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URI permanente para esta colecciónhttp://10.0.96.45:4000/handle/11056/20509

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The opossum and other didelphids in the cultures of Costa Rican society and indigenous peoples: an approach to ecology and conservation
(Cold Spring Harbor Laboratory (Estados Unidos), 2024) Azofeifa Romero, Yara; Durán Alvarado, Francisco
The opossum Didelphis marsupialis, commonly referred to as the zorro pelón in Costa Rica, is a marsupial that holds significant representation in both Costa Rican and indigenous cultures, such as the Talamanca natives. This species, along with the other ten opossums found in Costa Rica, constitute one of the groups of mammals with the least representation in scientific literature. This study aims to (1) document the knowledge, uses, perceptions, and human-zorro pelón interactions through surveys conducted with individuals in three types of zones: rural, semi-urban, and urban; and (2) explore the presence of opossums in the 19th-century worldview of farmers and in the cosmovision of indigenous peoples. We performed an analysis on the text and Likert-scale data collected from 296 surveys conducted across seven provinces in Costa Rica. Nonparametric tests were conducted to assess whether the type of zone influenced the interactions and perceptions of individuals. Valuable information was obtained from key participants and informants regarding the behavior, observation sites, diet, and population trends of the species. The remarkable adaptability of the zorro pelón is evident in rural and semi-urban environments, but not in urban zones. The human-zorro pelón interaction data between the rural and semi-urban zones are similar, but these differ significantly from the urban zone. Although people surveyed generally have a positive perception of the opossum, there has been a notable devaluation over time when compared to the imaginary of indigenous cultures. Parallels were observed in the beliefs and uses of marsupials between pre-Columbian societies and contemporary Costa Rican societies. As part of the educational strategies for the conservation of marsupials, it is important to promote their appreciation and refute negative stereotypes, such as by informing about their ecological role and their ability to resist pathogens and venom. In this context, the rich symbolism of the opossum can be utilized to adapt the message to the various regions of America.
Phytotelm to assess bacterial multi-resistance to the antibiotics in a deep tropical forest
(Research Square Company (Estados Unidos), 2022-02-22) Sánchez-Vargas, Stephanny; Vargas, Paula; Vega-Corrales, Luis; Perez-Molina, Junior Pastor
Paradoxically, the use of antibiotics has resulted in the proliferation of resistant microorganisms in environments where they were not thought to be likely to appear. In this context, this research aimed to evaluate the phytotelmata as a matrix to detect the presence of bacterial strains with antibiotic resistance in the deep understory of tropical cloud forest and in a nearby rural town. The study was carried out in the Santa Elena Cloud Forest Reserve and the urban zone of the Santa Elena town, only 10 km. A compounded sample of phytotelm water was collected from 10—15 bromeliads and heliconia plants by site. Gram-negative bacterial strains found were evaluated to antibiotic susceptibility tests (13 antibiotics). In both sites, five strains presented multi-resistance to more than three antibiotics. Overall, antibiotics possessing cell wall synthesis inhibitor mechanisms were the most common with resistance for both sites followed by those acting as protein synthesis inhibitors. NMDS and PERMANOVA revealed that both environments had a similar response to antibiotic resistance (P > 0.05). The detection of bacterial multi-resistance to antibiotics in understory phytotelm water could become a quick tool to determine the degree of exposure of natural ecosystems to anthropogenic effects. This research opens the discussion of the potential dangers of the appearance of bacterial antibiotic multi-resistance in natural ecosystems, whose future impact is uncertain.
Antimicrobial activity of diverse chemotypes of Lippia graveolens against Aeromonas hydrophila isolated from tilapia
(Cold Spring Harbor Laboratory (Estados Unidos), 2023-07-25) García-Pérez, Josué; Perez-Sabino, Juan Francisco; Mendoza, Susana; Ribeiro da Silva, Antonio Jorge; Ulloa Rojas, Juan B.
