A first approach to assess the impact of bottom trawling over Vulnerable Marine Ecosystems on the High Seas of the Southwest Atlantic

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STRATIGRAPHIC FRAMEWORK FOR ZECHSTEIN CARBONATES ON THE UTSIRA HIGH, NORWEGIAN NORTH SEA

The preserved Zechstein succession on the Utsira High in the NE part of the Norwegian North Sea is 25-100 m thick and is dominated by shelf carbonates. Internal subdivision of the succession is based on the recognition of key surfaces in petrophysical logs and cores, and suggests that the carbonates mainly consist of ZS2 and ZS3 deposits and that younger ZS4 and ZS5 deposits are only locally preserved. The carbonates have undergone early, syn-depositional dolomitization followed by later dolomite recrystallization and calcitization. Calcitization, interpreted as dedolomitization, is restricted to the upper part of the ZS3 carbonate unit and based on U/Pb dating took place during the Triassic, with a later phase of recrystallization linked to mid-Jurassic uplift. Both dedolomitization and dolomite recrystallization relate to fresh-water infiltration with the resetting of δO18 values prior to the Late Jurassic drowning of the Utsira High. The reservoir quality of the carbonates is directly linked to post-depositional meteoric diagenesis, and the best reservoir properties are recorded in intervals dominated by recrystallized dolomites in ZS2 and lower ZS3 carbonates. Dedolomitization significantly reduced porosity in the upper ZS3 carbonates

Cheilostome bryozoan diversity from the southwest Atlantic region: Is Antarctica really isolated?

During the Cenozoic, the break-up of Gondwana was accompanied by a gradual separation of its components and the subsequent establishment of the Antarctic Circumpolar Current, leading to a relative thermal and biogeographic isolation of the Antarctic fauna. However, the zoogeographical affinities of several taxa from South America and Antarctica have been subject to debate, bringing into question the extent of Antarctic isolation.Herewe present newdata on bryozoan species and their spatial distribution in the Argentine Patagonian (AP) region, as well as an analysis of the bryozoological similarities between deep ranges from Argentina and neighboring regions. A total of 108 species of cheilostome bryozoans (378 samples), belonging to 59 genera was found. Five new genera and 36 new species were found in the AP region, while 71 species were reported for the first time from Argentina. The bathymetric ranges of 94 species (87%) were expanded and a high proportion of the identified species (44.4%) also had an Antarctic distribution. The bryozoological affinities found in the current study between the nearest geographical neighbors are in agreement with the hypothesis of the sequential separation of Gondwana during the Cenozoic. Moreover, a high number of shared species, mainly from the slope, were found in this study between the AP region and Antarctica, thus supporting the idea that the Southern Ocean may have been less isolated over geological time than once thought.Spanish Institute of OceanographyPostprin

Optimization of Control Strategies for Non-Domiciliated Triatoma dimidiata, Chagas Disease Vector in the Yucatán Peninsula, Mexico

Chagas disease is the most important vector-borne disease in Latin America. Residual insecticide spraying has been used successfully for the elimination of domestic vectors in many regions. However, some vectors of non-domestic origin are able to invade houses, and they are now a key challenge for further disease control. We developed a mathematical model to predict the temporal variations in abundance of non-domiciliated vectors inside houses, based on triatomine demographic parameters. The reliability of the predictions was demonstrated by comparing these with different sets of insect collection data from the Yucatan peninsula, Mexico. We then simulated vector control strategies based on insecticide spraying, insect, screens and bednets to evaluate their efficacy at reducing triatomine abundance in the houses. An optimum reduction in bug abundance by at least 80% could be obtained by insecticide application only when doses of at least 50 mg/m2 were applied every year within a two-month period matching the house invasion season by bugs. Alternatively, the use of insect screens consistently reduced bug abundance in the houses and offers a sustainable alternative. Such screens may be part of novel interventions for the integrated control of various vector-borne diseases

Eco-bio-social determinants for house infestation by non-domiciliated Triatoma dimidiata in the Yucatan peninsula, Mexico

