Municipality-Level Characteristics Associated with Very Low to Good Quality of Water Fluoridation in São Paulo State, Brazil, in 2015.

INTRODUCTION: Community water fluoridation (CWF) is a measure of recognized importance due to its effectiveness in preventing tooth decay at the population level. However, for the maximum benefit to be achieved, the high-quality standard of CWF must be maintained over time. OBJECTIVE: To analyze the municipality-level characteristics associated with quality of water fluoridation in São Paulo state, Brazil. METHODS: An ecological study was performed using official data sources on fluoride concentration surveillance in 2015. The outcome was municipalities that have not met the quality standard, identified as those with less than 80% of water samples within the optimal level for caries prevention. The independent variables were municipality-level indicators related to demographics, economics, and sanitation characteristics. Crude and adjusted prevalence ratios were estimated using Poisson regression with robust variance. RESULTS: In total, 43.4% municipalities exhibited the outcome. Adjusted by Gini index, the prevalence ratio was 32% higher in municipalities with lower annual gross domestic product per capita. Adjusted by social responsibility index and earlier variables, the prevalence was higher in the municipalities with higher per capita expenditure on sanitation and health surveillance, where the urban population rate was lower, and with a human development index ≤0.761. Adjusted by earlier variables, the prevalence ratio was twice and 3.5 times higher for municipalities, respectively, with per capita income less than or equal to US$574 and where the type of sanitation utility was municipal and private; 50% higher in those with less than 100,000 habitants; and 20% higher in those with a chlorine concentration nonconformity rate above 0.82%. CONCLUSIONS: To ensure high quality of CWF, additional management measures should be implemented in municipalities with less than 100,000 habitants, a higher chlorine concentration nonconformity rate, a lower per capita income, and where the type of sanitation utility was municipal or private. KNOWLEDGE TRANSFER STATEMENT: The study showed that the quality of fluoridation was associated with municipality-level characteristics. The findings can be used by policy makers to identify and support municipalities that will need to improve fluoridation quality if they are to reach oral health goals.

Quantum conductance-temperature phase diagram of granular superconductor K x Fe2-ySe2.

It is now well established that the microstructure of Fe-based chalcogenide K x Fe2-ySe2 consists of, at least, a minor (~15 percent), nano-sized, superconducting K s Fe2Se2 phase and a major (~85 percent) insulating antiferromagnetic K2Fe4Se5 matrix. Other intercalated A1-xFe2-ySe2 (A = Li, Na, Ba, Sr, Ca, Yb, Eu, ammonia, amide, pyridine, ethylenediamine etc.) manifest a similar microstructure. On subjecting each of these systems to a varying control parameter (e.g. heat treatment, concentration x,y, or pressure p), one obtains an exotic normal-state and superconducting phase diagram. With the objective of rationalizing the properties of such a diagram, we envisage a system consisting of nanosized superconducting granules which are embedded within an insulating continuum. Then, based on the standard granular superconductor model, an induced variation in size, distribution, separation and Fe-content of the superconducting granules can be expressed in terms of model parameters (e.g. tunneling conductance, g, Coulomb charging energy, E c , superconducting gap of single granule, Δ, and Josephson energy J = πΔg/2). We show, with illustration from experiments, that this granular scenario explains satisfactorily the evolution of normal-state and superconducting properties (best visualized on a [Formula: see text] phase diagram) of A x Fe2-ySe2 when any of x, y, p, or heat treatment is varied.

Stomach content analyses of Simulium perflavum Roubaud 1906 (Diptera: Simuliidae) larvae from streams in Central Amazônia, Brazil.

Stomach contents of Simulium perflavum Roubaud larvae were analyzed and compared with plankton and periphyton collected in five streams, in Central Amazonia (Manaus and Presidente Figueiredo counties), in Sep./Oct.1996 (dry season) and Feb./Mar. 1997 (rainy season). A total of 1,400 last-instar larvae were dissected; the stomach contents were analyzed using different methods: fresh and after oxidation. A total of 87 taxa (algae, diatoms and rotifers) were found in the stomach contents. In each stream, qualitative samples of plankton and periphyton were collected; these were mounted between slides and cover slips. A total of 94 taxa of plankton and 54 taxa of periphyton were collected. One species of Rotifera was present in the stomach contents, plankton and periphyton. Cluster analysis based on species composition of the organisms present in the stomach contents grouped the streams into two major groups, each belonging to a different drainage area. Correlations based on presence/absence of species of microalgae in the stomach contents, plankton and periphyton indicated significant associations (p<0.05) between stomach contents and plankton and between plankton and periphyton (z test); the Sorensen coefficient and cluster analysis corroborate the same associations.

Rotavirus strains bearing genotype G9 or P[9] recovered from Brazilian children with diarrhea from 1997 to 1999.

Human rotavirus strains belonging to genotype G9 or P[9] were detected in a collection of stool specimens from children with diarrhea in two cities of the state of Rio de Janeiro, Brazil, between March 1997 and December 1999. G9 strains were first detected in April 1997 and remained prevalent until the end of the study, at a frequency of 15.9% (n = 157). A high percentage of VP7 nucleotide (99.0 to 99.5%) and deduced amino acid identity (98.6 to 99.1%) was found between three randomly selected Brazilian G9 strains and the American G9 strain US1205. A novel G9:P[4] genotype combination was detected in addition to G9:P[8] and G9:P[6], demonstrating that this G genotype may undergo constant genetic reassortment in nature. The P[9] rotavirus strains constituted 10.2%, the majority of which were detected between April and July 1997. The RNA electrophoretic migration pattern of the G3:P[9] strains resembled that of AU-1 virus (G3:P3[9]), suggesting a genetic similarity between the Brazilian G3:P[9] strains and the Japanese virus, which is similar to a feline rotavirus genetically.