A molecular approach, polymerase chain reaction–restriction fragment length polymorphism (PCR‐RFL... more A molecular approach, polymerase chain reaction–restriction fragment length polymorphism (PCR‐RFLP), was developed to identify the planktonic larvae of Cynoscion species. Species‐specific mitochondrial DNA markers were developed using three restriction endonucleases (DdeI, HaeIII and HinfI). These markers permitted the accurate discrimination of the five Cynoscion species in the Bay of Panama.
Two new steroids (1 and 2) and the known pregna-1,4,20-trien-3-one (3) have been isolated from th... more Two new steroids (1 and 2) and the known pregna-1,4,20-trien-3-one (3) have been isolated from the Pacific octocoral Carijoa multiflora. Compound 1 possesses a novel spiropregnane-based steroidal skeleton. The photochemical transformation of 3 into 1 allowed the assignment of the absolute configuration at C-10 of 1. The antibacterial activities of compounds 1 and 3 were evaluated against a panel of bacterial strains.
RESUMEN Para poder proyectar el aumento del nivel del mar en Panamá para el final del siglo XXI, ... more RESUMEN Para poder proyectar el aumento del nivel del mar en Panamá para el final del siglo XXI, se procesó información, de más de noventa años de datos mensuales, del nivel del mar registrado diariamente en el Puerto de Balboa entre 1909 y 1998. Se determinaron las tendencias y las regresiones para este período. En adición, se calcularon las tendencias de anomalías mensuales del nivel del mar a intervalos de veinte años, hasta el presente, para el Puerto de Balboa (Pacífico). Los resultados revelan que el aumento del nivel del mar durante el siglo XX fue de aproximadamente 20 cm para el Pacífico (Puerto de Balboa). Mas aún, el análisis estadístico indica que para la costa pacífica de Panamá el aumento de nivel del mar para cada período de veinte años fue cada vez mayor, variando desde 1.70 cm en los primeros veinte años (1909-1929), hasta cerca de 8 cm en los últimos diez años (1988-1999). Como conclusión, el análisis estadístico proyecta el aumento del nivel del mar en la costa pa...
Water clarity and productivity are fundamentally important for the distribution of tropical marin... more Water clarity and productivity are fundamentally important for the distribution of tropical marine organisms. In the Caribbean, changes in nutrient loading that result from rapid development are thought to have caused increased planktonic productivity, reduced water clarity, and reduced reef and seagrass health. Here we analyze chlorophyll a concentration and water clarity from eight years of environmental monitoring in Bocas del Toro, Panama. Chlorophyll a concentrations did not vary significantly among the six sampled sites and showed no significant temporal changes, despite the recent rapid development in the region, accompanied by scant wastewater treatment. In contrast, water clarity increased significantly during the study period. Because chlorophyll a does not vary closely with water clarity, Secchi depths are likely to reflect changes in suspended particulate matter rather than in phytoplankton biomass. Secchi depths decreased with rainfall and wind speed but increased with ...
The evolution of the marine communities along the Pacific coast of Central America, may have chan... more The evolution of the marine communities along the Pacific coast of Central America, may have changed in response to the formation of the Isthmus of Panama. To evaluate the effect of the Aseismic Cocos Ridge (DAC) subduction on the marine benthic communities, we reconstructed benthic assemblages from Neogene fossiliferous formations in Burica and Nicoya peninsulas of Panama and Costa Rica. Paleoecological and paleoenvironmental conditions were reconstructed by comparing community structure from bulk fossil samples with dredge collections from modern Tropical American seas, using principal component analysis. Our results indicate that during the early Pliocene, before the closing of the Isthmus, some oceanic islands existed with moderate upwelling in the Burica region. After the closure, during the late Pliocene and early Pleistocene the collision of the DAC caused an uplift of the seafloor, where water depth of 2 300m became shallow waters of less than 40m depth. Meanwhile, upwelling...
En un estudio sobre la abundancia y la diversidad de los peces estuarinos en el Caribe de Panama,... more En un estudio sobre la abundancia y la diversidad de los peces estuarinos en el Caribe de Panama, entre mayo y diciembre de 1977 , coincidiendo con la estacion lluviosa, se colecto veintiseis especies. Las mas abundantes fueron juveniles de Ulaema lefroyi y Mugil trichodon (31% y 28% de la captura total). Se encontro una diversidad baja de especies y valores maximos de H’ entre 0,81 y casi 0,90. El estudio del efecto de la salinidad, temperatura y precipitacion sobre la poblacion de peces indica que probablemente solo la temperatura tiene algun efecto en la diversidad, mientras que el tamano de los especimenes de algunas especies y la abundancia de otras mostraron correlacion con algunos de estos parametros.
