Facultad de Ciencias de la Tierra y el Mar
URI permanente para esta comunidadhttp://10.0.96.45:4000/handle/11056/14052
La Facultad de Ciencias de la Tierra y Mar (FCTM) de la Universidad Nacional (UNA), se crea en el año 1973 y desde sus inicios se ha caracterizado por su compromiso con los principios y valores que sustentan la Universidad Necesaria; la cual en lo fundamental se caracteriza por la búsqueda de nuevos espacios que le permitan seguir aportando a la sociedad profesionales y productos de la investigación, extensión y servicios que contribuyan a la mejora en la calidad de vida de la población costarricense y sus relaciones con la naturaleza.
Decana: Grace Wong Reyes, Ph.D, correo electrónico: grace.wong.reyes@una.cr
Contacto:
Página web: www.tierraymar.una.ac.cr
Correo: fctm@una.cr
Teléfono: (506) 2277-3226 / (506) 2277-3280
Biblioteca Especializada Facultad de Ciencias de la Tierra y el Mar:
Página web: www.bctm.una.ac.cr
Correo: bctm@una.cr
Teléfono: 2562-6490 / 2562-6491
Facebook: @BibliotecaTierrayMar
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Ítem 9th Latin American Pesticide Residue Workshop (LAPRW 2023) Food and Enviroment, May 18-20, 2021(Thermo Fisher Scientific, 2021) Universidad Nacional del Litoral (Panamá)Thermo Fisher Scientific patrocina el 9º Latin American Pesticide Residue Workshop (LAPRW), que se realizará del 21 al 24 de mayo de 2023 en el Sheraton Grand Hotel Panamá. Visítenos en el stand #P2 y descubra nuestras soluciones para el análisis de pesticidas, enfocadas en aumentar la productividad y la confiabilidad de los resultados. El evento abordará temas como métodos analíticos, control de calidad, regulación y análisis de riesgos.Ítem A biogeochemical comparison of three representative lakes of Costa Rica(INLAND WATERS (Taylor and Francis), 2025-06-09) Esquivel-Hernández, Germain; Sánchez-Gutiérrez, Rolando; Arias, M.; Ugalde-Salazar, Rocío; Echeverría- Sáenz, SilviaLakes are widely distributed across Costa Rica, from coasts to the highest elevation regions and located in the main terrestrial biomes, yet updated biogeochemical information about the main types of lakes is still lacking. We present comparative biogeochemistry (water chemistry, stable isotopes, and picoplankton) for a coastal lake (Lake Madre de Dios), a volcanic lake (Lake Barva), and a glacial lake (Lake Ditkevi). Sampling was conducted between February and November 2022, including dry and rainy seasonal conditions. Hydrological and chemical conditions were evaluated using water and carbon stable isotopes, dissolved organic matter, major ions, and microbiota analysis. Isotopic data on water (δ2H and δ18O) and dissolved inorganic carbon (δ13CDIC) confirmed lower evaporative losses for the maar and tarn lakes and productivity response to precipitation inputs. Excitation/emission matrices confirmed the prevalence of fulvic and humic acids in the coastal and glacial lakes, mainly aromatic proteins and soluble microbial byproducts in the volcanic lake. Picophytoplankton (PPP, ∼0.2–10 μm) was mainly represented by phycocyanin-rich picocyanobacteria in the 3 lakes, but maar and tarn lakes had greater representation of phycoerythrin-rich picocyanobacteria. We confirmed fluctuations in PPP cell abundance in the lakes was lower than in comparable temperate lakes. For other eutrophic lakes, abundance of picocyanobacteria dominated over picoeukaryotic algae. This work aimed to promote an ecosystem approach to study the biogeochemical functioning of tropical lakes using a combination of chemical, hydrological, and biological data and to provide baseline information for future studies (e.g., climate change and pollution impacts) on tropical lakes of Costa Rica.Ítem A botanical extract of Souroubea sympetala and its active principle, betulinic acid, attenuate the cortisol response to a stressor in rainbow trout, Oncorhynchus mykiss(Elsevier, 2016-09-28) Mullally, Martha; Mimeault, Caroline; Otárola Rojas, Marco Antonio; Sanchez Vindas, Pablo; Garcia, Mario; Poveda Alvarez, Luis; Moon, Thomas W.; Gilmour, Kathleen M.; Trudeau, Vance; Arnason, JohnThe capacity of the traditional anxiolytic plant, Souroubea sympetala, and its bioactive principle, betulinic acid (BA), to lower cortisol levels in rainbow trout, Oncorhynchus mykiss, was investigated. Effects at the level of the cortisol-producing interrenal cells were investigated using an in vitro head kidney preparation. Head kidney tissue incubated