Toxicity and accumulation of zinc and copper in Hyalella azteca exposed to metal-spiked sediments

1997 ◽  
Vol 54 (5) ◽  
pp. 1046-1054 ◽  
Author(s):  
U Borgmann ◽  
W P Norwood
Keyword(s):  
Chronic Toxicity ◽  
Sediment Toxicity ◽  
Copper Toxicity ◽  
Hyalella Azteca ◽  
Gut Contents ◽  
Copper Accumulation ◽  
Zinc Toxicity ◽  
Short Term ◽  
Spiked Sediment ◽  
The Relationship

The relationship between zinc and copper toxicity in Hyalella azteca and accumulation from metal-spiked sediments was determined for future use in identifying sites where these metals contribute to sediment toxicity. Both zinc and copper accumulation increased rapidly with increasing sediment concentrations, showing no evidence of saturation as seen in waterborne exposures. Zinc accumulation from zinc spiked sediments was substantial, even at concentrations below those causing chronic toxicity, and body concentrations can readily be used to infer chronic toxicity. Chronic toxicity in spiked sediment exposures occurred at excess (above background) body concentrations twice as high as in waterborne exposures, possibly as a result of zinc in gut contents. In contrast, chronic copper toxicity occurred at body concentrations lower than those observed in waterborne exposures. Furthermore, body copper at low sediment exposures was independent of copper in sediment. Body copper concentrations can be used to infer short-term (1-week) toxicity but not chronic toxicity. Copper, but not zinc, caused a reduction in growth, even at concentrations below the 4-week LC25. Reduced growth can, therefore, be used to differentiate between chronic copper and zinc toxicity in sediments.

Identification of the toxic agent in metal-contaminated sediments from Manitouwadge Lake, Ontario, using toxicity–accumulation relationships in Hyalella azteca

1997 ◽  
Vol 54 (5) ◽  
pp. 1055-1063
Author(s):  
U Borgmann ◽  
W P Norwood
Keyword(s):  
Copper Toxicity ◽  
Lake Ontario ◽  
Contaminated Site ◽  
Laboratory Animals ◽  
Copper Accumulation ◽  
Zinc Toxicity ◽  
Metal Availability ◽  
Growth Reduction ◽  
Short Term ◽  
Toxic Agent

Toxicity of sediments from Manitouwadge Lake, Ontario, to Hyalella correlated closely with bioaccumulation of zinc but not copper. Bioaccumulation in 1-week exposures was sufficient to infer chronic zinc toxicity. Close similarity between toxicity-accumulation relationships from Manitouwadge Lake and those obtained from zinc-spiked Hamilton Harbour sediments indicate that toxicity is due to zinc itself and not some other chemical that correlates with zinc in sediments. Sediment concentrations of zinc, on the other hand, are unreliable indicators of effects; toxicity was not highest in sediments from the most contaminated site. Copper accumulation was insufficient to cause short-term (1-week) toxicity. Chronic copper toxicity cannot be predicted from bioaccumulation, but the absence of a significant growth reduction, which is specific to copper, strongly suggests that the contribution of copper to chronic toxicity was minimal. Body concentrations of zinc and copper in wild animals from contaminated lakes (in contrast to laboratory animals exposed to sediments from those lakes) are not reliable indicators of metal toxicity, either because these amphipods have adapted to contaminated conditions or because they survive in selected microhabitats with reduced metal availability.

INTERLABORATORY EVALUATION OF HYALELLA AZTECA AND CHIRONOMUS TENTANS SHORT-TERM AND LONG-TERM SEDIMENT TOXICITY TESTS

2006 ◽  
Vol 25 (10) ◽  
pp. 2662 ◽  
Author(s):  
Teresa J. Norberg-King ◽  
Paul K. Sibley ◽  
G. Allen Burton ◽  
Christopher G. Ingersoll ◽  
Nile E. Kemble ◽  
...  
Keyword(s):  
Sediment Toxicity ◽  
Hyalella Azteca ◽  
Toxicity Tests ◽  
Chironomus Tentans ◽  
Short Term ◽  
Sediment Toxicity Tests

Evaluation of the Efficacy of ST2 and NT-proBNP in the Diagnosis and Prediction of Short- Term Prognosis in Heart Failure with Reduced Ejection Fraction

