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With the advancement of remote sensing, it is now possible to identify and characterize greenhouse gas emissions under deferment land uses. Given the above, this study aimed to characterize the spatial–temporal variability and the main factors controlling the average atmospheric CO2 column (Xco2) in the macroregion of Ribeirão Preto (MRP), São Paulo, a significant sugarcane producer in Brazil. We obtained remote sensing data from January 2015 to December 2018. The variables used were Xco2 and sun-induced fluorescence of chlorophyll (SIF) by NASA's Orbiting Carbon Observatory-2 satellite (OCO-2), relative humidity (RH), global radiation (Qg), and the average temperature at 2 m (T2m) by the NASA-POWER platform, and leaf area index (LAI) and evapotranspiration by Penman–Monteith (ET) by MODIS sensor. We evaluated the data in trimester's averages, where descriptive statistics, Pearson correlation and linear regression have been applied. The spatial distribution was made by the inverse distance weighted (IDW). The minimum (390.40 ± 0.41 ppm) and maximum (394.75 ± 0.34 ppm) mean of Xco2 was observed in the first quarter of 2015 and third quarter of 2017. The Xco2 obtained negative correlations with the SIF (−0.81), LAI (−0.81), RH (−0.74), ET (−0.84), and Qg (−0.51). Hotspots and coldspots of Xco2 tend to vary over the years. We conclude that the temporal variation of Xco2 above sugarcane areas in southern Brazil is well represented by a periodic function. Our results indicate photosynthesis and soil exposure after harvest are factors that could act as source and sink of CO2. [ABSTRACT FROM AUTHOR]

The Chikungunya virus (CHIKV) is an arbovirus transmitted to humans through mosquito bites and can cause a series of symptoms ranging from a benign febrile illness to severe neurological conditions. We report the identification of CHIKV in a serum sample from an elderly woman with febrile illness and severe arthralgia in Brazil. The occurrence was found of peripheral polyneuropathy affecting the upper and lower limbs evidenced by electroneuromyographic findings. The patient was treated with a corticoid associated with methotrexate, suggesting that the pathophysiological basis of the case in question may be related to an immune-mediated response by T cells and inflammatory cytokines. This finding reinforces the need to be aware of the emergence of neuroinfections related to CHIKV and effective diagnoses for the early detection of neurological alterations, favoring the clinical management of these patients. [ABSTRACT FROM AUTHOR]