Artículos científicos

URI permanente para esta colecciónhttp://10.0.96.45:4000/handle/11056/14837

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Biological Activity of Extracts of Trichilia Species and the Limonoid Hirtin Against Lepidopteran Larvae
(Elsevier Science Ltd, 1994) Xie, Y. S.; Isman, M. B.; Gunning, P.; Mackinnon, S.; Arnason, J. T.; Taylor, D. R.; Sánchez. V, P.; Hasbun, C; Towers, G. H. N.
Crude extracts of several Trichilia species (Meliaceae) were evaluated for their behavioral and physiological effects on the polyphagous lepidopterans Peridroma saucia and Spodoptera litura. A majority of extracts of nine Trichilia species, collected primarily from Costa Rica, significantly deter larval growth of P. saucia. Extracts of wood and bark are generally more active than those of foliage. Effects of various tissue extracts from T. connaroides on P. saucia and S. litura were comparatively studied. Extracts of bark, the most active tissue compared to those of wood, seed, exocarp and leaf, reduced larval growth of P. saucia and S. litura by 50% at dietary concentrations of 29.1 and 185.1 ppm, respectively. The limonoid hirtin, a constituent of Trichilia hirta, significantly inhibited larval growth of P. saucia in a dose-dependent manner, with a dietary EC50 (effective concentration to inhibit growth by 50% relative to controls) of 13.0 ppm. Hirtin and various extracts from T. connaroides significantly reduced larval growth and consumption rates, as well as dietary utilization, indicating that these substances possess both behavioral effects and post-ingestive toxicity.
Chemical characterization and source apportionment of PM10 and PM2.5 in the metropolitan area of Costa Rica, Central America
(Universidad Nacional de Costa Rica, 2013-02-28) Herrera, M. J.; Rodriguez, R. S.; Rojas-Marin, J. F.; Campos, R. A.; Blanco, J. S.; Cárdenas, G. B; Gibson, B. D.
PM10 and PM2.5 levels, concentrations of major ionic components, trace elements, and organic and elemental carbon were evaluated from samples collected in 4 sites (industrial, commercial and residential zones) located in the metropolitan area of Costa Rica. The annual mean PM levels were higher in high traffic–commercial (HE–01) and industrial (BE–02) sites, 55 μg m–3 and 52 μg m–3 for PM10 and 37 μg m–3 and 36 μg m–3 for PM2 5, respectively. The major components of PM25 were organic matter (OM) and elemental carbon (EC) (44.5–69.9%), and secondary ions (16.1–27.2%), whereas the major components of PM10 were OM+EC (32.7–59.4%), crustal material (23.5–35.6%) and secondary ions (11.4–26.9%). For the most of the sampling sites, PM10 and PM2.5 concentrations were lower during the dry season and increased gradually in the rainy season due to wind patterns. PMF model identified 8 principle sources for PM10 and PM2.5 in the industrial site (crustal, secondary sulfate, secondary nitrate, secondary organic, traffic, sea–salt aerosols, industrial and oil combustion), 6 and 5 sources in commercial and residential sites, respectively. The source contributions showed a clear seasonal pattern for all the sites.
Chemical composition of bulk precipitation in the metropolitan area of Costa Rica, Central America
(Universidad Nacional de Costa Rica, 2009-05-04) Herrera, M. J.; Rodríguez, R. S.; Báez, A. P.
Tracemetals and inorganic ionswere measured in bulk precipitation sampled at eleven sites in the metropolitan area of Costa Rica. The ions were analyzed by ion chromatography, and the trace metals by atomic absorption spectrometer with a graphite furnace attachment. The results indicated that Na+ and SO4 2− were the most abundant ions, and of the metals, that Al and Fe had the highest concentrations. Spearman's correlation applied to all data showed a high correlation among SO4 2−, NO3− and NH4+, indicating a common anthropogenic origin. In addition, the correlation found between Na+, K+ and Cl−indicated a sea aerosol contribution. High positive correlations between tracemetalswere found for Al–Mn, Ni–Mn, Ni–Al, Cu–Ni, Pb–Cu, Pb–Ni and Pb–Mn.
Desarrollo larval de cichlasoma sp (pisces : cichlidae) cultivados en laboratorio
(Universidad Nacional de Costa Rica, 1988-09-29) Murillo Sánchez, Roger E.
