Abstract: This paper explores the possibilities that arise from the recent judgment of the International Court of Justice at The Hage, under which the aforementioned Court declares that has jurisdiction to entertain the Application filed by the Plurinational State of Bolivia on April 2013 against the Republic of Chile. According to this Application, Chile would be obliged to negotiate in good faith with Bolivia in order to reach a fully sovereign access to the Pacific Ocean. According to that statement four questions should try to be answered: i. ¿What is the meaning of good faith in the field of international law?; ii. ¿What is the scope of the term “be obliged to negotiate in good faith”?; iii. What has been the jurisprudence of the Court on this matter?, and, iv. ¿What can be expected from the judgment of the International Court of Justice according to the theory, practice and international jurisprudence?

Resumen: Este trabajo explora las posibilidades que abre el reciente fallo de la Corte Internacional de Justicia de La Haya, conforme al cual la referida Corte se declara competente para conocer de la demanda presentada por el Estado Plurinacional de Bolivia, en abril del año 2013, en contra de la República de Chile. En virtud de esta demanda Chile estaría obligado a negociar de buena fe una salida soberana al océano Pacífico en favor de Bolivia. A propósito de dicho pronunciamiento, se intenta dar respuesta a cuatro interrogantes: i. ¿cuál es el sentido de la expresión “buena fe” en el dominio del derecho internacional público?; ii. ¿cuál es el alcance de la expresión “estar obligado a negociar de buena fe”?; iii. ¿cuál ha sido la jurisprudencia de la Corte en esta materia?, y iv. ¿qué se puede esperar del fallo de la Corte Internacional de Justicia a la luz de la teoría, la práctica y la jurisprudencia internacionales?

A 5-year-old boy presented to hospital with mild local cytotoxic and severe neurotoxic symptoms. The neurotoxic symptoms included ptosis, fixed dilated pupils and flaccid paralysis with respiratory failure. Mild hyponatraemia was also a clinical feature. After various unsuccessful treatment options were followed, the Tygerberg Poison Information Centre was contacted and a diagnosis of berg adder bite was made. Berg adder bites are uncommon and therefore not usually considered in the differential diagnosis of a patient presenting with an unexplained clinical picture. A timeous poison information helpline consultation is recommended in this situation.

Resumo Durante o período de 2010-2012, oitenta espécimes de Calidris fuscicollis (Vieillot, 1819) foram coletados na costa sul do Estado do Rio Grande do Sul, com o objetivo de determinar a presença de ácaros de pena. Das 80 aves examinadas, 32,5% estavam infestadas por ácaros, os quais foram identificados como Avenzoaria calidridis (Oudemans, 1904) (Avenzoariidae) (31,25%), Montchadskiana securicata (Megnin & Trouessart 1884) (Pterolichidae) (22,5%) e Alloptes limosae (Dubinin, 1951) (Alloptidae) (6,25%). Este é o primeiro relato de ácaros de pena em Calidris fuscicollis no Brasil.

Abstract During the period 2010-2012, eighty individuals of Calidris fuscicollis (Vieillot, 1819) were collected on the southern coast of Rio Grande do Sul, Brazil, with the objective of determining the presence of feather mites. Of the 80 birds examined, 32.5% were infested by mites, identified as Avenzoaria calidridis (Oudemans, 1904) (Avenzoariidae) (31.25%), Montchadskiana securicata (Megnin & Trouessart 1884) (Pterolichidae) (22.5%) and Alloptes limosae (Dubinin, 1951) (Alloptidae) (6.25%). This is the first report of feather mites on Calidris fuscicollis in Brazil

The purpose of this study is to investigate the change in the atmospheric circulation associated with frost events in the Wet Pampa (WP) in the future climate for the most critical scenarios projected by the GFDL ocean-atmosphere coupled model. Two versions of the GFDL model are used, the GFDL-CM2 for CMIP3 and GFDL-CM3 for CMIP5. We analyze the model capability to simulate the five most extreme cold events in the present climate (1961-1990), with respect to those obtained with the NCEP/NCAR Reanalysis. Then, we compare the future climate simulations (2081-2100) with the model simulation for the present climate. For the present climate the CMIP3 experiment presents more penetration of the 0°C isotherm in 850 hPa, intensifying the negative temperature anomalies in comparison to the reanalysis. The postfrontal anticyclone is more meridionally extended over the continent, with similar anomalies to those of the reanalysis, mainly over WP. The gradient between the high pressure and the low pressure downwind creates a more intense southerly cold airflow at 850 hPa than the reanalysis, giving place to advective frosts in the studied region. For the future climate, the model projects less penetration of the 0°C isotherm and less intense negative temperature anomalies. The anticyclone maximum is located further north than in the present climate, propitiating radiative frosts. In the upper levels, the subtropical jet shows a more zonally layout and slightly higher intensity than in the present climate simulations. For the present climate the CMIP5 experiment simulates well the incursion of the 0°C isotherm, although with a more intense temperature anomaly in comparison to the reanalysis. The pressure field presents similar characteristics to those shown in the CMIP3 experiment, but with larger anomalies in the southern part of the continent. For the future scenario, the model projects the 0°C isotherm incursion as well as the negative temperature anomalies similar to the present. The post frontal anticyclone is located further north, overestimating its value and the anomaly over WP. The wind field is similar to the present simulation. Summarizing the results of both experiments, the future projections with CMIP3 show significant changes with respect to the present, which is not the case with the CMIP5 experiment. These changes are mainly reflected in the pressure field, in which the position of the anticyclone in CMIP3 (CMIP5) would favor radiative (advective) frosts over WP.