A molecular approach, polymerase chain reaction–restriction fragment length polymorphism (PCR‐RFL... more A molecular approach, polymerase chain reaction–restriction fragment length polymorphism (PCR‐RFLP), was developed to identify the planktonic larvae of Cynoscion species. Species‐specific mitochondrial DNA markers were developed using three restriction endonucleases (DdeI, HaeIII and HinfI). These markers permitted the accurate discrimination of the five Cynoscion species in the Bay of Panama.
Two new steroids (1 and 2) and the known pregna-1,4,20-trien-3-one (3) have been isolated from th... more Two new steroids (1 and 2) and the known pregna-1,4,20-trien-3-one (3) have been isolated from the Pacific octocoral Carijoa multiflora. Compound 1 possesses a novel spiropregnane-based steroidal skeleton. The photochemical transformation of 3 into 1 allowed the assignment of the absolute configuration at C-10 of 1. The antibacterial activities of compounds 1 and 3 were evaluated against a panel of bacterial strains.
RESUMEN Para poder proyectar el aumento del nivel del mar en Panamá para el final del siglo XXI, ... more RESUMEN Para poder proyectar el aumento del nivel del mar en Panamá para el final del siglo XXI, se procesó información, de más de noventa años de datos mensuales, del nivel del mar registrado diariamente en el Puerto de Balboa entre 1909 y 1998. Se determinaron las tendencias y las regresiones para este período. En adición, se calcularon las tendencias de anomalías mensuales del nivel del mar a intervalos de veinte años, hasta el presente, para el Puerto de Balboa (Pacífico). Los resultados revelan que el aumento del nivel del mar durante el siglo XX fue de aproximadamente 20 cm para el Pacífico (Puerto de Balboa). Mas aún, el análisis estadístico indica que para la costa pacífica de Panamá el aumento de nivel del mar para cada período de veinte años fue cada vez mayor, variando desde 1.70 cm en los primeros veinte años (1909-1929), hasta cerca de 8 cm en los últimos diez años (1988-1999). Como conclusión, el análisis estadístico proyecta el aumento del nivel del mar en la costa pa...
Water clarity and productivity are fundamentally important for the distribution of tropical marin... more Water clarity and productivity are fundamentally important for the distribution of tropical marine organisms. In the Caribbean, changes in nutrient loading that result from rapid development are thought to have caused increased planktonic productivity, reduced water clarity, and reduced reef and seagrass health. Here we analyze chlorophyll a concentration and water clarity from eight years of environmental monitoring in Bocas del Toro, Panama. Chlorophyll a concentrations did not vary significantly among the six sampled sites and showed no significant temporal changes, despite the recent rapid development in the region, accompanied by scant wastewater treatment. In contrast, water clarity increased significantly during the study period. Because chlorophyll a does not vary closely with water clarity, Secchi depths are likely to reflect changes in suspended particulate matter rather than in phytoplankton biomass. Secchi depths decreased with rainfall and wind speed but increased with ...
The evolution of the marine communities along the Pacific coast of Central America, may have chan... more The evolution of the marine communities along the Pacific coast of Central America, may have changed in response to the formation of the Isthmus of Panama. To evaluate the effect of the Aseismic Cocos Ridge (DAC) subduction on the marine benthic communities, we reconstructed benthic assemblages from Neogene fossiliferous formations in Burica and Nicoya peninsulas of Panama and Costa Rica. Paleoecological and paleoenvironmental conditions were reconstructed by comparing community structure from bulk fossil samples with dredge collections from modern Tropical American seas, using principal component analysis. Our results indicate that during the early Pliocene, before the closing of the Isthmus, some oceanic islands existed with moderate upwelling in the Burica region. After the closure, during the late Pliocene and early Pleistocene the collision of the DAC caused an uplift of the seafloor, where water depth of 2 300m became shallow waters of less than 40m depth. Meanwhile, upwelling...
En un estudio sobre la abundancia y la diversidad de los peces estuarinos en el Caribe de Panama,... more En un estudio sobre la abundancia y la diversidad de los peces estuarinos en el Caribe de Panama, entre mayo y diciembre de 1977 , coincidiendo con la estacion lluviosa, se colecto veintiseis especies. Las mas abundantes fueron juveniles de Ulaema lefroyi y Mugil trichodon (31% y 28% de la captura total). Se encontro una diversidad baja de especies y valores maximos de H’ entre 0,81 y casi 0,90. El estudio del efecto de la salinidad, temperatura y precipitacion sobre la poblacion de peces indica que probablemente solo la temperatura tiene algun efecto en la diversidad, mientras que el tamano de los especimenes de algunas especies y la abundancia de otras mostraron correlacion con algunos de estos parametros.
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