with S. sympetala extract or BA produced significantly less cortisol in response to adrenocorticotropic hormone (ACTH) than cells incubated with ACTH alone; a 50% reduction in the cortisol response was predicted to occur at 43 μg mL− 1 extract or 71 μg mL− 1 BA. To investigate whether effects on interrenal cell cortisol production translated into effects at the whole-animal level, the plasma cortisol response to an acute stressor, confinement in a net, was assessed. Fish fed a commercial trout pellet diet supplemented with 1 mg kg− 1 fish BA for six days exhibited a significantly lower plasma cortisol response to the acute stressor than fish fed the unsupplemented diet. Collectively, these results demonstrate that S. sympetala and BA act on the interrenal cells of the hypothalamic-pituitary-interrenal (HPI) axis in rainbow trout to significantly attenuate the cortisol response to an acute stressor. These findings suggest that BA is of potential use in mitigating effects of exposure to the stressors commonly encountered in an aquaculture setting. Statement of relevance • Souroubea sympetala extract and betulinic acid reduced ACTH-stimulated cortisol production by head kidney tissue in vitro, with little or no evidence of cytotoxicity.• The cortisol response to an acute stressor was attenuated in rainbow trout fed a commercial diet supplemented with betulinic acid.• The cortisol-reducing properties of the S. sympetala extract and betulinic acid may be useful in mitigating effects of stress in aquaculture, particularly since, as natural products, they may raise less public concern with respect to human consumption.Ítem A comparison of fruit removal in Ficus colubrinae between birds and Ectophylla alba (Chiroptera: Phyllostomidae) in a Costa Rican rain forest(Taylor and Francis Ltd., 2021-02-02) De la Llata Quiroga, Edna; Ruedas, Luis; Mora, José ManuelEctophylla alba almost exclusively feeds on the fruits of Ficus colubrinae therefore significantly contributing to dispersal of its seeds. The objective of this research was to quantify the fruit removal of F. colubrinae by E. alba and compare it with that of birds in a F. colubrinae tree at the La Selva Biological Station, Costa Rica. We established seven quadrats randomly at different heights of the tree. We took photographs of each quadrat, quantified the fruits in each photograph, and compared the number of fruits removed during periods of high and low activity. The on-site persistence time of birds (9:05 min) was higher than that of E. alba (0.32 s). Birds removed more fruits (46) than E. alba (41). Birds defecated on site more times (13.08 feces per day) than E. alba (7.5 feces per day). Thus, E. alba is a more important seed disperser of F. colubrinae than are birds, because it persisted a short time at the feeding site, and consumed food beyond the individual trees’ canopies. Most importantly, by defecating during flight or away from the fruiting tree, E. alba disperse seeds some distance from the F. colubrinae tree, thereby contributes more effectively toward seed dispersal.Ítem A female of Eudorylaimus sp with two vulvae.(Universidad Nacional, Costa Rica, 2001) Esquivel Hernández, AlejandroA female of Eudorylaimus sp, with two vulvae was found in Tempisque Conservation Area in Costa Rica. Thousands of nematodes have been prepared in Cobb's slides to study nematode diversity in Costa Rica; nevertheless, only one aberrant female has been found. The two vulvae are very close to each other and vaginal sclerotization plates show abnormal formation. There is no linkage between the uterus and the gonoducts and the ovaries are poorly developed. An absence of sperm and eggs suggests that the genital apparatus is not functional. Because identification at the species level teas not achieved, more specimens and studies are neededÍtem A new nesting record for the jabiru in Costa Rica(Waterbird Society, 1998) Villarreal Orias, JohnnyI document the first nesting record of theJabiru (Jabiru mycteria) in "Los Guatuzos" forest floodplain, Alajuela province, Costa Rica. The active nest was located in March 1995 at 10°49'23.70"N and 84°47'23.20"W. The nest was 16m high in a 23m high silk-cotton tree (Ceiba pentandra) and contained three chicks. The zone is not protected and active lumbering is underway.