abstract   background: the compounds which contain nitrogen entering the environment can cause some problems, such as eutrophication for water resources and potential risk for human health because of methemoglobinemia and cancer. biological techniques are effective in removing nitrate. the aim of this study was to remove nitrate from groundwater using denitrification. the main objectives of thi...

the purpose of this study was to examine whether the frequency of breakfast consumption was related to academic performance in healthy korean adolescents.we analyzed data from the seventh korea youth risk behavior web-based survey conducted in 2011, in which 75,643 adolescents from school grades 7-12 participated. we assessed the association between the frequency of breakfast consumption (per w...

Nitrate and nitrite can be organic or inorganic chemicals depending on their chemical structures. This profile pertains to inorganic nitrate and nitrite, specifically the nitrate anion and the nitrite anion. Nitrate and nitrite occur naturally in the environment as part of the nitrogen cycle, and are produced both endogenously and exogenously. Ammonia-oxidizing bacteria convert ammonia into nit...

Chlorella pyrenoidosa was grown in a continuous-flow chemostat under nitrogen-limited conditions. The population density tended to oscillate very significantly. Net specific growth rate was only approximately a hyperbolic function of nitrate concentration in the chemostat. The best estimate of the half-saturation constant for nitrate is 6 mug of nitrogen per liter and it is unlikely that the va...

Background: Qual2k is a stream water quality model and was used to evaluate the water quality of the Kine-Vars River and assess the response of the river to nutrient management strategies. Methods: For that purpose, 7 sample stations were selected and surface water samples were collected in the winter and summer of 2012 and were analyzed for temperature, dissolved oxygen, biological oxygen dem...

A large reservoir of bioavailable nitrogen (up to approximately 10(4) kilograms of nitrogen per hectare, as nitrate) has been previously overlooked in studies of global nitrogen distribution. The reservoir has been accumulating in subsoil zones of arid regions throughout the Holocene. Consideration of the subsoil reservoir raises estimates of vadose-zone nitrogen inventories by 14 to 71% for wa...

Abstract The aim of this study is to determine the Caracosh (Al-Hamdannia district) groundwater water quality index (CCME WQI). This was calculated by taking samples and putting them into a thorough physicochemical examination. For calculating WQI, following 9 parameters have been considered: pH, TDS, T. Alkalinity, hardness, Ca, Mg, Chloride, Sulphate Nitrate. WQI for these ranges from 25.19 9...

Several lines of evidence implicate ammonium as an important factor in the growth and development of cotton (Gossypium hirsutum L.) ovules cultured in vitro. For example, ovules cultured at 28 C require indoleacetic acid (IAA) and either ammonium or gibberellic acid (GA(3)) in the medium for fiber development, whereas ovules cultured at 34 C require only IAA. Because of this effect of ammonium ...