The Lagrangian description of aperiodic flows: a case study of the Kuroshio Current

This article reviews several recently developed Lagrangian tools and shows how their combined use succeeds in obtaining a detailed description of purely advective transport events in general aperiodic flows. In particular, because of the climate impact of ocean transport processes, we illustrate a 2D application on altimeter data sets over the area of the Kuroshio Current, although the proposed techniques are general and applicable to arbitrary time dependent aperiodic flows. The first challenge for describing transport in aperiodical time dependent flows is obtaining a representation of the phase portrait where the most relevant dynamical features may be identified. This representation is accomplished by using global Lagrangian descriptors that when applied for instance to the altimeter data sets retrieve over the ocean surface a phase portrait where the geometry of interconnected dynamical systems is visible. The phase portrait picture is essential because it evinces which transport routes are acting on the whole flow. Once these routes are roughly recognised it is possible to complete a detailed description by the direct computation of the finite time stable and unstable manifolds of special hyperbolic trajectories that act as organising centres of the flow.Comment: 40 pages, 24 figure

The hidden geometry of ocean flows

We introduce a new global Lagrangian descriptor that is applied to flows with general time dependence (altimetric datasets). It succeeds in detecting simultaneously, with great accuracy, invariant manifolds, hyperbolic and non-hyperbolic flow regions.Comment: 4 pages, 4 figure

The turnstile mechanism across the Kuroshio current: analysis of dynamics in altimeter velocity fields

In this article we explore the ability of dynamical systems tools to describe transport in oceanic flows characterized by data sets measured from satellite. In particular we have studied the geometrical skeleton describing transport in the Kuroshio region. For this purpose we have computed special hyperbolic trajectories, recognized as distinguished hyperbolic trajectories, that act as organizing centres of the flow. We have computed their stable and unstable manifolds, and they reveal that the turnstile mechanism is at work during several spring months in the year 2003 across the Kuroshio current. We have found that near the hyperbolic trajectories takes place a filamentous transport front-cross the current that mixes waters at both sides.Comment: Nonlinear Processes in Geophysics 17, 2010 (in press

Sustainable Development & Food Reinventing the school meal through public procurement practices: The case of Malmö

The importance of food on achieving sustainability has been a topic increasingly moved to the forefront of the international debate. Thus, governments from around the globe have developed and adopted comprehensive food policies aiming at sustainable development. As part of this, public procurement has been identified as a powerful tool leveraging government’s purchasing power and holding an interesting potential to re-shape the food markets. Simultaneously, the school meals program represents the ultimate arena where the addition of efforts striving for sustainable food systems has to find its culmination since it involves the wellbeing of the most vulnerable sector of the population. For this reason, it becomes important to understand the prevalent conditions determining the procurement decisions of school’s catering personnel regarding sustainable sound foodstuffs. The purpose of this thesis is to do an exploratory research of the preschool catering sector in Malmö in order to identify the conditions shaping their procurement decisions with a special focus on organic foodstuffs, resulting from the enactment of a policy for sustainable development and food on 2010. The findings of this investigation aim at providing a deeper understanding of the key factors influencing the purchasing behavior of the cooking staff and how this information can be further employed to motivate the sector towards the attainment of the policy goals. A desktop literature review on the topic, basic statistics and qualitative interviews with involved participants were collected in order to gain deeper insight on the case of Malmö. The information was then analyzed using a modified version of the GPP Hurdle Analysis tool developed by Günther & Scheibe (2006). It was identified that food indeed is in itself a powerful tool persistently involved on the core intrinsic concepts of sustainable development. Simultaneously, coupling the abilities of public caterers with sustainability concerns and applying those on the fertile arena of preschools via the meals program holds a promise that turns out to be more than appealing. If sustainable public catering efforts are applied together with a strategy to educate the youth so to raise their awareness and instill a mentality of sustainability through food, the cycle will be closed from both ends of supply and demand. Even when it seems unlikely that a universally valid strategy for overcoming obstacles for sustainable procurement on the catering sector can be developed, individual strategies can be designed as long as the proper information is made available and motivation is stirred adequately

Evaluación del estado fitopatológico del agraz (Vaccinium meridionale sw) en localidades del altiplano cundiboyacense (dos de Boyacá y una de Cundinamarca)

Aislar e identificar los posibles patógenos presentes en la porción aérea del agraz (V. meridionale). A partir de lesiones en el vástago de agraz, aislar e identificar los posibles patógenos. Utilizando los organismos aislados, comprobar los postulados de Koch para determinar la relación patógeno lesiónPregrad

Análisis de la experiencia del usuario mediante mediciones sensoriales en momentos de consumo

