we performed molecular dynamics simulations using the coarse-grained model to study the freezing behavior of pure water and 14% water-salt mixture in a wide range of temperatures for a very long time around 50 nanoseconds. for the salty water, an interface in nanoscale was used. for both systems, the freezing behavior of water molecules was studied using some qualities such as density, total en...

A critical knowledge gap in our understanding of the interaction of sound with the ocean bottom is the frequency dependence of sound speed and attenuation in marine sediments. The long term goals of this research project are related to the investigation of dispersion of sound speed and attenuation at low frequencies (< 2 kHz) in different types of marine sediments. The research involves develop...

Radiocarbon analyses and stable isotope measurements are presented foro recent cores of banded corals from the Florida Straits. These values provide a record of variations in the ratio of carbon-14 to carbon-12 in the dissolved inorganic carbon in the surface waters of the Gulf Stream from A.D. 1642 to 1800. An increase in the carbon-14/carbon-12 ratio of 7 per mil for coral growth during the e...

ESBL-producing bacteria are present in wildlife and the environment might serve as a resistance reservoir. Wild gulls have been described as frequent carriers of ESBL-producing E. coli strains with genotypic characteristics similar to strains found in humans. Therefore, potential dissemination of antibiotic resistance genes and bacteria between the human population and wildlife need to be furth...

Distribution of salinity, dissolved oxygen, nitrate, phosphate, and silicate are presented for the western Gulf of Mexico in 1978. Plots of chemical concentration versus potential density are used to identify the presence of gulf water, tropical Atlantic central water, Antarctic intermediate water, Caribbean midwater, and upper North Atlantic deep water within the upper 1600 m of the western Gu...

Annual tritium exposures were reconstructed using tree cores from Pinus jeffreyi and Eucalyptus globulus near a tritiated water vapor release stack. Both tritium (3H) and carbon-14 (14C) from the wood were measured from milligram samples using accelerator mass spectrometry. Because the annual nature of the eucalyptus tree rings was in doubt, 14C measurements provided growth rates used to estima...