El propósito de este estudio es investigar los cambios en la circulación atmosférica asociados a eventos de heladas en la Pampa Húmeda (PH) en el clima futuro para los escenarios más críticos proyectados por el modelo acoplado oceano-atmósfera GFDL. Se emplea el modelo GFDL en sus dos versiones (GFDL-CM2 para el CMIP3 y GFDL-CM3 para el CMIP5). Se analiza la capacidad del modelo para simular los cinco eventos extremos más fríos en el clima presente (1961-1990), respecto de los obtenidos en el reanálisis del NCEP/NCAR. Luego se comparan las simulaciones del clima futuro (2081-2100) con las del presente. En el experimento CMIP3 del clima presente el modelo muestra una mayor penetración de la isoterma de 0°C en 850 hPa, con anomalías de temperatura negativas más intensas que las del NCEP. El anticiclón pos frontal se observa más extendido meridionalmente sobre el continente, con valores de anomalías similares principalmente en la Pampa Húmeda. El gradiente de presión entre la alta y la baja corriente abajo, provoca un flujo de aire frio del sur más intenso en 850 hPa que en el reanálisis, propiciando heladas del tipo advectivas en la región de estudio. En el clima futuro el modelo proyecta una menor incursión de la isoterma de 0°C y con anomalías negativas de temperatura más pequeñas. El máximo del anticiclón en el futuro se localiza más al norte que en el presente, propiciando heladas del tipo radiativas. En el campo de altura, el jet subtropical se presenta más zonal y con intensidades ligeramente mayores que en las simulaciones del clima presente. Para el experimento CMIP5 en el clima presente el modelo logra simular la incursión de la isoterma de 0°C, pero la anomalía de temperatura es mayor que en el reanálisis. El campo de presión presenta similares características que en el experimento de CMIP3, pero con anomalías más intensas al sur del continente. En el escenario futuro el modelo proyecta la incursión de la isoterma de 0°C, así como la anomalía negativa de temperatura, similares al presente. El anticiclón pos frontal se localiza más al norte, sobrestimando tanto su valor así como su anomalía en la PH. El campo de viento no muestra diferencias respecto del presente. En suma, comparando los dos experimentos, el de CMIP3 en el futuro muestra importantes cambios respecto al presente, lo que no ocurre en el CMIP5. Esos cambios se ven principalmente en el campo de presión, donde para el CMIP3 (CMIP5) las heladas tipo radiativas (advectivas) serían las favorecidas en la Pampa Húmeda debido a la posición del anticiclón.

Foram examinadas 81 aves Tyraniidae, 80 Pitangus sulphuratus (Linnaeus, 1766) (Bem-te-vi) e um Machetornis rixosa (Vieilot, 1819) (Suiriri-cavaleiro) para coleta de ácaros nasais, os quais foram identificados como Ptilonyssus spinosus (Brooks & Strandtmann, 1960) e Sternostoma longisetosae (Hyland, 1961) (Rhinonyssidae). Este achado caracteriza o primeiro relato de P. spinosus e S. longisetosae em P. sulphuratus e o primeiro registro de P. spinosus em M. rixosa, e amplia a distribuição geográfica destas espécies, sendo a primeira ocorrência de S. longisetosae na região neotropical e primeira citação de P. spinosus no Rio Grande do Sul, Brasil.

A total of 81 Tyraniidae birds were examined, 80 Pitangus sulphuratus (Linnaeus, 1766) (Great kiscadee), and one Machetornis rixosa (Vieilot, 1819) (Cattle tyrant), for collection of nasal mites, which were identified as Ptilonyssus spinosus (Brooks & Strandtmann, 1960) and Sternostoma longisetosae (Hyland, 1961) (Rhinonyssidae). This finding characterises the first report of P. spinosus and S. longisetosae in P. sulphuratus, and the first record of P. spinosus in M. rixosa, and expands the geographic distribution of these species. It is the first occurrence of S. longisetosae in the Neotropics, and the first citation of P. spinosus in the state of Rio Grande do Sul, Brazil.

