background and objectives: phlomis olivieri benth. (lamiaceae) is a medicinal plant widely distributed in iran. in the present study, we have investigated the phytochemical constituents, antioxidant activity and general toxicity potential of the aerial parts of this species. methods: silica gel (normal and reversed phases) and sephadex lh-20 column chromatographies were used for isolation of co...

The brine shrimp Artemia parthenogenetica (Crustacea, Branchiopoda) is intermediate host for several cestode species whose final hosts are waterbirds. Previous field studies have shown that brine shrimps infected with cestodes have a bright red colour and are spatially segregated in the water column. However, the ethological mechanisms explaining such field observations are unknown. Changes in ...

Alkaline earth elements and alkali metals (Mg, Ca, Na and K) play an important role in the geochemical evolution of saline lakes as the final brine type is defined by the abundance of these elements. The role of major ions in brine evolution has been studied in great detail, but little has been done to investigate the behaviour of minor alkali elements in these systems despite their similar che...

Saline lakes provide a prey-rich, predator-free environment for birds to utilize during migration and stopover periods. The Great Salt Lake (GSL), Utah is the largest salt lake in North America and is utilized by millions of migratory birds. It also is host to multiple commercial endeavors. Proposed expansion of commercial use of the GSL would result in increased impounded area and water extrac...

Growth promoters play an important role in the animal agriculture industry as they facilitate to improve productivity mainly through reduction of pathogenic bacterial load in the gut. Ban and restrictions on the usage of Antibiotic Growth Promoters (AGP) due to public health concerns has made it essential to search alternatives from the herbal sources. But at the same time it is tricky to choos...

Laboratory experiments and field trials have shown that oil recovery from carbonate reservoirs can be increased by modifying the brine composition injected during recovery in a process termed controlled salinity water-flooding (CSW). However, CSW remains poorly understood and there is no method to predict the optimum CSW composition. This work demonstrates for the first time that improved oil r...

The Biochemist — February 2005. © 2005 Biochemical Society 12 of metres thick. The majority of the ice in the Southern Ocean lasts only less than 1 year, and the average Antarctic sea ice thickness is 1 m. In contrast, in the Arctic Ocean sea ice can last several years and the average thickness is generally 2 m. When ice forms from freshwater, the result is a hard brittle solid with the primary...

We incorporate CO2 dissolution due to convective mixing into a sharp-interface mathematical model for the post-injection migration of a plume of CO2 in a saline aquifer. The model captures CO2 migration due to groundwater flow and aquifer slope, as well as residual trapping and dissolution. We also account for the tongued shape of the plume at the end of the injection period. We solve the model...

Lake Vida, one of the largest lakes in the McMurdo Dry Valleys of Antarctica, was previously believed to be shallow (<10 m) and frozen to its bed year-round. New ice-core analysis and temperature data show that beneath 19 m of ice is a water column composed of a NaCl brine with a salinity seven times that of seawater that remains liquid below -10 degrees C. The ice cover thickens at both its ba...

Ice clouds in the Earth's upper troposphere can form via homogeneous nucleation of ice in aqueous droplets. In this study we investigate the crystallisation, or lack of crystallisation, of the solute phase and ice in aqueous (NH(4))(3)H(SO(4))(2)/H(2)O and NH(4)HSO(4)/H(2)O droplets. This is done using in situ X-ray diffraction of emulsified solution droplets mounted on a cold stage. From the d...