Variation of Polyporus tomentosus in cultural characteristics and pathogenicity on conifer seedlings

1977 ◽  
Vol 55 (10) ◽  
pp. 1389-1398 ◽  
Author(s):  
R. D. Whitney ◽  
W. P. Bohaychuk
Keyword(s):  
Growth Rate ◽  
Principal Components Analysis ◽  
Norway Spruce ◽  
Principal Components ◽  
Growth Rates ◽  
White Spruce ◽  
Considerable Influence ◽  
Cultural Characteristics ◽  
Conifer Seedlings ◽  
Components Analysis

Polyporus tomentosus Fr. cultures newly isolated from wood showed faster growth rates, greater chlamydospore numbers at 20 °C, higher average oxidase reactions, and higher disease ratings on seedlings of white spruce and Norway spruce than did cultures maintained on artificial media for 1 year or longer.Data from 30 isolates were analyzed for 63 characters using a principal components analysis as an ordination technique. Variables which had considerable influence on the ordination were pathogenicity on seedlings, isolate growth rate, chlamydospore production, and mat color on artificial media. Pathogenicity was higher among isolates from sporophores with straight setae than among those from sporophores with strongly curved or hooked setae (P. tomentosus var. circinatus F. sensu Haddow).Low pathogenicity on seedlings is an additional character associated with P. tomentosus var. circinatus Fr. which Haddow (Br. Mycol. Soc. Trans. 25: 179–190) separated on the basis of curved setae in the hymenium. Straight setae were always associated with stipitate sporophores and curved setae consistently occurred on sessile sporophores.

Diagnoses Generated by Numerical Taxonomic Methods Applied to Standard Blood Variables

1980 ◽  
Vol 19 (04) ◽  
pp. 205-209
Author(s):  
L. A. Abbott ◽  
J. B. Mitton
Keyword(s):  
Liver Cirrhosis ◽  
Renal Disease ◽  
Principal Components Analysis ◽  
Discriminant Function ◽  
Principal Components ◽  
Discriminant Function Analysis ◽  
Chronic Renal Disease ◽  
Function Analysis ◽  
Infectious Hepatitis ◽  
Components Analysis

Data taken from the blood of 262 patients diagnosed for malabsorption, elective cholecystectomy, acute cholecystitis, infectious hepatitis, liver cirrhosis, or chronic renal disease were analyzed with three numerical taxonomy (NT) methods : cluster analysis, principal components analysis, and discriminant function analysis. Principal components analysis revealed discrete clusters of patients suffering from chronic renal disease, liver cirrhosis, and infectious hepatitis, which could be displayed by NT clustering as well as by plotting, but other disease groups were poorly defined. Sharper resolution of the same disease groups was attained by discriminant function analysis.

Assamese vowels and vowel harmony

2020 ◽  
Vol 6 (2) ◽  
pp. 151-183
Author(s):  
Diana B. Archangeli ◽  
Jonathan Yip
Keyword(s):  
Physical Properties ◽  
Principal Components Analysis ◽  
Principal Components ◽  
Vowel Harmony ◽  
Language Community ◽  
Acoustic Data ◽  
Apparent Loss ◽  
Root Position ◽  
Components Analysis ◽  
Open Question

AbstractBased on impressionistic and acoustic data, Assamese is described as having a phonological tongue root harmony system, with blocking by certain phonological configurations and over-application in certain morphological contexts. This study explores physical properties of the patterns using ultrasonic imaging to determine whether the impressionistic descriptions match what speakers actually do. Principal components analysis (PCA) determines that most participants produce a contrast in tongue root position in the appropriate contexts, though there is less of an impact on tongue root with greater distance from the triggering vowel. Analysis uses the root mean squared distance (RMSD) calculation to determine whether both blocking and over-application take effect. The blocking results conform to the impressionistic descriptions. With over-application, [e] and [o] are expected; while some speakers clearly produce these vowels, others articulate a vowel that is indeterminant between the expected [e]/[o] and an unexpected [ɛ]/[ɔ]. No speaker consistently showed the expected tongue root position in all contexts, and some speakers appeared to have lost the contrast entirely, yet all are considered to be speakers of the same dialect of Assamese. Whether this (apparent) loss is a consequence of crude research methodologies or accurately reflects what is happening within the language community remains an open question.

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