El régimen internacional de la pesca de ballenas: Entre la conservación y la explotación (a propósito del asunto de la pesca de ballenas en el océano Antártico)

Australia ha demandado a Japón ante la Corte Internacional de justicia por el incumplimiento de sus obligaciones en relación con la pesca de ballenas y el comercio con los productos derivados de esta actividad. En su demanda, Australia invoca el régimen de la pesca de ballenas sobre la base de tres tratados internacionales: el Convenio Internacional de Regulación de la Pesca de Ballenas, la Convención Internacional sobre Comercio de Especies Amenazadas de Flora y Fauna Silvestres y el Convenio de Diversidad Biológica. Además solicita a la Corte que aplique estos tratados sistemáticamente y a la luz de las normas consuetudinarias que puedan haberse desarrollado en la materia. Se presenta una oportunidad para que la Corte se pueda pronunciar sobre las relaciones entre tratados internacionales, su interpretación y sus relaciones con las costumbres internacionales

ANÁLISIS FITOQUÍMICO Y ACTIVIDAD ANTIBACTERIAL DE EXTRACTOS METANÓLICOS DE Acrocomia aculeata: PALMA ADULTA Y GERMINADA in vitro

Objective: To evaluate the antibacterial effect of the methanolic extracts of different parts (leaf, stem and root) of the adult palm of Acrocomia acuelata and the palm germinated in vitro.Design / methodology / approximation: The phytochemical study was carried out by means of thin layer chromatography and visible light spectrophotometry; The diffusion method in well and microdilution in plate allowed to evaluate the antibacterial activity of the methanolic extracts, besides determining its cytopathic effect in MDCK cells. A simple variance analysis was performed applying a Tukey mean comparison test at the 5% confidence level.Results: The palm of A. aculeata was propagated in vitro from zygotic embryos. The methanolic extracts were obtained from adult and in vitro samples. The phytochemical study revealed the presence of flavonoids, coumarins, anthraquinones, saponins and tannins, being the methanolic extracts of A. aculeata adult the compounds with the highest phenolic content, and the only ones with bactericidal effect against the Gram+ strains studied, with halos of inhibition of 13 to 18mm. The MIC was determined between 125 to 250 mg gallic acid equivalents ? mL-1. The CC50 values were determined between 125 and 31.25 ug.mL-1.Limitations of the study / implications: For the CC50 values of the extracts of A. aculeata, it is recommended to use for the purpose of the test only the adult root extract and the in vitro extracts.Findings / conclusions: The methanolic extracts of adult A. acuelata have bactericidal activity against Gram+ strains, and a high content of phenolic compounds.Objetivo: Evaluar el efecto antibacteriano de los extractos metanólicos de diferentes partes (hoja, tallo y raíz) de la palma adulta de Acrocomia acuelata y la palma germinada in vitro.Diseño/metodología/aproximación: Se realizó el estudio fitoquímico mediante cromatografía en capa fina y espectrofotometría de luz visible; el método de difusión en pozo y microdilución en placa permitieron evaluar la actividad antibacterial de los extractos metanólicos, además se determinó su efecto citopático en células MDCK. Se realizó un análisis de varianza simple aplicando una prueba de comparación de medias de Tukey a un nivel del 5% de confianza.Resultados: Se propagó in vitro la palma de A. aculeata a partir de embriones cigóticos. Los extractos metanólicos se obtuvieron de muestras adultas e in vitro. El estudio fitoquímico reveló la presenciade flavonoides, cumarinas, antraquinonas, saponinas y taninos, siendo los extractos metanólicos de A. aculeata adulta los de mayor contenido de compuestos fenólicos, y los únicos con efecto bactericida frentea las cepas Gram+ estudiadas, con halos de inhibición de 13 a 18 mm. La CMI se determinó entre 125 a 250 mg equivalentes de ácido gálico?mL-1. Los valores de CC50 se determinaron entre 125 y 31.25ug.mL-1.Limitaciones del estudio/implicaciones: Por los valores de CC50 de los extractos de A. aculeata, se recomienda utilizar para pruebas posteriores únicamente el extracto de raíz adulta y los extractos in vitro.Hallazgos/conclusiones: Los extractos metanólicos de A. acuelata adulta tienen actividad bactericida frente a cepas Gram+, y un alto contenido de compuestos fenólicos

Comparación económica de dos modelos de jaulas para ponedoras utilizando una dieta comercial.

