Consulta: subjectFacets:"Principal component analysis"
Registros recuperados: 72
Data/hora: 13/06/2024 06:40:02

Identificación de áreas degradadas, por erosión en cárcavas, en el eje neovolcánico mexicano.
Provedor de dados: 32
Autores: Zamora Tirado, Paula Erika.
El presente el trabajo se desarrolló en la provincia fisiográfica Eje Volcánico Mexicano donde los procesos de erosión por cárcavas son frecuentes y relevantes, ocasionado importantes pérdidas económicas y ambientales, con el objetivo de caracterizar los parámetros ambientales que influyen en la formación de cárcavas, como: material parental, suelo, fase física, erosionabilidad, pendiente, longitud de pendiente, orientación, curvatura horizontal y vertical, índice de posición topográfica, índice topográfico de humedad, índice de Fournier, índice de vegetación ajustada al suelo y distancia a estructuras volcánicas. Se realizó un Análisis de Componentes Principales (ACP) con el propósito de identificar las variables que mejor expliquen la formación de...
Palavras-chave: Análisis de componentes principales; Análisis de máxima verosimilitud; Erosión en cárcavas; Modelación en cárcavas; Variables ambientales; Principal component analysis; Maximum likelihood analysis; Gully; Ravine modeling; Environmental variables; Edafología; Maestría.
Ano: 2014
URL: http://hdl.handle.net/10521/2372

The bacterial community structure in an alkaline saline soil spiked with anthracene
Provedor de dados: 69
Autores: Castro-Silva,Carolina; Ruíz-Valdiviezo,Víctor M; Valenzuela-Encinas,César; Alcántara-Hernández,Rocio J; Navarro-Noya,Yendi E; Vázquez-Núñez,Edgar; Luna-Guido,Marco; Marsch,Rodolfo; Dendooven,Luc.
Background: The application of polycyclic aromatic hydrocarbons (PAHs) will affect the bacterial community structure as some groups will be favoured and others not. An alkaline saline soil with electrolytic conductivity (EC) 56 dS m-1 was spiked with anthracene and acetone while their effect on bacterial community structure was investigated. Results: The percentages of Acidobacteria and Actinobacteria decreased over time, while the percentage of Proteobacteria, mostly Xanthomonadales, increased. The percentage of the phylotypes belonging to the Nocardioides, Rhodococcus and Streptomyces, known degraders of PAHs, was larger in the anthracene-amended soil than in the acetone-amended and unamended soil at day 14. The phylotypes belonging to the genera...
Tipo: Journal article
Palavras-chave: C dynamics; N mineralization; Phylogenetic analysis; Polycyclic aromatic hydrocarbons; Principal component analysis; UniFrac.
Ano: 2013
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582013000500010

BEHAVIOR OF BROILERS UNDER THE INFLUENCE OF LED LIGHTING AND MICROMETEOROLOGICAL ELEMENTS
Provedor de dados: 70
Autores: Rodrigues,Tatiana P. N. da S.; Pandorfi,Héliton; Guiselini,Cristiane; Almeida,Gledson L. P. de; Morrill,Waldirene B. B.
ABSTRACT The objective of this research was to analyze the differences between the food behaviors observed under the factors of production environment, sex and lighting system, using stochastic tools of multivariate analysis. As for the thermal characteristics of the environment, air temperature (T, °C), enthalpy (H, kJ kg-1), and black globe temperature and humidity index (BGTHI) showed high positive correlation with each other and strong negative correlation with relative humidity (RH, %). The “male drinking” behavior was positively associated with thermal characteristics of the environment in the three periods of the day, that is, the act of drinking more water would be a way to alleviate thermal stress. Birds subjected to red LED showed a strong...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Animal welfare; Broiler farming; Lighting system; Principal component analysis; Thermal comfort.
Ano: 2020
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-69162020000300272

