National Autonomous University of Nicaragua

About: National Autonomous University of Nicaragua is a education organization based out in Managua, Nicaragua. It is known for research contribution in the topics: Population & Public health. The organization has 775 authors who have published 715 publications receiving 9791 citations.

Aplicación de la técnica nuclear de Cesio - 137 para estimar la erosión de los suelos en la subcuenca del Río Ochomogo

Abstract: El uso de la contaminacion radiactiva por 137Cs (Cesio - 137) en la atmosfera ha sido usado como trazador en este estudio para estimar la erosion y conocer su redistribucion en perfiles de suelos ubicados en la subcuenca del Rio Ochomogo. Se colectaron al azar 10 submuestras del perfil de suelos en los cinco sitios de estudio y dos de referencia en las dos zonas de estudio. Los suelos seleccionados se usan para diferentes cultivos como son cana de azucar, arroz, platano, maiz y pasto para ganado. Las muestras se colectaron en perfiles de 0-5 cm, 5-10 cm, 10-20 cm y 20-30 cm, totalizando 28 muestras y fueron analizadas en un espectrometro gamma. A partir de las actividades de 137Cs se calculo el inventario para cada muestra y se determinaron las perdidas de suelo aplicando el Modelo Proporcional. Se registraron actividades de 137Cs de entre no detectables hasta 0.72 Bq kg-1 e inventarios de hasta 114.81 Bq m-2. Los resultados de las mediciones de 137Cs mostraron que la actividad en los suelos de los sitios de estudio esta fuertemente condicionada por el uso y tipo del suelo. Los suelos que presentaron mas erosion en orden descendente son los utilizados para el cultivo de maiz, cana de azucar, platano, pasto para ganado y arroz. En general, los valores de las perdidas de suelos estimados en los perfiles analizados se corresponden con la clasificacion de erosion nula o ligera de acuerdo a las directrices internacionales establecidas. Todas las estimaciones calculadas para los suelos en las dos zonas de estudio implicaron la importancia del proceso de erosion lo que podria convertirse en un problema ambiental de primera magnitud en la subcuenca.

Optimizing nursery and plantation methods to grow Cedrela odorata seedlings in tropical dry agroecosystems

Abstract: Cedrela odorata (Spanish cedar) is a valuable multi-purpose tree which Central American rural communities and farmers give priority to introducing in pastures and home gardens. In order to propose realistic methods for C. odorata production in local nurseries in the dry tropical region of Nicaragua, we studied: (a) the ability of locally collected C. odorata seeds to germinate, (b) seed response to storage under ambient conditions or under cold storage, (c) the effects of irradiance and watering during cultivation on seedling morphology and post-transplantation survival, and (d) the effects of competition from grasses on C. odorata seedlings transplanted to pastures. Seed germination ranged from 55 to 66% and remained constant after 6 months of storage under ambient conditions or cold storage. C. odorata seedling morphology was sensitive to irradiation and watering in the nursery growing period. Deep shade reduced seedling biomass and leafiness and increased specific leaf area and root-to-shoot ratio. Water shortage increased root mass ratio and root-to-shoot ratio and decreased leaf mass ratio. Post-transplantation success was favored by weeding, and was the highest for seedlings grown under deep shade and water restrictions.

uvby - β Photoelectric Photometry of the Open Clusters NGC 6811 and NGC 6830

Abstract: From uvby − β photometry of the open clusters NGC 6811 (75 stars), and NGC 6830 (19 stars) we were able to determine membership of the stars to each cluster, and fix the age and reddening for each. Since several short period stars have recently been found, we have carried out a study of these variables.

Rectovaginal group B streptococcus colonization among pregnant women in Nicaragua: a systematic review and meta-analysis

Abstract: Background: Maternal colonization with group B Streptococcus (GBS) is a predictor of neonatal sepsis. In Nicaragua, neonatal sepsis is a major cause of hospitalization, but it can be prevented with...

Ceroid granulomas of the gallbladder. A clinicopathologic study of nine cases.

Abstract: Nine cases of ceroid granulomas of the gallbladder were found in 125 surgically excised gallbladders during a one year review (7.35%), corresponding to an estimated incidence of 2.1 cases per 100,000 inhabitants per annum. Seven patients were under 50 year of age. Four patients presented symptoms and signs of chronic cholecystitis. However, in five cases, a mass in the right hypochondrium was palpated, mimicking a carcinoma of the gallbladder. The lesion was characterized by intramural or mucosal yellow-brown nodules composed of ceroid-laden histiocytes. The presence of intramural destructive necrosis in one case suggests that ceroid granulomas of the gallbladder have the potential of developing fistulae or perforations. Rupture of the Rokitansky-Aschoff sinuses and mucosal ulceration with intramural liberation of bile were implicated in the pathogenesis. The characteristic microscopic appearance, as well as the ceroid nature of the granules revealed by histochemical and ultrastructural studies, support the view that ceroid granulomas of the gallbladder should be recognized as a distinct histo-pathological entity. It is important to recognize this lesion as it can be mistaken for carcinoma and may be responsible for serious complications, such as fistulae or perforation.