Se describe el desarrollo embrionario y larvario de Cichlasoma sp. tras la fecundación natural de los huevos. Los huevos se obtuvieron de adultos capturados en la Hacienda Santiago, Heredia, Costa Rica. Se mantuvieron en acuarios a 24,5 ± 10,2 °C, 6,4 ppm de O₂ y un fotoperiodo de 12:12 horas. Los huevos son oblongos, de 2,1 mm de longitud y 1,6 mm de ancho. La eclosión ocurre entre las 48 y 52 horas posteriores a la fecundación. Al eclosionar, las larvas miden 4,6 ± 0,1 mm de longitud. El alimento se consume al noveno día después de la eclosión; la alimentación comienza al séptimo día. La fase juvenil comienza con una longitud de 15,5 ± 0,6 mm. La secuencia de desarrollo de las aletas es: pectorales, caudal, anal y pélvicas.
FRUTA DORADA (VIROLA KOSCHNYI WARB.) UNA ESPECIE PROMISORIA PARA LA REFORESTACION EN EL BOSQUE HUMEDO Y MUY HUMEDO TROPICAL
(Universidad Nacional de Costa Rica, 1990-04-30) Eladio, Chaves S; Rodríguez, Johnny; González, Eugenio
We present forestry experiences on the establishment and management of Virola koschyni Warb (Myristicaceae), a tree species from the tropical wet forest. In the nursery, plants were successfully produced by keeping soil brick and pruning the roots. Data from permanent thinning and yield plots showed that after six years, Virola koschyni reached an average 13.3 cm of DBH and 10.5 m of height. In addition, we include ecological and silvicultural information on this little known species.
Heartwood, sapwood and bark contents of bombacopsis quinata in Costa Rica
(Instituto de Investigación Forestal de Malasia, 2004-07) Pérez, D.; Kanninen, M.; Matamoros, F.; Fonseca, W.; Chaves, E.
The Costa Rican government has promoted the establishment of high yielding plantations, expecting to produce high quality timber. Nowadays the management of some species have been uncertain, since wood quality and yield are becoming lower than expected. Heartwood content is a determinant characteristic for Bombacopsis quinata, a widely appreciated species in the country. The aim of this study was to evaluate the heartwood, sapwood and bark content of young and advanced aged B. quinata trees. The research was based on the hypothesis that heartwood content increases with increasing age. By means of stem analysis, the heartwood, sapwood, and bark volume was measured on trees of different ages (10 to 27 years). The highest heartwood proportion found in B. quinata was 13.6%, and the lowest 0.1%. The sapwood ranged between 70.0 and 87.2% while the bark, from 9.4 to 23% of the total stem volume. No clear differences in heartwood content could be observed between trees of similar age from dry and wet zones. Rotation periods for B. quinata in Costa Rica should be extended to produce high quality timber with increased heartwood content.
NUEVAS ESPECIES DE INGA MILLER (MIMOSACEAE) PARA MESOAMERICA
(Universidad Nacional de Costa Rica, 1990-07-16) Zamora V, Nelson.
A partir de un estudio de las Mimosaceae de Costa Rica, se describen aquí nueve especies de Inga nuevas para la ciencia. Se incluye su distribución y afinidades taxonómicas.
Q’eqchi’ Maya healers’ traditional knowledge in prioritizing conservation of medicinal plants: culturally relative conservation in sustaining traditional holistic health promotion
(Springer Nature, 2009-07-30) Pesek, Todd; Abramiuk, Marc; Fini, Nick; Otarola Rojas, Marco; Collins, Sean; Cal, Víctor; Sánchez Vindas, Pablo; Poveda Álvarez, Luis; Arnason, John T.
This ethnobotanical study in the spirit of transdisciplinarity, and in collaboration with Q’eqchi’ Maya traditional healers, compares traditional Q’eqchi’ Maya ecosystem constructs or environmental zones with scientific ecosystems. To determine which categorization method better accommodates Q’eqchi’ Maya medicinal plant diversity, we analized 26 transects representing 160 medicinal plant occurrences. Our transect array encompasses a representative sampling of Q’eqchi’ Maya medicinal plant repertoire with use values broadly distributed over 17 usage categories. With a cumulative frequency of 2,235 medicinal plants through ecological zones, we conducted one-way ANOVA on the mean number of medicinal plant species identified in transects of the two conceptual schemes being contested. Our analysis reveals the Q’eqchi Maya environmental zones are the most salient. That is, knowledge of the Q’eqchi’ Maya environmental zones improves one’s ability to predict whether there will be a high or low abundance of Q’eqchi’ Maya medicinal plant species in a particular region, whereas knowledge of scientific ecosystems does not accomplish this feat as well. This is a notable finding as it suggests that if indeed Q’eqchi’ Maya medicinal plant diversity is better accounted for by the zones as envisioned by the Q’eqchi’ Maya, then it should be this mode of conceptualization that should be adopted by scientists and conservationists when trying to locate and protect regional Q’eqchi’ Maya medicinal plant diversity. These efforts serve as a model internationally in the conservation of medicinal plant biodiversity supportive of culturally relative holistic health promotion.
