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1.
Landsc Ecol ; 39(6): 112, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38817738

RESUMEN

Context: Urbanization is rapidly increasing worldwide, with about 60% of the global population currently residing in cities and expected to reach 68% by 2050. In Latin America's tropical Andes region, managing these changes poses challenges, including biodiversity loss and vulnerability to climate change. Objectives: This study assesses urban growth and agricultural intensification impacts on the ecological functionality of metropolitan green infrastructures and their capacity to provide ecosystem services using a landscape sustainability and sociometabolic approach. Specifically, it aims to identify landscape configurations promoting socio-ecological sustainability amidst rapid urbanization. Methods: A landscape-metabolic model (IDC) was applied to evaluate the interactions between land use changes and ecosystem functions in the metropolitan region of Cali. Results: Agricultural intensification and industrialization, coupled with uncontrolled urban growth, have significantly transformed the landscape, posing threats to its sustainability. The prevailing biocultural landscapes hold a substantial potential to provide essential ecosystem services to the metropolis. The IDC offers an approach that utilizes a land cover map and agricultural production/metabolism data to calculate an indicator closely related to ecosystem services and multifunctionality. Conclusions: The IDC model stands out for efficiently capturing landscape dynamics, providing insights into landscape configuration and social metabolism without extensive resource requirements. This research highlights the importance of adopting a landscape-metabolic and green infrastructure framework to guide territorial policies in the tropical Andes and similar regions. It stresses the need for informed land use planning to address challenges and leverage opportunities presented by biocultural landscapes for regional sustainability amidst rapid urbanization and agricultural expansion.

2.
Rev. biol. trop ; 67(2)abr. 2019.
Artículo en Inglés | LILACS-Express | LILACS | ID: biblio-1507495

RESUMEN

Hesperiidae is one of the most diverse families of butterflies in Costa Rica, with approximately 486 species. Even so, there are few butterfly lists where this group has been included. In this paper, we present information on seasonality, abundance and natural history features of this family for the Leonelo Oviedo Ecological Reserve (RELO), a 2 ha forest embedded in an urban matrix. Over the course of two years, a monthly sampling was carried out on a 270 m trail across the Reserve from 08:00 to 12:00, collecting all the individuals located within 5 m on each side of the trail. To better represent the richness, individuals were also randomly collected for more than ten years, but the butterflies collected in this way were not included in the statistical analysis. Photographs were taken of all the species in order to provide an identification guide. For the cryptic species, drawings and dissections of the genitalia were made. For the community indexes we used Microsoft Excel and the Shannon index with base two logarithm. For the summary of the monthly data analysis were done according to dry and wet season. For a comparison of richness and abundance we did a g-test to evaluate if there are differences between seasons; however, with the use of the R package vegan a hierarchical cluster analysis was done using the Jaccard index with Wards minimum variance agglomerative method. With R package pvclust the uncertainty of the clusters based on a bootstrap with 10 000 iterations. 423 individuals of 49 species were included in the statistical analysis, from a total of 435 individuals of 58 species. A tendency to greater richness and abundance of skippers was found during the dry season. Through the cluster analysis, it was possible to determine that in relation to the diversity of skippers, both wet seasons are grouped significantly (P = 0.05). The dry seasons are also grouped significantly (P = 0.05). The reserve has connectivity with other green areas via a stream. During the wet season, plant growth increases connectivity, which could lead to the entry of new individuals of different species that are not permanent residents of RELO and establish small populations, increasing the richness and abundance of species. This added to the variation in the occurrence of some species of butterflies in response to seasonal variations and differences in the availability of resources in different seasons explains the grouping of species between seasons.


Con aproximadamente 486 especies, Hesperiidae es una de las familias más diversas de mariposas de Costa Rica. A pesar de eso, en pocas listas de especies locales son incluidas. En este trabajo, presentamos información sobre la estacionalidad, abundancia e historia natural de los hespéridos de la Reserva Ecológica Leonelo Oviedo. Ésta reserva se encuentra dentro de una matriz urbanizada y por un período de dos años se realizaron muestreos mensuales a lo largo de un sendero de 270 m que la atraviesa. Las recolectas se llevaron a cabo desde las 08:00 hasta las 12:00, atrapando todos los individuos encontrados a cada lado del sendero a una distancia de hasta 5 m. Para representar mejor la riqueza de especies, se siguió recolectando individuos de manera aleatoria por más de diez años posteriores al muestreo inicial. Consecuentemente, estos individuos no fueron incluidos en el análisis estadístico realizado. Se tomaron fotografías de todas las especies obtenidas en total, para proporcionar una guía de identificación de especies. Ademas, para las especies crípticas se realizaron disecciones e ilustraciones de los genitales masculinos. Para el análisis de diversidad se utilizó el índice de Shannon con logaritmo en base dos y analizando los datos por separado de las estación lluviosa y seca. Para la comparación de riqueza y abundancia se realizó una prueba G y se obtuvo que hay mayor diversidad y abundancia durante la estación seca. Se utilizó el paquete vegan R para un análisis de conglomerados de Jaccard con un indice Ward de mínima varianza. Con el Paquete R pvclust la incertidumbre de los conglomerados se realizó con un bootstrap de 10 000 interacciones. 423 individuos de 49 especies fueron incluidas en el análisis estadístico, de un total de 435 individuos de 58 especies tratadas en este trabajo. Con el análisis de conglomerados fue posible determinar que la diversidad de Hesperiidae en las dos estaciones lluviosas analizadas se agrupan significativamente (P = 0.05). Lo mismo que sucede con las estaciones secas (P = 0.05). La Reserva presenta conectividad con otras áreas boscosas a través de una quebrada. Durante la estación lluviosa, el crecimiento vegetativo aumenta el paso de individuos lo que puede propiciar la llegada de nuevas especies que no necesariamente son residentes permanentes de la Reserva y establecerse en pequeñas poblaciones que incrementan la diversidad y abundancia temporalmente, Lo anterior, mas las variaciones estacionales en la disponibilidad de recursos explican la similitud de la composición de especies entre cada una de las estaciones.

