This study was conducted to determine soil properties that correlate with the arbuscular mycorrhizal fungal (AMF) spore numbers in semiarid calcareous soils of Hamadan province in northwestern of Iran. Soil samples from six sites managed differently were collected from a 0 to 30 cm depth. The results showed that land use and management systems had a significant effect on AMF spore number in soi...

The demand for energy has been promptly increasing due to rapid growing world population and increased growth of industries. In the pursuit of renewable energy production, the anaerobic digestion of organic wastes was a proved technology that is shaping up to be the one of the reliable source of alternate energy. Even though the anaerobic digestion is an effective method of renewable energy pro...

In 1912 Hasselbalch, with Lundsgaard and Gammeltoft (6, 7), described a lowering of the alveolar carbon dioxide and of the carbon dioxide-combining power of the blood in the later months of normal pregnancy. These changes have been abundantly confirmed by others and found to appear early in the course of pregnancy. These findings together with an increased ammonia to total nitrogen ratio in the...

During phytoplankton growth a fraction of dissolved inorganic carbon (DIC) assimilated by phytoplankton is exuded in the form of dissolved organic carbon (DOC), which can be transformed into extracellular particulate organic carbon (POC). A major fraction of extracellular POC is associated with carbon of transparent exopolymer particles (TEP; carbon content = TEPC) that form from dissolved poly...

L-arginine, an amino acid with a growing range of applications within the pharmaceutical, cosmetic, food, and agricultural industries, can be produced by microbial fermentation. Although it is the most nitrogen-rich amino acid, reports on the nitrogen supply for its fermentation are scarce. In this study, the nitrogen supply for the production of L-arginine by a genetically modified Escherichia...

The aim of the present work was to evaluate the effect of the carbon/nitrogen (COD/N) ratio on the implementation of technologies treatment of swine wastewater (SW). The results show that the chemical processes are efficient for N removal (up to 99%) contained in SW when COD/N ratio is higher than 10 g/g. However, these processes are inefficient in COD removal (< 33%). COD/N ratio parameter is ...

Volume mixing and isotope ratios secured with repeated atmospheric measurements taken with the Sample Analysis at Mars instrument suite on the Curiosity rover are: carbon dioxide (CO2), 0.960(±0.007); argon-40 ((40)Ar), 0.0193(±0.0001); nitrogen (N2), 0.0189(±0.0003); oxygen, 1.45(±0.09) × 10(-3); carbon monoxide, < 1.0 × 10(-3); and (40)Ar/(36)Ar, 1.9(±0.3) × 10(3). The (40)Ar/N2 ratio is 1.7 ...

aims: tehran’s uncontrolled expansion, which promoted housing, public utilities, industries and increase of vehicles caused the problem of air pollution. necessary information about air quality in different places and different times is the first step of combating the air pollution. the purpose of this study was to investigate the annual, monthly and hourly average of 5 criteria air pollutants ...

The possibility of using the nutritionally versatile bacterium Pseudomonas cepacia to produce poly-beta-hydroxyalkanoic acid was evaluated. Chemostat culture showed that growth of P. cepacia became nitrogen limited when the molar carbon-to-nitrogen ratio of the medium fed into the fermentor was above 15. When grown under nitrogen limitation in batch culture with fructose as the sole source of c...

BACKGROUND The concept of adaptive evolution implies underlying genetic mutations conferring a selective advantage to an organism under particular environmental conditions. Thus, a flow cytometry-based strategy was used to study the adaptive evolution in Chlamydomonas reinhardtii wild-type strain CC124 and starchless mutant sta6-1 cells, with respect to lipid metabolism under nitrogen-(N) deple...