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546,196 artículos
Año:
2022
ISSN:
1729-519X
Gamarra Choque, Pilar María; Pante Salas, Giovanna Gladys
Editorial Ciencias Médicas
Resumen
Introducción: El embarazo en la adolescencia es un problema de salud pública, con reconocida influencia en los aspectos socioeconómicos y psicoemocionales de la gestante, que puede influir en los indicadores de salud materna.Objetivo: Determinar el impacto del embarazo adolescente sobre los indicadores de salud materna y perinatal.Material y Método: Estudio retrospectivo y descriptivo, en una población de 5 920 gestantes atendidas en el Hospital San Juan de Lurigancho durante el año 2018, para la determinación de indicadores de salud materna, como la tasa de mortalidad y morbilidad materna (TMM y TMbM) y perinatal (TMP y TMbP), considerando dos grupos de análisis, mujeres gestantes entre 10 y 19 años y mayores de 19 años de edad.Resultados: Se atendieron 14,5 % partos de mujeres adolescentes entre 10 y 19 años de edad, grupo en el cual se presentaron TMbM y TMbP de 10,8 y 80,3 respectivamente, en contraposición a las tasas de 8,8 y 43,3 en el grupo de mujeres gestantes mayores de 19 años. La TMP fue de 6,9 y 10,4 en los grupos de gestantes adolescentes y mujeres adultas, respectivamente, mientras que la TMM fue de 19,9 en mujeres adultas. No se registró fallecimiento de pacientes adolescentes.Conclusiones: El embarazo en la adolescencia influyó significativamente en el indicador de salud materna TMbP, probablemente debido a la falta de control prenatal temprano, además de la inmadurez y la estructura ósea de la pelvis, siendo factores que pueden determinar problemas de salud en los neonatos.
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Año:
2022
ISSN:
2215-2075, 0034-7744
Arias, Adriana Martínez; González Salcedo, Luis Octavio; Benavides Martínez, Iván Felipe; Josephraj Selvaraj, John
Universidad de Costa Rica
Resumen
Introduction: The prediction of potential fishing areas is considered one of the most immediate and practical approaches in fisheries and is an essential technique for decision-making in managing fishery resources. It helps fishermen reduce their fuel costs and the uncertainty of their fish catches; this technique allows to contribute to national and international food security. In this study, we build different combinations of predictive statistical models such as Generalized Linear Models and Generalized Additive Models. Objective: To predict the spatial distribution of PFZs of the dolphinfish (Coryphaena hippurus L.) in the Colombian Pacific Ocean. Methods: We built different combinations of Generalized Linear Models and Generalized Additive Models to predict the Catch Per Unit Effort of C. hippurus captured from 2002 to 2015 as a function of sea surface temperature, chlorophyll-a concentration, sea level anomaly, and bathymetry. Results: A Generalized Additive Model with Gaussian error distribution obtained the best performance for predicting PFZs for C. hipurus. Model validation was performed by calculating the Root Mean Square Error through a cross-validation approach. The R2 of this model was 50 %, which was considered suitable for the type of data used. January and March were the months with the highest Catch per Unit Effort values, while November and December showed the lower values. Conclusion: The predicted PFZs of C. hippurus with Generalized Additive Models satisfactorily with the results of previous research, suggesting that our model can be explored as a tool for the assessment, decision making, and sustainable use of this species in the Colombian Pacific Ocean.
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Año:
2022
ISSN:
2215-2075, 0034-7744
Ali Elhassan, Moawia Mohammed; Monge-Nájera, Julián; Ho, Yuh-Shan
Universidad de Costa Rica
Resumen
Introduction: Sudan is the third largest country in Africa and has rich reserves of petroleum and other ground resources, but its per capita Gross Domestic Product is only $808 and researchers work in insufficient institutional facilities and with little funding. Previous studies about its scientific productivity have been limited to specific subjects and relatively short periods, with no large analyses until now. Objective: To analyze the scientific output of Sudan in depth, considering all research areas and several decades of scientific activity. Methods: We retrieved the documents with “Sudan” in field country in the Science Citation Index Expanded for the period 1900-2019. Results: We retrieved over 9 000 publications and found that most were articles; that citation was higher for review articles and book chapters, and that this index mostly covered articles in English. Beginning in 1972, the number of publications in this database has increased rapidly. The citation lifespan indicates slow growth in the Sudanese scientific literature, and collaboration is frequent both nationally and internationally, possibly because the scarce resources make collaboration almost compulsory. Most external collaboration is done with Saudi Arabia but citation is higher for articles resulting from international megaprojects, led by Europe and the USA, in which Sudanese researchers play secondary roles. Research focusses on applied technological subjects with little innovation value. Women play a smaller role in Sudanese science. Conclusions: Our recommendations for Sudanese science include increasing the number of women in leading research positions; providing funding directly to researchers (i.e., bypassing bureaucratic bodies); increasing basic research to avoid stagnation; training Sudanese researchers for leading positions; and identifying specific research areas where Sudan can lead in its region.
