Compaction and mobility in randomly agitated granular assemblies

We study the compaction and mobility properties of a dense granular material under weak random vibration. By putting in direct contact millimetric glass beads with piezoelectric transducers we manage to inject energy to the system in a disordered manner with accelerations much smaller than gravity, resulting in a slow compaction dynamics and no convection. We characterize the mobility inside the medium by pulling through it an intruder grain at constant velocity. We present an extensive study of the relation between drag force and velocity for different vibration conditions and sizes of the intruder.Comment: 4 pages, 6 figures, to appear in the proceedings of Powders and Grains 200

Noves dades sobre el mecanisme neural de la consolidació de la memòria: una oportunitat per a atenuar l’impacte emocional de les experiències traumàtiques

Durant la major part del segle xx, els estudis científics sobre la memòria assumien que les memòries eren immutables una vegada es consolidaven, tot i que podien perdre qualitat amb el pas del temps. Dades recents han revelat que les memòries, tot i estar ja consolidades, es tornen làbils durant la seua rememoració. Aquest descobriment implica que poden ser modificades i per tant emmagatzemades de nou amb aquestes modificacions. Aquestes investigacions obrin noves possibilitats d’intervenció en el camp del tractament de memòries emocionals resultants d’experiències traumàtiques, com ara el trastorn per estrés posttraumàtic. A més a més, dades experimentals indiquen que és possible utilitzar tant tractaments farmacològics com ara teràpies comportamentals.Durante la mayor parte del siglo xx, los estudios científicos sobre la memoria asumían que las memorias eran inmutables una vez se consolidaban, aunque podían perder calidad con el paso del tiempo. Datos recientes ha revelado que las memorias, a pesar de estar ya consolidadas, se vuelven lábiles durante su rememoración. Este descubrimiento implica que pueden ser modificadas y por tanto almacenadas de nuevo con estas modificaciones. Estas investigaciones abren nuevas posibilidades de intervención en el campo del tratamiento de memorias emocionales resultantes de experiencias traumáticas, como el trastorno por estrés postraumático. Además, resultados experimentales indican que es posible utilizar tanto tratamientos farmacológicos como terapias comportamentales.Pendant la plupart du xxe siècle, les études scientifiques sur la mémoire présupposaient que les mémoires étaient immuables une fois consolidées, mais qu’elles pouvaient perdre de la qualité au fil du temps. Des données récentes ont révélé que les mémoires, bien qu’elles soient déjà consolidées, deviennent labiles pendant leur souvenance. Cette découverte implique qu’elles peuvent être modifiées et donc entreposées de nouveau à partir de ces modifications. Ces recherches ouvrent de nouvelles possibilités d’intervention dans le domaine du traitement des mémoires émotionnelles résultantes des expériences traumatiques, comme le trouble de stress post-traumatique. D’ailleurs, certains résultats expérimentaux indiquent qu’il est possible d’utiliser soit des traitements pharmacologiques, soit des thérapies comportementales.During most of the twentieth century, scientific studies assumed that memories are unchangeable once consolidated, apart from quality loss over time. Recent data shows that, despite being consolidated, memories become labile when retrieved, which implies that they can be modified and stored with these modifications. This suggests new possibilities in the field of therapeutic treatment of emotional memories resulting from traumatic experiences, such as posttraumatic stress disorder. Moreover, experimental results indicate that both pharmacological and drug-free behavioural therapies may be useful

Dynamic and instability of submarine avalanches

We perform a laboratory-scale experiment of submarine avalanches on a rough inclined plane. A sediment layer is prepared and thereafter tilted up to an angle lower than the spontaneous avalanche angle. The sediment is scrapped until an avalanche is triggered. Based on the stability diagram of the sediment layer, we investigate different structures for the avalanche front dynamics. First we see a straight front descending the slope, and then a transverse instability occurs. Eventually, a fingering instability shows up similar to rivulets appearing for a viscous fluid flowing down an incline. The mechanisms leading to this new instability and the wavelength selection are discussed.Comment: 4 pages, 6 figures, to appear in the proceedings of Powders and Grains 200

Getting On Track With Green Growth: Exploring The Planning Of Transit- Oriented Communities

This paper explores the planning of Transit-Oriented Communities with a focus on two of Canada's most populous cities - Vancouver and Toronto. The current state of practice is investigated through case studies of the Cambie Corridor Plan in Vancouver and the Eglinton Connects Study in Toronto, aiming to uncover perspectives, challenges and success factors of these projects. Moreover, the research explores how sustainability beyond conventional Transit-Oriented Development practices is incorporated into the case studies, and whether these areas may result in what could be considered 'Green Transit-Oriented Development' – a term used for an enhanced ultra-environmentally friendly form of Transit-Oriented Development (TOD). The paper finds that these cities do well in terms of planning for Transit-Oriented Communities with the above projects, and transit-oriented planning efforts are supported by a solid policy framework at the regional and provincial levels. Both cities selected planning at the corridor scale as the preferred approach, as well as an emphasis on the shift to predominantly mid-rise development. Common initial challenges were exhibited in both cases, mainly in terms of partner collaboration and public engagement. Yet in the end, the establishment of strong partnerships and public involvement are also perceived as key success factors. Political support is recognized as a strongly influential factor, which can either stifle planning projects such as Cambie and Eglinton, or encourage them to become transformational opportunities. The influence from varying levels of political support is particularly illustrated with the ways the cities pursue sustainability. Beyond conventional transit-oriented development practices, the ambition and bold greening standards of Vancouver will see that the Cambie Corridor results in LEED gold development. In addition, Vancouver has capitalized on the anticipated redevelopment to ensure the integration of energy planning and promote a corridor serviced entirely by a low-carbon district energy network. Conversely, the Eglinton project displayed a mandate span that was limited in terms of advancing sustainability initiatives, and neither green building development nor energy planning were a part of the Study scope. Advanced green building is reliant upon incentives from the Toronto Green Standard Tier 2 achievements and the potential for district energy was seemingly overlooked. Thus, the paper concludes that Vancouver presents a leading example of synergistic planning that directs transit and low-carbon supported density, and better exhibits a green TOD-like endeavour. Finally, Toronto and other cities could learn from Vancouver and strive to improve sustainability goals, cultural commitment, and enabling planning policy

