Ecology of Foliicolous Lichens at the ‘Botarrama’ Trail (Costa Rica), a Neotropical Rainforest. IV. Species Associations, their Salient Features and Their Dependence on Environmental Variables

1999 ◽  
Vol 31 (3) ◽  
pp. 269-289 ◽  
Author(s):  
Robert Lücking
Keyword(s):  
Principal Component Analysis ◽  
Environmental Variables ◽  
Temporal Structure ◽  
Principal Component ◽  
The Other ◽  
Mode Of Reproduction ◽  
Neotropical Rainforest ◽  
Light Gaps ◽  
Shape And Size ◽  
Light Gap

AbstractA community ecology approach using an association of species test and a principal component analysis resulted in the recognition of two major and two minor foliicolous lichen communities in a neotropical rainforest. The major communities arc governed by microclimatic factors, one characteristic of the shady understorcy and the other confined to light gaps. The minor communities are due to subtle phorophyte preferences towards palm and dicot leaves. The shady understorey community is dominated by the families Anhoniaceae, Opegraphaceae, Tnchoihdiaceae and Pilocarpaceae, which predominantly have Phycepeltis as their phycobiont, thin thalli, abundant sexual reproduction, small ascospores produced in high numbers, and pyenidial conidiomata. The light-gap community is mainly composed of the families Gomphillaceae and Ectolechiaceae, with Trebouxia as their phycobiont, thickly crystalline or whitish, dispersed thalli, frequent asexual reproduction, large ascospores produced in low numbers, and specialized campylidia and hyphophores as conidiomata. Phycobiont, thallus structure, and the mode of reproduction are considered as adaptations to different microsites, whereas the shape and size of ascospores and conidia seem to be of less importance. The foliicolous lichen communities reflect the spatial and temporal structure of the forest, in particular the continuity of the shady understorey in comparison to the discontinuity of the light gaps. While the formation of the shady understorey community follows more deterministic patterns, the light-gap community exhibits high stochasticity.

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 Antlers Characterization for Identification of Deer Species (Family Cervidae) in Indonesia

2019 ◽  
Vol 4 (3) ◽  
pp. 97
Author(s):  
Donan Satria Yudha ◽  
M Zulfiqar Meizar Pratama ◽  
Rury Eprilurahman
Keyword(s):  
Principal Component Analysis ◽  
Principal Component ◽  
Morphological Characters ◽  
Main Beam ◽  
Size Measurement ◽  
Economic Values ◽  
Deer Species ◽  
Unique Character ◽  
Long Time ◽  
Shape And Size

There are five species of deer (family Cervidae) living in Indonesia today. Male deer possesses antlers, a unique character of male deer. Antlers have economic values for quite a long time. Antler’s growth is influenced by several factors, therefore each species of deer have its own unique antlers’ shape and size. Antler’s identification usually relies on size measurement and overall shape of complete antlers which still attach to the skull. It is difficult to identify shed, broken or individual antler. The purpose of the research is to understand antlers’ morphological characters on each species to become diagnostic characters. Specimens analysed were collections of LIPI and were analysed with Principal Component Analysis (PCA) using PAST3 software. The results showed each species of deer having their own unique antlers’ character, and so it can be used to determine the species of Indonesian deer. The important structures for identification are relief, pedicle, brow, bez, and main beam.

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.

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. 

Spatial modelling of soil organic carbon stocks with combined principal component analysis and geographically weighted regression

2018 ◽  
Vol 156 (6) ◽  
pp. 774-784 ◽  
Author(s):  
Long Guo ◽  
Mei Luo ◽  
Chengsi Zhangyang ◽  
Chen Zeng ◽  
Shanqin Wang ◽  
...  
Keyword(s):  
Principal Component Analysis ◽  
Organic Carbon ◽  
Soil Organic Carbon ◽  
Geographically Weighted Regression ◽  
Environmental Variables ◽  
Prediction Models ◽  
Principal Component ◽  
Weighted Regression ◽  
Auxiliary Variables ◽  
Soc Stocks

