Soil surface lichens in arid and subarid south-eastern Australia. II. Phytosociology and geographic zonation

1972 ◽  
Vol 20 (2) ◽  
pp. 215 ◽  
Author(s):  
RW Rogers
Keyword(s):  
Principal Components Analysis ◽  
Principal Components ◽  
Group Identification ◽  
Soil Surface ◽  
The Other ◽  
Influence Analysis ◽  
South Eastern ◽  
Eastern Australia ◽  
Species Groups ◽  
Components Analysis

Five lichen species groups were delimited, principal components analysis and influence analysis being used as aids to group identification. With these same techniques it was demonstrated that two of the species groups formed "background" floras in adjacent geographic areas, the other three species groups, being superimposed upon the "background" floras to produce five separate geographic zones of lichen distribution.

Vergelyking tussen die plantegroei en habitatte van die gronde van die Estcourt- en Sterkspruitvorms in die suidoostelike Oranje-Vrystaat

Bothalia ◽  
1978 ◽  
Vol 12 (3) ◽  
pp. 499-511 ◽  
Author(s):  
O. J. H. Bosch
Keyword(s):  
Principal Components Analysis ◽  
Principal Components ◽  
Soil Texture ◽  
Soil Depth ◽  
Floristic Composition ◽  
Habitat Conditions ◽  
Reciprocal Interactions ◽  
South Eastern ◽  
Determining Factors ◽  
Components Analysis

Sample stands of vegetation occurring on the Sterkspruit and Estcourt soil forms in the south-eastern Orange Free State were compared by means of an ordination technicque (principal components analysis). The habitats of the various grass communities were compared to determine whether communities corresponding to one other develop under similar habitat conditions. The floristic composition of the vegetation on soils of the Sterkspruit and Estcourt forms are often similar, although the soil form and other habitat conditions differ markedly. The results of these investigations have shown that this could be due to compensation effects, which are the result of reciprocal interactions mainly between the moisture-determining factors such as soil texture, topography, effective soil depth and degree of erosion.

scholarly journals A Novel Sky-Subtraction Method Based on Non-negative Matrix Factorisation with Sparsity for Multi-object Fibre Spectroscopy

2016 ◽  
Vol 33 ◽  
Author(s):  
Bo Zhang ◽  
Long Zhang ◽  
Zhongfu Ye
Keyword(s):  
Principal Components Analysis ◽  
Principal Components ◽  
Curve Fitting ◽  
The Other ◽  
Subtraction Method ◽  
B Spline ◽  
Spline Curve ◽  
Components Analysis ◽  
Matrix Factorisation

AbstractA novel sky-subtraction method based on non-negative matrix factorisation with sparsity is proposed in this paper. The proposed non-negative matrix factorisation with sparsity method is redesigned for sky-subtraction considering the characteristics of the skylights. It has two constraint terms, one for sparsity and the other for homogeneity. Different from the standard sky-subtraction techniques, such as the B-spline curve fitting methods and the Principal Components Analysis approaches, sky-subtraction based on non-negative matrix factorisation with sparsity method has higher accuracy and flexibility. The non-negative matrix factorisation with sparsity method has research value for the sky-subtraction on multi-object fibre spectroscopic telescope surveys. To demonstrate the effectiveness and superiority of the proposed algorithm, experiments are performed on Large Sky Area Multi-Object Fiber Spectroscopic Telescope data, as the mechanisms of the multi-object fibre spectroscopic telescopes are similar.

Soil Surface Lichens in Arid and Subarid South-Eastern Australia. III. The Relationship Between Distribution and Environment

1972 ◽  
Vol 20 (3) ◽  
pp. 301 ◽  
Author(s):  
RW Rogers
Keyword(s):  
Distribution Pattern ◽  
Climatic Factors ◽  
Arid Zone ◽  
Soil Surface ◽  
Annual Rainfall ◽  
South Eastern ◽  
Mean Annual Rainfall ◽  
Eastern Australia ◽  
Species Groups ◽  
The Relationship

From a consideration of the distribution of species and species groups in relation to soil and climatic factors, it is shown that mean annual rainfall and mean maximum January temperature largely explain the distribution pattern of arid zone soil surface lichens. A past distribution of lichen crusts in southern Australia is postulated on the basis of factors controlling lichen crust development, and known variations from this pattern explained in terms of stocking history.

