Impact of extreme wildfires from the Brazilian Forests and sugarcane burning on the air quality of the biggest megacity on South America.

Recently, extreme wildfires have damaged important ecosystems worldwide and have affected urban areas miles away due to long-range transport of smoke plumes. We performed a comprehensive analysis to clarify how smoke plumes from Pantanal and Amazon forests wildfires and sugarcane harvest burning also from interior of the state of São Paulo (ISSP) were transported and injected into the atmosphere of the Metropolitan Area of São Paulo (MASP), where they worsened air quality and increased greenhouse gas (GHG) levels. To classify event days, multiple biomass burning fingerprints as carbon isotopes, Lidar ratio and specific compounds ratios were combined with back trajectories modeling. During smoke plume event days in the MASP fine particulate matter concentrations exceeded the WHO standard (>25 µg m-3), at 99 % of the air quality monitoring stations, and peak CO2 excess were 100 % to 1178 % higher than non-event days. We demonstrated how external pollution events such as wildfires pose an additional challenge for cities, regarding public health threats associated to air quality, and reinforces the importance of GHG monitoring networks to track local and remote GHG emissions and sources in urban areas.

Active Commuting by Bicycle: Results of an Educational Intervention Study.

OBJECTIVE: The objective of this study was to assess the effectiveness of an educational intervention on active commuting by bicycle. METHODS: An intervention study with workers from a metallurgical industry in Santa Catarina state, Brazil was carried out in 2011. A total of 464 individuals were placed in the intervention group (IG) and 468 in the control group (CG). The intervention consisted of strategies based on the transtheoretical model and stages of behavior change. The intervention group took part in activities for 6 months, including 23 meetings. The statistical analysis included intergroup comparison (IG × CG) at baseline and after the intervention. Intragroup analysis was performed 6 months after the intervention. Student's t-test, chi-square, and McNemar tests were used to analyze the data. RESULTS: Of the original total, 876 individuals (94%) participated in the study. The proportion of participants that used bicycles to commute to work (IG) increased significantly from baseline (45.3%) to the final interventional period (47.5%). No difference was found between the CG and the IG group after the interventional period. CONCLUSION: We suggest taking these findings into consideration in further studies to understand better the role of educational intervention on active commuting by bicycle.

[Increased atrial refractoriness: an explanation for the rarity of atrial arrhythmias in chronic cor pulmonale (author's transl)]. / L'aumento della refrattarieta' atriale: una spiegazione della rarita' delle aritmie atriali nel cuore polmonare cronico

Right atrial monophasic action potential was recorded using a suction electrode catheter in 20 patients with chronic cor pulmonale. The duration of right atrial monophasic action potential was recorded using suction electrode catheter in 20 patients with chronic corpulmonale. The duration of right atrial monophasic action potential was 397 +/- 17 msec, longer than the normal value of 325 +/- 37 msec found in 30 normal subjects. The conclusion of our work is that the long right atrial monophasic action potential duration may explain the sinus rhythm stability and the rarity of atrial arrhythmias in chronic cor pulmonale.