BACKGROUND: The incidence and spectrum of acute poisonings in South Africa are unknown. Poisoning data can be derived from sources such as hospital admission records and poison information centre (PIC) records. OBJECTIVES: This study was conducted to examine the extent of the problem and to identify trends and toxicovigilance issues using PIC data. METHODS: A survey was conducted based on Tygerberg Poison Information Centre (TPIC) consultations over 1 year. TPIC consultation forms were analysed for patient demographics and causes of poisoning. RESULTS: The TPIC dealt with 4 771 consultations related to human exposures to poisonous substances. The study showed that accidental exposure was more common than intentional poisoning (65.2% v. 34.8%); that 55.8% of cases were adults, of which 57.6% were females; and that 61.4% of adult cases were intentional exposures, and of these 64.3% were females. There was a predominance of accidental exposures (98.8%) and a male predominance (59.7%) in children. Categories of poisoning exposures across all age groups were non-drug chemicals (52.7%), medicines (35.2%) and biological toxins (12.6%). Pesticides (34.8%), irritant/corrosive substances (27.7%) and volatile hydrocarbons (8.3%) were the most common classes of non-drug chemical exposures. Cholinesterase inhibitors (8.8%), anticoagulant rodenticides (7.1%) and pyrethroids (5.0%) were the most commonly ingested non-drug chemicals. Aldicarb and amitraz poisoning were identified as toxicovigilance targets. Analgesics (26.1%) were the most common class of medicine-related exposure, and paracetamol (15.8%), benzodiazepines (9.2%) and antihistamines (5.2%) were the most common medicine-related exposures. CONCLUSION: The study provided information on evolving trends and identified toxicovigilance targets and the need for continuing toxicology education programmes.

BACKGROUND: Initial management of acute poisoning in South African (SA) hospitals such as gastric decontamination and use of antidotes has not been evaluated relevant to current international guidelines. OBJECTIVES: The objective of this study was to conduct a toxicovigilance survey of SA hospital admissions to assess the spectrum of acute poisonings, current practices in gastric decontamination, and use of antidotes in the management of acute poisoning. METHODS: A survey was undertaken based on acute poisoning admissions to Tygerberg Academic Hospital (TAH) as well as hospital-based poisoning consultations with the Tygerberg Poison Information Centre (TPIC) over 1 year to investigate trends in admissions and the initial management of hospital admissions for acute poisoning. TAH admission details and TPIC consultation forms for hospital-based cases were analysed for patient demographics, causes of poisoning, gastric decontamination measures and use of antidotes. RESULTS: There were 662 admissions to TAH and 2 459 hospital-based TPIC consultations. Paracetamol and cholinesterase inhibitors were the most common exposures in both studies. Gastric decontamination measures were employed at TAH in 47.7% of cases and in 5.3% of hospital cases reported to the TPIC. Of these, 67.4% in the TAH study and 26.1% in the TPIC study did not comply with international guidelines. N-acetylcysteine was administered inappropriately in 22.1% of the paracetamol poisoning cases at TAH and in 1.6% in the TPIC study. Atropine was administered unnecessarily in 12 of 30 TPIC cases. CONCLUSION: This study has identified the need for directed training on gastric decontamination measures and use of antidotes and, combined with the previous study, has identified national trends in poisoning.

Foram examinados 32 espécimes de Columbina picui (rolinha-picui), sendo que a coleta de artrópodes foi realizada por meio de lavagem da superfície externa do corpo e da cavidade nasal. As espécies da ordem Phthiraptera encontradas e suas respectivas prevalências, abundância média e intensidade média foram: Columbicola passerinae (84,4%; 10,3; 12,2), Hohorstiella passerinae (21,9%; 0,7; 3,1) e Physconelloides eurysema (3,1%; 0,1; 2). Os ácaros Gamasida encontrados nas aves e suas respectivas prevalências, abundância média e intensidade média foram: Pellonyssus marui (31,3%; 1,2; 3,9), Ornithonyssus bursa (15,6%; 0,2; 1,2) e Mesonyssus sp. (6,3%; 0,1; 1). Columbicola passerinae, H. passerinae, P. eurysema, O. bursa, P. marui e Mesonyssus sp. são relatados pela primeira vez parasitando C. picui no Brasil. Exceto O. bursa, as demais espécies são relatadas pela primera vez no estado do Rio Grande do Sul, Brasil.

