RESUMEN
How insects promote crop pollination remains poorly understood in terms of the contribution of functional trait differences between species. We used meta-analyses to test for correlations between community abundance, species richness and functional trait metrics with oilseed rape yield, a globally important crop. While overall abundance is consistently important in predicting yield, functional divergence between species traits also showed a positive correlation. This result supports the complementarity hypothesis that pollination function is maintained by non-overlapping trait distributions. In artificially constructed communities (mesocosms), species richness is positively correlated with yield, although this effect is not seen under field conditions. As traits of the dominant species do not predict yield above that attributed to the effect of abundance alone, we find no evidence in support of the mass ratio hypothesis. Management practices increasing not just pollinator abundance, but also functional divergence, could benefit oilseed rape agriculture.
Asunto(s)
Biodiversidad , Brassica rapa , Producción de Cultivos , Productos Agrícolas , Insectos , Polinización , AnimalesRESUMEN
A method to determine the optimal replacement time for dye affinity adsorbents used in protein purification processes that are subjected to severe regeneration conditions has been developed. To demonstrate the utility of the method, an experimental fixed-bed decay model was employed to determine the optimum number of cycles for the adsorbent replacement. This number is a function of the column regeneration frequency and of the capital and operation costs. The implications of the results on the design and operation of dye-ligand chromatographic processes are discussed.
Asunto(s)
Proteínas/aislamiento & purificación , Adsorción , Cromatografía , Colorantes , Factores de TiempoRESUMEN
Many procedures have been described for the resection of plantar calcaneal spurs as treatment of heel spur syndrome and chronic plantar fasciitis. Most of these techniques involve a medial incision of between 2 and 6 cm for adequate exposure of the calcaneal spur. This article describes a new technique for resecting a calcaneal spur with a smaller medial incision using the holmium:yttrium-aluminum-garnet (Ho:YAG) laser. This laser permits adequate resection of a plantar calcaneal spur as well as coagulation of the bone and surrounding tissues. This minimally invasive procedure has been used with good results over the past year by the senior author (W.K.S.) for the resection of calcaneal spurs.
Asunto(s)
Calcáneo/cirugía , Exostosis/cirugía , Terapia por Láser/métodos , Femenino , Humanos , Persona de Mediana Edad , Procedimientos Quirúrgicos Mínimamente InvasivosRESUMEN
An appropriate health technology to facilitate child growth and development in a rural area is presented and documented. Because mother's adequate behavior related to child's care does not produce immediate behavioral or physical changes it is necessary to create a long term social system of consequences. This was achieved joining a longitudinal measurement system with a program to train mothers to identify and deal with health and development issues. During four years, data were collected on weight-length development and morbidity twice a year and simultaneously skills were taught to diagnose treatment and prevent growth and development problems. After the third session child development and anthropometry data became the base of a system to assess maternal behavior, providing consequences for links in the behavior chains associated with child care. This system made organization and participation of the community in primary health care programs more likely, which implied a better score in each child growth and development chart.
Asunto(s)
Discapacidades del Desarrollo/prevención & control , Trastornos del Crecimiento/prevención & control , Educación en Salud/métodos , Conducta Materna , Vigilancia de la Población/métodos , Adulto , Estatura , Niño , Fenómenos Fisiológicos Nutricionales Infantiles , Crianza del Niño , Preescolar , Discapacidades del Desarrollo/epidemiología , Femenino , Control de Formularios y Registros , Trastornos del Crecimiento/epidemiología , Humanos , Lactante , Fenómenos Fisiológicos Nutricionales del Lactante , Recién Nacido , Masculino , México/epidemiología , Refuerzo en Psicología , Población Rural , Aumento de Peso , Recursos HumanosRESUMEN
The purpose of the study was to evaluate the impact of a school breakfast program in Sonora, Mexico. The study was conducted in four counties classified as extremely poor. Three hundred children from twelve schools pertaining to three counties under research received a school breakfast; one hundred and fifty children from four schools pertaining to a fourth county did not received school breakfast. Children were four to six years old. Attention, memory and cognition tests were applied before and after the program. Results showed an improvement for those groups receiving the breakfast program, specially on response speed and behavior executions. Group without breakfast showed better results on the pre-test, nevertheless, on the post-test, performances in both groups appear the same. At the beginning of school courses any county was different, but speed in selection and running show significatives differences for the schools. The program shows similar results on response speed, no matter social condition, nevertheless, program differentially affects the number of correct behavior executions on stimulus selection and reproduction. The breakfast program benefit children, but its effects are differentially distributed improving behavioral, repertories depending of children's group vulnerability.