Ensayo con 336 días experimentales utilizando 224 aves livianas y 224 aves semipesadas de 20 semanas de edad, repartidas en jaula tradicional y en jaula reversible o modificada (42 cm de ancho por 30 cm de profundidad) con 3 y 4 aves por jaula. Se utiliza una dieta comercial de 16 por ciento de proteína. El objetivo es comparar los 2 tipos de jaulas en términos de producción de huevos, eficiencia y mortalidad; determinar la influencia del espacio del comedero y la densidad sobre el ingreso parcial tanto por ave como por jaula. No se presentaron diferencias estadísticas en cuanto a consumo entre los tratamientos, pero si una mejor conversión de la línea liviana en jaula reversible con 4 aves por jaula y mayor eficiencia de la línea semipesada en jaula reversible con 3 aves por jaula. La jaula reversible fue superior que la tradicional en porcentaje de producción gallina alojada en 3.05 por ciento. Con la línea liviana hubo 7.13 por ciento más de producción gallina alojada en jaula reversible que en jaula tradicional, presentando mayor ingreso neto parcial por jaula con esta línea en jaula reversible con 4 aves por jaula. Con la línea semipesada el más alto porcentaje de producción gallina alojada se obtuvo en jaula reversible con 3 aves por jaula, así como el mayor ingreso por ave y por jaula. No hubo diferencias de mortalidad entre los dos modelos de jaulas. Las correlaciones entre las variables fueron estudiadas; hubo una correlación altamente significativa entre la eficiencia alimenticia con el ingreso neto parcial por ave y por jaulaMaestría en CienciasMaestrí

Source time reversal (STR) method for linear elasticity

We study the problem of source reconstruction for a linear elasticity problem applied to seismicity induced by mining. We assume the source is written as a variable separable function $\mathbf{f(x)}\>g(t)$ . We first present a simple proof a local decay result for elasticity in the case of homogeneous media. We then extend the source time reversal method, originally developed for acoustic waves, to an elastic system of waves. Additionally, we present a fast reconstruction implementation for large data sets. This is especially useful in the elastic case, in which the numerical cost is higher than in fluid acoustics. We complement this work with several 2D and 3D numerical experiments and an analysis of the resultsThis work was partially supported by the European Union’s Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie Grant No 644602 GEAGAM (Spain) and CONICYT, Chile - PIA/Concurso de Apoyo a Centros Científicos y Tecnológicos de Excelencia con Financiamiento Basal AFB170001. Additionally, the first author was supported by CONICYT Doctoral fellowship number (Chile), Fondecyt11161033 (Chile), ICMP09-015-F (Chile), and EQM140119. Jaime H. Ortega was partially supported by Fondecyt1111012 and 1171854 (Chile). Ángel Rodríguez-Rozas and David Pardo were partially funded by the Projects of the Spanish Ministry of Economy and Competitiveness with reference MTM2016-76329-R (AEI/FEDER, EU) and MTM2016-81697-ERC/AEI, the BCAM “Severo Ochoa” accreditation of excellence SEV-2017-0718, the Basque Government through the BERC 2018-2021 program, the Consolidated Research Group Grant IT649-13 on “Mathematical Modeling, Simulation, and Industrial Applications (M2SI)”. David Pardo has also received funding from the European Union’s Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie grant agreement No 777778

Near IR diffraction-limited integral-field SINFONI spectroscopy of the Circinus galaxy

Using the adaptive optics assisted near infrared integral field spectrometer SINFONI on the VLT, we have obtained observations of the Circinus galaxy on parsec scales. The morphologies of the H_2(1-0)S(1) 2.12um and Br_gamma 2.17um emission lines are only slightly different, but their velocity maps are similar and show a gradient along the major axis of the galaxy, consistent with rotation.Since V_rot/sigma is approximately 1 suggests that random motions are also important, it is likely that the lines arise in a rotating spheroid or thickened disk around the AGN. Comparing the Br_gamma flux to the stellar continuum indicates that the star formation in this region began almost 10^8 yr ago. We also detect the [SiVI] 1.96um,[AlIX] 2.04um and [CaVIII] 2.32um coronal lines. In all cases we observe a broad blue wing, indicating the presence of two or more components in the coronal line region. A correlation between the ionisation potential and the asymmetry of the profiles was found for these high excitation species.Comment: 6 pages, 5 figures, Submitted to the Proceedings of the IFS Workshop, Jul 4-8 2005, Durham, Englan

Latitudinal Variation in the Toxicity and Sexual Compatibility of Alexandrium catenella Strains from Southern Chile

The bloom-forming toxic dinoflagellate Alexandrium catenella was first detected in southern Chile (39.5–55° S) 50 years ago and is responsible for most of the area’s cases of paralytic shellfish poisoning (PSP). Given the complex life history of A. catenella, which includes benthic sexual cysts, in this study, we examined the potential link between latitude, toxicity, and sexual compatibility. Nine clones isolated from Chilean Patagonia were used in self- and out-crosses in all possible combinations (n = 45). The effect of latitude on toxicity, reproductive success indexes, and cyst production was also determined. Using the toxin profiles for all strains, consisting of C1, C2, GTX4, GTX1, GTX3, and NeoSTX, a latitudinal gradient was determined for their proportions (%) and content per cell (pg cell−1), with the more toxic strains occurring in the north (−40.6° S). Reproductive success also showed a latitudinal tendency and was lower in the north. None of the self-crosses yielded resting cysts. Rather, the production of resting cysts was highest in pairings of clones separated by distances of 1000–1650 km. Our results contribute to a better understanding of PSP outbreaks in the region and demonstrate the importance of resting cysts in fueling new toxic events. They also provide additional evidence that the introduction of strains from neighboring regions is a cause for concern.En prens

