4 research outputs found
Biosorption of arsenic and cadmium from aqueous solutions
The biosorption of cadmium and arsenic from aqueous solutions onto the unmodified compact biomass of microscopic filamentous fungus Aspergillus clavatus DESM. was studied in the concentrationrange of 0.25 – 100 mg.l-1. The experimental biosorption results for arsenic and cadmium followed well the Freundlich equilibrium sorption model
Effects of prenatal irradiation on behaviour and hippocampal neurogenesis in adult rats
Prenatal irradiation is known to have aversive effects on the brain development, manifested in changes in some behavioural parameters in adult individuals. The aim of our work was to assess the effect of prenatal irradiation on different forms of behaviour and on hippocampal neurogenesis in rats. Pregnant female rats were irradiated with a dose of 1 Gy of gamma rays on the 16th day of gravidity. The progeny of irradiated and control animals aged 3 months were tested in Morris water maze (MWM), open field (OF) and in elevated plus maze test (PM). The prenatal irradiation negatively influenced the short-term spatial memory in MWM in female rats, although the long-term memory was not impaired. A statistically significant increase of basic locomotor activity in OF was observed in irradiated rats. The comfort behaviour was not altered. The results of PM showed an increase of anxiety in irradiated females. The level of hippocampal neurogenesis, assessed as the number of cells labelled with 5-bromo-2-deoxyuridine in the area of gyrus dentatus, was not statistically different in irradiated rats. Our results indicate, that prenatal irradiation with a low dose of gamma-rays can affect some innate and learned forms of behaviour in adult rats. We did not confirm a relation of behavioural changes to the changes of hippocampal neurogenesis
Removal of arsenic (V) from aqueous solutions using chemically modified sawdust of spruce (Picea abies): Kinetics and isotherm studies
Arsenic is a ubiquitous element in the environment and occurs naturally
in both organic and inorganic forms. Under aerobic condition, the
dominant form of arsenic in waters is arsenate, which is highly mobile
and toxic. Arsenic poisoning from drinking water remains a serious
world health issue. There are various standard methods for arsenic
removal from drinking waters (coagulation, sorption, ion-exchange
reactions or methods of reverse osmosis) and alternative methods, such
as biosorption. Biosorption of arsenic from natural and model waters by
native or chemically modified (with urea or ferric oxyhydroxides) plant
biomass prepared from sawdust of Picea abies was studied. The kinetic
of the adsorption process fitted well the pseudo second order
adsorption model and equilibrium was achieved after 2 h. The results
showed that biosorption was well described by both Langmuir and
Freundlich isotherms. The maximum biosorption capacity of the sawdust
modified with ferric oxyhydroxides, evaluated by Langmuir adsorption
model, was 9.259 mg/g, while the biosorption capacity of unmodified
biosorbent or biosorbent modified with urea was negligible. The
adsorption capacity is comparable to results published by other
authors, suggesting that the prepared chemically modified biosorbent
has potential in remediation of contaminated wate