Ítem A Sensitivity Analysis of the Application of Integrated Species Distribution Models to Mobile Species: A Case Study with the Endangered Baird's Tapir(Cambridge University Press, 2019-04-21) Schank, Cody J; Cove, Michael V; Kelly, Marcella J; Nielsen, Clayton K; Farrill, Georgina O; Meyer, Ninon; Jordan, Christopher A; González-Maya, Jose F; Lizcano, Diego J; Moreno, Ricardo; Dobbins, Michael; Montalvo Guadamuz, Víctor Hugo; Cruz Díaz, Juan Carlos; Pozo, Gilberto; de la Torre, J. Antonio; Brenes Mora, Esteban; Wood, Margot A; Gilbert, Jessica; Jetz, Walter; Miller A, JenniferSpecies distribution models (SDMs) are statistical tools used to develop continuous predictions of species occurrence. 'Integrated SDMs' (ISDMs) are an elaboration of this approach with potential advantages that allow for the dual use of opportunistically collected presence-only data and site-occupancy data from planned surveys. These models also account for survey bias and imperfect detection through the use of a hierarchical modelling framework that separately estimates the species-environment response and detection process. This is particularly helpful for conservation applications and predictions for rare species, where data are often limited and prediction errors may have significant management consequences. Despite this potential importance, ISDMs remain largely untested under a variety of scenarios. We performed an exploration of key modelling decisions and assumptions on an ISDM using the endangered Baird's tapir (Tapirus bairdii) as a test species. We found that site area had the strongest effect on the magnitude of population estimates and underlying intensity surface and was driven by estimates of model intercepts. Selecting a site area that accounted for the individual movements of the species within an average home range led to population estimates that coincided with expert estimates. ISDMs that do not account for the individual movements of species will likely lead to less accurate estimates of species intensity (number of individuals per unit area) and thus overall population estimates. This bias could be severe and highly detrimental to conservation actions if uninformed ISDMs are used to estimate global populations of threatened and data-deficient species, particularly those that lack natural history and movement information. However, the ISDM was consistently the most accurate model compared to other approaches, which demonstrates the importance of this new modelling framework and the ability to combine opportunistic data with systematic survey data. Thus, we recommend researchers use ISDMs with conservative movement information when estimating population sizes of rare and data-deficient species. ISDMs could be improved by using a similar parameterization to spatial capture-recapture models that explicitly incorporate animal movement as a model parameter, which would further remove the need for spatial subsampling prior to implementation. © 2019 Foundation for Environmental Conservation.Ítem Altitudinal zonation of montane Quercus forests along two transects in Chirripó National Park, Costa Rica(Springer, 1995-08) Kappelle, Maarten; Van Uffelen, Jan-Gerrit; Cleef, AntoineAbiotic and vegetation data were collected along two altitudinal transects through mature montane Quercus forests on the Pacific and Atlantic slopes of Costa Rica's Chirripó Massif. Between 2000 and 3200 m asl twenty-four 0.05 ha forest plots were selected at altitudinal intervals of 100 m, and eight soil profiles were described at intervals of 200 m. A TWINSPAN classification aided in the determination of eight zonal forest communities on the basis of their floristic composition. They are grouped in two sets of four: (i) the palm-rich lauraceous-fagaceous Lower Montane Mollinedia-Quercus Forests (2000-2600 m asl) and (ii) the bamboo-rich myrsinaceous-fagaceous Upper Montane Schefflera-Quercus Forests (2500-3200 m asl), respectively. Vegetation changes seem correlated with two major climatic gradients: (i) a temperature gradient (altitude), and (ii) a moisture gradient (wet Atlantic vs. moist Pacific slope). Most soils are Andepts, and residual, colluvial or derived from volcanic material. Humus layers are thicker on the wetter Atlantic slope. A total of 431 vascular plant species consisted of 86 pteridophytes, 1 gymnosperm, 296 dicots and 48 monocots. Species richness, canopy height and stem diameter decrease with increasing altitude, while the canopy surface becomes more flattend. A comparison with other studies shows that Chirripó's montane Quercus forests fit within the environmental ranges known from altitudinal zonations elsewhere in the Tropics. © 1995 Kluwer Academic Publishers.