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In the Amazon basin, particles containing mixed sodium salts are routinely observed and are attributed to marine aerosols transported from the Atlantic Ocean. Using chemical imaging analysis, we show that, during the wet season, fungal spores emitted by the forest biosphere contribute at least 30% (by number) to sodium salt particles in the central Amazon basin. Hydration experiments indicate that sodium content in fungal spores governs their growth factors. Modeling results suggest that fungal spores account for ~69% (31-95%) of the total sodium mass during the wet season and that their fractional contribution increases during nighttime. Contrary to common assumptions that sodium-containing aerosols originate primarily from marine sources, our results suggest that locally-emitted fungal spores contribute substantially to the number and mass of coarse particles containing sodium. Hence, their role in cloud formation and contribution to salt cycles and the terrestrial ecosystem in the Amazon basin warrant further consideration.

Amazonia hosts the Earth's largest tropical forests and has been shown to be an important carbon sink over recent decades.sup.1-3. This carbon sink seems to be in decline, however, as a result of factors such as deforestation and climate change.sup.1-3. Here we investigate Amazonia's carbon budget and the main drivers responsible for its change into a carbon source. We performed 590 aircraft vertical profiling measurements of lower-tropospheric concentrations of carbon dioxide and carbon monoxide at four sites in Amazonia from 2010 to 2018.sup.4. We find that total carbon emissions are greater in eastern Amazonia than in the western part, mostly as a result of spatial differences in carbon-monoxide-derived fire emissions. Southeastern Amazonia, in particular, acts as a net carbon source (total carbon flux minus fire emissions) to the atmosphere. Over the past 40 years, eastern Amazonia has been subjected to more deforestation, warming and moisture stress than the western part, especially during the dry season, with the southeast experiencing the strongest trends.sup.5-9. We explore the effect of climate change and deforestation trends on carbon emissions at our study sites, and find that the intensification of the dry season and an increase in deforestation seem to promote ecosystem stress, increase in fire occurrence, and higher carbon emissions in the eastern Amazon. This is in line with recent studies that indicate an increase in tree mortality and a reduction in photosynthesis as a result of climatic changes across Amazonia.sup.1,10. Aircraft observations of atmospheric carbon dioxide and monoxide concentrations in Brazil show higher carbon emissions in eastern Amazonia than in the western part, which are linked to increased ecosystem stress and fire occurrence., Author(s): Luciana V. Gatti [sup.1] [sup.2] , Luana S. Basso [sup.1] , John B. Miller [sup.3] , Manuel Gloor [sup.4] , Lucas Gatti Domingues [sup.1] [sup.2] [sup.5] , Henrique L. [...]

Soils are a major source of nitrogen oxides, which in the atmosphere help govern its oxidative capacity. Thus the response of soil nitric oxide (NO) emissions to forcings such as warming or forest loss has a meaningful impact on global atmospheric chemistry. We find that the soil emission rate of NO in Amazonia from a common inventory is biased low by at least an order of magnitude in comparison to tower‐based observations. Accounting for this regional bias decreases the modeled global methane lifetime by 1.4%–2.6%. In comparison, a fully deforested Amazonia, representing a 37% decrease in global emissions of isoprene, decreases methane lifetime by at most 4.6%, highlighting the sensitive response of oxidation rates to changes in emissions of NO compared to those of terpenes. Our results demonstrate that improving our understanding of soil NO emissions will yield a more accurate representation of atmospheric oxidative capacity. Plain Language Summary: Soils emit a gas called nitric oxide (NO). The amount of NO emitted from soils in tropical forests is not well known, but has been assumed to be small. We simulated how different amounts of NO emissions from soils in the Amazon impacted atmospheric chemistry. By comparing our modeled results to observations we found that NO emissions from soils in the Amazon may be between 10 and 20 times larger than the current default assumption. This matters because NO has a strong influence on the rate at which methane and other gasses are removed from the atmosphere. Therefore soil NO emissions end up impacting how long methane can last in the atmosphere, and that would have additional climate impacts. Even though soil NO emissions are smaller than other sources of NO emissions globally, we find that the amount of NO emitted in the Amazon matters a lot for how long methane can last in the atmosphere. Our results demonstrate that improving estimates of soil NO emissions is going to be necessary for making accurate estimates of how long methane and other reactive species will stay in the atmosphere. Key Points: Soil emission rates of NO in common inventories may be between 10× and 20× too low over the Amazon basinHigher soil NO over the Amazon basin alters the oxidative capacity of the atmosphere and decreases global methane lifetime by 1.4%–2.6%Global methane lifetime is more sensitive to Amazon soil NO fluxes than to the loss of terpene fluxes from total deforestation of the Amazon [ABSTRACT FROM AUTHOR]

Background and Aims: To evaluate the effect of lifestyle modification by adopting a DASH diet, with and without physical activity guidance, on blood pressure, glycemic control, lipid profile, weight, and body composition in older patients with type 2 diabetes mellitus (T2DM) and hypertension. Methods and Results: For this randomized clinical trial, we recruited patients aged 60 years or older with T2DM and uncontrolled hypertension. One group (DASH) received only DASH dietary guidance, while the other group (DASHPED) received dietary guidance and encouragement to walk with a pedometer. Outcomes of interest were (1) blood pressure, (2) physical activity, (3) weight, body mass index (BMI), and body composition, and (4) biochemical variables. Measurements were taken at baseline and 16 weeks after the intervention. We included 35 patients in the analysis. At the end of the study, the DASHPED group had an mean increase in physical activity of 1721 steps/day. Both groups displayed significantly reduced weight, BMI, and waking diastolic pressures on ambulatory blood pressure monitoring after the intervention. A trend of reduced sleeping diastolic pressure was found in the DASHPED group. Changes in weight, BMI, muscle mass, body fat, waist-hip ratio, glycemic control, lipid profile, and insulin sensitivity did not differ between the groups. Conclusion: There was no difference in outcomes between the group that only dieted and the group that also performed increased physical activity, despite a significant increase in exercise. This reinforces the importance of dietary changes in immediate blood pressure control. [ABSTRACT FROM AUTHOR]

This work aimed to evaluate the effect of the addition of fine solids with different mineralogical compositions on the physical properties of olefinic fluids used in pre-salt wells. The fluids were added with 5% of each mineral (clay, silica, carbonate or halite) separately and characterized by rheological properties, filtrate volume and separated volume. According to the results, bentonite act as a physical barrier, improving aged fluid behavior, leading to a 66.67% decrease in separated volume. On the other hand, halite has presented a negative effect on fluid properties and resulted in an increase of 88.89% in separated volume. [ABSTRACT FROM AUTHOR]

The Canopy Horizontal Array Turbulence Study (CHATS) experimental study was conducted at a Cilker Orchards's walnut blocks in Dixon, California, before and after leaves emerged, to help improve understanding, simulation capabilities, and modeling of coupled vegetation-atmosphere-land surface interactions. The campaign took place over 12 weeks in the spring of 2007 and was broken into three 4-week phases. Canopy-induced mechanical and thermodynamical vertical variation of turbulence transport characteristics and the linkages between canopy-scale motions and the larger scale planetary boundary layer (PBL) turbulence were measured. The observations focused on measurements characterizing stratification influences on the spatial structure of canopy-induced turbulence, the trace gas source/sink distribution associated with vegetation, and the overall impact of canopy-induced processes on trace gas transport.