Oil and PCB interactions on the uptake and excretion in midges

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/47989/1/128_2005_Article_BF01625535.pd

Experimental system to displace radioisotopes from upper to deeper soil layers: chemical research

BACKGROUND: Radioisotopes are introduced into the environment following nuclear power plant accidents or nuclear weapons tests. The immobility of these radioactive elements in uppermost soil layers represents a problem for human health, since they can easily be incorporated in the food chain. Preventing their assimilation by plants may be a first step towards the total recovery of contaminated areas. METHODS: The possibility of displacing radionuclides from the most superficial soil layers and their subsequent stabilisation at lower levels were investigated in laboratory trials. An experimental system reproducing the environmental conditions of contaminated areas was designed in plastic columns. A radiopolluted soil sample was treated with solutions containing ions normally used in fertilisation (NO(3)(-), NH(4)(+), PO(4)(--- )and K(+)). RESULTS: Contaminated soils treated with an acid solution of ions NO(3)(-), PO(4)(--- )and K(+), undergo a reduction of radioactivity up to 35%, after a series of washes which simulate one year's rainfall. The capacity of the deepest soil layers to immobilize the radionuclides percolated from the superficial layers was also confirmed. CONCLUSION: The migration of radionuclides towards deeper soil layers, following chemical treatments, and their subsequent stabilization reduces bioavailability in the uppermost soil horizon, preventing at the same time their transfer into the water-bearing stratum

Microbial oxidation and bioluminescence response for toluene and trichloroethylene.

A

Bioluminescent imaging of single bacterial cells using an enhanced ilux operon.

The lux operon is a useful reporter for bioluminescence imaging due to its independence of exogenous luciferin supply, but its relatively low brightness hampers the imaging of single cells. This chapter describes a procedure for the imaging of individual Escherichia coli cells using an improved ilux operon. The enhanced brightness of ilux enables long-term bioluminescence imaging of single bacteria with high sensitivity without the requirement for an external luciferin

Communal nursing in wild house mice is not a by-product of group living: Females choose

Communal nursing, the provision of milk to non-offspring, has been argued to be a non-adaptive by-product of group living. We used 2 years of field data from a wild house mouse population to investigate this question. Communal nursing never occurred among females that previously lacked overlap in nest box use. Females nursed communally in only 33 % of cases in which there was a communal nursing partner available from the same social group. Solitarily nursing females were not socially isolated in their group; nevertheless, high spatial associations prior to reproduction predict which potential female partner was chosen for communal nursing. An increase in partner availability increased the probability of communal nursing, but population density itself had a negative effect, which may reflect increased female reproductive competition during summer. These results argue that females are selective in their choice of nursing partners and provide further support that communal nursing with the right partner is adaptive