Ítem Analysis of the Interactions Between Humans and Crocodiles in Costa Rica(Sociedade Brasileira de Herpetologia, 2020) Porras Murillo, Laura Patricia; Mata Cambronero, ErickThe habitat of crocodiles (Crocodylus acutus) and caimans (Caiman crocodilus) has been subjected to pressure due to human expansion. Habitat reduction, coupled with the simultaneous growth of the crocodile population, increases the number of interactions between crocodiles and humans. There is currently no official and systematized interactions database, but it is necessary to know the magnitude and nature of the interactions and establish management measures. The objective of the work was to systematize and evaluate the interactions between crocodiles and humans in Costa Rica. Historical information was collected from several sources. A total of 99 records, dated between 1990–2017, were found from press reports and the Integrated System for Processing Environmental Complaints of the Ministry of Environment and Energy (SITADA). The Fire Department recorded 123 events in 2017. All Fire Department records corresponded to encounters or sightings. Of the SITADA incident records, 35.4% were non-fatal, 27.3% were fatal, 21.2% were encounters and sightings, and the remaining 16.1% were miscellaneous situations. Most interactions occurred during the day, a fact potentially explained by human behavior of being in bodies of water or on adjacent shoreline while the sun is out. Most interactions occurred in the Central Pacific, followed by the Caribbean and then the South Pacific. The information available is brief but allows to establish management measures. The country needs to create a national database of interactions and to encourage individuals to report their interactions. Further research should continue to analyze the data for trends with the goal of building recommendations to prevent an increase in negative interactions.Ítem Analytical and rheological studies of modified gel dosimeters exposed to X-ray beams(Elsevier Science, 2016-07) Romero, Marcelo Ricardo; Mattea, Facundo; Vedelago, José; Chacón Obando, David M; Valente, Mariana A.; Alvarez, Cecilia; Strumia, Miriam CristinaThe need to know the dose of X-rays to be applied to patients suffering diseases such as cancer requires accurate and stable dosimetric devices. Currently, the use of gelatin-based dosimeters has yielded excellent results but lack adequate thermal stability. In this paper a chemical modification of the gelatin (at concentrations typically used for the preparation of dosimeters) using glutaraldehyde as a cross-linking agent is proposed. Through rheological studies it was found that modified gelatin with glutaraldehyde concentrations between 0.15 and 0.50% w/v shows better thermal stability with an increase in elastic modulus of up to 100 times at 37 °C and convenient reaction times for the preparation of the dosimeters. Subsequently, a mathematical model to easily predict the elastic modulus of materials prepared with different concentrations of gelatin and glutaraldehyde was proposed. The analytical response of modified and unmodified materials was evaluated and no significant alteration of the dosimetric sensitivity was found in the dosimeters (based on itaconic acid and N, N′-methylenebisacrylamide) when an X-ray irradiation dose from 0 to 300 Gy was applied. It was found that the best thermal stability of dosimeters prepared with modified gelatin would decrease the loss of information between the irradiation process and the absorbance reading, thereby improving the stability and linear correlation of data. °C and convenient reaction times for the preparation of the dosimeters. Subsequently, a mathematical model to easily predict the elastic modulus of materials prepared with different concentrations of gelatin and glutaraldehyde was proposed. The analytical response of modified and unmodified materials was evaluated and no significant alteration of the dosimetric sensitivity was found in the dosimeters (based on itaconic acid and N, N′-methylenebisacrylamide) when an X-ray irradiation dose from 0 to 300 Gy was applied. It was found that the best thermal stability of dosimeters prepared with modified gelatin would decrease the loss of information between the irradiation process and the absorbance reading, thereby improving the stability and linear correlation of data. Overall, the results indicated that the dosimeters could be modified as proposed and achieve significant improvements regarding to their thermal stability, without changing significantly the usual preparation process.