Southern Hemisphere Additional Ozonesondes (SHADOZ) ozone climatology (2005–2009): Tropospheric and tropical tropopause layer (TTL) profiles with comparisons to OMI-based ozone products
(Universidad Nacional de Costa Rica, 2012-12-01) Thompson, Anne M.; Miller, Sonya K.; Tilmes Simone; Kollonige, Debra W.; Witte, Jacquelyn C.; Oltmans, Samuel J.; Johnson, Bryan J.; Fujiwara, Masatomo; Schmidlin, F. J.; Coetzee, G. J. R.; Komala, Ninong; Maata, Matakite; Mohamad, Maznorizan ; Nguyo, J.; Mutai, C.; Ogino, S-Y; Da Silva, F. Raimundo; Paes Leme, N. M.; Posny, Francoise; Scheele, Rinus; Selkirk, Henry B.; Shiotani, Masato; Stübi, René; Levrant, Gilbert; Calpini, Bertrand; Thouret, Valérie; Tsuruta, Haruo; Valverde Canossa, Jessica; Vömel, Holger; Yonemura, S.; Diaz, Jorge Andrés; Tan Thanh, Nguyen T.; Thuy Ha, Hoang T.
We present a regional and seasonal climatology of SHADOZ ozone profiles in the troposphere and tropical tropopause layer (TTL) based on measurements taken during the first five years of Aura, 2005–2009, when new stations joined the network at Hanoi, Vietnam; Hilo, Hawaii; Alajuela/Heredia, Costa Rica; Cotonou, Benin. In all, 15 stations operated during that period. A west-to-east progression of decreasing convective influence and increasing pollution leads to distinct tropospheric ozone profiles in three regions: (1) western Pacific/eastern Indian Ocean; (2) equatorial Americas (San Cristóbal, Alajuela, Paramaribo); (3) Atlantic and Africa. Comparisons in total ozone column from soundings, the Ozone Monitoring Instrument (OMI, on Aura, 2004-) satellite and ground-based instrumentation are presented. Most stations show better agreement with OMI than they did for EP/TOMS comparisons (1998–2004; Earth-Probe/Total Ozone Mapping Spectrometer), partly due to a revised above-burst ozone climatology. Possible station biases in the stratospheric segment of the ozone measurement noted in the first 7 years of SHADOZ ozone profiles are re-examined. High stratospheric bias observed during the TOMS period appears to persist at one station. Comparisons of SHADOZ tropospheric ozone and the daily Trajectory-enhanced Tropospheric Ozone Residual (TTOR) product (based on OMI/MLS) show that the satellite-derived column amount averages 25% low. Correlations between TTOR and the SHADOZ sondes are quite good (typical r2= 0.5–0.8), however, which may account for why some published residual-based OMI products capture tropospheric interannual variability fairly realistically. On the other hand, no clear explanations emerge for why TTOR-sonde discrepancies vary over a wide range at most SHADOZ sites.
Spatial Distribution and Chemical Composition of Road Dust in Two High-Altitude Latin American Cities
(Universidad Nacional de Costa Rica, 2021-08-28) Vanegas, Sebastián; Trejos, Ericka M.; Aristizábal, Beatriz H.; Pereira, Guilherme M.; Hernández, Julio M.; Herrera-Murillo, Jorge; Ramírez, Omar; Amato, Fulvio; Silva, Luis F. O.; Rojas, Néstor Y.; Zafra, Carlos; Pachón, Jorge E.
Road dust (RD) resuspension is one of the main sources of particulate matter in cities with adverse impacts on air quality, health, and climate. Studies on the variability of the deposited PM10 fraction of RD (RD10) have been limited in Latin America, whereby our understanding of the central factors that control this pollutant remains incomplete. In this study, forty-one RD10 samples were collected in two Andean cities (Bogotá and Manizales) and analyzed for ions, minerals, and trace elements. RD10 levels varied between 1.8–45.7 mg/m2, with an average of 11.8 mg/m2, in Bogotá and between 0.8–26.7 mg/m2, with an average of 5.7 mg/m2, in Manizales. Minerals were the most abundant species in both cities, with a fraction significantly larger in Manizales (38%) than Bogotá (9%). The difference could be explained mainly by the complex topography and the composition of soil derived from volcanic ash in Manizales. The volcanic activity was also associated with SO4􀀀2 and Cl􀀀. Enrichment factors and principal component analysis were conducted to explore potential factors associated to sources of RD10. Elements such as Cu, Pb, Cr, Ni, V, Sb, and Mo were mainly associated with exhaust and non-exhaust traffic emissions.