CLASSIFICATION OF ROBUSTA COFFEE FRUITS AT DIFFERENT MATURATION STAGES USING COLORIMETRIC CHARACTERISTICS
Provedor de dados: 70
Autores: Costa,Anderson G.; Sousa,Daniela A. G. de; Paes,Juliana L.; Cunha,João P. B.; Oliveira,Marcus V. M. de.
ABSTRACT Coffee growers who produce the robusta species (Conilon) have sought to increase productivity and drink quality by improving production techniques. Artificial vision systems can assist in increasing the efficiency of operations associated with crop management. This study aimed to obtain colorimetric characteristics of robusta coffee fruits at different stages of maturity and use them for classifying fruits from digital images. A digital camera with spectral resolution in the visible was used to acquire images from 60 samples of coffee fruits at the green, cherry, and over-ripe stages of maturity. Colorimetric variables were extracted from the RGB, HIS, and L*a*b* color models and correlated with the physicochemical attributes of the fruits. The...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Artificial vision systems; Coffea canephora; Principal component analysis.
Ano: 2020
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-69162020000400518

Multivariate statistical analysis to support the minimum streamflow regionalization
Provedor de dados: 70
Autores: Elesbon,Abrahão A. A.; Silva,Demetrius D. da; Sediyama,Gilberto C.; Guedes,Hugo A. S; Ribeiro,Carlos A. A. S.; Ribeiro,Celso B. de M.
ABSTRACT This study aimed to develop a methodology based on multivariate statistical analysis of principal components and cluster analysis, in order to identify the most representative variables in studies of minimum streamflow regionalization, and to optimize the identification of the hydrologically homogeneous regions for the Doce river basin. Ten variables were used, referring to the river basin climatic and morphometric characteristics. These variables were individualized for each of the 61 gauging stations. Three dependent variables that are indicative of minimum streamflow (Q7,10, Q90 and Q95). And seven independent variables that concern to climatic and morphometric characteristics of the basin (total annual rainfall – Pa; total semiannual rainfall...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Principal component analysis; Cluster analysis; Homogeneous regions.
Ano: 2015
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-69162015000500838

Genomic variation and population structure detected by single nucleotide polymorphism arrays in Corriedale, Merino and Creole sheep
Provedor de dados: 74
Autores: Grasso,Andrés N; Goldberg,Virginia; Navajas,Elly A; Iriarte,Wanda; Gimeno,Diego; Aguilar,Ignacio; Medrano,Juan F; Rincón,Gonzalo; Ciappesoni,Gabriel.
The aim of this study was to investigate the genetic diversity within and among three breeds of sheep: Corriedale, Merino and Creole. Sheep from the three breeds (Merino n = 110, Corriedale n = 108 and Creole n = 10) were genotyped using the Illumina Ovine SNP50 beadchip®. Genetic diversity was evaluated by comparing the minor allele frequency (MAF) among breeds. Population structure and genetic differentiation were assessed using STRUCTURE software, principal component analysis (PCA) and fixation index (F ST). Fixed markers (MAF = 0) that were different among breeds were identified as specific breed markers. Using a subset of 18,181 single nucleotide polymorphisms (SNPs), PCA and STUCTURE analysis were able to explain population stratification within...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Allele frequencies breed composition; Fixation index; Ovine SNP50; Population stratification; Principal component analysis.
Ano: 2014
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572014000300011

Genetic differentiation and geographical Relationship of Asian barley landraces using SSRs
Provedor de dados: 74
Autores: Naeem,Rehan; Dahleen,Lynn; Mirza,Bushra.
Genetic diversity in 403 morphologically distinct landraces of barley (Hordeum vulgare L. subsp. vulgare) originating from seven geographical zones of Asia was studied using simple sequence repeat (SSR) markers from regions of medium to high recombination in the barley genome. The seven polymorphic SSR markers representing each of the chromosomes chosen for the study revealed a high level of allelic diversity among the landraces. Genetic richness was highest in those from India, followed by Pakistan while it was lowest for Uzbekistan and Turkmenistan. Out of the 50 alleles detected, 15 were unique to a geographic region. Genetic diversity was highest for landraces from Pakistan (0.70 ± 0.06) and lowest for those from Uzbekistan (0.18 ± 0.17). Likewise,...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Cluster analysis; Genetic diversity; Geographical differentiation; Hordeum vulgare; Principal component analysis.
Ano: 2011
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572011000200017

