Vacuum ultraviolet/photofragmentation laser-induced fluorescence has been demonstrated to be a highly specific and sensitive method for the quantitative measurement of atmospheric ammonia (NH(3)). The fluorescence detected in this approach results from the two 193-nm photon photofragmentation step NH(3)?NH(2)? NH(b(1)Sigma(+)) followed by the excitation of the NH(b(1)Sigma(+)) NH(c(1)Pi) transi...

Ammonia-nitrogen #ux (NH -N"(14/17)NH ) was determined from six anaerobic swine waste storage and treatment lagoons (primary, secondary, and tertiary) using the dynamic chamber system. Measurements occurred during the fall of 1998 through the early spring of 1999, and each lagoon was examined for approximately one week. Analysis of #ux variation was made with respect to lagoon surface water tem...

OBJECTIVE To examine the association between selected unhealthy lifestyle factors, body mass index (BMI), and chronic conditions among individuals 50 years of age or older, by race/ethnicity. DESIGN We analyzed 2001-2004 data from the Behavioral Risk Factor Surveillance System (BRFSS), a state-based system of annual random-digit-dialed telephone surveys. PARTICIPANTS Noninstitutionalized US...

Global warming is increasing permanently, because the concentration of CO2 in the atmosphere is rising continuously. According to National Oceanographic and Atmospheric Administration, the concentration of CO2 in the atmosphere was 407 ppm in June 2016 and 413 ppm in April 2017 as a last record for now. If the effects of other greenhouse gases, such as CH4, N<su...

The specific activities of enzymes catalyzing the ammonium-dependent carbamyl phosphate synthesis (NH(3)-CPS) and the glutamine-dependent carbamyl phosphate synthesis (GLN-CPS) were increased during germination by approximately 5-and 1.7-fold respectively in the presence of 35 mm urea. The increase of NH(3)-CPS and GLN-CPS levels occurred immediately after the onset of germination and prior to ...

Site-directed mutagenesis of the aspartate receptor of Salmonella typhimurium (Tars) at serine 68, a residue located within the aspartate binding pocket and at the subunit interface, identified this residue as an allosteric switch in this receptor. Substitutions at this position can affect both the type and degree of binding cooperativity observed. Negative cooperativity is observed in the wild...

Primary production in the Northern San Francisco Estuary (SFE) has been declining despite heavy loading of anthropogenic nutrients. The inorganic nitrogen (N) loading comes primarily from municipal wastewater treatment plant (WTP) discharge as ammonium (NH(4)). This study investigated the consequences for river and estuarine phytoplankton of the daily discharge of 15 metric tons NH(4)-N into th...