AbstractWith the development of remote sensing and geostatistical technology, complex environmental variables are increasingly easily quantified and applied in modelling soil organic carbon (SOC). However, this emphasizes data redundancy and multicollinearity problems adding to the difficulty in selecting dominant influential auxiliary variables and uncertainty in estimating SOC stocks. The current paper considers the spatial characteristics of SOC density (SOCD) to construct prediction models of SOCD on the basis of reducing the data dimensionality and complexity using the principal component analysis (PCA) method. A total of 260 topsoil samples were collected from Chahe town, China. Eight environmental variables (elevation, aspect, slope, normalized difference vegetation index, normalized difference moisture index, nearest distance to construction area and road, and land use degree comprehensive index) were pre-analysed by PCA and then extracted as the main principal component variables to construct prediction models. Two geostatistical approaches (ordinary kriging and ordinary co-kriging) and two regression approaches (ordinary least squares and geographically weighted regression (GWR)) were used to estimate SOCD. Results showed that PCA played an important role in reducing the redundancy and multicollinearity of the auxiliary variables and GWR achieved the highest prediction accuracy in these four models. GWR considered not only the spatial characteristics of SOCD but also the related valuable information of the auxiliary attributes. In summary, PCA-GWR is a promising spatial method used here to predict SOC stocks.

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.

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 Evaluation, Effect of Whitening Agents on Physico-Chemical and Functional Properties of Sardine Surimi (Sardina pilchardus)

2021 ◽  
pp. 74-89
Author(s):  
Imen Zaghbib ◽  
Soumaya Arafa ◽  
Hassouna Mnasser
Keyword(s):  
Hydrogen Peroxide ◽  
Principal Component Analysis ◽  
Calcium Carbonate ◽  
Sodium Bicarbonate ◽  
Functional Properties ◽  
Principal Component ◽  
Textural Properties ◽  
The Other ◽  
Sardina Pilchardus ◽  
Whitening Agent

The effects of hydrogen peroxide (H2O2), sodium bicarbonate (NaHCO3) and calcium carbonate (CaCO3) treatments on the colour and textural properties of sardine surimi (Sardina pilchardus) were studied. Principal Component Analysis (PCA) was applied in order to investigate their effects and to determine the optimum whitening agents used. Addition of CaCO3 and H2O2 significantly improved whiteness of surimi in comparison to NaHCO3 treatments (p < 0.05). Some textural damage and a reduction in WHC values were observed for surimi treated withH2O2 and NaHCO3 (p < 0.05). PCA biplot showed that 1.5% CaCO3 tended to result in improved whiteness, WHC and textural properties since 1.5% CaCO3 sample sits closer to these functional properties vector lines than the other treatments. Whereas, 2.5% H2O2 had positively affected only the whiteness parameter. Results indicated that treating mince with the appropriate type and concentration of whitening agent can improve the functional properties of surimi, particularly from fish species with darker meat such as sardine. Aims: In order to improve whiteness and functional properties of sardine surimi (Sardina pilchardus), the effects of hydrogen peroxide (H2O2), sodium bicarbonate (NaHCO3) and calcium carbonate (CaCO3) treatments were studied. Principal Component Analysis (PCA) was applied in order to investigate their effects and to determine the optimum whitening agents used. Study Design: Experimental Research Design Place and Duration of Study: Research Unit “Biopreservation and Valorisation of Agro-Food Products” of the Higher Graduate School of Food Industry of Tunisia. The study was conducted in 3 months. Methodology: Sardine surimi samples were prepared with different treatments at different concentrations: calcium carbonate (CaCO3), hydrogen peroxide (H2O2) and sodium bicarbonate (NaHCO3). Proximate composition, total pigment, whiteness, water holding capacity and textural properties were investigated. Optimal levels of each whitening agent were determined using PCA. Results: Addition of CaCO3 and H2O2 significantly improved whiteness of surimi in comparison to NaHCO3 treatments (p < 0.05). Some textural damage and a reduction in WHC values were observed for surimi treated withH2O2 and NaHCO3 (p < 0.05). PCA biplot showed that 1.5% CaCO3 tended to result in improved whiteness, WHC and textural properties since 1.5% CaCO3 sample sits closer to these functional properties vector lines than the other treatments. Whereas, 2.5% H2O2 had positively affected only the whiteness parameter. Conclusion: Results indicated that treating mince with the appropriate type and concentration of whitening agent can improve the functional properties of surimi, particularly from fish species with darker meat such as sardine.