2017 ◽  
Vol 9 (04) ◽  
Author(s):  
Shivananda B Nayak ◽  
Dharindra Sawh ◽  
Brandon Scott ◽  
Vestra Sears ◽  
Kareshma Seebalack ◽  
...  
Keyword(s):  
Heart Failure ◽  
Ejection Fraction ◽  
Cardiac Biomarkers ◽  
Double Blind Study ◽  
Short Term ◽  
Double Blind ◽  
Reduced Ejection Fraction ◽  
The Mean ◽  
Design And Methods ◽  
The Relationship

Purpose: i) To determine the relationship between the cardiac biomarkers ST2 and NT-proBNP with ejection fraction (EF) in heart failure (HF) patients. ii) Assess whether a superiority existed between the aforementioned cardiac markers in diagnosing the HF with reduced EF. iii) Determine the efficacy of both biomarkers in predicting a 30-day cardiovascular event and rehospitalization in patients with HF with reduced EF iv) To assess the influence of age, gender, BMI, anaemia and renal failure on the ST2 and NT-proBNP levels. Design and Methods: A prospective double-blind study was conducted to obtain data from a sample of 64 cardiology patients. A blood sample was collected to test for ST2 and NT-proBNP. An echocardiogram (to obtain EF value), electrocardiogram and questionnaire were also obtained. Results: Of the 64 patients enrolled, 59.4% of the population had an EF less than 40%. At the end of the 30- day period, 7 patients were warded, 37 were not warded, one died and 17 were non respondent. Both biomarkers were efficacious at diagnosing HF with a reduced EF. However, neither of them were efficacious in predicting 30-day rehospitalization. The mean NT-proBNP values being: not rehospitalized (2114.7486) and 30 day rehospitalization (1008.42860) and the mean ST2 values being: not rehospitalized (336.1975), and 30-day rehospitalization. (281.9657). Conclusion: Neither ST2 or NT-proBNP was efficacious in predicting the short- term prognosis in HF with reduced EF. Both however were successful at confirming the diagnosis of HF in HF patients with reduced EF.

Plebiscitary Politics and the Threats to Legality

2019 ◽  
pp. 275-289
Author(s):  
Claudius Härpfer
Keyword(s):  
The State ◽  
Short Term ◽  
Political Processes ◽  
The Face ◽  
State Of Affairs ◽  
The Relationship

In recent times we find many plebiscitary acts that seek to democratically legitimize political processes in any direction. They have in common that they interrupt the normal routine of representative democracies to a certain degree and create an extra-daily state of affairs, which entails not only direct but also indirect consequences. The text attempts to systematize some of these mechanisms from a Weberian perspective using Brexit as an example. After a brief overview of Weber’s short-term politically inspired statements on plebiscitary democracy, the text systematizes Weber’s understanding of the state as a bureaucratic apparatus that requires any kind of leader to be controlled. Subsequently, the text discusses the relationship between domination, legality, and rationality in order to finally point out the danger of erosion of truth and legality through the emergence of competing consensus communities in the face of competing conceptions of order.

Parasites and promiscuity: Acute disease salience leads to more restricted sexual attitudes

2021 ◽  
pp. 026540752110309
Author(s):  
James B. Moran ◽  
Nicholas Kerry ◽  
Jin X. Goh ◽  
Damian R. Murray
Keyword(s):  
Social Behavior ◽  
Sexual Attitudes ◽  
Experimental Manipulation ◽  
Sexual Relationships ◽  
Experimental Results ◽  
Acute Disease ◽  
Short Term ◽  
Attitudes And Behaviors ◽  
The Relationship ◽  
Sexual Promiscuity

How does disease threat influence sexual attitudes and behaviors? Although research on the influence of disease threat on social behavior has grown considerably, the relationship between perceived disease threat and sexual attitudes remains unclear. The current preregistered study (analyzed N = 510), investigated how experimental reminders of disease threat influence attitudes and anticipated future behaviors pertaining to short-term sexual relationships, using an ecologically valid disease prime. The central preregistered prediction was that experimental manipulation of disease threat would lead to less favorable attitudes and inclinations toward sexual promiscuity. Results were consistent with this preregistered prediction, relative to both a neutral control condition and a non-disease threat condition. These experimental results were buttressed by the finding that dispositional variation in worry about disease threat predicted less favorable attitudes and inclinations toward short-term sexual relationships. This study represents the first preregistered investigation of the implications of acute disease threat for sexual attitudes.

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