Aplicativo para análise de componentes principais.
Provedor de dados: 14
Autores: PALUMBO, F. V. P.; CARVALHO, J. R. P. de; MOURA, M. F.
Análise por componentes principais. Entrada de dados para o aplicativo: Procedimento. Opções do aplicativo. Especificação de algoritmos: Descrição de método. Cálculo usando a matriz de variâncias e covariâncias(S). Cálculo usando a matriz de correlação (R). Cálculo usando a Matriz Parcial.
Tipo: Comunicado Técnico (INFOTECA-E)
Palavras-chave: Algoritmos; Software NTIA; Análise de componentes principais; Análise multivariada; Algorithms; Computer software; Principal component analysis; Multivariate analysis.
Ano: 1999
URL: http://www.infoteca.cnptia.embrapa.br/infoteca/handle/doc/6923

Análise de agrupamento de dados de expressão gênica na Rede Genômica Animal.
Provedor de dados: 14
Autores: HIGA, R. H.; GIACHETTO, P. F.; YAMAGISHI, M. E. B.; IBELLI, A. M. G.; REGITANO, L. C. de A.; CARDOSO, F. F.
O objetivo deste trabalho é apresentar a análise de agrupamento de dados de expressão gênica, conforme realizada no escopo da ?Rede Genômica Animal?. Na seção 2, são apresentados conceitos básicos sobre análises de agrupamento. Em particular, os algoritmos de agrupamento utilizados nessas análises compreendem aqueles mais conhecidos, como k-means, SOM e agrupamento hierárquico. A plataforma de análise escolhida para realização das análises de agrupamento na ?Rede Genômica Animal? é o ambiente de análise estatística R (R DEVELOPMENT CORE TEAM, 2010) e o projeto Bioconductor (GENTLEMAN et al., 2004). Assim, na seção 3 é apresentado um exemplo completo de análise de agrupamento e seu respectivo script R.
Tipo: Comunicado Técnico (INFOTECA-E)
Palavras-chave: Agrupamento de dados; Expressão gênica; Rede Genômica Animal; Análise de componentes principais - PCA.; Análise Estatística.; Gene expression; Algorithms; Statistical analysis; Principal component analysis.
Ano: 2010
URL: http://www.infoteca.cnptia.embrapa.br/infoteca/handle/doc/883623

Fluctuations d'abondance de l'ichtyoplancton sur une zone frontale cotiere (Golfe de Gascogne: Baie d'Audierne)
Provedor de dados: 5
Autores: Camus, Patrick; Delpech, Jean-paul; Omnes, Marie-helene; Mastail, Max.
A two years ichthyoplankton sampling program over an eight station network on each side of a coastal tidal front was conducted twice a month during neap tides. A principal component analysis was performed on the data (taxa and observations) which were segregated during the summer into two groups of taxa related to two groups of stations belonging to two different hydrodynamical areas. In July and August 1980 during a tide cycle, zooplankton was investigated at two stations in the stratified and transitional area. Periodic fluctuations of meroplanktonic taxa correlated to the movement of the front induced by the tide were observed.
Tipo: Text
Palavras-chave: Ichthyoplancton; Front; Golfe de Gascogne; Analyse en composantes principales; Ichthyoplankton; Tidal front; Bay of Biscay; Principal component analysis.
Ano: 1983
URL: http://archimer.ifremer.fr/doc/00069/17991/15525.pdf

Estimation and propagation of uncertainties associated with paleomagnetic directions
Provedor de dados: 5
Autores: Heslop, David; Roberts, Andrew P.
Principal component analysis (PCA) is a well-established technique in paleomagnetism and provides a means to estimate magnetic remanence directions from univectorial segments of stepwise demagnetization data. Derived directions constrain past geomagnetic field behavior and form the foundation of chronological and tectonic reconstructions. PCA of isolated remanence segments relies on estimates of the segment mean and covariance matrix, which can carry large uncertainties given the relatively small number of demagnetization data points used to characterize individual specimens. Traditional PCA does not, however, lend itself to quantification of these uncertainties, and inferences drawn from paleomagnetic reconstructions suffer from an inability to propagate...
Tipo: Text
Palavras-chave: Paleomagnetism; Directional uncertainty; Principal component analysis.
Ano: 2016
URL: https://archimer.ifremer.fr/doc/00421/53255/54707.pdf