How distinct is ‘distinct quality’ of mood?

1997 ◽  
Vol 27 (2) ◽  
pp. 445-453 ◽  
Author(s):  
G. PARKER ◽  
J. ROUSSOS ◽  
K. EYERS ◽  
K. WILHELM ◽  
P. MITCHELL ◽  
...  
Keyword(s):  
Principal Components Analysis ◽  
Principal Components ◽  
Mood State ◽  
Quality Criterion ◽  
The Other ◽  
Clinical Feature ◽  
Melancholic Depression ◽  
Dsm Iv ◽  
Components Analysis

Background. The DSM-IV criteria for melancholia include the clinical feature ‘distinct quality’, defined as a mood state differing from that experienced in bereavement. Both propositions – its specificity to melancholia and its definition – remain problematical.Methods. We examine both propositions by analysing an adjective checklist completed by melancholic and non-melancholic depressed subjects, as well as by a bereaved sample. The checklist was refined by a principal components analysis to four scales – one assessing a general ‘mood’ severity or dysphoric dimension, and the other three assessing dimensions of ‘fatigue’, ‘numbness’ and ‘guilt’.Results. If the concept of ‘distinct quality’ has validity, we would require specificity of the refined qualitative constructs to melancholic depression. The ‘numbness’ component met that requirement, but only to a degree. While bereaved subjects did differ from those with melancholic depression on a number of our refined qualitative mood domains, such differences appeared more related to lower levels of depression in the bereaved sample.Conclusions. We argue for deleting the ‘distinct quality’ criterion from diagnostic checklists of melancholia until its definition has been improved, its utility demonstrated and its specificity to any depressive subtype established as having clinical significance.

Sub-syndromes of tardive dyskinesia

1980 ◽  
Vol 10 (3) ◽  
pp. 513-520 ◽  
Author(s):  
T. Kidger ◽  
T. R. E. Barnes ◽  
T. Trauer ◽  
P. J. Taylor
Keyword(s):  
Tardive Dyskinesia ◽  
Head And Neck ◽  
Principal Components Analysis ◽  
Principal Components ◽  
Reliable Method ◽  
The Other ◽  
Parkinsonian Syndrome ◽  
Limb Movements ◽  
Components Analysis

SYNOPSISA reliable method for recording the site and duration of purposeless movements was devised. With this method 267 subjects were studied, 182 of whom had been exposed to neuroleptics. The results were submitted to a principal components analysis and 3 movement dimensions emerged. One group of movements resembled a parkinsonian syndrome. The other 2 groups of movements both conformed to the generally accepted criteria for tardive dyskinesia. These groups were: (1) head and neck movements and (2) trunk and limb movements. The possibility of the second and third groups representing clinically relevant sub-syndromes of tardive dyskinesia is discussed.

scholarly journals Principal Components Analysis Utility in the Livestock Field

2016 ◽  
Vol 73 (2) ◽  
pp. 251
Author(s):  
Ancuta Simona Rotaru ◽  
Ioana Pop ◽  
Anamaria Vatca ◽  
Luisa Andronie
Keyword(s):  
Factor Analysis ◽  
Principal Components Analysis ◽  
Principal Components ◽  
Latent Variables ◽  
Principal Component ◽  
The Other ◽  
Data Sets ◽  
Method Factor ◽  
Two Factors ◽  
Components Analysis

Principal Component Analysis is a method factor - factor analysis - and is used to reduce data complexity by replacingmassive data sets by smaller sets. It is also used to highlight the way in which the variables are correlated with eachother and to determining the (less)latent variableswhich are behind the (more)measured variables. These latent variables are called factors, hence the name of the methodi.e. factor analysis. Our paper shows the applicability of Principal Components Analysis (PCA) in livestock area of study by carrying out a researchon some physiological characteristics in the case of tencow breeds.By using PCA only two factors have been preserved, concentrating over 80% of their information from the four variables in question, one factor concentrating weight and height and the other factor concentrating trunk circumference and weight at calving, respectively.

