintas tipologías constructivas y funcionales. Paralelamente el estudio apunta algunas hipótesis acerca de las invariantes esenciales del propio sistema y de posibles evoluciones futuras