Origin of fecal contamination in waters from contrasted areas: Stanols as Microbial Source Tracking markers
Provedor de dados: 5
Autores: Derrien, M.; Jarde, E.; Gruau, G.; Pourcher, A. M.; Gourmelon, Michele; Jadas-hecart, Alain; Wickmann, A. C. Pierson.
Improving the microbiological quality of coastal and river waters relies on the development of reliable markers that are capable of determining sources of fecal pollution. Recently, a principal component analysis (PCA) method based on six stanol compounds (i.e. 5 beta-cholestan-3 beta-ol (coprostanol), 5 beta-cholestan-3 alpha-ol (epicoprostanol), 24-methyl-5 alpha-cholestan-3 beta-ol (campestanol), 24-ethyl-5 alpha-cholestan-3 beta-ol (sitostanol), 24-ethyl-5 beta-cholestan-3 beta-ol (24-ethylcoprostanol) and 24-ethyl-5 beta-cholestan-3 alpha-ol (24-ethylepicoprostanol)) was shown to be suitable for distinguishing between porcine and bovine feces. In this study, we tested if this PCA method, using the above six stanols, could be used as a tool in...
Tipo: Text
Palavras-chave: Stanols; Microbial Source Tracking; Principal component analysis; Microbial markers.
Ano: 2012
URL: http://archimer.ifremer.fr/doc/00090/20133/17829.pdf

Selecting soil quality indicators for different soil management systems in the Brazilian Cerrado
Provedor de dados: 86
Autores: Stefanoski,Diane Cristina; Figueiredo,Cícero Célio de; Santos,Glenio Guimarães; Marchão,Robélio Leandro.
Abstract The objective of this work was to assess soil quality indicators obtained with different datasets to compare soil management systems in the Brazilian Cerrado. Three criteria were used to select soil physical, chemical, and biological indicators: the full set of indicators obtained, with 36 parameters, for which all the physical, chemical, and biological soil properties were determined; a subset of indicators selected by principal component analysis (20 parameters); and a subset of indicators with some frequency of use in the literature (16 parameters). These indicators were obtained from the following management systems: no-tillage, conventional tillage, and native cerrado vegetation. Soil samples were collected at 0.0-0.1-m soil depth, and soil...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: No-tillage; Principal component analysis; Soil functioning; Soil health; Soil management; Soil security.
Ano: 2016
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-204X2016000901643

Reproductive biology traits affecting productivity of sour cherry
Provedor de dados: 86
Autores: Aksic,Milica Fotiric; Rakonjac,Vera; Nikolic,Dragan; Zec,Gordan.
The objective of this work was to evaluate variability in reproductive biology traits and the correlation between them in genotypes of 'Oblačinska' sour cherry (Prunus cerasus). High genetic diversity was found in the 41 evaluated genotypes, and significant differences were observed among them for all studied traits: flowering time, pollen germination, number of fruiting branches, production of flower and fruit, number of flowers per bud, fruit set, and limb yield efficiency. The number of fruiting branches significantly influenced the number of flower and fruit, fruit set, and yield efficiency. In addition to number of fruiting branches, yield efficiency was positively correlated with fruit set and production of flower and fruit. Results from principal...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Prunus cerasus; Breeding; Genetic divergence; Pollen germination; Principal component analysis; Yield efficiency.
Ano: 2013
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-204X2013000100005

Chemical characteristics of grape juices from different cultivar and rootstock combinations
Provedor de dados: 86
Autores: Nassur,Rita de Cássia Mirela Resende; Pereira,Giuliano Elias; Alves,Juliana Alvarenga; Lima,Luiz Carlos de Oliveira.
The objective of this work was to evaluate the influence of different combinations of grape cultivars and rootstocks on chemical characteristics of grape juices. Six treatments were evaluated, consisting of combinations between the Isabel Precoce and BRS Cora grape cultivars and the 'IAC 766', 'IAC 313', and 'IAC 572' rootstocks. Approximately 10 L of juice were obtained per treatment. Analyses of color, total soluble solids content, pH, anthocyanins, total phenolics, total sugars, and quantification and identification of biogenic amines by HPLC were performed. Biogenic amines, such as putrescine, cadaverine, spermidine, and spermine, were found in all evaluated cultivars. By principal component analysis (PCA), treatments can be divided into two groups,...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Vitis labrusca; Anthocyanins; Biogenic amines; Phenolics; Principal component analysis.
Ano: 2014
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-204X2014000700540

