RESUMO
BACKGROUND: Owing to the difficulty in reaching targets during pesticide applications on guava trees, it is important to evaluate new technologies that may improve pest management. In electrostatic spraying, an electric force is added to the droplets to control their movements such that they are efficiently directed to the target. The present study evaluated the performance of electrostatic and non-electrostatic spraying in the control of the guava psyllid, the deposition of the spray mixture on the leaves and the losses to the soil. RESULTS: The deposition of the spray mixture was up to 2 times greater when using electrostatic spraying in comparison with non-electrostatic application. The losses of the spray mixture to the soil were up to 4 times smaller with the electrostatic spraying. Electrostatic spraying had better control of the psyllid. CONCLUSION: It was possible to reduce the volume rate of application with electrostatic spraying without adversely affecting the control of the guava psyllid. © 2016 Society of Chemical Industry.
Assuntos
Hemípteros , Controle de Insetos/instrumentação , Inseticidas , Psidium , Animais , Neonicotinoides , Nitrocompostos , Resíduos de Praguicidas , Folhas de Planta , ÁrvoresRESUMO
OBJECTIVE: To evaluate if mid-upper arm circumference (MUAC) can be used for obesity screening in preschool children. METHODS: 1,090 children aged from 12 to 59.99 months were studied. Personal information, weight, height and MUAC were obtained. Sensitivity and specificity to detect obese children were calculated for MUAC to age and MUAC to height z scores. Obesity was defined as weight to height z score >2. RESULTS: 6.6% of the children had a weight to height z score >2. The best association between sensitivity (76.5%) and specificity (77.9%) to detect obese children for MUAC to age was obtained with a z score of 0.7. In terms of MUAC to height, the best association between sensitivity (79.4%) and specificity (77.6%) to detect obese children was obtained with a 0.6 score. CONCLUSIONS: MUAC to height z score was not advantageous for obesity screening when compared to MUAC to age z score. MUAC to age z score seems to be an adequate alternative method for obesity screening in preschool children.