Automated Computation of General Perturbations for the Flora Asteroidal Group

1991 ◽  
Vol 9 (1) ◽  
pp. 149-149
Author(s):  
M. F. He ◽  
Zhangjie
Keyword(s):  
Group Method ◽  
Poisson Series ◽  
The Mean ◽  
Series Processor

AbstractThe general perturbations of the asteroids of the Flora group (975″ < n < 1150″, n - the mean daily motion) due to Jupiter have been automatically computed on an IBM 4341 computer with the Hansen method by manipulating Broucke’s Symbolic Poisson Series Processor, and the results have been compared with that computed previously with the Bohlin group method.

scholarly journals Optimal use of SSR markers for varietal identification of upland cotton

2015 ◽  
Vol 50 (7) ◽  
pp. 571-581 ◽  
Author(s):  
Guilherme da Silva Pereira ◽  
Ana Luíza Ramos Cazé ◽  
Michelle Garcia da Silva ◽  
Vanessa Cavalcante Almeida ◽  
Fernanda Oliveira da Cunha Magalhães ◽  
...  
Keyword(s):  
Genetic Distance ◽  
Ssr Markers ◽  
Polymorphic Information Content ◽  
Group Method ◽  
Discrimination Power ◽  
Arithmetic Average ◽  
Pair Group ◽  
Varietal Identification ◽  
The World ◽  
The Mean

Abstract: The objective of this work was to identify polymorphic simple sequence repeat (SSR) markers for varietal identification of cotton and evaluation of the genetic distance among the varieties. Initially, 92 SSR markers were genotyped in 20 Brazilian cotton cultivars. Of this total, 38 loci were polymorphic, two of which were amplified by one primer pair; the mean number of alleles per locus was 2.2. The values of polymorphic information content (PIC) and discrimination power (DP) were, on average, 0.374 and 0.433, respectively. The mean genetic distance was 0.397 (minimum of 0.092 and maximum of 0.641). A panel of 96 varieties originating from different regions of the world was assessed by 21 polymorphic loci derived from 17 selected primer pairs. Among these varieties, the mean genetic distance was 0.387 (minimum of 0 and maximum of 0.786). The dendrograms generated by the unweighted pair group method with arithmetic average (UPGMA) did not reflect the regions of Brazil (20 genotypes) or around the world (96 genotypes), where the varieties or lines were selected. Bootstrap resampling shows that genotype identification is viable with 19 loci. The polymorphic markers evaluated are useful to perform varietal identification in a large panel of cotton varieties and may be applied in studies of the species diversity.

THE ACCURACY OF THE PLATING METHOD FOR ESTIMATING THE NUMBERS OF SOIL BACTERIA, ACTINOMYCES, AND FUNGI IN THE DILUTION PLATED

1939 ◽  
Vol 17c (3) ◽  
pp. 72-86 ◽  
Author(s):  
Norman James ◽  
Marjorie L. Sutherland
Keyword(s):  
Bacterial Population ◽  
Accurate Estimate ◽  
Poisson Series ◽  
Plating Method ◽  
Successive Period ◽  
The Mean ◽  
Data Yield ◽  
Micro Organisms ◽  
Abnormal Variation ◽  
Number Of Bacteria