3.
P R Health Sci J ; 36(1): 5-10, 2017 03.
Artículo en Inglés | MEDLINE | ID: mdl-28266693

RESUMEN

OBJECTIVE: This study aimed to establish a profile of the ultrasound-guided thyroid fine-needle aspiration biopsies (FNABs) performed at the endocrinology clinics of the University Hospital of Puerto Rico. METHODS: A retrospective study was conducted to assess all the thyroid FNABs performed from July 1, 2011, to December 31, 2013. Data on socio-demographic, FNAB cytology, surgery, and histopathology were collected from medical records. A chi-square test was used to assess associations between predictors and outcome. McNemar's test was used to compare FNAB cytology and histopathology results. RESULTS: A total of 240 FNABs were performed on 192 patients; 91.2% were female. The distribution of the cytological diagnoses was as follows: 181 (75.4%) were benign; 39 (16.3%) were non-diagnostic; 15 (6.3%) were indeterminate; and 5 (2.1%) were malignant. A malignant cytology was more likely in patients younger than 45 y/o than in their older counterparts (p = 0.01); a similar result was found for patients who smoked vs. those who did not (p = 0.02). Benign nodules were more likely to be larger than 1 cm than were those that were malignant (88.2% vs. 25%). Histopathology results were available for 38 nodules; there were no statistically significant differences between the cytology and histopathology results (p>0.05). The sensitivity and specificity for FNAB cytology were 75% and 100%, respectively. Of the nodules with an initial indeterminate cytology (47%), 71% demonstrated, ultimately, benign histopathology. CONCLUSION: In our study, most of the FNABs performed yielded a benign cytology. A high concordance was shown between cytology and histology. For those with indeterminate cytology, the majority of cases demonstrated benign histopathology. These data suggest the need to implement other approaches, such as the development and subsequent use of molecular markers, to improve our diagnostic and therapeutic strategies, this according to our population-based disease prevalence.


Asunto(s)
Biopsia con Aguja Fina/métodos , Glándula Tiroides/patología , Neoplasias de la Tiroides/diagnóstico , Nódulo Tiroideo/diagnóstico , Adulto , Factores de Edad , Anciano , Anciano de 80 o más Años , Femenino , Hospitales Universitarios , Humanos , Masculino , Persona de Mediana Edad , Puerto Rico , Estudios Retrospectivos , Sensibilidad y Especificidad , Fumar/epidemiología , Ultrasonografía Intervencional/métodos , Adulto Joven
4.
Regul Toxicol Pharmacol ; 77: 100-8, 2016 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-26930635

RESUMEN

During the past two decades the use and refinements of imaging modalities have markedly increased making it possible to image embryos and fetuses used in pivotal nonclinical studies submitted to regulatory agencies. Implementing these technologies into the Good Laboratory Practice environment requires rigorous testing, validation, and documentation to ensure the reproducibility of data. A workshop on current practices and regulatory requirements was held with the goal of defining minimal criteria for the proper implementation of these technologies and subsequent submission to regulatory agencies. Micro-computed tomography (micro-CT) is especially well suited for high-throughput evaluations, and is gaining popularity to evaluate fetal skeletons to assess the potential developmental toxicity of test agents. This workshop was convened to help scientists in the developmental toxicology field understand and apply micro-CT technology to nonclinical toxicology studies and facilitate the regulatory acceptance of imaging data. Presentations and workshop discussions covered: (1) principles of micro-CT fetal imaging; (2) concordance of findings with conventional skeletal evaluations; and (3) regulatory requirements for validating the system. Establishing these requirements for micro-CT examination can provide a path forward for laboratories considering implementing this technology and provide regulatory agencies with a basis to consider the acceptability of data generated via this technology.


Asunto(s)
Anomalías Inducidas por Medicamentos/diagnóstico por imagen , Huesos/diagnóstico por imagen , Biología Evolutiva/métodos , Feto/diagnóstico por imagen , Pruebas de Toxicidad/métodos , Microtomografía por Rayos X , Animales , Huesos/anomalías , Huesos/efectos de los fármacos , Consenso , Biología Evolutiva/normas , Feto/anomalías , Feto/efectos de los fármacos , Guías como Asunto , Humanos , Variaciones Dependientes del Observador , Valor Predictivo de las Pruebas , Reproducibilidad de los Resultados , Pruebas de Toxicidad/normas , Microtomografía por Rayos X/normas
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