Ítem Anti-inflammatory and antinociceptive activities of Loasa speciosa in rats and mice(Elsevier, 2003) Badilla Baltodano, Beatriz; Arias, A. Y.; Arias, M.; Mora, G. A.; Poveda Alvarez, LuisIn the range of doses of 250–500 mgykg (given i.p.) the aqueous extract of Loasa speciosa leaves showed an inhibitory effect on leukocyte migration, and a reduction on the pleural exudate, as well as dose-dependent anti-inflammatory and peripheral antinociceptive activities.Ítem Anxiolytic activity and active principles of Piper amalago (Piperaceae), a medicinal plant used by the Q’eqchi’ Maya to treat susto, a culture-bound illness(Elsevier, 2016-06-05) Mullally, M.; Cayer, C.; Muhammad, A.; Walshe-Roussel, B.; Ahmed, F.; Sanchez-Vindas, PE.; Otárola Rojas, Marco Antonio; Merali, Zul; Cal, V.; Durst, Tony; Trudeau, Vance; Arnason, JohnEthnopharmacological relevance The medicinal plant, Piper amalago L. (Piperaceae), is used traditionally by Q'eqchi' Maya healers for the treatment of "susto" a culture-bound syndrome. Previous research suggests that susto symptoms may be a manifestation of anxiety. The objectives were to characterize the effect of ethanolic extract of P. amalago in behavioral assays of anxiety at doses representative of traditional use and to isolate active principles. Materials and methods Rats treated orally with low dose ethanolic extracts of P. amalago leaves (8-75 mg/kg) were tested in several behavioral paradigms including the elevated plus maze (EPM), social interaction (SI), and conditioned emotional response (CER) tests, and compared to diazepam, a positive control. The active anxiolytic principle was isolated by bioassay guided isolation using an in vitro GABAA competitive binding assay. Results Extracts had significant anxiolytic activity in all behavioral tests, with the strongest activity in the SI and the CER paradigms. In an in vitro GABAA competitive binding assay, a 66.5 μg/mL concentration of P. amalago ethanol extract displaced 50% of the GABAA-BZD receptor ligand [3H]-Flunitrazepam. Bioassay-guided fractionation identified a furofuran lignan, a molecule with structural similarity to yangambin, with high affinity for the GABAA-BZD receptor as the principle bioactive. Conclusion The results suggest that the ethnobotanical use of this plant may have a pharmacological basis in its anxiolytic activity, as demonstrated in animal behaviour tests.Ítem Are the ashes from the latest eruptions (2010–2016) at Turrialba volcano (Costa Rica) related to phreatic or phreatomagmatic events?(Elsevier, 2016-09-15) Mele, Daniela; Alvarado Induni, Guillermo E.; Dellino, Pierfrancesco; de Moor, Joost Maarten; Avard, GeoffroyThe initial eruptive episodes of explosive eruptions are classified as phreatic if the amount of juvenile material (scoria, glass, pumice) is null, and the amount of fresh accidental lithics, and hydrothermally altered lithics, is substantial. Phreatic eruptions have been in some cases recognized as precursory events preceding phreatomagmatic and magmatic eruptive phases. Usually, the lithological features of tephra deposits are investigated and sampled in the field. Investigation of ash samples under binocular microscope or by Back-Scattered Electron (BSE) microscope images of polished sections is usually considered sufficient to typify the fragmentation mechanism of the eruption. The opening eruptive phases at Turrialba volcano, together with the formation of newintracraters (i.e. 2010, 2012, 2014) and the enlargement of theWestern Crater (29 October 2014 to present), were classified, in previous papers and internal reports as phreatic. We studied a series of ash samples erupted from 2010 to 2016, with the aim of understanding the fragmentation processes characterizing the vent opening phases.We used SEM+EDS analyses, in addition to field and microscopic investigation. Results showed a composition of accidental lithics of fresh to hydrothermally altered clasts and secondary minerals (82–98%), besides juvenile andesite fragments (2–18%), which leads us to revisit the classification of the initial eruptive phases of Turrialba as phreatomagmatic. Our method allowed the detection of a juvenile component directly involved in an effective magma-water interaction, which was possible only by a scrutinous examination of the glass surface textures by SEM in the range size between 3 and 3.5 phi. We recommend such a type of investigation when the identification of fresh magma in a new eruption is crucial for the preparedness and hazard evaluation at active volcanoes.