Beneficial and Toxic Effects of Chromium in Plants: Solution Culture, Pot and Field Studies.

The use of different nanoparticles (NPs) is growing every year since discoveries of their unique properties. The wide use of nanomaterials has raised concerns about their safety and possible accumulation in the aquatic environment. Mussels are being considered as one of the most suitable organisms for bioaccumulation monitoring. Within our study, we focused on developing the method that can be applied in field studies of ecotoxicity and can be nondestructive and informative at early times of exposure, while at the same time being based on changes of physiological parameters of fresh water mussels. The changes in the cardiovascular and neural systems of mollusks (Anodonta anatina and Unio tumidus) were measured as biomarkers of toxic effects. Different monometallic and bimetallic NPs, silicon NPs with various ligands were applied as test substances. Changes in cardiovascular and neural functions were in good correlation with accumulation tests for all tested NPs.

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Effect of simulated wet spring conditions on the relative efficiency of three forms of nitrogen fertilizer on grassland

The Journal of Agricultural Science ◽

10.1017/s002185960006696x ◽

1986 ◽

Vol 107 (1) ◽

pp. 219-222 ◽

Cited By ~ 7

Author(s):

Catherine J. Watson ◽

S. N. Adams

Keyword(s):

Field Experiments ◽

Field Studies ◽

Ammonium Nitrogen ◽

Solution Culture ◽

Fertilizer Efficiency ◽

Yield Response ◽

Soil Conditions ◽

Climatic Effects ◽

Ammonium N

There is evidence from solution culture studies that ammonium nitrogen is taken up by grass preferentially to NO3-N at low temperatures (Clarkson & Warner, 1979). In addition NH4 ions are less subject to leaching losses or denitrification (Ryden, 1982). It has been speculated therefore that ammonium N could be the best form of nitrogen for early grass, especially in wet springs. Field experiments have studied the efficiency of different nitrogen forms at the first application over a number of years (McAllister et al. 1965; Van Burg, Dilz & Prins, 1982). The yield response has tended to be variable and may have depended on climatic and soil conditions. Investigations of climatic effects on fertilizer efficiency have often necessitated long-term field studies, but it is proposed that the importance of rainfall in particular could be investigated by means of a short-term irrigation experiment. This paper reports such an experiment using irrigation to simulate a wet spring while keeping other conditions the same for all treatments.

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Environmental Studies of a Marine Wastewater Discharge from a Sulphite Pulp Mill – Example of a General Study Approach for Marine Industrial Discharges

Water Science & Technology ◽

10.2166/wst.1991.0411 ◽

1991 ◽

Vol 23 (1-3) ◽

pp. 151-161 ◽

Cited By ~ 5

Author(s):

N. Nyholm ◽

H. Bach ◽

J. Birklund ◽

T. L. Jensen ◽

K. O. Kusk ◽

...

Keyword(s):

Environmental Impact ◽

Pulp Mill ◽

Environmental Studies ◽

Field Studies ◽

Oxygen Depletion ◽

Toxic Effects ◽

General Study ◽

Study Approach ◽

Fate Modelling ◽

Biological Field

The results of comprehensive environmental studies of a marine discharge from a pulp mill is presented to illustrate a general strategy for environmental impact assessment and management of marine industrial wastewater discharges. The strategy includes the following elements: 1) a thorough chemical and ecotoxicological characterization of the wastewater which also involves degradability studies, 2) field monitoring, 3) cage studies with transplanted organisms, 4) hydrographical studies and subsequent dilution and fate modelling of wastewater and wastewater constituents, and 5) quantitative evaluation of the environmental impact as well as predictive evaluations of possible abatement measures by using the combined results of laboratory tests/chemical analyses and dilution/fate modelling to confine areas around the outfall, where adverse effects of various categories can be expected under various environmental settings. Results from field studies are used for comparison/verification. The present study deals with a discharge of unbleached semichemical sulphite pulp effluent which caused oxygen depletion and toxic effects, in particular towards phytoplankton algae. The usefulness of the general study approach was demonstrated and it was concluded in this case that biological field data alone gave limited clues to assessing nor to mitigating the pollution. This was due to the time and spacial variability of the data, and the limited possibilities of distinguishing effects of occasional oxygen depletion from toxic effects. Biological field studies were useful to assess the problem initially, however, and necessary to complement the calculated estimates both qualitatively and to give the study credibility.

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Ultrastructure of the effect of T-514 obtained from Karwinskia humboldtiana on assembly and integrity of yeast's peroxisomes

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100084983 ◽

1991 ◽

Vol 49 ◽

pp. 136-137

Author(s):

J. Sepulveda-Saavedra ◽

I. Vander-Klei ◽

M. Venhuis ◽

Y. Piñeyro-Lopez

Keyword(s):

Culture Conditions ◽

Toxic Effects ◽

Candida Boidinii ◽

Central Mexico ◽

Poisonous Plant ◽

Biological Behaviour ◽

Enzyme Content ◽

Fat Deposits ◽

Yeast Model

Karwinskia humboldtiana is a poisonous plant that grows in semi desertic areas in north and central México. It produces several substances with different toxic effects. One of them designated T-514 damages severely the lung, kidney and liver, producing in the hepatoeyte large intracellular fat deposits and necrosis. Preliminary observations demonstrated that three is a decrease in the amount of peroxisomes in the hepatocytes of experimentally intoxicated rats and monkeys. To study the effect exerted by the T-514 on peroxisomes, a yeast model was selected, thus, three species: Saccha romices cerevisiae, Ilansenula polymorpha and Candida boidinii were used, because there is information concerning their peroxisome's morphology, enzyme content, biological behaviour under different culture conditions and biogenesis.

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Some Conditions Necessary for Pinocytosis

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100100457 ◽

1968 ◽

Vol 26 ◽

pp. 142-143

Author(s):

M. W. Brightman

Keyword(s):

Smooth Muscle ◽

Cell Membrane ◽

Toxic Effects ◽

Cytological Evidence ◽

Cell Processes

The cytological evidence for pinocytosis is the focal infolding of the cell membrane to form surface pits that eventually pinch off and move into the cytoplasm. This activity, which can be inhibited by oxidative and glycolytic poisons, is performed only by cell processes that are at least 300A wide. However, the interpretation of such toxic effects becomes equivocal if the membrane invaginations do not normally lead to the formation of migratory vesicles, as in some endothelia and in smooth muscle. The present study is an attempt to set forth some conditions under which pinocytosis, as distinct from the mere inclusion of material in surface invaginations, can take place.

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