179 research outputs found
Interés privado versus interés público: sistemas energéticos y políticas climáticas en Canadá y México
Pupal surveys for Aedes aegypti surveillance and potential targeted control in residential areas of Mérida, México.
A mosquito larval-pupal survey was conducted in 1,160 households of the Mexican city of Mérida during the rainy season of 2003 to determine their differential productivity for Aedes aegypti. Larvae and pupae were detected in 15 broad categories of container types. All breeding sites were found in the patios (backyards) and were potentially rain filled. Ae. aegypti pupae were produced from all categories of breeding site, and no single container type was predominately responsible for pupal production. The most productive buckets comprised 42% of the pupae-positive containers and provided 34% of the total pupae collected. Pupal production in buckets, together with plastic rubbish, pet dishes and basins, utensils for cooking and washing, tires, and flowerpots, accounted for almost 87% of pupal production. However, the most important pupal producers had low infestation indices for immature forms, illustrating that the use of positive-container indices can underestimate the importance of certain breeding sites. Overall, 40% of containers that were observed harboring Ae. aegypti pupae were classified as disposable. The remaining containers were considered useful, although some were seldom used. The discussion focuses on the potential utility of the pupal survey for targeting control, and its resulting pupae-per-person entomological indicator, both for comparison with a theoretical threshold for dengue transmission and for targeting vector control in this Mexican city
Protecting Free-Living Dormice: Molecular Identification of Cestode Parasites in Captive Dormice (Muscardinus avellanarius) Destined for Reintroduction
The success of any population translocation programme relies heavily on the measures implemented to control and monitor the spread of disease. Without these measures, programmes run the risk of releasing immunologically naïve species or, more dangerously, introducing novel infectious agents to native populations. As a precaution, a reintroduction programme for the common or hazel dormouse, Muscardinus avellanarius, in England screens dormice before release following captive breeding. Using PCR sequencing of a range of genes, we tested whether the same species of tapeworm(s) were present in captive and free-living dormice. Whilst only Rodentolepis straminea were identified in free-living dormice, cestode ova found in a captive individual produced a molecular match closely related to Hymenolepis microstoma and a previously unrecorded Rodentolepis species. To prevent putting at risk the free-living population, we recommended the continued treatment of dormice showing tapeworm infection before release. Our work demonstrates how molecular techniques can be used to inform reintroduction programmes, reduce risk from disease and increase chances of reintroduction success
Scanning electron microscopy and energy-dispersive x-ray spectroscopy (SEM-EDX) confirms shooting of a hen harrier (Circus cyaneus)
The hen harrier (Circus cyaneus) remains severely restricted as a breeding species in England despite sufficient habitat for over 300 breeding pairs. Human persecution is the main limiting factor and in the UK, there have been 45 confirmed incidents of shooting of hen harriers since records began (Royal Society for the Protection of Birds unpublished data). The authors report the pathological examination of a hen harrier, the detection of suspected ballistic fragments by radiograph and explain how scanning electron microscopy and energy-dispersive x-ray spectroscopy (SEM-EDX) was used to confirm (i) the composition of one ballistic remnant and (ii) that the remnant had been projected into and had damaged the bone. The authors report the use of post-analysis software to discriminate apparent anomalies produced by the proprietary SEM-EDX software package and discuss broader uses of SEM-EDX for wildlife crime investigation
Estimation of milk production in hair ewes by two methods of measurement
ABSTRACT
Objective. The objective of the current study was to compare two methods to estimate daily milk production in crossbred hair ewes. Materials and methods. Eight multiparous, crossbred (Pelibuey x Katahdin) lactating hair ewes were used in a completely randomized design with repeated measurements, for 56 days. Ewes were fed ad libitum with a diet based on concentrate. Milk production was estimated twice a week for each ewe by both methods, suckled-hand (SH) and weigh-suckle-weigh (WSW) method. Results. Milk production (p>0.05) means were 1031.9±95.6 and 1119.0±95.6 g/day/ewe for SH and WSW method, respectively. Conclusions. No significant differences (p>0.05) were found between methods for milk yield.
RESUMEN
Objetivo. El objetivo del presente trabajo fue comparar dos métodos para estimar la producción diaria de leche en ovejas de pelo cruzadas. Materiales y métodos. Se utilizaron ocho ovejas multíparas, cruzadas (Pelibuey x Katahdin) y lactantes, en un diseño completamente al azar, con medidas repetidas, durante 56 días. Las ovejas fueron alimentadas ad libitum con una dieta basada en concentrado. La producción de leche se estimó dos veces a la semana a cada oveja, mediante ambos métodos, el doble pesaje del cordero-ordeño manual de la ovejas (DPC-OMO) y el doble pesaje del cordero (DPC). Resultados. La producción de leche estimada (p>0.05) fue de 1031.9±95.6 y 1119.0±95.6 g/día/ovejas para el DPC-OMO y DPC, respectivamente. Conclusión. No se encontraron diferencias significativas (p>0.05) entre métodos de estimación de la producción de leche
Optimizacion del diseino de una red de distribucion de agua potable
En el presente reporte se present an los resultados obtenidos por el grupo de trabajo que estudio el problema de disenar de manera optima, una red de distribucion de agua potable. Esencialmente se discuten dos clases de estrategias. En primer lugar, aquellas cuya finalidad es reducir significativamente los recursos computacionales requeridos por los algoritmos im- plementados por el IMTA. Estos algoritmos son de caracter heuristico y generan una solucion factible que no es optima. En ciertos casos se sabe que las soluciones obtenidas por dichos algoritmos estan relativamente lejos del optima y no son aceptables desde el punto de vista del disenador. La segunda clase de estrategias propuestas, esta destinada precisamente a aliviar este problema. Se sugieren tecnicas originadas en optimizacion continua yen flujo en redes
PIN8 Estimation of the Number of Cases of Nosocomial Skin and Soft Tissue Infection in Adults Caused by Gram-Positive Bacteria in Public Hospitals in Mexico
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