Ítem Biomass dynamics of Erythrina lanceolata as influenced by shoot-pruning intensity in Costa Rica(Springer, 2003) Berninger, Frank; Salas, EduardoPruning of agroforestry trees, while reducing shade of the crops, usually reduces both biomass production and nitrogen fixation. Short pruning cycles are often not sustainable on the long run, because tree production declines over subsequent pruning cycles. We compared biomass and labile carbohydrate dynamics of Erythrina lanceolata Standley (Papilionaceae) shade trees under total and partial pruning regimes in a vanilla (Vanilla planifolia L.) plantation in South-western Costa Rica. The highest biomass production was measured in the unpruned control, followed by trees with 50% of the leaf pruned every three months, while total pruning every six months resulted in the lowest biomass pruduction. In the more productive treatments, a higher proportion of the production was in branches. Because, the N content of woody branches was high, they were important for nitrogen cycling. In the partial pruning treatment more nitrogen was returned to the soil from litter and woody branches than from pruned leaf. Sugar concentrations were not different between treatments and the dynamics of non-structural carbohydrates (sugar and starch) seems to depend more on plant phenology than pruning treatment. However, the starch concentrations in the total pruning were lower than in the other treatments.Ítem Blown by the wind: the ecology of male courtship display behavior in orchid bees(Ecological Society of America, 2017-02-01) Pokorny, Tamara; Vogler, Ira; Losch, René; Schlütting, Patrick; Juarez, Pedro; Bissantz, Nicolai; Ramirez, Santiago; Eltz, ThomasMany insects rely on chemical signals to transmit precise information on the location, identity, and quality of potential mates. Chemical signals are often broadcasted at sites with physical properties that maximize signal propagation and signal transmission. Male neotropical orchid bees (Euglossini) perch and display on vertical branches and tree trunks in the forest to expose volatile blends (perfumes) that they previously collected from their environment. Previous studies have shown that the chemical composition of perfume blends is highly differentiated even between closely related species. However, variation in behavioral components of perfume exposure and male display remain poorly understood. We conducted a four-year study on orchid bee display sites (8 species) in pacific Costa Rica, using field observations along with chemical analysis and cage experiments to assess display niche partitioning among sympatric species. We evaluated the influence of physical factors (terrain, wind, light) on the distribution of perch sites and on display behavior, and tested a prediction of the sex pheromone-analogue hypothesis, i.e., that displaying males have above-average quantities or qualities of acquired perfumes. Males of different species displayed in the same general area and sometimes in close proximity to each other, but partitioned the display niche by selecting different perch diameters, display heights, and by displaying at different times of the day. Most perch sites were located inside the forest on elevated ground, especially along ridges, where stronger winds may help disperse perfume signals. Furthermore, the angular position of displaying males on perches was narrowly determined by wind direction, with males being positioned on the downwind side of the perch, where they would be most conspicuous to conspecifics approaching on an odor trail. Although our results generally support the hypothesis that perfumes serve as pheromone analogues, we did not find differences in the perfume composition of males caught at display perches and males captured at chemical baits. This suggests that, while chemical communication is an integral part of orchid bee display, male display activity is not determined by the history of, and success in, volatile acquisition. © 2017 by the Ecological Society of AmericaÍtem Camera trapping ocelots: An evaluation of felid