Different kinds of particle gels were simulated using a process of random aggregation of hard spheres. The mean square displacement of Brownian spherical tracer particles through these rigid gels was monitored and the average diffusion coefficient, normalized with the free diffusion coefficient (D), was obtained. For each gel structure the effect of the gel volume fraction (φ) and size ratio of...

Measuring chemical tracers in tissues of marine predators provides insight into the prey consumed and the predator’s contaminant exposure. In this study, samples from Type C killer whales (Orcinus orca) biopsied in Antarctica were analyzed for chemical tracers (i.e., stable isotopes of carbon and nitrogen, fatty acids, and persistent organic pollutants [POPs]). Profiles of these individual trac...

We assessed the extent to which plants can acquire amino acids when supplied as single N-sources or when plants have access to a mixture of aminoand inorganic N sources. Because the uptake of different N-sources is temperaturedependent, the effects of temperature on amino-N uptake were also tested. Lolium perenne (perennial rye-grass) was grown hydroponically at 11 ∞ C or 21 ∞ C. Uptake of N wa...

Cancer cells do reprogram their energy metabolism to enable several functions, such as generation of biomass including membrane biosynthesis, and overcoming bioenergetic and redox stress. In this article, we review both established and evolving radioprobes developed in association with positron emission tomography (PET) to detect tumor cell metabolism and effect of treatment. Measurement of enh...

Prostate cancer is the second most common cancer in men worldwide, with a wide spectrum of biologic behavior ranging from indolent low-risk disease to highly aggressive castration-resistant prostate cancer. Conventional imaging with computed tomography, magnetic resonance imaging, and bone scintigraphy is limited for the detection of nodal disease and distant bone metastases. In addition, advan...

The intracellular activation of trypsinogen, which is both pH- and calcium-dependent, is an important early step in the development of acute pancreatitis. The cellular compartment in which trypsinogen activation occurs currently is unknown. We therefore investigated the site of intracellular trypsinogen activation by using an established cellular model of acute pancreatitis: supramaximal stimul...

Exfiltration from sewers poses negative environmental effects and health risks. Quantification of exfiltration is the first step towards solving these detrimental effects. QUEST/QUEST-C (Quantification of Exfiltration from Sewers with Artificial Tracers) methods were tested in this research. Two different tracers are used by these methods, in order to calculate mass balances rather than flow me...

Three cationic tracers, Sr2+, Co2+ and Cs+ were tested with a modified electromigration device by applying 2V, 3V 4V voltage gradients over an intact Grimsel granodiorite rock sample. An ideal plug-flow model advection-dispersion applied to analyze the breakthrough curves. Matrix characterization C-14-PMMA autoradiography scanning electron microscopy showed that in centimeter scale of rock, int...