scholarly journals Comparative analysis of populations of the Balkan endemic species Daphne malyana Blecic (Thymeleaceae)

2010 ◽  
Vol 62 (4) ◽  
pp. 1151-1162 ◽  
Author(s):  
Marina Juskovic ◽  
P. Vasiljevic ◽  
V. Randjelovic ◽  
V. Stevanovic ◽  
Branka Stevanovic
Keyword(s):  
Principal Component Analysis ◽  
Comparative Analysis ◽  
Endemic Species ◽  
Morphological Variability ◽  
Principal Component ◽  
Balkan Peninsula ◽  
Canonical Discriminant Analysis ◽  
The Other ◽  
Isolated Populations ◽  
Microclimate Conditions

Daphne malyana Blecic (Thymeleaceae) is an endemic species of the western part of the Balkan Peninsula, distributed in the mountains, canyons and gorges of N. Montenegro, E. Bosnia and W. Serbia. The comparative morphoanatomic investigations have included four distantly separated populations of the species D. malyana, i.e. two from Serbia, from the ravines of Sokoline and Vranjak on Mt. Tara, and two from Montenegro, in the canyons of the Tara and Piva rivers. Comparative morphoanatomical studies have shown the presence of general adaptive characteristics of a specific, conservative xeromorphic type, slightly differing in each population. Principal component analysis (PCA) and canonical discriminant analysis (CDA) of 20 morphoanatomical characteristics of the leaves and stems have shown a clear distinction between the populations from the river Piva canyon (Montenegro) and those from the Sokoline ravine (Serbia), on one side, and those of Vranjak gorge (Serbia) and of the river Tara canyon (Montenegro) on the other side. It may be assumed that the mild morphological variability of the isolated populations of the Balkan endemic species D. malyana in the canyons and gorges seem to have been affected by the microclimate conditions in their habitats.

scholarly journals Morphological Differentiation of Polish Arabian Horses - Multivariate Analysis

2012 ◽  
Vol 56 (4) ◽  
pp. 623-629 ◽  
Author(s):  
Dorota Sobczuk ◽  
Marcin Komosa
Keyword(s):  
Principal Component Analysis ◽  
Multivariate Analysis ◽  
Morphological Differentiation ◽  
Principal Component ◽  
Canonical Discriminant Analysis ◽  
The Other ◽  
Multidimensional Data ◽  
Discriminative Power ◽  
Metrical Pattern ◽  
Metric Traits

Abstract The aim of the study was to show the variability of exterior type in Arabian horses bred in three leading stud farms in Poland. A total of 334 adult animals from the basic herd of stud farms in Bialka, Janow Podlaski, and Michalow were studied. Each horse underwent 26 exterior measurements. In the first stage, the method of exploration of multidimensional data - principal component analysis, was used, and subsequently, a stepwise canonical discriminant analysis. It was found that each stud farm breeds horses with a different metrical pattern. Horses bred in Bialka represent clearly different morphotype comparing to horses from the other stud farms. Individuals from Janow Podlaski are more similar to horses originating from Michalow but morphological variation also occurs between them. From among the 26 metric traits, 10 parameters have a meaningful discriminative power. These include in particular such parameters as the length of the metatarsus, pelvis, arm, and neck, and depth of the chest.

scholarly journals Discrimination of brazilian red varietal wines according to their sensory descriptors

2011 ◽  
Vol 35 (6) ◽  
pp. 1172-1176 ◽  
Author(s):  
Alberto Miele ◽  
Luiz Antenor Rizzon
Keyword(s):  
Principal Component Analysis ◽  
Total Variation ◽  
Principal Component ◽  
Pinot Noir ◽  
The Other ◽  
Sensory Characteristics ◽  
Cabernet Sauvignon ◽  
Sensory Panel ◽  
Red Grape ◽  
Grape Varieties