attractants(Universidad Nacional, Costa Rica, 2014) Cove, Michael; Spinola, Manuel; Jackson, Victoria; Saenz, JoelOcelots (Leopardus pardalis) and other wild cats are often surveyed using camera traps to identify individuals for density estimation via capture-recapture analyses or estimate occupancy via detection/non-detection analyses. Though attractants are sometimes used in such surveys, there have not been any evaluations of the effectiveness of common visual and olfactory attractants in field settings. As part of a medium and large mammal camera survey in the San Juan – La Selva Biological Corridor, Costa Rica, we integrated camera trap data within an occupancy modelling framework to estimate the effects of hanging compact disks (visual), cologne (olfactory), and sardines in oil (olfactory) on ocelot detection probabilities. Compact disks appeared to have the most information-theoretic model support, whereas cologne received less model support. The use of compact disks in surveys was also less time-consuming and less expensive than the olfactory at tractants. Ocelots are visual hunters and using visual attractants can increase detection probabilities and therefore reduce uncertainty and/or reduce survey effort to obtain robust population or occu pancy estimates, although using cologne might also have similar effects. Depending on logistic constraints, we recommend employing several attractants as the most appropriate way to survey ocelots and other rare felids in the future when detection biases are assumed to be strong, particu larly as part of mammal community surveys.Ítem Caregiving and infants' neurodevelopment in rural Costa Rica: results from the Infants’ Environmental Health Study (ISA)(Elsevier, 2019-06-05) Till, Christine; Dudani, Ameeta; Cordoba, Leonel; Cano, Juan Camilo; Green, Rivka; Menezes-Filho, José A.; Schnaas, Lourdes; Smith, Donald R.; Lindh, Christian; van Wendel de Joode, BernaEarly caregiving is one of the strongest influences on children’s development, and among the most significant modifiable environmental factor. The aim of this study was to explore the association between quality of caregiver-infant interactions and neurodevelopment of infants living in banana-growing communities in rural Costa Rica characterized as having environmental toxic exposures. Home visits were conducted with 94 caregiver- infant dyads from the Infants’ Environmental Health Study (ISA), living within Matina county, Limón province. One-year infant neurodevelopmental outcomes were assessed using the Bayley Scales of Infant and Toddler Development®, Third Edition (Bayley-III). Quality of caregiver-infant interaction was assessed with a standardized observational task: Nursing Child Assessment Satellite Training Teaching scale (NCATS) at around two years of age. Multiple regression analyses examined associations between components of caregiver-infant interactions and neurodevelopmental outcomes, adjusting for mancozeb and manganese exposure and other potential confounders. Compared to NCATS normative data for U.S. Hispanic mothers, 35% of the sample had overall caregiving interaction scores ≤10th percentile cut-off, indicating less than optimal interactions. Higher quality of caregiver-infant interaction was associated with higher expressive communication ability in infants [ß=0.03 (95% CI: 0.01, 0.06)], controlling for pesticide exposure and confounders. Aspects of caregiving such as stimulation and growth-fostering of infants were most strongly associated with language outcomes. Results suggest an association between positive caregiving on language development for infants living in a rural agricultural area in Costa Rica, and highlight aspects of caregiving that could be targeted to improve resilience of these children who live in vulnerable conditions.