Procedure for emergetic assessment in urban river de-pollution.

Using emergetic indicators to evaluate complex processes such as the de-pollution of urban rivers aims to contribute to better use and preservation of the resources, besides the valuation of ecosystem services provided by the water body. Within this context, we conducted a bibliometric and systematic review that shows the lack of emergetic indicators in urban river de-pollution. Thus, this work aims to propose an emergetic assessment procedure to evaluate the de-pollution process of urban rivers that allows technicians, academics, and revitalization process managers of urban rivers to improve the monitoring and decision-making directly related to the process, concluding that an emergetic assessment procedure contributes to theory to create new scientific analyses applied to urban revitalization and nature preservation processes. The emergetic assessment procedure contributes to society by improving the disposal of public resources and the effective maintenance of urban rivers that provide ecosystem services to all stakeholders (residents, grantors, and sanitation companies). In practice, the use of the emergetic assessment contributes to the monitoring from the first stages of the clean-up process, demonstrating the sustainability of the process for the adequacy of resources and maintenance of the water body that shall be cleaned.

Relationship between analysis of laser speckle image and Knoop hardness on softening enamel.

BACKGROUND: In this study is presented the correlation between laser speckle images and enamel hardness loss. METHODS: In order to shift the enamel hardness, a dental demineralization model was applied to 32 samples of vestibular bovine teeth. After they were cleaned, cut and polished, the samples were divided into 4 groups and immersed in 30ml of a cola-based soft drink for 10, 20, 30 and 40min twice a day for 7 consecutive days with half the surface protected by two layers of nail polish. Each sample was analyzed by Knoop hardness and laser speckle imaging. RESULTS: Pearson's correlation analysis demonstrated that the laser speckle image technique presents a strong correlation with the hardness loss of the enamel (r=0.7085, p<0.0001). This finding is corroborated by Blend & Altman analysis, in which the data presented a constant behavior throughout the whole interval. For both analyses, more than 95% of the data is within the confidence interval, as expected. CONCLUSION: This work demonstrates, for the first time to our knowledge, an empirical model for correlating laser speckle images with the loss of tooth enamel hardness.