PRINCIPAL COMPONENTS ANALYSIS OF DATA FROM SAXICOLOUS BRYOPHYTE VEGETATION AT STEPS BRIDGE, DEVON: I A QUANTITATIVE ASSESSMENT OF VARIATION IN THE VEGETATION

1967 ◽  
Vol 45 (1) ◽  
pp. 93-115 ◽  
Author(s):  
G. A. Yarranton
Keyword(s):  
Quantitative Analysis ◽  
Data Processing ◽  
Principal Components Analysis ◽  
Principal Components ◽  
Quantitative Assessment ◽  
Statistical Treatment ◽  
The Other ◽  
Dispersion Matrix ◽  
Components Analysis ◽  
Analysis Of Variation

The aim of the series of three papers, of which this is the first, is to produce a rigorous quantitative analysis of variation in vegetation and to correlate the results of the analysis with environmental variation. A general account is given of the Steps Bridge area and of the vegetation studied. The collection of samples of contact between species in the saxicolous bryophyte vegetation is described. To compare the effects of different methods of data processing, four matrices were calculated: a correlation and a dispersion matrix based on the joint and total occurrences of pairs of species in the samples, and a correlation and a covariance matrix based on the occurrences of pairs of species with all the other species in the samples. Results of principal components analyses of the four matrices are presented and compared and the appropriate circumstances for the use of each type of matrix are indicated. The components analyses are analyses of the distributional relationships of the species and are based on rigorous statistical treatment throughout.

Evaluating Appreciation of Measures Attending to Pupil Diversity (EMAD)

2007 ◽  
Vol 100 (3) ◽  
pp. 783-786
Author(s):  
Margarita Pino ◽  
José Dominguez ◽  
Antonio Lopez-Castedo
Keyword(s):  
Principal Components Analysis ◽  
Factor Structure ◽  
Internal Consistency ◽  
Principal Components ◽  
Primary Schools ◽  
The Other ◽  
Varimax Rotation ◽  
Cronbach Alpha ◽  
Two Factors ◽  
Components Analysis

Evaluating appreciation of measures attending to pupil diversity (EMAD) is a scale for evaluating the understanding of measures describing pupils' cultural and diversity needs among the staff responsible for such measures in Spanish primary schools. Its 9 Likert-scale items correspond to the various types of action in this area that are currently being promoted in Spain. The principal objective of this study was to assess the scale's factor structure and internal consistency, to which end the scale was completed by the heads of the Departments of Orientation of 140 Spanish primary schools. Corrected item-total correlations and Cronbach alpha (.91) indicated adequate scale homogeneity. Principal components analysis followed by varimax rotation indicated two factors jointly accounting for 71.4% of total variance, one associated with actions involving modification of syllabuses, and the other with actions not requiring such changes. Cronbach alphas were .89 and .79 for the two factors.

scholarly journals RAPD Analysis of Hosta Species and Cultivars

HortScience ◽  
1995 ◽  
Vol 30 (4) ◽  
pp. 811E-811
Author(s):  
Jing-Tian Ling ◽  
Nick Gawel ◽  
Roger J. Sauve
Keyword(s):  
Principal Components Analysis ◽  
Principal Components ◽  
Rapd Markers ◽  
Rapd Analysis ◽  
The Other ◽  
Herbaceous Plant ◽  
Phylogenic Analysis ◽  
Components Analysis

The genus of Hosta (plantain lily) is a shade-loving herbaceous plant with attractive foliage. Confusion exists in the genus regarding nomenclature and taxonomy. In this study, the possibility of application of RAPD markers to characterize Hosta species and cultivars was investigated. DNA was extracted from 28 Hosta species and cultivars. Thirty-six of 37 primers generated RAPD markers. Phylogenic analysis and principal components analysis showed groupings among cultivars. Results indicated that H. plantaginea and H. ventricosa were the most distant from the other tested species and cultivars. These results suggest RAPDs may be useful in the identification and analysis of relationships among Hosta.

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