During the crop seasons of 1936, 1937, and 1938, 1465 samples of field soil, held in the laboratory one day after crushing, were plated by the recognized technique in four replicates of one dilution for counts of fungi, and of a higher dilution for counts of bacteria and of actinomyces. A χ2 value was calculated for each set or counts. These values for each group of micro-organisms were distributed into classes, and the number in each class was compared with the theoretical for the Poisson series. The data for each year indicate that the fungal counts conform to expectancy on the basis of random sampling, and show that the method provides a reasonably accurate estimate of the population in the dilution plated capable of developing under the conditions of growth. Too many sets of counts of bacteria in each year yield high χ2 values. The counts of actinomyces conform to expectancy.In an attempt to determine the cause of this abnormality for sets of counts of bacteria, samples were plated on the afternoon of the day they were taken from the field. Three hundred and four samples plated in six replicates of one dilution, and another 100 samples plated in four replicates, yield χ2 values whose distributions conform to expectancy. Accordingly, the plate method provides a satisfactory estimate of the bacterial population of soil in the dilution plated if the procedure is carried out within six hours after sampling. Data on 88 samples plated on the day of sampling, on 88 samples held one day, on 88 samples held two to five days, and on 88 samples held eight to thirteen days show that the discrepancy between the actual and theoretical distributions of χ2 values becomes progressively greater at each successive period of holding the samples. Further, the data indicate that the area sampled, the season, the medium used and the technique of plating bear no relation to the abnormal variation in counts of bacteria on replicate plates.A record was kept of the presence of abnormal types of bacterial colonies and various genera of fungi on all plates from 468 samples plated one day after sampling and crushing during 1938. The data show that sets having pin-point colonies or spreading colonies of the Mucorales on one or more plates usually have high χ2 values. Counts on such plates should be excluded from the estimate of the mean number of bacteria in the sample. Likewise, the number of actinomyces colonies on each plate from these samples was recorded. The χ2 values for these counts were found to conform to expectancy, indicating that the factor or factors associated with a large number of high χ2 values for counts of bacteria does not affect the count of actinomyces in the same way.Percentage moisture and P values corresponding to χ2 values for the counts of bacteria obtained each year were correlated. The data yield coefficients that are not significant in each case.

Identification and structure analysis of three tilapia species using microsatellite markers

2009 ◽  
Vol 6 (2) ◽  
pp. 119-125
Author(s):  
Song Hong-Mei ◽  
Bai Jun-Jie ◽  
Quan Ying-Chun ◽  
Li Sheng-Jie
Keyword(s):  
Microsatellite Markers ◽  
Clustering Analysis ◽  
Phylogenetic Trees ◽  
Mean Value ◽  
Group Method ◽  
Oreochromis Aureus ◽  
Arithmetic Average ◽  
Pair Group ◽  
Expected Heterozygosity ◽  
The Mean

AbstractSeventeen special loci were selected from 77 microsatellite markers to distinguish three varieties of tilapias, including the six differential loci UNH636, UNH117, UNH172, UNH738, UNH878 and UNH896 in Oreochromis aureus; five differential loci UNH913, UNH907, UNH222, UNH980 and UNH880 in O. niloticus; and six differential loci of UNH876, UNH899, UNH853, UNH932, UNH933 and UNH773 in O. mossambicus. Any one of the 17 loci could amplify particular bands to distinguish one tilapia from the other two. The genetic structure of O. aureus, O. niloticus and O. mossambicus stocks and their phylogenetic relationships were also analysed using these 17 loci. In total 142 alleles were detected, and the average number of alleles per locus was 8.35. Additionally, a clustering analysis was performed based on the result of the Popgen32 software package and phylogenetic trees were constructed by MEGA4 using the unweighted pair group method using arithmetic average (UPGMA). The results showed that the mean value of observed heterozygosity was 0.0941, 0.5490 and 0.2588, the mean value of expected heterozygosity was 0.1089, 0.7230 and 0.1965, and the polymorphism information content was 0.0869, 0.7149 and 0.1643, in O. aureus, O. niloticus and O. mossambicus, respectively. The UPGMA tree demonstrated that O. aureus was more closely related to O. mossambicus than to O. niloticus.