Ítem Caregiving and infants' neurodevelopment in rural Costa Rica: Results from the Infants’ Environmental Health Study (ISA)(Elsevier, 2019-09) Till, Christine; Dudani, Ameeta; Cordoba, Leonel; Cano, Juan Camilo; Green, Rivka; Menezes-Filho, José; Schnaas, Lourdes; Smith, Donald R.; Lindh, Christian; van Wendel de Joode, BernaEarly caregiving is one of the strongest influences on children's development, and among the most significant modifiable environmental factor. The aim of this study was to explore the association between quality of caregiver-infant interactions and neurodevelopment of infants living in banana-growing communities in rural Costa Rica characterized as having environmental toxic exposures. Home visits were conducted with 94 caregiver-infant dyads from the Infants’ Environmental Health Study (ISA), living within Matina county, Limón province. One-year infant neurodevelopmental outcomes were assessed using the Bayley Scales of Infant and Toddler Development®, Third Edition (Bayley-III). Quality of caregiver-infant interaction was assessed with a standardized observational task: Nursing Child Assessment Satellite Training Teaching scale (NCATS) at around two years of age. Multiple regression analyses examined associations between components of caregiver-infant interactions and neurodevelopmental outcomes, adjusting for mancozeb and manganese exposure and other potential confounders. Compared to NCATS normative data for U.S. Hispanic mothers, 35% of the sample had overall caregiving interaction scores ≤10th percentile cut-off, indicating less than optimal interactions. Higher quality of caregiver-infant interaction was associated with higher expressive communication ability in infants [ß = 0.03 (95% CI: 0.01, 0.06)], controlling for pesticide exposure and confounders. Aspects of caregiving such as stimulation and growth-fostering of infants were most strongly associated with language outcomes. Results suggest an association between positive caregiving on language development for infants living in a rural agricultural area in Costa Rica, and highlight aspects of caregiving that could be targeted to improve resilience of these children who live in vulnerable conditionsÍtem Central nervous system tumours in children in Costa Rica: 1981–96(Blackwell Science, 2002) Reutfors, Johan; Kramárová, Eva; Weiderpass, Elisabete; Monge, Patricia; Wesseling, Catharina; Ahlbom, AndersIncidence rates of malignant central nervous system (CNS) tumours in children in Costa Rica are presented in an international perspective. For the 16-year period 1981–96, a total of 256 CNS tumours were registered in children below age 15 years by the National Tumour Registry of Costa Rica. The age-standardised incidence rate was 15.2 per million person–years, with a male-to-female ratio of 1.4. The median age-standardised incidence rates of selected registries in other Latin American countries were 19.3, in other developing countries 12.0 and in industrialised countries 29.6 per million person–years. The comparatively low incidence rates in Costa Rica were evident in all diagnostic subgroups, most notably in the youngest age group and for tumours in the brain stem. In the Central Valley, where the capital and the only specialised paediatric hospital are situated, the crude incidence rate was 18.1 [95% CI 15.1, 21.1] compared with 10.5 [95% CI 8.3, 12.8] per million person–years in the rest of the country (RR = 1.7, 95% CI 1.3, 2.3). There was no evidence of any increase over time. The data in this study cannot exclude under-diagnosis and, to a lesser degree, under-registration as a partial explanation of the low incidence rates of malignant CNS tumours in children in Costa Rica.Ítem Chemical composition of PM 2.5 particles in Salamanca, Guanajuato Mexico: Source apportionment with receptor models(Science Direct, 2012-04) Herrera-Murillo, Jorge; Campos Ramos, Arturo; Ángeles García, Felipe; Blanco Jiménez, Salvador; Cárdenas, Beatriz; Mizohata, AkiraThe National Institute of Ecology, through Management General for Environmental Research and Training (DGCENICA) carried out a sampling campaign where a total of 21 elements were determined in 140PM 2.5 samples from one sampling site located in the city of Salamanca, Guanajuato-Mexico between November 2006 and November 2007. The annual average PM 2.5 concentration was 45μg/m 3 almost three times the Mexican Annual standard for PM 2.5. Mineral, organic and elemental carbon were the most important components present in particles PM 2.5. Two advanced receptor models, UNMIX and positive matrix factorization (PMF) were used for PM 2.5 source identification. Four and six sources were identified by UNMIX and PMF, respectively, from a combined dataset including 15 chemical species. Source categories were determined based on both, component abundances in the source profiles, and their temporal characteristics. Overall, different sources were identified as the major contributors: heavy fuels combustion, traditional brick production-agricultural burning, crustal, road traffic and secondary organic aerosols.