Objetive: This study aimed to evaluate the antimicrobial efficacy of essential oil (EO) from diverse chemotypes of Lippia graveolens against oxytetracycline-resistant Aeromonas hydrophila, which primarily affects the tilapia aquaculture (Oreochromis sp) in Guatemala. Methodology: L. graveolens were collected in three departments in Guatemala, the EO was obtained by hydrodistillation and characterized by gas chromatography and mass spectrometry (GC/MS). Subsequently, an antimicrobial assay was conducted by screening the disk and dilution susceptibility tests, and evaluation of synergistic interactions among the chemotypes, each test being carried out in triplicate. Results: The analysis revealed the presence of twenty-seven compounds in the EO obtained from the chemotypes, the main class being monoterpene. The major constituents identified were cis-Dihydro-β-terpineol (8.84%) in chemotype I, carvacrol (51.82%) in chemotype II, and thymol (79.62%) in chemotype III. All EO chemotypes of L. graveolens demonstrated the ability to inhibit the A. hydrophila growth. Thymol chemotype exhibited the strongest inhibitory effect against bacterial growth, with a minimum inhibitory concentration (MIC) of 92.4 µg/mL and a minimum bactericidal concentration (MBC) of 184.8 µg/mL. Furthermore, the results suggest that there is no synergistic or additive effect when combining different chemotypes of L. graveolens. Conclusions: This the first report of L. graveolens chemotypes exhibiting antimicrobial activity against oxytetracycline-resistant A. hydrophila. The findings suggest the chemotype thymol could be a potential treatment for infections in the tilapia aquaculture in Guatemala.
Trophic guild and forest type explain phyllostomid bat abundance variation from human habitat disturbance
(Cold Spring Harbor Laboratory (Estados Unidos), 2020-02-16) Carballo-Morales, Jorge D.; Saldaña-Vázquez, Romeo A.; Villalobos Brenes, Federico
The loss of tropical forest cover caused by land-use change is causing a reduction in functional groups, such as trophic guilds. Phyllostomid bats (family Phyllostomidae) are essential in the Neotropics since they occupy up to six trophic guilds, and are pollinators, seed dispersers, and regulators of vertebrate and invertebrate populations. In this study, a series of meta-analyses were performed in order to analyse their response to habitat disturbance. Data were obtained through a comprehensive literature review whereby we measured the abundance of phyllostomid bats in disturbed habitats and conserved forests. We found that the abundance of phytophagous bats depends on the type of habitat disturbance and the type of forest where it occurs. On the other hand, animal-feeding bats reduce their abundance in any disturbed habitat regardless of disturbance type and forest type. No phylogenetic signal was found in the response of bats to habitat disturbance, nor was the response found to be dependent on the type of crop, the age of the secondary forest, or the distance to a conserved forest. These results demonstrate that feeding and the type of forest where the disturbance occurs are important aspects to understand the reduction of animal populations in the face of habitat destruction processes. This has implications on the conservation of species and their function in ecosystems.
Life zone and habitat disturbance do not explain the coexistence in Sturnira bat species
(Springer (Alemania), 2022-06-23) Mosquera Izquierdo, Esteban; Saldaña-Vázquez, Romeo A.; Sánchez, Mariano Sebastián; Villalobos Brenes, Federico; Castaño, John
One of the key questions in ecology is to understand the mechanisms that modulate the coexistence between syntopic species. Climate and habitat perturbation gradients have been proposed as moderators of species coexistence. The first is related to time availability and the diversity of food resources. The second is related to change in habitat structure that promotes changes in plant structure and diversity that impacts the diversity of other organisms. Although there is empirical evidence that supports these mechanisms to explain coexistence, they have not been evaluated quantitatively and on a wide geographic scale. Using phytophagous bat species of the genus Sturnira we evaluated both mechanisms. These bats are morphologically similar and are key organisms for the seed dispersal of Neotropical Forest plants. Using systematic review protocols, we obtained data of the occurrence and relative abundance of syntopic Sturnira species of different Neotropical forests. We used generalized linear models to evaluate the predictor power of Holdridge's life zones and habitat disturbance type to explain the evenness of syntopic Sturnira species. We found a highly Sturnira species evenness across life zones, going from 0.68–0.92, and found life zones with a maximum of eight Sturnira species coexisting in the same type of forest. The life zones and the type of disturbance do not explain the variation of evenness in Sturnira species. These results suggest that there is not a competitive exclusion among Sturnira species in tropical forests, and despite their ecological niche similarity, the environment allows the coexistence among these highly related species.
