We show, from recent data obtained at specimen North Pacific stations, that the fossil fuel CO2 signal is strongly present in the upper 400 m, and that we may consider areal extrapolations from geochemical surveys to determine the magnitude of ocean fossil fuel CO2 uptake. The debate surrounding this topic is illustrated by contrasting reports which suggest, based upon atmospheric observations ...

Geochemical analysis and trace element distribution were performed on the marine sediments from short cores (30 to 50 cm) from the Middle (Jabuka and Palagruža pits, depth 230 m and 170 m, respectively) and South Adriatic Sea (depth 1030 m) and the Albanian offshore (50 m depth). The distribution of trace elements (As, Co, Cd, Cu Cr, Ni, Zn, Hg, and Pb) and major elements (Al, Ca and Mn) and mi...

In the hilly semi-arid region of central Argentina, where agricultural frontier expands at expense natural ecosystems, soil erosion is one most alarming environmental problems. Thus, obtaining knowledge about dynamics erosive processes and identifying hotspots constitutes a primary scientific objective. This investigation focused on estimating apportionments main sources sediments, mouth small ...

Context. Molecular line emission is a powerful probe of the physical conditions astrophysical objects but can be complex to model, and it often unclear which transitions would best targets for observers who wish constrain given parameter. Aims. We produce list molecular species gas history ignored, removing major modelling complexity. then determine these observe when attempting various paramet...

The Younger Dryas cold interval represents a time when much of the Northern Hemisphere cooled from approximately 12.9 to 11.5 kiloyears B.P. The cause of this event, which has long been viewed as the canonical example of abrupt climate change, was initially attributed to the routing of freshwater to the St. Lawrence River with an attendant reduction in Atlantic meridional overturning circulatio...

The role of solution chemistry (cation charge and concentration) and particle size on colloid transport was examined in an intact monolith of fractured shale saprolite (highly weathered rock). Recovery of the microsphere tracers consistently decreased with increasing ionic strength of either mono- (Na+) or divalent- (Ca2+) dominated solutions, but a much greater concentration of Na+ in the infl...

Concentrations and loads of total mercury and methylmercury were measured in streams draining abandoned mercury mines and in the proximity of geothermal discharge in the Cache Creek watershed of California during a 17-month period from January 2000 through May 2001. Rainfall and runoff were lower than long-term averages during the study period. The greatest loading of mercury and methylmercury ...

SKINNER, S. M., R. E. CLARK, N. BAKER AND R. A. SwPu3Y. Complete solution of the thwe-compartment model in steady state after single injection of radioactive tracer. Am. J. Physiol. Ig6(2): 2@-244. Ig5g.-solutions of a general, threecompartment model in a nonisotopic steady state are developed. By means of these solutions, the investigator may analyze a great variety of kinetic flow relationshi...

We perform a tracer counterpermeation (TCP) analysis for a stochastic model of diffusive transport through a narrow linear pore where passing of species within the pore is inhibited or even excluded (single-file diffusion). TCP involves differently labeled but otherwise identical particles from two decoupled infinite reservoirs adsorbing into opposite ends of the pore, and desorbing from either...

In recent years our knowledge of the formation, nutrition and metabolism of the cells of the blood has been greatly advanced by studies with the electron microscope, from tagging various nutrients and precursors with radioactive tracers, by advances in staining methods, by the use of specific enzymes to attack substances in particular regions of cells and of absorption-spectra techniques and va...