Biomass burning (BB) in southern Africa is the largest emission source of CO and O3 precursors within Africa during the West African Monsoon (WAM) between June and August. The long range transport and chemical processing of such emissions thus has the potential to exert a dominant influence on the composition of the tropical troposphere over Equatorial Africa (EA) and the Tropical Atlantic Ocea...

Emissions of air pollutants in and around urban areas lead to negative health impacts on the population. To estimate these impacts, it is important to know the sources and transport mechanisms of the pollutants accurately. Mexico City has a large urban fleet in a topographically constrained basin leading to high levels of carbon monoxide (CO). Large point sources of sulfur dioxide (SO2) surroun...

[1] Quantifying the impacts of remote sources on individual air quality exceedances remains a significant challenge for air quality forecasting. One goal of the 2006 Second Texas Air Quality Study (TexAQS II) was to assess the impact of distant sources on air quality in east Texas. From 23 to 30 August 2006, retrievals of tropospheric carbon monoxide (CO) from NASA’s Atmospheric InfraRed Sounde...

Past studies have identified a variety of pathways by which carbon monoxide (CO) may be transported from the surface to the tropical upper troposphere (UT); however, the relative roles that these transport pathways play in determining the distribution and seasonality of CO in the tropical UT remain unclear. We have developed a method to automate the identification of two pathways (“local convec...

Sedimentation is one of the most important problems in harbors that results in considerable economic costs. Harbor planforms affects the flow pattern in the harbor basin and consequently, plays an important role in sediment transport and sedimentation. In the present study, a two dimensional depth-averaged hydrodynamic and sediment transport model has been developed to investigate the effect of...

A symmetry-breaking order-disorder transition of the Ising type is found in a nonequilibrium surface reaction model for CO oxidation incorporating superlattice ordering of adsorbed oxygen. We relate this transition to the percolation of superlattice domains of oxygen, and discuss the consequences for chemical diffusion of coadsorbed CO. The latter constitutes a new type of problem involving tra...

A mass spectrometer was used to simultaneously follow the time course of photosynthetic O(2) evolution and CO(2) depletion of the medium by cells of the cyanobacterium Synechococcus leopoliensis UTEX 625. Analysis of the data indicated that both CO(2) and HCO(3) (-) were simultaneously and continuously transported by the cells as a source of substrate for photosynthesis. Initiation of HCO(3) (-...

TREX is a physically-based, distributed model that simulates flash floods, sediment transport, and chemical transport and fate processes at the watershed scale. Basic processes in TREX include precipitation, interception, infiltration, surface runoff, and channel flow, erosion and deposition of upland soil and channel bed sediment, and chemical transport. TREX is readily coupled with standard G...

Vesicle transport is a central process to ensure protein and lipid distribution in eukaryotic cells. The current knowledge on the molecular components and mechanisms of this process is majorly based on studies in Saccharomyces cerevisiae and Arabidopsis thaliana, which revealed 240 different proteinaceous factors either experimentally proven or predicted to be involved in vesicle transport. In ...

The temperature response of net CO(2) assimilation rate (A), the rate of whole-chain electron transport, the activity and activation state of Rubisco, and the pool sizes of ribulose-1,5-bisphosphate (RuBP) and 3-phosphoglyceric acid (PGA) were assessed in sweet potato (Ipomoea batatas) grown under greenhouse conditions. Above the thermal optimum of photosynthesis, the activation state of Rubisc...