The Consequences of Mental Illness on Labor Market Decisions

The existing literature finds negative associations between mental illness and labor market outcomes. Using data from the 2007 to 2011 National Health Interview Survey, this study examines the consequences of emotional (depression, anxiety, or other emotional problems) and psychological (ADD, bipolar disorder, schizophrenia, or other mental problems) problems on four aspects of labor market decisions: the probability of participating in the labor force, the likelihood of working full time, the average number of hours worked per week and annual earnings. In addition to analyzing the effects of either having or not having a mental illness, I also test if there is a relationship between the duration of having a mental illness and labor market behaviors. I find evidence to show that having an emotional or psychological problem has an adverse impacts on all four aspects of labor market outcomes. Additionally, the results suggest that unconditional on having a mental illness, duration has statistically significant effects on labor market behaviors, while conditional on having a mental illness, statistical significance is not as prevalent

Inserción del eje transversal de gestión Integral de Riesgo y cambio Climático en las asignaturas de Seminario de formación integral y Sostenibilidad I, de las carreras de Administración de Empresa y Turismo Sostenible ambas del turno diurno.

La UNAN Managua, a través de la FAREM Estelí, ha tomado la iniciativa de capacitar a los docentes en las temáticas de inserción de ejes transversales, Gestión de Riesgo y Cambio Climático en las asignaturas que imparten en las diferentes carreras, para sensibilizar a la comunidad universitaria y contribuir al cambio de actitud frente al deterioro del medio ambiente. Para valorar la transversalización se utilizó la metodología de investigación acción, iniciando con un diagnóstico dirigido a docentes para conocer sus experiencias y a los estudiantes para valorar sus conocimientos previos en estas temáticas, encontrándose docentes preparados a través de capacitaciones y diplomados, encontramos y a los/as estudiantes que carecían de conocimientos en las mismas

Reorganization of a dense granular assembly: the `unjamming response function'

We investigate the mechanical properties of a static dense granular assembly in response to a local forcing. To this end, a small cyclic displacement is applied on a grain in the bulk of a 2D disordered packing under gravity and the displacement fields are monitored. We evidence a dominant long range radial response in the upper half part above the sollicitation and after a large number of cycles the response is `quasi-reversible' with a remanent dissipation field exhibiting long range streams and vortex-like symmetry.Comment: 5 pages, 5 figures, accepted version for publication in Phys. Rev.

Pharmaceuticals and personal care products in environmental waters

En la presente Tesis Doctoral se han desarrollado diferentes métodos analíticos para la determinación de pharmaceuticals and personal care products (PPCPs) en aguas medioambientales. El término PPCPs engloba todos los fármacos, drogas de abuso, hormonas y los excipientes activos incluidos en productos de uso personal, así como los metabolitos, conjugados y sub-productos de transformación. Los métodos desarrollados han estado basados en extracción en fase sólida o extracción con barras magnéticas agitadoras seguidos de la cromatografía líquida acoplada a la espectrometría de masas o de masas en tándem. Debido a los bajos límites de detección alcanzados, estos métodos se pudieron aplicar a la monitorización de estos compuestos en diferentes plantas depuradoras del área de Tarragona, donde la información al respeto era inexistente. Debido a que el principal destino de las aguas residuales son los ríos, se analizaron aguas del Ter, Llobregat y Ebro. Para completar el estudio, la presencia de PPCPs fue determinada en aguas de consumo.In the framework of the present Doctoral Thesis different analytical methods have been developed to determine pharmaceuticals and personal care products (PPCPs) in environmental waters. The term PPCPs cover all the pharmaceuticals, drugs of abuse, hormones, the active compounds included in personal care products, and also metabolites, conjugates and transformation sub-products. The developed methods were based on solid-phase extraction and stir bar sorptive extraction followed by liquid chromatography coupled to mass spectrometry and tandem mass spectrometry. Achieving the low limits of detection, these methods could be applied to the monitoring of these compounds in different sewage treatment plants from Tarragona Region, where not data were available. The PPCPs resulting in the effluent sewage waters can achieve rivers. Therefore, waters from three rivers: Ter, Llobregat and Ebro were analyzed. To complete the study, also drinking water was analyzed to determine PPCPs