The purpose of this paper was to establish the sensory characteristics of wines made from old and newly introduced red grape varieties. To attain this objective, 16 Brazilian red varietal wines were evaluated by a sensory panel of enologists who assessed wines according to their aroma and flavor descriptors. A 90 mm unstructured scale was used to quantify the intensity of 26 descriptors, which were analyzed by means of the Principal Component Analysis (PCA). The PCA showed that three important components represented 74.11% of the total variation. PC 1 discriminated Tempranillo, Marselan and Ruby Cabernet wines, with Tempranillo being characterized by its equilibrium, quality, harmony, persistence and body, as well as by, fruity, spicy and oaky characters. The other two varietals were defined by vegetal, oaky and salty characteristics; PC 2 discriminated Pinot Noir, Sangiovese, Cabernet Sauvignon and Arinarnoa, where Pinot Noir was characterized by its floral flavor; PC 3 discriminated only Malbec, which had weak, floral and fruity characteristics. The other varietal wines did not show important discriminating effects.

scholarly journals Morphological variability between diploid and tetraploid taxa of the genus Betula L. in the Czech Republic

2017 ◽  
Vol 63 (No. 12) ◽  
pp. 531-537 ◽  
Author(s):  
Linda Rostislav ◽  
Kuneš Ivan ◽  
Baláš Martin ◽  
Gallo Josef
Keyword(s):  
Principal Component Analysis ◽  
Czech Republic ◽  
Reliable Method ◽  
Morphological Variability ◽  
Principal Component ◽  
The Czech Republic ◽  
Forest Region ◽  
Blade Width ◽  
The Bohemian Forest ◽  
Classification Function

The aim of this work was to suggest a reliable method for distinguishing between diploid and tetraploid taxa of the genus Betula Linnaeus, based on leaf measurements. In total, 97 individuals from 6 locations within the Bohemian Forest region (Czech Republic) were selected. Four leaves from each individual were evaluated. On each leaf, twenty parameters were measured. Each sample was analysed by flow cytometry to determine its actual ploidy. Measured parameters were analysed by principal component analysis and tested for differences between diploid and tetraploid taxa. For actual ploidy prediction, a classification function was designed. The reliability of the classification function was verified on samples from three different regions of the Czech Republic and compared with functions as suggested by other authors. The classification function designed in this work (based on 3 parameters – blade width in the upper 1/4 of blade length, first vein angle and number of leaf teeth between 3<sup>rd</sup> and 4<sup>th</sup> vein) correctly determined actual ploidy in 89% of all tested samples.

Morphological variation in the genus Juliomys (Rodentia: Cricetidae: Sigmodontinae) and taxonomic status of Juliomys anoblepas (Winge 1887) from the Quaternary of Southeast Brazil

Zootaxa ◽  
2020 ◽  
Vol 4861 (3) ◽  
pp. 429-443
Author(s):  
CAROLINA PIRES ◽  
MARCELO WEKSLER ◽  
CIBELE R. BONVICINO
Keyword(s):  
Principal Component Analysis ◽  
Morphological Variation ◽  
Morphological Analysis ◽  
Principal Component ◽  
Taxonomic Status ◽  
Morphological Characters ◽  
The Other ◽  
Anterior Portion ◽  
Living Species ◽  
Qualitative Characters

The region of Lagoa Santa, Minas Gerais, Brazil, is one of the most important karstic areas of the Brazilian Quaternary due to the faunistic diversity of living and extinct forms. Among them, some taxa remain poorly studied, as is the case of Calomys anoblepas Winge 1887. Despite the recent allocation of the taxon within Juliomys, its description and morphological analysis are condensed, based on comparative few specimens and on few informative characters. In this study, we investigate characters proposed to distinguish species of Juliomys, and reevaluate the taxonomic status of the fossil Juliomys anoblepas. We analyzed 80 cranio-dental morphological characters in 233 specimens represented by the four species currently recognized: J. pictipes (Osgood 1933), J. rimofrons Oliveira & Bonvicino 2002, J. ossitenuis Costa, Pavan, Leite & Fagundes 2007, and J. ximenezi Christoff, Vieira, Oliveira, Gonçalves, Valiati & Tomasi 2016. We also performed principal component analysis on eight craniodental measurements available for the J. anoblepas hypodigm. The review of morphological systems and the evaluation of the characters used in the literature revealed that there are no diagnostic characters in the anterior portion of the skull and in the molar series of Juliomys, being difficult to differentiate the fossil from the other living species. Only six qualitative characters were variable and applicable to the hypodigm of J. anoblepas. Characters are polymorphic, invariable, or the fossil is not sufficiently complete to determinate its states. The taxon could not be morphometrically differentiated from J. pictipes and J. ossitenuis. Based on the results presented herein, we consider J. anoblepas as a nomen dubium and restrict its name to the taxon’s hypodigm. 

