THE STANDARDIZING OF A LABORATORY METHOD FOR COMPARING THE TOXICITY OF CONTACT INSECTICIDES

1943 ◽  
Vol 21d (3) ◽  
pp. 35-75 ◽  
Author(s):  
Frank O. Morrison
Keyword(s):  
Analysis Of Variance ◽  
Laboratory Method ◽  
Curve Analysis ◽  
Toxicity Tests ◽  
Spray Application ◽  
Test Animal ◽  
Good Test ◽  
Different Populations ◽  
Angular Transformation ◽  
Careful Standardization

Toxicity tests were conducted with nicotine sulphate and nicotine alkaloid using Drosophila melanogaster as the test animal, with a modified Tattersfield atomizer spray machine, and by an immersion technique. One hundred and fifty flies were treated at each concentration each day. Each experiment was replicated 8 or 10 times using 3 to 22 concentrations. Data were analysed by the method of analysis of variance and by means of probits.It appears from the data secured that careful standardization of any technique will be needed to secure comparable results. Results from spraying were the more uniform and consistent. Saponin spreader had a synergistic action with nicotine sulphate. It complicates results and its effect cannot be separated from that of the insecticide. Variations in observed mortalities result from different rates of spray application (slower applications were better), different ages of test animals (day-old flies and flies over four days old were most susceptible), different numbers of test animals per container (increased numbers increased the kill), different populations (these vary greatly in susceptibility), differences in larval and adult nutrition, and the use of different sized fly containers. All these factors must be standardized or accounted for. When this was done variations due to different experimenters were not significant.In general six or eight replications were enough to establish a curve. Analysis of variance on angular transformation values gives a good test for consistency and the method of probits reveals much heterogeneity in the data.

Morphometric analysis of some populations of lymnocardiid species (Mollusca: Bivalvia) from Razelm Lake Complex (Romania)

2010 ◽  
Vol 53 (1) ◽  
pp. 13-19 ◽  
Author(s):  
Oana Popa ◽  
Elena Iorgu ◽  
Beatrice Kelemen ◽  
Dumitru Murariu ◽  
Luis Popa
Keyword(s):  
Multivariate Analysis ◽  
Discriminant Analysis ◽  
Analysis Of Variance ◽  
Morphometric Analysis ◽  
Growth Pattern ◽  
Curve Analysis ◽  
Multivariate Analysis Of Variance ◽  
Geographical Variability ◽  
Significant Difference ◽  
Morphological Variables

Morphometric analysis of some populations of lymnocardiid species (Mollusca: Bivalvia) from Razelm Lake Complex (Romania) In this paper we report the morphometric analysis of some populations of Lymnocardiid species from the lakes Razelm and Goloviţa. We used three measurements ratios to perform a discriminant analysis and a multivariate analysis of variance (MANOVA), in order to compare the species Hypanis colorata vs. Hypanis angusticostata in the two lakes, H. colorata in Razelm vs. Goloviţa, and H. angusticostata in Razelm vs. Goloviţa. From this analysis we concluded that the multivariate means of the morphological variables used in this study were highly significantly different (p=3.2e-05) between the two species. Concerning the geographical variability, in both species, the analysis showed no significant difference between the populations in the two investigated lakes. We also determined from a fitting curve analysis, that the growth pattern of both species shows length-height isometry and width-length and width-height negative allometry.

Effects of Sex and Race on Interracial Dating Preferences

1985 ◽  
Vol 57 (3_suppl) ◽  
pp. 1291-1296 ◽  
Author(s):  
Mitchell Korolewicz ◽  
And Ann Korolewicz
Keyword(s):  
New Jersey ◽  
Black Women ◽  
Analysis Of Variance ◽  
Social Distance ◽  
Content Validity ◽  
External Validity ◽  
Item Analysis ◽  
Interracial Dating ◽  
Heterogeneous Sample ◽  
Different Populations

The hypothesis was that sex and race will affect interracial dating preferences, one aspect of social distance. 64 subjects were selected from two different populations, 32 from New Jersey and 32 from Mississippi, to increase the external validity by using a more heterogeneous sample. An interracial dating-preference questionnaire was formulated and an item analysis was done to establish content validity. A 2-way analysis of variance showed sex and race were significant; blacks and black women in particular were more apt to prefer interracial dating.

Post Hoc Quantile Test for One-Way Analysis of Variance Using a Double Bootstrap Method

2005 ◽  
Vol 1908 (1) ◽  
pp. 19-25 ◽  
Author(s):  
Cliff Spiegelman ◽  
Tim J. Gates
Keyword(s):  
Confidence Intervals ◽  
Analysis Of Variance ◽  
Traffic Engineering ◽  
Bootstrap Method ◽  
Positive Effects ◽  
Cutoff Values ◽  
Bootstrap Simulation ◽  
Test Of Hypothesis ◽  
Different Populations ◽  
Post Hoc

