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Effect of ethanol and low dietary copper on perinatal and postweanling copper utilization in the ratBaek, Jong Ho 01 November 1988 (has links)
The hypotheses of this research were (1) to test if
the antagonistic effect of ethanol on liver copper could
be seen within a short period when ethanol ingestion,
low dietary copper and high metabolic demand represented
by either pregnancy plus lactation or rapid growth are
simultaneously present and (2) to test if ethanol
ingestion would exaggerate a marginal dietary copper
status to an obvious copper deficiency.
Pregnant rats were fed liquid diets containing
either 0.75 (low) or 3.75 (control) mg copper/L with or
without 30% of kcal from ethanol throughout gestation
and the first 15 days of lactation. Maternal ethanol
intake failed to exaggerate a marginal copper status to
a copper deficient anemia in both dams and pups as
estimated by concentrations of hemoglobin and liver iron
and oxidase activity of the copper-metalloenzyme
ceruloplasmin. However, maternal ethanol intake did depress maternal liver copper concentration when diet
copper was low (interactive effect P<0.05). This effect
was specific for liver because other tissue copper
concentration was unaffected by ethanol. Although
ethanol depressed total pup liver copper concentration
regardless of dietary copper level, the interactive
effect seen in maternal liver was reflected in copper
content of the pup liver metallothionein fraction eluted
from a Sephadex G-75 column. At least part of the
depressive effect of ethanol on pup liver copper can be
explained by elevated pup serum corticosterone (r=-0.61,
P<0.001), a hormone known to enhance loss of neonatal
liver copper by way of biliary excretion. On the other
hand, the copper status of weanling female rats which
were fed liquid diets containing either 0.5 (low) or 2.5
(control) mg copper/L for 5 weeks was unaffected by
ethanol.
Results demonstrate that the depressive effect of
ethanol on liver copper can be seen within a period of
weeks rather than months when ethanol ingestion, low
dietary copper and pregnancy plus lactation are
simultaneously present in contrast to non-pregnancy.
This ethanol and copper interaction during reproduction,
however, can not be detected if only either serum copper
or oxidase activity of ceruloplasmin is used as an
indicator of copper status. / Graduation date: 1989
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The assessment of copper and zinc removal from highway stormwater runoff using Apatite II™Huang, Hsiao-Wen 31 May 2012 (has links)
Copper and zinc are heavy metals commonly present in highway stormwater runoff. Discharge of these metals to surface waters inhabited by sensitive aquatic species including threatened and endangered salmonids has necessitated the need for improved treatment techniques. Although copper is of the greater toxicological concern, zinc is often present at concentrations several times higher than copper and may compete with copper during adsorptive treatment processes. In the current study, the ability biogenic fish-bone based alternative adsorbent, Apatite II™, for copper and zinc removal from synthetic stormwater runoff was evaluated. Batch experiments were employed to examine equilibrium removal and rapid small scale column tests (RSSCT) were used to simulate dynamic operation in continuous systems. In both batch and continuous systems, the release of phosphate and calcium were observed, and Apatite II™ achieved high removal efficiencies. The removal of copper and zinc was likely due to a combination of processes including adsorption, ion exchange and precipitation. Precipitation played a dominant role in copper removal and the release of phosphate and pH buffering appear to drive this process. While precipitation was also quite important for zinc removal, adsorptive removal also played a role. The findings from the current study provide a general understanding of the performance of copper and zinc removal from stormwater runoff using Apatite II™. / Graduation date: 2012
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