Background Chagas disease is a vector-borne disease of major importance in the Americas. Disease prevention is mostly limited to vector control. Integrated interventions targeting ecological, biological and social determinants of vector-borne diseases are increasingly used for improved control. Methodology/principal findings We investigated key factors associated with transient house infestation by T. dimidiata in rural villages in Yucatan, Mexico, using a mixed modeling approach based on initial null-hypothesis testing followed by multimodel inference and averaging on data from 308 houses from three villages. We found that the presence of dogs, chickens and potential refuges, such as rock piles, in the peridomicile as well as the proximity of houses to vegetation at the periphery of the village and to public light sources are major risk factors for infestation. These factors explain most of the intra-village variations in infestation. Conclusions/significance These results underline a process of infestation distinct from that of domiciliated triatomines and may be used for risk stratification of houses for both vector surveillance and control. Combined integrated vector interventions, informed by an Ecohealth perspective, should aim at targeting several of these factors to effectively reduce infestation and provide sustainable vector control

Characterization of the Dispersal of Non-Domiciliated Triatoma dimidiata through the Selection of Spatially Explicit Models

Chagas disease is one of the most important neglected diseases in Latin America. Although insecticides have been successfully sprayed to control domiciliated vector populations, this strategy has proven to be ineffective in areas where non-domiciliated vectors immigrating from peridomestic or sylvatic ecotopes can (re-)infest houses. The development of strategies for the control of non-domiciliated vectors has thus been identified by the World Health Organization as a major challenge. Such development primarily requires a description of the spatio-temporal dynamics of infestation by these vectors, and a good understanding of their dispersal. We combined for the first time extensive spatio-temporal data sets describing house infestation dynamics by Triatoma dimidiata inside one village, and spatially explicit population dynamics models. The models fitted and predicted remarkably the observed infestation dynamics. They thus provided both key insights into the dispersal of T. dimidiata in this area, and a suitable mathematical background to evaluate the efficacy of various control strategies. Interestingly, the observed and modelled patterns of infestation suggest that interventions could focus on the periphery of the village, where there is the highest risk of transmission. Such spatial optimization may allow for reducing the cost of control, compensating for repeated interventions necessary for non-domiciliated vectors

Single Dose Novel Salmonella Vaccine Enhances Resistance against Visceralizing L. major and L. donovani Infection in Susceptible BALB/c Mice

Visceral leishmaniasis is a major neglected tropical disease, with an estimated 500,000 new cases and more than 50,000 deaths attributable to this disease every year. Drug therapy is available but costly and resistance against several drug classes has evolved. Despite all efforts, no commercial, let alone affordable, vaccine is available to date. Thus, the development of cost effective, needle-independent vaccines is a high priority. Here, we have continued efforts to develop live vaccine carriers based on recombinant Salmonella. We used an in silico approach to select novel Leishmania parasite antigens from proteomic data sets, with selection criteria based on protein abundance, conservation across Leishmania species and low homology to host species. Five chosen antigens were differentially expressed on the surface or in the cytosol of Salmonella typhimurium SL3261. A two-step procedure was developed to select optimal Salmonella vaccine strains for each antigen, based on bacterial fitness and antigen expression levels. We show that vaccine strains of Salmonella expressing the novel Leishmania antigens LinJ08.1190 and LinJ23.0410 significantly reduced visceralisation of L. major and enhanced systemic resistance against L. donovani in susceptible BALB/c mice. The results show that Salmonella are valid vaccine carriers for inducing resistance against visceral leishmaniasis but that their use may not be suitable for all antigens

Human resources: the Cinderella of health sector reform in Latin America

Human resources are the most important assets of any health system, and health workforce problems have for decades limited the efficiency and quality of Latin America health systems. World Bank-led reforms aimed at increasing equity, efficiency, quality of care and user satisfaction did not attempt to resolve the human resources problems that had been identified in multiple health sector assessments. However, the two most important reform policies – decentralization and privatization – have had a negative impact on the conditions of employment and prompted opposition from organized professionals and unions. In several countries of the region, the workforce became the most important obstacle to successful reform. This article is based on fieldwork and a review of the literature. It discusses the reasons that led health workers to oppose reform; the institutional and legal constraints to implementing reform as originally designed; the mismatch between the types of personnel needed for reform and the availability of professionals; the deficiencies of the reform implementation process; and the regulatory weaknesses of the region. The discussion presents workforce strategies that the reforms could have included to achieve the intended goals, and the need to take into account the values and political realities of the countries. The authors suggest that autochthonous solutions are more likely to succeed than solutions imported from the outside

Estudio de los Ecosistemas Marinos Vulnerables en aguas internacionales del Atlántico Sudoccidental