Comparing samples from two or more populations is among the most common statistical tasks that engineers and scientists perform. Typically a t-test or one-way or two-way analysis of variance is used to compare the means of different populations. Although these tests are useful for describing differences in means for various populations, they are of limited use for comparison of other population parameters, such as quantiles (i.e., percentiles). Quantile comparisons are useful for examining the changes that occur to portions of the population away from the median. Comparison of speed percentiles is especially important to the traffic engineering profession to determine the effect of various treatments on speeds of faster drivers (e.g., 85th percentile speeds). Simply testing the mean speed values does not indicate whether the differences occur because of slower traffic driving more slowly, faster traffic driving more slowly, or both. Furthermore, are positive effects on faster drivers being masked by contrasting effects on slower drivers? The main obstacle to providing confidence intervals and tests for quantiles is calculating reasonable estimates of variances for the sample quantiles that are far from the median. This paper describes a nonparametric double bootstrapping procedure for direct comparison of quantiles of two or more sample populations. The first bootstrap simulation is used to produce estimates of standard errors for the desired quantiles and thereby overcome the inability to make reasonable variance estimations. The second layer of bootstrap simulations is used to determine the threshold cutoff values based on a desired level of confidence for the test of hypothesis. The cutoff values also may be used to form confidence intervals. The steps of the procedure along with an example of its use are provided.

scholarly journals PEMBERIAN FORMULA PAKAN HERBAL TERHADAP PROFIL LIPID PADA AYAM PEDAGING

2019 ◽  
Vol 13 (12) ◽  
pp. 1847
Author(s):  
Hasan Basri ◽  
Rosalina Edy Swandayani
Keyword(s):  
Experimental Study ◽  
Treatment Group ◽  
Analysis Of Variance ◽  
Test Animal ◽  
Significance Level ◽  
Physiological Conditions ◽  
Randomized Design ◽  
Commercial Feed ◽  
Completely Randomized Design

This study aims to determine the effect of herbal feeds with different formulas to increase the HSL levels and optimize cholesterol, triglyceride, LDL levels. This study is an experimental study with Completely Randomized Design (CRD). Test animal used in this study were 20 broilers and divided into 4 experimental groups, i.e. P0: control given commercial feed, P1: treatment group given a feed formula, P2: the treatment group given the feed formula, P3: the treatment group given the feed formula. Each group consists of 5 replications. The test animal for each treatment was placed randomly. Data obtained was cholesterol, triglycerides, HDL and LDL levels. The data obtained were analyzed using analysis of variance (ANOVA) and followed by Duncan test with 95% of significance level if there were significant differences. The data were analyzed with SPSS 25 software for Windows. The results showed that the level of cholesterol, triglycerides, HDL and LDL were not significantly different (P> 0.05). The conclusion of this study is that the provision of herbal feed formulas is not significant in reducing cholesterol, triglycerides, LDL, levels and increasing HDL levels, but is able to maintain normal physiological conditions.

Mechanical Properties of the Human Heel Pad: A Comparison between Populations

2008 ◽  
Vol 24 (4) ◽  
pp. 377-381 ◽  
Author(s):  
John H. Challis ◽  
Chloe Murdoch ◽  
Samantha L. Winter
Keyword(s):  
Mechanical Properties ◽  
Energy Loss ◽  
Analysis Of Variance ◽  
Distance Runners ◽  
Long Distance ◽  
Heel Pad ◽  
Significant Difference ◽  
Competitive Cyclists ◽  
Different Populations ◽  
Loading And Unloading

The purpose of this study was to compare the heel pad mechanical properties of runners, who repetitively load the heel pad during training, with cyclists who do not load their heel pads during training. Ten competitive long distance runners and 10 competitive cyclists volunteered for this study. The thickness of the unloaded heel pad was measured using realtime B-mode ultrasonography. A heel pad indentation device was used to measure the mechanical properties of the heel pads. To evaluate the differences between the two groups, in heel pad properties, a repeat measures analysis of variance was used (p< .05). Heel pad thickness was not different between groups when normalized with respect to subject height. There was no significant difference between the groups in percentage energy loss during loading and unloading (runners: 61.4% ± 8.6; cyclists: 62.5% ± 4.6). Heel pad stiffness for the runners was statistically significantly less than that of the cyclists (p= .0018; runners: 17.1 N·mm−1± 3.0; cyclists: 20.4 N·mm−1± 4.0). These results indicate that the nature of the activity undertaken by individuals may influence their heel pad properties. This finding may be important when considering differences in heel pad properties between different populations.

Bright-Field Images (Ctem) of Phase Objects at High Resolution

1976 ◽  
Vol 34 ◽  
pp. 490-491 ◽  
Author(s):  
Sumio Iijima
Keyword(s):  
High Resolution ◽  
Electron Beam Irradiation ◽  
Fine Particles ◽  
High Resolution Electron Microscopy ◽  
Good Test ◽  
Resolution Electron ◽  
Single Crystal Films ◽  
Crystal Films ◽  
By Products ◽  
Test Objects

We have developed a technique to prepare thin single crystal films of graphite for use as supporting films for high resolution electron microscopy. As we showed elsewhere (1), these films are completely noiseless and therefore can be used in the observation of phase objects by CTEM, such as single atoms or molecules as a means for overcoming the difficulties because of the background noise which appears with amorphous carbon supporting films, even though they are prepared so as to be less than 20Å thick. Since the graphite films are thinned by reaction with WO3 crystals under electron beam irradiation in the microscope, some small crystallites of WC or WC2 are inevitably left on the films as by-products. These particles are usually found to be over 10-20Å diameter but very fine particles are also formed on the film and these can serve as good test objects for studying the image formation of phase objects.

Analysis of Variance and Covariance

2007 ◽  
Author(s):  
C. Patrick Doncaster ◽  
Andrew J. H. Davey
Keyword(s):  
Analysis Of Variance
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