El mercadeo experiencial se basa en tres componentes fundamentales: la organización, la experiencia del usuario y las personas -- La organización es la encargada de definir el contexto en el que una experiencia se llevará a cabo -- Las personas se ven como seres racionales y emocionales y el mercadeo da prioridad a lo emocional y, por lo tanto, busca maneras de medir las emociones -- Por último, la experiencia del usuario, que constituye un suceso construido de manera individual por cada persona -- En el presente estudio se evalúa la experiencia del usuario en el restaurante El Cielo, que representa una experiencia gastronómica única en Colombia, debido a la combinación de creatividad y cocina de autor, con el mercadeo experiencial, lo que lo posiciona como un referente en el enfoque del mercadeo posmoderno -- La metodología aplicada para llevar a cabo el trabajo consta de dos sesiones in situ y entrevistas en profundidad que incluyen rueda de Plutchick y el gráfico de los cinco sentidos, con el fin de medir las emociones y el involucramiento de los sentidos, en su orden -- La información se triangulará a partir de las siguientes herramientas: Q sensor y Emotiv, que son dos marcas de equipos tecnológicos usados en neuromarketin

Added phosphorus availability and re-distribution in both natural and cultivated vertisols

The fates of both native and added phosphorus were studied in a Leptic Hapludert, by Hedley´s fractionation method. The objectives of this study were to: a) assess the reaction of a natural grassland and a cultivated grassland in a Vertisol with added P by fertilization; b) to study the association between inorganic and organic P labile, moderately labile or non-labile forms with P availability for ryegrass growth; c) to test whether ryegrass growth may reflect the effect of a release of P from the soil with the incubation. Soil samples were taken from: a) Natural soil and, b) Cultivated soil that had been fertilized with 120 kg ha-1 yr-1 of TSP. In the laboratory, one group of samples was fertilized with P (0-200 mg P kg-1) and then incubated 25 days at 28 oC. The other group was also fertilized with P but was not incubated. After P fractionation,, ryegrass was grown in a greenhouse 45 days and the dry yield of shoots was measured. Inorganic labile P forms increased with the level of added P in both soils, and these forms were closely associated with ryegrass growth. The inorganic resistant P forms also increased with the level of added P in both soils, but more P was removed from the incubated samples suggesting that part of the added P was redistributed during the incubation. For both soils, the organic labile P decreased with the level of addition in the incubated samples but increased in the non-incubated samples. The organic more resistant P forms did not differ between the natural and cultivated soil and did not show a consistent distribution with added P or incubation. This suggests that these P forms had little influence on P availability in short or medium periods of reaction between soil and P.Fil: Fernandez Lopez, Carolina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales; Argentina; Universidad Nacional del Nordeste. Facultad de Ciencias Agrarias; Argentina;Fil: Mendoza, Rodolfo Ernesto. Museo Argentino de Ciencias Naturales; Argentina

Potential Phytoremediator of Native Species in Soils Contaminated by Heavy Metals in the Garbage Dump Quitasol-Imponeda Abancay

Discarding waste in open spaces, commonly called dumps, is highly damaging to the environment. High concentrations of heavy metals are observed, which creates the need to carry out restoration processes in such places. The use of plants for the remediation of soils contaminated by heavy metals in the garbage dump, is a strategy. The work was carried out in the garbage dump of Quitasol-Imponeda de Abancay, with three native plant species. The objective was to evaluate the levels of contamination by the heavy metals: lead, cadmium, nickel, chromium and zinc in the waste matrix in root, stem and leaves. A complete factorial design was applied: three species and five treatments with heavy metals, each with two repetitions applied and in three selected plots (A, B, C). The results show that the highest accumulation of zinc, lead and cadmium was obtained in Amaranthus hybridus, with 23.03 parts per million in the root, 5.87 parts per million in the stem and 8.83 parts per million in the leaves, in plots two and three. In Brassica rapa, the highest values of accumulation were recorded for zinc, lead and cadmium in the roots, and showed a decrease in leaf growth and stem thickness. Amaranthus spinosus obtained higher values of zinc accumulation of 24.28 parts per million in the roots and in leaves, zinc 11.63 parts per million, lead 1.74 parts per million and cadmium 0.55 parts per million. It is concluded that the three native species present rapid growth, do not require chemical controls, with absorption of high levels of heavy metals, becoming an alternative for the restoration of the garbage dump, due to its high phytoremediation potential

Lagrangian skeleton on the Gulf of Mexico oil spill

The understanding of the circulation of ocean currents, the exchange of CO2 between atmosphere and oceans, and the influence of the oceans on the distribution of heat on a global scale is key to our ability to predict and assess the future evolution of climate [1, 2]. Global climate change is affecting sea breathing through mechanisms not yet understood