Concentrations of total mercury and methyl mercury were determined in sediment and fish collected from estuarine waters of Florida to understand their distribution and partitioning. Total mercury concentrations in sediments ranged from 1 to 219 ng/g dry wt. Methyl mercury accounted for, on average, 0.77% of total mercury in sediment. Methyl mercury concentrations were not correlated with total ...

Anisotropic wet etching is a most widely employed for the fabrication of MEMS/NEMS structures using silicon bulk micromachining. The use of Si{110} in MEMS is inevitable when a microstructure with vertical sidewall is to be fabricated using wet anisotropic etching. In most commonly employed etchants (i.e. TMAH and KOH), potassium hydroxide (KOH) exhibits higher etch rate and provides improved a...

The metabolism of the cytotoxic lipid peroxidation product 4-hydroxynonenal was studied in perfused rat kidney. We investigated the total capacity of the rat kidney to metabolize 4-hydroxynonenal (HNE) and quantified the metabolites in the venous effluents as well as in the excreted urine. A rapid utilization of HNE was demonstrated, due to its immediate reactions with cellular compounds and it...

To elucidate the pathophysiological role of the hydroxyl radical (.OH) during the postischemic reperfusion of the heart, we measured the .OH product in the coronary effluent from isolated perfused rat heart during a 30-minute reperfusion period after various ischemic intervals of 5, 10, 15, 20, 30, and 60 minutes. Salicylic acid was used as the probe for .OH, and its derivative, 2,5-dihydroxybe...

To determine whether the effects of fatty acids on the diabetic heart during ischemia involve altered glycolytic ATP and proton production, we measured energetics and intracellular pH (pH(i)) by using (31)P NMR spectroscopy plus [2-(3)H]glucose uptake in isolated rat hearts. Hearts from 7-wk streptozotocin diabetic and control rats, perfused with buffer containing 11 mM glucose, with or without...

Leptin acutely increases fatty acid (FA) oxidation and triacylglycerol (TG) hydrolysis, and decreases TG esterification in oxidative rodent muscle. However, the effects of chronic leptin administration on FA metabolism in skeletal muscle have not been examined. We hypothesized that chronic leptin treatment would enhance TG hydrolysis as well as the capacity to oxidize FA in soleus (SOL) muscle....

The concentration of diacylglycerols in rat liver was measured by a newly developed procedure that entailed a) freeze-clamping of the liver in situ, b) lipid extraction with dimyristoylglycerol as an internal standard, c) thin-layer chromatography, and d) gas-liquid chromatography. Molecular species of diacylglycerol and total diacylglycerols were quantified. The average level of diacylglycerol...

Organohalogen compounds, the pesticides aldrin, dieldrin, endrin, hexachlorobenzene, mirex, Sigmachlordanes, SigmaDDTs, Sigmaheptachlors, Sigmatoxaphenes, and the industrial chemicals SigmaPCBs and SigmaPBDEs, as well as total dioxin-like equivalents (TEQH4IIE-luc), were measured in eggs of two Ardeid species, the little egret (Egretta garzetta) and black-crowned night heron (Nycticorax nyctico...

supported vanadia catalyst was successfully synthesized using wet impregnation of gamma-alumina to study propane oxidative dehydrogenation (pod). the prepared catalysts were characterized with xrd, bet, and tpr tests. in a broad temperature range (340 to 630°c), effects of vanadia loading (2.7, 5.4, and 9 wt%) and propane to oxygen ratio (3/1 to 1/3) were investigated on propane conversion as w...

There are basically two ways to etch silicon: dry and wet chemical etching. In micromachining, the control of the shape of the structure is accomplished by anisotropic etching through mask openings. The anisotropy of wet chemical etching is related to the crystal structure of silicon, while that of dry etching stems from the momentum of ions impinging the substrate. The latter gives us much mor...