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Año:
2022
ISSN:
2215-2075, 0034-7744
Segura-Ulate, Ismael; Bolívar-González, Alejandro; Madrigal-Redondo, Germán; Nuñez-Corrales, Santiago; Gatica-Arias, Andrés
Universidad de Costa Rica
Resumen
Introduction: Most successful cases of COVID-19 pandemic mitigation and handling have relied on extensive reverse-transcription quantitative polymerase chain reaction (RT-qPCR). However, many emerging economies have struggled with current molecular testing demands due to economic, technical and technological constraints. Objective: To define a potential diagnostic protocol to increase testing capacity in current and post-pandemic conditions. Methods: We reviewed the literature, patents and commercial applications, for alternatives. Results: We found a good potential in saliva samples, viral inactivation and quick RNA extraction by heating; the use of an isothermal technology such as loop mediated isothermal amplification (LAMP) and naked eye test-result visualization by in-tube colorimetry or turbidity. Conclusions: Saliva samples with quick RNA extraction by heating and colorimetric LAMP are promising options for countries with economic and infrastructure limitations.
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Año:
2022
ISSN:
2215-2075, 0034-7744
Quinto Mosquera, Harley; Moreno Hurtado, Flavio H.
Universidad de Costa Rica
Resumen
Introduction: Fine root dynamics include production, turnover and decomposition; they are crucial to forest health, affect the entire biogeochemical complex of the ecosystem, and consequently, they substantially affect carbon balance. However, the influence of environmental factors and soil nutrient limitation on fine roots presents considerable uncertainties and has not been studied in tropical forests with more than 7 000 mm annual rainfall. Objective: To measure the effect of fertilization on fine roots in the high precipitation Chocó forest. Methods: We worked in two sites of the Chocó region, Colombia (August 2014-May 2015), where rainfall exceeds 10 000 mm per year. We applied five fertilization treatments (N, P, K, NPK and Control) to two soil type plots. Soil cylinders were removed at pre-established intervals to measure roots. Results: Phosphorus applications increased fined roots; and more fine roots were produced in sandy than in loam soil. The effects of fertilization were related, but not clearly determined by edaphic conditions. Conclusions: In this Chocó forest, the production of fine roots was higher in sandy and nutrient-rich soils but belowground net primary productivity was limited by the content of edaphic Phosphorus.
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Año:
2022
ISSN:
2215-2075, 0034-7744
Villegas, Alejandro; Rojas-Santoyo, Aliet; Ulloa-Arvizu, Raúl
Universidad de Costa Rica
Resumen
Introduction: There is low evidence of genetic diversity and hybridization processes within Crocodylus acutus and C. moreletii populations. Objetive: To evaluate genetic diversity and some phylogenetic relationships in wild and captive populations of C. acutus and C. moreletii using the Barcode of Life Data System (COX1, cytochrome C oxidase subunit 1 gene). Methods: 28 individuals phenotypically like C. acutus located in the state of Guerrero, Oaxaca and Quintana Roo were sampled, as well as animals belonging to C. moreletii located in the states of Tabasco, Campeche, and Quintana Roo. 641 base pairs of nucleotide sequence from COX1 were used to obtain the haplotype and nucleotide diversity per population, and a phylogenetic and network analysis was performed. Results: Evidence of hybridization was found by observing C. moreletti haplotypes in animals phenotypically determined as C. acutus, as well as C. acutus haplotypes in animals classified as C. moreletti. Low haplotypic diversity was observed for C. acutus (0.455 ± 0.123) and for C. moreletii (0.505 ± 0.158). A phylogenetic tree was obtained in which the sequences of C. acutus and C. moreletii were grouped into two well-defined clades. Organisms identified phenotypically as C. acutus but with C. moreletii genes were separated into a different clade within the clade of C. moreletii. Conclusions: There are reproductive individuals with haplotypes different from those of the species. This study provides a small but significant advance in the genetic knowledge of both crocodile species and the use of mitochondrial markers, which in this case, the COX1 gene allowed the detection of hybrid organisms in wild and captive populations. Conservation efforts for both species of crocodiles should prevent the crossing of both threatened species and should require the genetic identification of pure populations, to design effective conservation strategies considering the possibility of natural hybridization in areas of sympatry.