scholarly journals Morphological Variability of Pterocarpus erinaceus Poir. in Togo

2020 ◽  
Vol 2020 ◽  
pp. 1-16
Author(s):  
Benziwa N. Johnson ◽  
Marie Luce A. Quashie ◽  
Kossi Adjonou ◽  
Kossi N. Segla ◽  
Adzo D. Kokutse ◽  
...  
Keyword(s):  
Principal Component Analysis ◽  
Morphological Variability ◽  
Principal Component ◽  
West African ◽  
Distribution Area ◽  
Terminal Leaflet ◽  
Forest Species ◽  
Morphological Descriptors ◽  
Pterocarpus Erinaceus ◽  
Relevant Variables

Pterocarpus erinaceus Poir. (Fabaceae), also called Vène or West African rosewood, is a multipurpose endemic forest species of Sahelo-Sudanian and Sudano-Guinean savannas and forests of West Africa. In Togo, the species is overexploited, which dangerously hinders its survival. The need and emergency of restoring declining stands, using seeds, or propagating material suggests an assessment of its morphological variability. The purpose of this study is to identify the discriminating morphological descriptors, allowing us to describe and also to characterize the species. Five provenances distributed over the whole geographical distribution area in Togo were evaluated for leaf (7 descriptors), fruit (4 descriptors), and seed (4 descriptors) traits. The coefficient of variation (CV) and the principal component analysis (PCA) are used to assess the variability among tree populations. Results show that the discriminating morphological descriptors for P. erinaceus in Togo are the width of the leaf and the terminal leaflet, the length and the width of the fruit, and length and the weight of the seed. These six main relevant variables allow us to discriminate three morphological groups of P. erinaceus population.

Further Observation on Study Difficulty in University Students Including ‘Syllabus-Boundness’

1976 ◽  
Vol 129 (6) ◽  
pp. 598-603 ◽  
Author(s):  
C. J. Lucas ◽  
Sidney Grown ◽  
Peter Stringer ◽  
Saradha Supramaniam
Keyword(s):  
Principal Component Analysis ◽  
Academic Success ◽  
University Students ◽  
Negative Relationship ◽  
Principal Component ◽  
The Other ◽  
Control Group ◽  
Psychiatric Symptomatology ◽  
Significant Negative Relationship ◽  
Seeking Help

SummaryThe UCLS questionnaire, in a form modified to include a measure of syllabus-boundness, and a questionnaire to measure psychiatric symptomatology (the MHQ) were administered to two groups of students, one seeking help for emotional problems, the other a control group. Groups were compared on tests, test findings were inter-correlated, and scores were related to academic success. The UCLSQ is confirmed as a reliable research instrument. Principal component analysis again indicates a separation of psychoneurotic and motivational components of study difficulty. Syllabus-boundness (‘Sylbism’) emerges as a relatively independent trait, with a significant negative relationship to work satisfaction in both groups. MHQ, scores again show a positive correlation between phobic anxiety and academic attainment for patients.

scholarly journals Morphological variability of acorns and its taxonomic significance in Quercus. from Turkey

2015 ◽  
Vol 43 (3) ◽  
pp. 293-299 ◽  
Author(s):  
Y Bakis ◽  
MT Babaç
Keyword(s):  
Principal Component Analysis ◽  
Morphological Variability ◽  
Morphological Characteristics ◽  
Principal Component ◽  
Component Analysis ◽  
Morphological Characters ◽  
Taxonomic Significance ◽  
Morphological Variations ◽  
Quercus Species ◽  
Different Populations