Dilution Egg-Counts and the Poisson Series

1941 ◽  
Vol 19 (3-4) ◽  
pp. 59-62 ◽  
Author(s):  
B. G. Peters
Keyword(s):  
Theoretical Basis ◽  
Reasonable Agreement ◽  
Present Note ◽  
Sampling Technique ◽  
Error Variance ◽  
Mean Square ◽  
Average Effect ◽  
Poisson Series ◽  
The Mean ◽  
Faecal Suspension

Researches involving dilution egg-counts, recently carried out by members of the staff of this Institute, have shown that the error variance, i.e. that between parallel counts, approximates more or less closely to the mean count. The following examples illustrate this point:—The counts were all made by the same technique, and it is fair to total them in order to observe the average effect. This agreement between variance (or mean square) and mean is a feature of the Poisson distribution, and it has been assumed that dilution counts are in fact distributed according to the terms of that series, in all cases where the technique is adequate. Reasonable agreement between mean and error variance becomes, indeed, a criterion of the accuracy of the sampling technique. The purpose of the present note is to enquire a little further into the theoretical basis of this assumption, doubts having arisen as to whether high counts (say, up to 100) can be expected to conform to the Poisson series.The essence of the McMaster (Gordon & Whitlock) technique is that one counts the eggs lying under a centimetre square engraved on a coverglass which is supported 0·15 cm. above a slide, i.e. the eggs contained in 0·15 cc. of faecal suspension. Since the suspending liquid is a half-saturated solution of salt, the eggs float up into one optical plane immediately below the coverglass, this making for ease in counting.

An Outcome Evaluation Instrument for Alcohol Education, Prevention, and Intervention Programs

1984 ◽  
Vol 14 (4) ◽  
pp. 331-346 ◽  
Author(s):  
Sehwan Kim ◽  
Irma R. Hoffman ◽  
Mary Ann Pike ◽  
Jessie Gibson
Keyword(s):  
Attitude Scale ◽  
Outcome Evaluation ◽  
Intervention Programs ◽  
Group Method ◽  
Evaluation Instrument ◽  
Alcohol Education ◽  
Prevention And Intervention ◽  
Alcohol Involvement ◽  
The Common ◽  
The Mean

This study introduces an evaluation instrument entitled, Alcohol Education Evaluation Instrument (AEEI). It is used for outcome evaluation in assessing the effectiveness of various alcohol education, prevention, and intervention programs aimed at deterring teenage alcohol abuse. The instrument is theoretically based. It measures the common objectives of various primary prevention and intervention programs designed to bring about behavioral, intentional, attitudinal, and informational changes. A composite alcohol attitude scale incorporated in the AEEI has shown R = .823 in explaining alcohol involvement among students in grades four through six. Additional properties of the attitudinal scale are obtained through a varimax-rotated factor analytic solution. The mean Cronbach Alpha coefficient of reliability pertaining to the attitudinal scales employed in the AEEI is .923. Criterion-related validity of the scales is established through a known-group method. The groups identified are the current and noncurrent users of alcohol.

scholarly journals A modified method of counting particles

1932 ◽  
Vol 137 (832) ◽  
pp. 434-446 ◽  
Keyword(s):  
Poisson Distribution ◽  
Frequency Distribution ◽  
Experimental Technique ◽  
Standard Error ◽  
Average Density ◽  
Poisson Series ◽  
Modified Method ◽  
The Mean ◽  
Test Of Randomness ◽  
Number Of Particles

Many physical and biological experiments involve the counting of particles which are randomly distributed in space or time. For convenience, the whole of the space or time is divided into a number of zones, and the number of particles in each zone is counted separately. Thus, when using the hæmacytometer, the microscope field is divided into a number of squares, and when counting under the ultramicroscope “snap” readings are taken of a large number of small microscope fields. If a very large number of particles per zone is possible, but the average density is relatively low, the frequency distribution of zones with 0, 1, 2, etc., particles, as deduced from the laws of probabilities, is described by the Poisson series, and this fact is sometimes used as a test of randomness and as a check on experimental technique. Assuming the true mean number of particles per zone to be μ and the number of zones counted to be N, the N counts giving an observed mean of ḿ , the standard error of ḿ , expressed as a ratio of μ, is well known to be √1/μN. Thus, for a given number of zones, the greater the density of particles, the greater is the accuracy of the mean (so long as the Poisson distribution still holds). This is shown by the lowest curve of fig. 1 where the standard error of ḿ for a single count ( σḿ , divided by μ, is plotted against μ.

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