Palabras clave: ADN mitocondrial; citocromo C oxidasa; diversidad haplotípica; diversidad de nucleótidos; hibridación, Sistema de código de barras de la vida.
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Año:
2022
ISSN:
2215-2075, 0034-7744
Serna, Juan Pablo; Fernandez, David; Velez, Fabio; Ruiz, Julián; Breckling, Broder; Aguirre, Néstor
Universidad de Costa Rica
Resumen
Introduction: Analysis of functional feeding groups (FFG) in aquatic macroinvertebrates is important in understanding the structure, function, and dynamics of ecological processes ecosystems. Modularity refers to the degree of compartmentalization of food webs and varies between -1 and 1. A network with a modularity value close to 1 is resilient to disturbances and can be interpreted as an indicating factor for the stability of communities. Objective: In this study, we analyzed the trophic structure of benthic macroinvertebrates in La Nitrera stream, the San Juan River, and the Cauca River. Methods: The study was supported by ecological networking techniques using Gephi software. We studied nine sites in dry, rainy, and transition seasons in 2017 and 2018, monitoring changes in the altitude gradient. At each of the sites, the organisms were captured and determined, and physicochemical and hydraulic information was obtained. Results: The variance component analysis allowed to explain the variability of the data by relating the following environmental variables: FFG, diversity, richness, modularity, season, and time. Simple multifactorial ANOVA indicated that significant changes in FFG were associated with altitude, and modularity to time. The allocation of the FFG was done by stomach analysis and secondary information. Conclusion: The transition season had the highest modularity, possibly due to the recolonization of some biotopes caused by the decrease in riverbed velocity. La Nitrera and San Juan presented higher values than the Cauca, which may indicate that the altitudinal change and velocity of water currents affects the compartmentalization of the network.
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Año:
2022
ISSN:
2215-2075, 0034-7744
Silveira, Alan Bernardes da; Carvalho, Samuel de Padua Chaves e; Nicoletti, Marcos Felipe; Silva, Carlos Alberto; Drescher, Ronaldo; Carvalho, Mariana Peres de Lima Chaves e; Madi, Joao Paulo Sardo; Topanotti, Larissa Regina; Zeviani, Walmes Marques; Andrade, Valdir Carlos Lima de
Universidad de Costa Rica
Resumen
Introduction: Inventories are essential for forest management, but, in the Amazon region, the absence of standardization produces information loss, low accuracy, and inconsistent measurements. This prevents valid comparisons and compromises the use of information in networks and software. Sampling unit size is of key importance in the inventory of native forests, particularly regarding accuracy and costs. Objective: To identify a plot size that provides adequate precision for dendrometric parameters in the Amazon. Methods: In Cotriguaçu, Mato Grosso, Brazil, we tested four plot sizes with six repetitions each: 2 500, 5 000, 7 500, and 10 000 m². We measured diameter at breast height, population density, basal area, and biomass. We applied Shannon and Jaccard indexes; Weibull 2P and Gamma functions to fit the diametric distribution; and the Akaike Information Criterion for the best model. Results: There was a directly proportional relationship between plot area and population similarity, but diversity did not indicate significant alterations. Plot size did not affect dendrometric attributes and diametric distribution. Larger plot areas led to lower coefficients of variation and smaller confidence intervals. The Gamma function was the best model to represent the distributions of different plot sizes. Conclusions: For similar forests, we recommend the 2 500 m² plot to evaluate diameter at breast height, population density, basal area, and biomass.
