[1] The Deep Ocean Raman In Situ Spectrometer (DORISS) instrument was deployed at the Sea Cliff Hydrothermal Field and Hydrate Ridge in July 2004. The first in situ Raman spectra of hydrothermal minerals, fluids, and bacterial mats were obtained. These spectra were analyzed and compared to laboratory Raman measurements of standards and samples collected from the site. Spectra of vent fluid ( 29...

Since deep-sea hydrothermal vent fluids are enriched with toxic metals, it was hypothesized that (i) the biota in the vicinity of a vent is adapted to life in the presence of toxic metals and (ii) metal toxicity is modulated by the steep physical-chemical gradients that occur when anoxic, hot fluids are mixed with cold oxygenated seawater. We collected bacterial biomass at different distances f...

Hydrothermal vent ecosystems support diverse life forms, many of which rely on symbiotic associations to perform functions integral to survival in these extreme physicochemical environments. Epsilonproteobacteria, found free-living and in intimate associations with vent invertebrates, are the predominant vent-associated microorganisms. The vent-associated polychaete worm, Alvinella pompejana, i...

This study examined the effects of human pregnancy on heart rate variability (HRV), spontaneous baroreflex (SBR) sensitivity, and plasma catecholamines at rest and during exercise. Subjects were 14 healthy, physically active pregnant women (PG; mean gestational age = 33.9 +/- 1.0 wk). Results were compared with an age-matched nonpregnant control group (NPG; n = 14) with similar characteristics....

The shrimp Mirocaris fortunata is a hydrothermal vent species that is found at most vent-sites along the Mid-Atlantic Ridge. This endemic species is found across a hydrothermal gradient, with thermal conditions ranging from 2-9 degrees C in ambient seawater to fairly warm values of about 25 degrees C. We performed in vivo experiments on M. fortunata specimens originating from different sites an...

Volcanic plumes resulting from explosive volcanic eruptions present a variety of hazards depending on their behavior. Buoyant plumes heat and entrain enough of the surrounding air to rise high into the atmosphere, disrupting air traffic and causing regional ash fall. Alternatively, collapsed plumes produce dangerous fast-moving lateral flows of hot ash and gas. The transition between these beha...

The Champagne Hot Springs (CHS) shallow submarine hydrothermal system is located along the submerged flank of the Plat Pays volcanic system on the southwest section of the island of Dominica, Lesser Antilles. We have conducted a detailed geochemical study of the hydrothermal system, with the objectives to investigate the source of the hydrothermal fluids and gases, their effect on sediment and ...

An improved method of sample injection was demonstrated for introducing ultra-low volume liquid on a microfabricated device. In our previous study, a pressure-driven injection method has been introduced and was applied to on-chip electrophoresis. In this study, the need for control of the air vent, which was indispensable for sample injection in the previous study, was completely eliminated, fa...