Thirty-two specimens of Columbina picui (picui ground-dove) were examined, and a collection of arthropods was made by washing the external surface of the body and the nasal cavity. The species in the order Phthiraptera found and their respective prevalences, mean abundance and mean intensity were: Columbicola passerinae (84.4%; 10.3; 12.2), Hohorstiella passerinae (21.9%; 0.7; 3.1) and Physconelloides eurysema (3.1%; 0.1; 2). The gamasid mites found in the birds and their respective prevalences, mean abundance and mean intensity were: Pellonyssus marui (31.3%; 1.2; 3.9), Ornithonyssus bursa (15.6%; 0.2. ;1.2) and Mesonyssus sp. (6.3%; 0.1; 1). Columbicola passerinae, H. passerinae, P. eurysema, O. bursa, P. marui and Mesonyssus sp. were recorded for the first time infecting C. picui in Brazil. Except for O. bursa, the other species are reported for the first time in the state of Rio Grande do Sul, Brazil.

With the aim of identifying the species of nasal mites of Paroaria coronata (red-crested cardinal), the nasal cavity of 40 birds were examined. The nasal mites were identified as Ptilonyssus sairae de Castro and Sternostoma pirangae Pence, with 50% and 7.5% of prevalence, respectively. This is the first record of these mite species parasitizing P. coronata. This report also amplifies the area of occurrence of S. pirangae for Brazil and that of P. sairae for Rio Grande do Sul, Brazil.

Based on previous observational studies on cold extreme events over southern South America, some recent studies suggest a possible relationship between Rossby wave propagation remotely triggered and the occurrence of frost. Using the concept of linear theory of Rossby wave propagation, this paper analyzes the propagation of such waves in two different basic states that correspond to austral winters with maximum and minimum generalized frost frequency of occurrence in the Wet Pampa (central-northwest Argentina). In order to determine the wave trajectories, the ray tracing technique is used in this study. Some theoretical discussion about this technique is also presented. The analysis of the basic state, from a theoretical point of view and based on the calculation of ray tracings, corroborates that remotely excited Rossby waves is the mechanism that favors the maximum occurrence of generalized frosts. The basic state in which the waves propagate is what conditions the places where they are excited. The Rossby waves are excited in determined places of the atmosphere, propagating towards South America along the jet streams that act as wave guides, favoring the generation of generalized frosts. In summary, this paper presents an overview of the ray tracing technique and how it can be used to investigate an important synoptic event, such as frost in a specific region, and its relationship with the propagation of large scale planetary waves.

A partir de los estudios observacionales previos acerca de los eventos extremos fríos en el sudeste de América del Sur, surge la hipótesis la cual plantea que los patrones de gran escala condicionan la frecuencia de ocurrencia de heladas, a través de la propagación de ondas de Rossby excitadas remotamente. Aplicando los conceptos de la teoría lineal de propagación de ondas de Rossby, el objetivo en este artículo es analizar la propagación de tales ondas en dos estados básicos diferentes referidos a los inviernos con una máxima y mínima frecuencia de ocurrencia de heladas generalizadas en la Pampa Húmeda (centro-noreste de Argentina). Basado en los conceptos teóricos acerca de la dispersión de onda y el trazo de trayectorias, se identifican los caminos preferenciales de las ondas de Rossby que alcanzan América del Sur a través de la técnica conocida como trazado de rayos. El análisis del flujo básico desde una perspectiva teórica, basado en los cálculos de las trayectorias, permite comprobar que las ondas de Rossby excitadas en forma remota son el mecanismo que favorece la máxima ocurrencia de heladas generalizadas. Siendo los lugares de excitación de tales ondas condicionados por el estado básico en que se propagan. Ellas son excitadas en lugares determinados de la atmósfera, desplazándose hasta América del Sur a lo largo de los jets que actúan como guías de dichas ondas, propiciando la generación de heladas generalizadas. En suma, este artículo presenta una revisión de la técnica de trazado de rayos y como puede ser usada para investigar la ocurrencia de importantes eventos sinópticos tales como las heladas en una región específica y su relación con la propagación de ondas planetarias de gran escala.

Wireless Local Area Networks (WLAN) have experienced an explosive growth since the introduction of the IEEE802.11 protocol. The fact that it operates on non-licensed frequency bands has given way that a large amount of “hot spots” have been installed by operators that not always have the necessary expertise. In this publication we analyze the problem that arises in a multicell environment where no frequency planning has been carried out. Experimental measurements are performed in such an environment, by controlling parameters like activation of the RTS/CTS mechanism and frequency planning.

Las redes locales inalámbricas de banda ancha han experimentado un desarrollo explosivo con la introducción del protocolo IEEE802.11. El hecho de que éstas operen en una banda no licitada ha permitido que aparezcan numerosos “hot spots”, que no siempre son instalados por personal experto. En este trabajo se analiza el problema que se presenta en un ambiente IEEE802.11b WiFi multicelda en que no se ha tenido el cuidado de planificar la asignación de canales. Se presenta la interferencia medida experimentalmente en un escenario típico multicelda controlando los parámetros de activación del mecanismo RTS/CTS y elección de canales adyacentes.