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Año:
2022
ISSN:
2215-2075, 0034-7744
Yaney-Keller, Adam; Santidrián Tomillo, Pilar; Jordan, Mark A.; Lopez Navas, Javier Francisco; Paladino, Frank V.
Universidad de Costa Rica
Resumen
Introduction: Tropical dry forests and mangroves, two of the world’s most endangered ecosystems, each host a different set of environmental conditions which may support unique assemblages of species. However, few studies have looked at the unique vertebrate biodiversity in regions where both habitats occur side-by-side. Objective: To assess the vertebrate diversity and patterns of habitat usage in a mangrove and tropical dry forest matrix in an unprotected region of Northwestern Costa Rica. Methods: The study was conducted in a 7 km2 matrix of mangrove and tropical dry forests between Cabuyal and Zapotillal bays in Northwestern Costa Rica, South of Santa Rosa National Park. From September 2017 to March 2018, we used 13 automatic camera traps over 1 498 trap days to capture species utilizing the region and assess their patterns of habitat usage both spatially and temporally. Results: Seventy vertebrate species from 42 families in 27 orders were detected, including several globally threatened species. Over half of all species were detected in only one habitat, particularly amongst avian (78 %) and mammalian (42 %) species. Tropical dry forests hosted the greatest number of unique species and supported a greater percentage of herbivores than mangrove or edge habitats, which were dominated by carnivorous and omnivorous species. Mean detections per camera trap of all species increased significantly from the coldest and wettest month (Oct) to the hottest and driest months (Jan & Feb) in tropical dry forests. Sample-based rarefaction analysis revealed that survey length was sufficient to sample the tropical dry forest and edge habitats, though mangroves require further sampling. Conclusions: Taxa found to utilize different forest types may utilize each for different stages of their life cycle, moving between areas as environmental conditions change throughout the year. General patterns of global biodiversity favoring carnivore and omnivore usage of mangrove forests was confirmed in our study.
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Año:
2022
ISSN:
2215-2075, 0034-7744
Avila, Isabel Cristina; Giraldo, Alan
Universidad de Costa Rica
Resumen
Introduction: Marine mammals are being affected by different threats that cause a negative effect on species or populations. To mitigate these impacts, it is necessary to establish the spatial and temporal variation of these threats for each species. Objective: to make a quantitative visualization of threats affecting marine mammal species in Colombia in the last three decades, and to identify actions required to mitigate those threats. Methods: In the present study, a review and georeferencing of the documented threats for marine mammals present in Colombia (35 species) between 1991 and 2020 was carried out. A database with identified, localized and dated threats was generated. Additionally, risk maps were created, superimposing the different taxa and threats to be able to visualize a general panorama of where the threats are occurring in Colombia. Results: 63 % of the marine mammals in Colombia (22 species) registered at least one threat. Bycatch and interactions with fishing gear affected most species (16 species), followed by direct capture (8 species) and vessel traffic / transit (6 species) and alteration of ocean physics (6 species). Direct human activities, mainly fishing, was the main source of threat that affected most of the species (18 species). The most affected species, in terms of the greater diversity of threats they face, are the humpback whale (Megaptera novaeangliae), the Caribbean West Indian manatee (Trichechus manatus), the marine tucuxi (Sotalia guianensis) and the bottlenose dolphin (Tursiops truncatus). The maps obtained show that 99.9 % of Colombia's marine territory presents some degree of risk for the marine mammal community. High-risk areas were identified for the Pacific in the surroundings of Buenaventura, Guapi, Gulf of Cupica and Bahía de Tumaco, and for the Caribbean in the Gulf of Urabá, Gulf of Darién, Gulf of Morrosquillo, surroundings of Barranquilla and Ciénaga Grande de Santa Marta and in the Gulf of Coquivacoa. In general, the pattern of areas at risk based on documented threats for marine mammals in Colombia has remained similar through the three last decades, however areas at risk by pollution and resource depletion have increased in the last decade 2011-2020. Conclusion: Marine mammals in Colombia currently are in risk due to several threats, especially related with fishing, harvesting and shipping activities, and mainly in coastal areas. It is recommended to evaluate in detail the status of marine mammalian species in Colombia, especially in the high-risk areas identified in the present study, and to take management actions that promote marine mammal conservation.
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