Atención plena (AP) y autorregulación emocional (AE) en la carrera enseñanza de las ciencias exactas y naturales
(2024-01-04) Salazar, Bryan; Pereira, José; Barrantes, Irán; Zamora, Adrián
Objetivo. Identificar la tendencia de utilización de la AP y la AE en los docentes y estudiantes de la carrera Enseñanza de las Ciencias de la Universidad Nacional de Costa Rica (UNA), como parte necesaria para la formación integral. Metodología. El estudio responde a una perspectiva cualitativa dominante, se llevó a cabo un análisis descriptivo utilizando frecuencias para identificar el uso de la AE y la AP en una muestra no probabilística seleccionada de docentes y estudiantes, la recolección de información se realizó mediante cuestionarios con preguntas abiertas y cerradas con escalas Likert. Las categorías de análisis emergentes se agruparon para aplicar una triangulación entre los datos. Resultados. Los hallazgos muestran diferencias entre las tendencias de utilización de los rasgos de AP en las poblaciones, los estudiantes tienden a regular sus emociones más mediante la supresión expresiva que los docentes y presentan la misma puntuación en la tendencia de las estrategias desadaptativas y adaptativas, la más utilizada fue la rumiación (estrategia desadaptativa). Conclusiones. Se observo en los estudiantes una divergencia en las estrategias para regular las emociones, al encontrar una alta tendencia de utilización en las estrategias desadaptativas y en la supresión expresiva, al igual que una menor tendencia en el rasgo de aceptación de la AP. Recomendaciones. Es necesario reconocer la importancia de integrar contenidos para desarrollar habilidades blandas en los currículos de formación docente desde la psicología cognitiva y la regulación de los procesos atencionales.
The interplay between irrigation and fruiting on branch growth and mortality, gas exchange and water relations of coffee trees
(Oxford University Press, 2021) Almeida, Wellington L.; Avila, Rodrigo; Perez-Molina, Junior Pastor; Barbosa, Marcela L.; Marcal, Dinorah M.; De Souza, Raylla P. B.; Martino, Pedro B.; Cardoso, Amanda A.; Martins, Samuel C.V.; DaMatta, Fabio M.
The overall coordination between gas exchanges and plant hydraulics may be affected by soil water availability and source-to-sink relationships. Here we evaluated how branch growth and mortality, leaf gas exchange and metabolism are affected in coffee (Coffea arabica L.) trees by drought and fruiting. Field-grown plants were irrigated or not, and maintained with full or no fruit load. Under mild water deficit, irrigation per se did not significantly impact growth but markedly reduced branch mortality in fruiting trees, despite similar leaf assimilate pools and water status. Fruiting increased net photosynthetic rate in parallel with an enhanced stomatal conductance, particularly in irrigated plants. Mesophyll conductance and maximum RuBisCO carboxylation rate remained unchanged across treatments. The increased stomatal conductance in fruiting trees over nonfruiting ones was unrelated to internal CO2 concentration, foliar abscisic acid (ABA) levels or differential ABA sensitivity. However, stomatal conductance was associated with higher stomatal density, lower stomatal sensitivity to vapor pressure deficit, and higher leaf hydraulic conductance and capacitance. Increased leaf transpiration rate in fruiting trees was supported by coordinated alterations in plant hydraulics, which explained the maintenance of plant water status. Finally, by preventing branch mortality, irrigation can mitigate biennial production fluctuations and improve the sustainability of coffee plantations.
Chromosome-Level Genome Reveals the Origin of Neo-Y Chromosome in the Male Barred Knifejaw Oplegnathus fasciatus
(Elsevier Inc., 2020-04-24) Xiao, Yongshuang; Xiao, Zhizhong; Ma, Daoyuan; Zhao, Chenxi; Liu, Lin; Wu, Hao; Nie, Wenchao; Xiao, Shijun; Liu, Jing; Li, Jun; Herrera-Ulloa, Angel
The barred knifejaw, Oplegnathus fasciatus, is characterized by an X1X2Y system with a neo-Y chromosome for males. Here, a chromosome-level genome was assembled to investigate the origin of neo-Y chromosome to the male O. fasciatus. Twenty-three chromosomes corresponding to the male karyotypes were scaffolded to 762-Mb genome with a contig N50 length of 2.18 Mb. A large neo-Y chromosome (Ch9) in the male O. fasciatus genome was also assembled and exhibited high identity to those of the female chromosomes Ch8 and Ch10. Chromosome rearrangements events were detected in the neo-chromosome Ch9. Our results suggested that a centric fusion of acrocentric chromosomes Ch8 and Ch10 should be responsible for the formation of the X1X2Y system. The high-quality genome will not only provide a solid foundation for further sex-determining mechanism research in the X1X2Y system but also facilitate the artificial breeding aiming to improve the yield and disease resistance for Oplegnathus.

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