Calibración del número N de la curva de escurrimiento en una cuenca agropecuaria de 116 km2 de la provincia de Buenos Aires, Argentina

535-541In the mountainous area of Buenos Aires, Argentina, an increase in precipitation and in cultivated area has contributed to generating excessive runoff that has had severe impact on the region and on soil water erosion. The rain-runoff ratio in this region can help estimate the effects of floods. The local values of the runoff curve number (N) were calculated for the basin of the Arroyo Videla (Buenos Aires, Argentina), and its relationship to rainfall events was studied parting from daily rain data and runoff volumes. Values of 51 to 99 were obtained, and the most frequent were between 60 and 90. The relationship between N and precipitation exhibited a standard pattern that allowed adjusting an asymptotic value of 57. Rains less than 15 mm were associated with N between 85 and 90, while rains between 15 and 85 mm were related to N of 60 to 85. There was concordance between intermediate observed N and tabulated values of this parameter associated with each plant cover. This highlights the importance of obtaining local values of the studied variable to appropriately implement the method in basins of 100 km2

Calibración del número N de la curva de escurrimiento en una cuenca agropecuaria de 116 km2 de la provincia de Buenos Aires, Argentina

535-541In the mountainous area of Buenos Aires, Argentina, an increase in precipitation and in cultivated area has contributed to generating excessive runoff that has had severe impact on the region and on soil water erosion. The rain-runoff ratio in this region can help estimate the effects of floods. The local values of the runoff curve number (N) were calculated for the basin of the Arroyo Videla (Buenos Aires, Argentina), and its relationship to rainfall events was studied parting from daily rain data and runoff volumes. Values of 51 to 99 were obtained, and the most frequent were between 60 and 90. The relationship between N and precipitation exhibited a standard pattern that allowed adjusting an asymptotic value of 57. Rains less than 15 mm were associated with N between 85 and 90, while rains between 15 and 85 mm were related to N of 60 to 85. There was concordance between intermediate observed N and tabulated values of this parameter associated with each plant cover. This highlights the importance of obtaining local values of the studied variable to appropriately implement the method in basins of 100 km2

Thermodynamics of Extended Bodies in Special Relativity

Relativistic thermodynamics is generalized to accommodate four dimensional rotation in a flat spacetime. An extended body can be in equilibrium when its each element moves along a Killing flow. There are three types of basic Killing flows in a flat spacetime, each of which corresponds to translational motion, spatial rotation, and constant linear acceleration; spatial rotation and constant linear acceleration are regarded as four dimensional rotation. Translational motion has been mainly investigated in the past literature of relativistic thermodynamics. Thermodynamics of the other two is derived in the present paper.Comment: 8 pages, no figur

Second order equation of motion for electromagnetic radiation back-reaction

We take the viewpoint that the physically acceptable solutions of the Lorentz--Dirac equation for radiation back-reaction are actually determined by a second order equation of motion, the self-force being given as a function of spacetime location and velocity. We propose three different methods to obtain this self-force function. For two example systems, we determine the second order equation of motion exactly in the nonrelativistic regime via each of these three methods, the three methods leading to the same result. We reveal that, for both systems considered, back-reaction induces a damping proportional to velocity and, in addition, it decreases the effect of the external force.Comment: 13 page

How Do Nutritional Warnings Work on Commercial Products?

A large body of evidence assessing the effectiveness of front-of-package (FOP) nutrition labeling exists. Most experimental studies have been conducted with fictitious products. However, consumers? perception depends on several products extrinsic factors such as brand. Understanding how strong brand associations influence the effectiveness of FOP nutrition labeling schemes may be crucial to informing policymaking. In this context, the aim of this work was to evaluate the effect of five different variants of nutritional warnings labels (black magnifier, red magnifier, black octagon, black triangle, and red circle) on consumers? choice of commercial products, compared with two FOP nutrition labeling schemes: the guidelines daily amounts (GDAs) system and the traffic light system (TLS). An online randomized controlled trial with 1,932 participants was used to evaluate the effect of FOP nutrition labeling on participants? choices in eight sets of three commercial products, available in the Brazilian marketplace. A multinomial logistic regression model was used to evaluate the influence of FOP nutrition labeling on participants? likelihood of selecting the different products in the choice task. Results showed that nutritional warnings and the TLS significantly increased the likelihood of selecting none of the products instead of the least healthful product, or a healthier product, in at least one of the product categories compared with the GDA. Warnings tended to have a larger effect, suggesting their potential to encourage healthier food choices

Detection and Analysis of Anomalies in People Density and Mobility Through Wireless Smartphone Tracking

One of the challenges of this century is to use the data that a smart-city provides to make life easier for its inhabitants. Speci cally, within the area of urban mobility, the possibility of detecting anomalies in the movement of pedestrians and vehicles is an issue of vital importance for the planning and administration of a city. The aim of this paper is to propose a methodology to detect the movement of people from the information transmitted by their smart mobile devices, analyze these data, and be able to detect or recognize anomalies in their behavior. In order to validate this methodology, different experiments have been carried out based on real data aiming to extract knowledge, as well as obtaining a characterisation of the anomalies detected. The use of this methodology might help the city policy makers to better manage their mobility and transport resources.This work was supported by in part by the Dirección General de Tráfico under Project SPIP2017-02116, in part by the Ministerio de Ciencia, Innovación y Universidades under Grant RTI2018-102002-A-I00, in part by the Ministerio español de Economía y Competitividad under Grant TIN2017-85727-C4-2-P, in part by the FEDER under Grant TEC2015-68752, and in part by the FEDER y Junta de Andalucía under Project B-TIC-402-UGR18

Collective modes of coupled phase oscillators with delayed coupling

We study the effects of delayed coupling on timing and pattern formation in spatially extended systems of dynamic oscillators. Starting from a discrete lattice of coupled oscillators, we derive a generic continuum theory for collective modes of long wavelength. We use this approach to study spatial phase profiles of cellular oscillators in the segmentation clock, a dynamic patterning system of vertebrate embryos. Collective wave patterns result from the interplay of coupling delays and moving boundary conditions. We show that the phase profiles of collective modes depend on coupling delays.Comment: 5 pages, 2 figure

Geochemistry and Geochronology of the Guajira Eclogites, northern Colombia : evidence of a metamorphosed primitive Cretaceous Caribbean Island-arc

The chemical composition of eclogites, found as boulders in a Tertiary conglomerate from the Guajira Peninsula, Colombia suggests that these rocks are mainly metamorphosed basaltic andesites. They are depleted in LILE elements compared to MORB, have a negative Nb-anomaly and flat to enriched REE patterns, suggesting that their protoliths evolved in a subduction related tectonic setting. They show island-arc affinities and are similar to primitive islandarc rocks described in the Caribbean. The geochemical characteristics are comparable to low-grade greenschists from the nearby Etpana Terrane, which are interpreted as part of a Cretaceous intra-oceanic arc. These data support evidence that the eclogites and the Etpana terrane rocks formed from the same volcano-sedimentary sequence. Part of this sequence was accreted onto the margin and another was incorporated into the subduction channel and metamorphosed at eclogite facies conditions. 40Ar-39Ar ages of 79.2±1.1Ma and 82.2±2.5Ma determined on white micas, separated from two eclogite samples, are interpreted to be related to the cooling of the main metamorphic event. The formation of a common volcano-sedimentary protolith and subsequent metamorphism of these units record the ongoing Late Cretaceous continental subduction of the South American margin within the Caribbean intra-oceanic arc subduction zone. This gave way to an arc-continent collision between the Caribbean and the South American plates, where this sequence was exhumed after the Campanian