Sulfate, nitrate and chloride in PM10 in the city of San Jose, Costa Rica: 2004-2006
(Escuela de Ciencias Ambientales, 2009-11-23) Herrera, M. J.; Rojas, M, J. F.; Rodríguez, R. S.; García-Martínez, R.
Se realizó la determinación de los niveles de PM10 en dos sitios de la ciudad de San José (Catedral Metropolitana y Junta de Educación) durante un período de 2.5 años (abril 2004–octubre 2006) obteniendo una mediana de 39 ± 8 y 27 ± 8 µg m–3, respectivamente. En forma adicional, se midieron las concentraciones de SO42–, NO3– y Cl– registrando promedios que no son significativamente diferentes para ambos sitios de medición. Al aplicar el análisis de componentes principales a los datos, se obtuvieron dos factores que explican un 65% del total de la varianza. El factor PC1 incluye a la concentración de Cl– y la velocidad del viento sugiriendo la posible contribución marina de este anión. El factor PC2 muestra una relación entre las concentraciones de SO42–, NO3– y PM10, demostrando su origen antropogénico.
The summertime Boreal forest field measurement intensive (HUMPPA-COPEC-2010): an overview of meteorological and chemical influences
(Copernicus Publications, 2011-10-27) Williams, J; Crowley, J.; Fischer, H.; Harder, H.; Martinez, M.; Petäjä. T.; Rinne, J.; Bäck, Jaana; Boy, M.; Dal Maso, M.; Hakala, J.; Kajos, M.; Keronen, P.; Rantala, P.; Aalto, J.; Aaltonen, H.; Paatero, J.; Vesala, T.; Hakola, H.; Levula, J.; Pohja, J.; Herrmann, F.; Auld, J.; Mesarchaki, E.; Song, W.; Yassaa, M.; Nölscher, A.; Johnson, A. M.; Custer, T.; Sinha, V.; Thieser, J.; Pouvesle, V.; Taraborrelli, D.; Tang, M. J.; Bozem, H.; Hosaynali-Beygi, Z.; Axinte, R.; Oswald, R.; Novelli, A.; Kubistin, D.; Hens, K.; Javed, U.; Trawny, K; Breitenberger, C.; Hidalgo, P.J.; Ebben, C.J.; Geiger, F.M.; Corrigan, A.L.; Russell, M.L.; Ouwersloot, H.G.; Vilà-Guerau de Arellano, J.; Ganzeveld, L.; Vogel, A.; Beck, M.; Bayerle, A.; Kampf, C.J.; Bertelmann, M.; Köllner, F.; Hoffmann, T.; Valverde, J.; González, D.; Riekkola, M.L,; Kulmala, M.; Lelieveld, j.
This paper describes the background, instrumentation, goals, and the regional influences on the HUMPPACOPEC intensive field measurement campaign, conducted at the Boreal forest research station SMEAR II (Station for Measuring Ecosystem-Atmosphere Relation) in HyytiäLä, Finland from 12 July–12 August 2010. The prevailing meteorological conditions during the campaign are examined and contrasted with those of the past six years. Back trajectory analyses show that meteorological conditions at the site in 2010 were characterized by a higher proportion of southerly flow than in the other years studied. As a result the summer of 2010 was anomalously warm and high in ozone making the campaign relevant for the analysis of possible future climates. A comprehensive land use analysis, provided on both 5 and 50 km scales, shows that the main vegetation types surrounding the site on both the regional and local scales are: coniferous forest (Scots pine and/or Norway spruce); mixed forest (Birch and conifers); and woodland scrub (e.g. Willows, Aspen); indicating that the campaign results can be taken as representative of the Boreal forest ecosystem. In addition to the influence of biogenic emissions, the measurement site was occasionally impacted by sources other than vegetation. Specific tracers have been used here to identify the time periods when such sources have impacted the site namely: biomass burning (acetonitrile and CO), urban anthropogenic pollution (pentane and SO2) and the nearby Korkeakoski sawmill (enantiomeric ratio of chiral onoterpenes). None of these sources dominated the study period, allowing the Boreal forest summertime emissions to be assessed and contrasted with various other source signatures.

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