A Standard Primary Toxicity Bioassay Using Daphnia Magna as a Test Species

1977 ◽  
Vol 12 (1) ◽  
pp. 27-50 ◽  
Author(s):  
L.A. Behie ◽  
J.E. Zajic ◽  
D. Berk ◽  
R.J.P. Brouzes ◽  
V.A. Naish
Keyword(s):  
Statistical Analysis ◽  
Daphnia Magna ◽  
Biological Indicator ◽  
Pulp And Paper ◽  
Toxicity Bioassay ◽  
Simple Method ◽  
Test Species ◽  
Test Organisms ◽  
Dilution Water

Abstract Although Daphnia magna have been widely used in the determination of the toxicity of various substances, there are no reports in the literature that describe a rigorous bioassay method using this organism as a test species. The test described herein involves the standariza-tion of various important aspects of the method such as the age of the test organisms, and the dilution water used for the preparation of the various toxicant concentrations. Also described is a simple method for the statistical analysis of the results. The sensitivity of the proposed bioassay is demonstrated by determining the toxicity of various pulp and paper effluents. Finally, extensive bioassays were carried out simultaneously with rainbow trout and Daphnia magna indicating that Daphnia are as good a biological indicator of acute toxicity as fish.

Effects of Surface Contamination Layers and Roughness on the Determination of Mechanical Properties of Thin Films Using Nanoindentation

2011 ◽  
Author(s):  
Nicholaos G. Demas ◽  
Oyelayo O. Ajayi ◽  
Iqbal Shareef
Keyword(s):  
Thin Films ◽  
Mechanical Properties ◽  
Surface Roughness ◽  
Statistical Analysis ◽  
Surface Contamination ◽  
Properties Of Coatings ◽  
Simple Method ◽  
Nanomechanical Properties ◽  
Steel Substrates

Nanoindentation measurements on TiAlN, CrN, a-C:H:Me, and TiN, deposited on steel substrates have been performed. It was found that the resulting surface roughness/morphology after deposition significantly affects the measurements of nanomechanical properties, while measurements of these properties on the surface may be significantly different than the bulk portion of the coating, exhibiting a lower nanohardness due to the existence of a surface contamination layer. A simple method is proposed for accurately measuring the nanomechanical properties of coatings alleviating the need for excessive statistical analysis and the issues that arise from surface topography and the presence of surface and contamination layers on thin films.

Development of a simple method for the determination of single nucleotide polymorphisms

2010 ◽  
Vol 34 (8) ◽  
pp. S75-S75
Author(s):  
Weifeng Zhu ◽  
Zhuoqi Liu ◽  
Daya Luo ◽  
Xinyao Wu ◽  
Fusheng Wan
Keyword(s):  
Single Nucleotide Polymorphisms ◽  
Nucleotide Polymorphisms ◽  
Simple Method ◽  
Single Nucleotide

PENENTUAN KRITERIA PENILAIAN KESAN JUMLAH LEUKOSIT PADA PEMERIKSAAN APUSAN DARAH TEPI

2018 ◽  
Vol 3 (2) ◽  
pp. 52-61
Author(s):  
Dzikra Arwie ◽  
Islawati
Keyword(s):  
Data Analysis ◽  
Statistical Analysis ◽  
Blood Cells ◽  
Blood Smear ◽  
White Blood Cells ◽  
Peripheral Blood Smear ◽  
Field Of View ◽  
Laboratory Observation ◽  
Number Of Cells

Leukocytes or white blood cells have a characteristic characteristic of different cells. Determination of the impression of the number of leukocytes is determined in the number of cells in the field of view. While the number of viewable field cells expressed is still quite varied. The purpose of this study was to determine the number of leukocytes in the field of view and expressed the impression of a sufficient amount. This research was conducted at the Laboratory of Health Analyst Department Panrita Husada Bulukumba on 9 April 2017 to 14 July 2017. This type of research is a laboratory observation that aims to determine the criteria for assessing the impression of the number of leukocytes on a peripheral blood smear. Data analysis using statistical analysis is the average and standard deviations to determine the impression of the number of leukocytes and use 3 inspection zones. The results of this study obtained results in zone IV the number of leukocyte impressions said to be sufficient was 7-10, in zone V the number of leukocyte impressions said to be sufficient was 4-9, and in zone VI the number of leukocyte impressions said to be sufficient was 3-8.  

Effect of Mercury on the Survival of Daphnia Magna

1990 ◽  
Vol 22 (5) ◽  
pp. 241-246 ◽  
Author(s):  
I. Brković-Popović
Keyword(s):  
Life Span ◽  
Daphnia Magna ◽  
Abiotic Factors ◽  
Total Hardness ◽  
Chemical Characteristics ◽  
Effect Concentration ◽  
Test Organisms ◽  
Lethal Time ◽  
Two Temperatures ◽  
Time Required

The median lethal time (LT) for each concentration of mercury was determined on the basis of mortality curves. Toxicity curves (i.e., the median life-span of Daphniamagna, LT 50, versus the concentration of mercury) for four tested conditions are shown. The experiments were carried out using two diluents of different total hardness (46 and 119 mg/l as CaCO3), at two temperatures (20°C and 25°C). A comparison of the LT 50s of the control organisms with the LT 50s of the test organisms at mercury concentrations of 0.0075 and 0.0050 mg. l-1 showed that the chemical characteristics and temperatures of the mediums tested did not affect the range of the ‘no effect' concentration. However, the incipient LC 50, and the time required for its appearance, did depend on the combination of the abiotic factors tested.

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