En este libro, basado en la mejor información científica disponible hasta la fecha, se presentan los resultados y conclusiones de una serie de trece campañas de investigación multidisciplinar realizadas entre octubre de 2007 y abril de 2010 por los componentes del Grupo ATLANTIS a bordo del B/O MIGUEL OLIVER, propiedad de la Secretaría General de Pesca (SGP). El estudio surge a raíz de la solicitud por parte de la SGP (anteriormente denominada Secretaría General del Mar) al Instituto Español de Oceanografía (IEO), para la realización de una serie de campañas de investigación multidisciplinar en aguas internacionales del Atlántico Sudoccidental, dirigidas al estudio de los Ecosistemas Marinos Vulnerables (EMVs) y de las posibles interacciones con las actividades pesqueras. El objetivo final de dichas campañas era el estudio y la identificación cuantitativa, cualitativa y geográfica de los EMVs y de los grupos taxonómicos de organismos sensibles que pudieran existir en la zona de estudio, incluyendo la propuesta de posibles zonas marinas a proteger, para una explotación sostenible de los recursos pesqueros en el ámbito del respeto a los EMVs. Los resultados que se presentan en este libro comprenden los obtenidos a través de los trabajos de geología, geomorfología, bentos, pesca, oceanografía física y análisis de contaminantes en la zona de aguas internacionales del Atlántico Sudoccidental comprendida entre los paralelos 42º y 48ºS, y la isobata de los 1500 m de profundidad (Figura 2.2). Entre estos resultados se incluye el cartografiado y una batimetría detallada de la zona, la descripción del substrato geológico y de los aspectos bentónicos, el análisis de la distribución y abundancia de las especies de mayor interés comercial, la huella de la pesquería, la identificación y descripción preliminar de los EMVs, y la propuesta de Zonas de Protección, basada en criterios Geológicos, Geomorfológicos y Biológicos. Toda esta información ha sido incorporada para su tratamiento en una plataforma SIG (Sistema de Información Geográfica) y los resultados obtenidos y presentados en este libro vienen acompañados de abundante información gráfica, como imágenes batimétricas en 3D, fotografías de bentos (infauna y epifauna), imágenes tomadas con un ROV (Remotely Operated Vehicle) y con una cámara digital submarina, así como una serie de mapas de distribución, capturas y densidad de las principales especies de interés pesquero. Se incluye también un mapa con la huella de la pesquería (1989-2010) que permita observar la incidencia de las Zonas de Protección propuestas en el área en la que faena habitualmente la flota española de arrastre de fondo. Como información adicional a la obtenida en las trece campañas de investigación, también se ha utilizado la base de datos creada con la información recogida por el Programa de Observadores del IEO entre los años 1989-2010, referente a datos comerciales, biológicos, oceanográficos y físicos (batimetría, temperatura superficial del mar y temperatura del fondo). Entre octubre de 2007 y abril de 2010 se han realizado un total de trece campañas de investigación multidisciplinar, que se han concretado en los siguientes trabajos: • 347 días efectivos de mar • Prospección de una superficie total de 59.105 km2 • Realización de un total de 91.905 km de perfiles geofísicos • 102 muestreos con draga de roca • 209 muestreos con draga box corer • 519 estaciones de CTD • 413 lances de pesca • 413 muestras de sedimentos con el colector de red • Recogida de varios miles de lotes de muestras de bentos que representan varios centenares de miles de especímenes y/o colonias • Realización de miles de fotografías de especies bentónicas, centenares de imágenes digitales de alta resolución y decenas de horas de vídeo realizadas con el ROV del barco Entre los principales resultados de los trabajos de investigación multidisciplinar presentados en este libro hay que destacar la identificación, descripción y delimitación de los EMVs, siguiendo criterios biológicos, geológicos y mixtos; la identificación de los principales grupos bentónicos indicadores de EMVs; la determinación de los valores que representan una captura significativa de los distintos taxones considerados como vulnerables según criterios de la ONU y OSPAR, y finalmente, la propuesta de áreas marinas que deberían ser consideradas como candidatas a ser protegidas. En total se proponen nueve polígonos de diferente superficie para su valoración como zonas de protección (Figura 7.5) y se hace referencia a la incidencia que el cierre de dichas zonas podría tener sobre la actividad de la flota, es decir, el grado de solapamiento entre las zonas de protección y la huella de la pesquería (Figura 7.6). Todos estos resultados se presentan acompañados de abundantes gráficas, figuras y mapas.Instituto Español de OceanografíaVersión del edito