Morphological variations of acorn among and within the groups of Quercus species were studied. A total of 617 acorns belonging to 14 species representing all 3 sections of Quercus L. (Fagaceae) in Turkey were examined in this study. Specimens were collected from 47 different populations over both Anatolian and Thrace part of Turkey. Principal component analysis was used to analyze the morphological characteristics of acorns. Results obtained from this study demonstrate the use of morphological characters in differentiating the taxa of Quercus and Cerris sections studied. Another important finding is the introgression among the acorns of species within Quercus section DOI: http://dx.doi.org/10.3329/bjb.v43i3.21601 Bangladesh J. Bot. 43(3): 293-299, 2014 (December)

The structure of Estonian personal values: a lexical approach

2002 ◽  
Vol 16 (3) ◽  
pp. 221-235 ◽  
Author(s):  
Toivo Aavik ◽  
Jüri Allik
Keyword(s):  
Principal Component Analysis ◽  
Personal Values ◽  
General Structure ◽  
Principal Component ◽  
Higher Order ◽  
The Self ◽  
The Other ◽  
Two Dimensional ◽  
Lexical Approach ◽  
Estonian Language

The main purpose of this paper is to investigate the variety of value describing words and interrelation of value categories in the Estonian language. To accomplish this aim, a psycholexical approach was adopted, during which a set of 560 value‐related words was selected from the Estonian Orthological Dictionary and the results were compared with the Schwartz Values Survey (SVS). When principal‐component analysis was applied on the self‐ratings of a reduced list of 78 value‐related words, six factors emerged and were labelled as benevolence, self‐enhancement, broadmindedness, hedonism, conservatism, and self‐realization. However, all these themes are interrelated and load on a singular secondary dimension. The constructs measured by SVS and the value categories in Estonian were only partially interchangeable; moderate correlations imply an imperfect correspondence: each theme was related to many categories on the other questionnaire. However, a significant general structure refers to the same two‐dimensional level of higher‐order values described by Schwartz in 1992. Copyright © 2002 John Wiley & Sons, Ltd.

scholarly journals Comparative analysis of shell occupation by two southern populations of the hermit crab Loxopagurus loxochelis (Decapoda, Diogenidae)

2012 ◽  
Vol 60 (3) ◽  
pp. 299-310 ◽  
Author(s):  
Luciane Ayres-Peres ◽  
Aline Ferreira Quadros ◽  
Fernando L. Mantelatto
Keyword(s):  
Principal Component Analysis ◽  
Comparative Analysis ◽  
Hermit Crab ◽  
Regression Tree ◽  
Principal Component ◽  
Hermit Crabs ◽  
Pca Analysis ◽  
Internal Volume ◽  
The Relationship ◽  
Two Populations

The present study aimed to comparatively verify the relation between the hermit crabs and the shells they use in two populations of Loxopagurus loxochelis. Samples were collected monthly from July 2002 to June 2003, at Caraguatatuba and Ubatuba Bay, São Paulo, Brazil. The animals sampled had their sex identified, were weighed and measured; their shells were identified, measured and weighed, and their internal volume determined. To relate the hermit crab's characteristics and the shells' variables, principal component analysis (PCA) and a regression tree were used. According to the PCA analysis, the three gastropod shells most frequently used by L. loxochelis varied in size. The regression tree successfully explained the relationship between the hermit crab's characteristics and the internal volume of the inhabited shell. It can be inferred that the relationship between the morphometry of an individual hermit crab and its shell is not straightforward and it is impossible to explain only on the basis of direct correlations between the body's and the shell's attributes. Several factors (such as the morphometry and the availability of the shell, environmental conditions and inter- and intraspecific competition) interact and seem to be taken into consideration by the hermit crabs when they choose a shell, resulting in the diversified pattern of shell occupancy shown here and elsewhere.

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