scholarly journals Ranking Cultivated Blueberry for Mummy Berry Blight and Fruit Infection Incidence Using Resampling and Principal Components Analysis

HortScience ◽  
2010 ◽  
Vol 45 (8) ◽  
pp. 1205-1210 ◽  
Author(s):  
Mark K. Ehlenfeldt ◽  
James J. Polashock ◽  
Allan W. Stretch ◽  
Matthew Kramer
Keyword(s):  
Principal Component Analysis ◽  
Principal Component ◽  
The Other ◽  
Breeding Strategies ◽  
Relative Resistance ◽  
Term Variation ◽  
Components Analysis ◽  
Infection Stage ◽  
Selection Of

Mummy berry disease of blueberry has two distinct phases: a blighting phase that infects emerging shoots and leaves early in the spring and a flower infection phase that ultimately leads to infected (mummified) fruit. Cultivated blueberry (Vaccinium spp.) genotypes that are resistant to one phase are not necessarily resistant to the other phase. The resistance of cultivated blueberry (Vaccinium spp.) genotypes to each phase of the disease is different. A large number of cultivars were screened for resistance to each phase. Cultivar standards (cultivars with well-documented responses to the disease) were used in the screening to evaluate long-term variation and aid comparisons across years. Using nine standards for the blight phase, 125 cultivars were tested and ranked for relative resistance using a ranking system based on resampling and principal component analysis. Similarly, using six standards for the flower/fruit infection stage, 110 blueberry cultivars were tested and ranked for relative resistance. Cultivar rankings show that lowbush cultivars and other types possessing high percentages of lowbush germplasm are generally more resistant to both phases of the disease. Among highbush cultivars, Bluejay is reliably resistant to both phases. Documentation of resistance to each phase will allow selection of cultivars for planting in affected areas and will facilitate the development of breeding strategies to produce cultivars with superior resistance.

scholarly journals Evaluation of the Quality of Chinese and Vietnamese Cassia Using LC-MS and Multivariate Analysis

2013 ◽  
Vol 8 (1) ◽  
pp. 1934578X1300800
Author(s):  
Ken Tanaka ◽  
Feng Li ◽  
Yasuhiro Tezuka ◽  
Shiro Watanabe ◽  
Nobuo Kawahara ◽  
...  
Keyword(s):  
Principal Component Analysis ◽  
Multivariate Analysis ◽  
Chemical Composition ◽  
Herbal Medicine ◽  
Principal Component ◽  
The Other ◽  
Chemical Composition Of Water ◽  
Different Types ◽  
Marker Compounds

In the present study, the chemical composition of water extracts of Chinese and Vietnamese cassia (Cinnamomum cassia) were compared using multivariate analysis of LC-MS data. By principal component analysis of the LC-MS data, 6 compounds, cinnzeylanine (1), cinnzeylanol (2), anhydrocinnzeylanol (3), cinncasinol A (4), epicatechin (5) and procyanidin B2 (6), were identified as the marker compounds to characterize Chinese and Vietnamese cassia. It was clarified that Chinese cassia contains relatively larger amounts of epicatechin and procyanidin B2. On the other hand, Vietnamese cassia is characterized by a relatively larger amount of diterpenes. As catechin derivatives and diterpenes have different types of activity, it is important to choose the cassia that best suits the product for which it is to be used, whether in food or in herbal medicine.

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