The Degasperis-Procesi equation as a non-metric Euler equation

In this paper we present a geometric interpretation of the periodic Degasperis-Procesi equation as the geodesic flow of a right invariant symmetric linear connection on the diffeomorphism group of the circle. We also show that for any evolution in the family of $b$-equations there is neither gain nor loss of the spatial regularity of solutions. This in turn allows us to view the Degasperis-Procesi and the Camassa-Holm equation as an ODE on the Fr\'echet space of all smooth functions on the circle.Comment: 17 page

Continental shelf off northern Chilean Patagonia: A potential risk zone for the onset of Alexandrium catenella toxic bloom?

Harmful Algal Blooms (HAB) pose a severe socio-economic problem worldwide. The dinoflagellate species Alexandrium catenella produces potent neurotoxins called saxitoxins (STXs) and its blooms are associated with the human intoxication named Paralytic Shellfish Poisoning (PSP). Knowing where and how these blooms originate is crucial to predict blooms. Most studies in the Chilean Patagonia, were focused on coastal areas, considering that blooms from the adjacent oceanic region are almost non-existent. Using a combination of field studies and modelling approaches, we first evaluated the role of the continental shelf off northern Chilean Patagonia as a source of A. catenella resting cysts, which may act as inoculum for their toxic coastal blooms. This area is characterized by a seasonal upwelling system with positive Ekman pumping during spring-summer, and by the presence of six major submarine canyons. We found out that these submarine canyons increase the vertical advection of bottom waters, and thus, significantly enhance the process of coastal upwelling. This is a previously unreported factor, among those involved in bloom initiation. This finding put this offshore area at high risk of resuspension of resting cysts of A. catenella. Here, we discuss in detail the physical processes promoting this resuspension.Harmful Algal Blooms (HAB) pose a severe socio-economic problem worldwide. The dinoflagellate species Alexandrium catenella produces potent neurotoxins called saxitoxins (STXs) and its blooms are associated with the human intoxication named Paralytic Shellfish Poisoning (PSP). Knowing where and how these blooms originate is crucial to predict blooms. Most studies in the Chilean Patagonia, were focused on coastal areas, considering that blooms from the adjacent oceanic region are almost non-existent. Using a combination of field studies and modelling approaches, we first evaluated the role of the continental shelf off northern Chilean Patagonia as a source of A. catenella resting cysts, which may act as inoculum for their toxic coastal blooms. This area is characterized by a seasonal upwelling system with positive Ekman pumping during spring-summer, and by the presence of six major submarine canyons. We found out that these submarine canyons increase the vertical advection of bottom waters, and thus, significantly enhance the process of coastal upwelling. This is a previously unreported factor, among those involved in bloom initiation. This finding put this offshore area at high risk of resuspension of resting cysts of A. catenella. Here, we discuss in detail the physical processes promoting this resuspension.Postprint2,35

The role of physico-chemical interactions in the seasonality of toxic dinoflagellate cyst assemblages: The case of the NW Patagonian fjords system

Harmful algal blooms (HABs) are recurrent in the NW Patagonia fjords system and their frequency has increased over the last few decades. Outbreaks of HAB species such as Alexandrium catenella, a causal agent of paralytic shellfish poisoning, and Protoceratium reticulatum, a yessotoxins producer, have raised considerable concern due to their adverse socioeconomic consequences. Monitoring programs have mainly focused on their planktonic stages, but since these species produce benthic resting cysts, the factors influencing cyst distributions are increasingly gaining recognition as potentially important to HAB recurrence in some regions. Still, a holistic understanding of the physico-chemical conditions influencing cyst distribution in this region is lacking, especially as it relates to seasonal changes in drivers of cyst distributions as the characteristics that favor cyst preservation in the sediment may change through the seasons. In this study, we analyzed the physico–chemical properties of the sediment (temperature, pH, redox potential) and measured the bottom dissolved oxygen levels in a “hotspot” area of southern Chile, sampling during the spring and summer as well as the fall and winter, to determine the role these factors may play as modulators of dinoflagellate cyst distribution, and specifically for the cysts of A. catenella and P. reticulatum. A permutational analysis of variance (PERMANOVA) showed the significant effect of sediment redox conditions in explaining the differences in the cyst assemblages between spring-summer and fall-winter periods (seasonality). In a generalized linear model (GLM), sediment redox potential and pH were associated with the highest abundances of A. catenella resting cysts in the spring-summer, however it was sediment temperature that most explained the distribution of A. catenella in the fall-winter. For P. reticulatum, only spring-summer sediment redox potential and temperature explained the variation in cyst abundances. The implications of environmental physico-chemical seasonality for the resting cysts dynamics of both species are discussed.Postprint3,74