Grouping sunflower genotypes for yield, oil content, and reaction to Alternaria leaf spot using GGE biplot
Provedor de dados: 86
Autores: Leite,Regina Maria Villas Bôas de Campos; Oliveira,Maria Cristina Neves de.
Abstract:The objective of this work was to evaluate the suitability of the multivariate method of principal component analysis (PCA) using the GGE biplot software for grouping sunflower genotypes for their reaction to Alternaria leaf spot disease (Alternariaster helianthi), and for their yield and oil content. Sixty-nine genotypes were evaluated for disease severity in the field, at the R3 growth stage, in seven growing seasons, in Londrina, in the state of Paraná, Brazil, using a diagrammatic scale developed for this disease. Yield and oil content were also evaluated. Data were standardized using the software Statistica, and GGE biplot was used for PCA and graphical display of data. The first two principal components explained 77.9% of the total...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Alternariaster helianthi; Helianthus annuus; Disease resistance; Principal component analysis.
Ano: 2015
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-204X2015000800649

Characterization of phosphate structures in biochar from swine bones
Provedor de dados: 86
Autores: Novotny,Etelvino Henrique; Auccaise,Ruben; Velloso,Marcia Helena Rodrigues; Corrêa,Juliano Corulli; Higarashi,Martha Mayumi; Abreu,Valéria Maria Nascimento; Rocha,José Dilcio; Kwapinski,Witold.
The objective of this work was to develop an alternative methodology to study and characterize the phosphate crystalline properties, directly associated with solubility and plant availability, in biochar from swine bones. Some phosphate symmetry properties of pyrolyzed swine bones were established, using solid state nuclear magnetic resonance spectroscopy, principal component analysis, and multivariate curve resolution analysis, on four pyrolyzed samples at different carbonization intensities. Increasing carbonization parameters (temperature or residence time) generates diverse phosphate structures, increasing their symmetry and decreasing the crossed polarizability of the pair ¹H-31P, producing phosphates with, probably, lower solubility than the ones...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Bone phosphate; Phosphate availability; Principal component analysis; Pyrolysis; Multivariedade curve resolution analysis; Soil fertility.
Ano: 2012
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-204X2012000500006

Phenotypic plasticity in a soybean cultivar with indeterminate growth type
Provedor de dados: 86
Autores: Balbinot Junior,Alvadi Antonio; Oliveira,Maria Cristina Neves de; Franchini,Julio Cezar; Debiasi,Henrique; Zucareli,Claudemir; Ferreira,André Sampaio; Werner,Flavia.
Abstract: The objective of this work was to evaluate how branch and stem variables contribute to grain yield in individual soybean (Glycine max) plants, cultivated at different planting densities, in a modern cultivar with indeterminate growth type. A field experiment was carried out during the 2013/2014 and 2014/2015 crop seasons, in a randomized complete block design with 12 replicates, using the cultivar NK7059 RR at four planting densities: 135, 235, 315, and 440 thousand plants per hectare. Grain yield per plant was evaluated and represented phenotypic plasticity, while the number of branches per plant, percentage of grain production in branches, and separate yield components from branches and stems were considered as the independent variables. The...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Glycine max; Plant density; Principal component analysis; Stepwise regression; Yield components.
Ano: 2018
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-204X2018000901038

Coliform density in oyster culture waters and its relationship with environmental factors
Provedor de dados: 86
Autores: Mignani,Luciene; Barbieri,Edison; Marques,Helcio Luis de Almeida; Oliveira,Ana Julia Fernandes Cardoso de.
The objective of this work was to evaluate the total and thermotolerant coliform densities in the oyster culture water of Cananeia, SP, Brazil, correlating these densities with environmental variables and tidal variations. Superficial water samples were collected in two tide conditions (spring and neap) from three areas of Cananéia municipality (Mandira, Itapitangui and Cooperostra). The three studied areas showed good conditions for the culture regarding coliform densities. The two tidal conditions differed significantly as to total coliform concentration; however, the same procedure was not performed for thermotolerant coliforms. No correlation was observed between water temperature, pH, and concentrations of total and thermotolerant coliforms. Coliform...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Crassostrea; Contamination; Microbiology; Principal component analysis; Total and thermotolerant coliforms.
Ano: 2013
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-204X2013000800007

Finding out Relationships Among Some Morpho-Biochemical Parameters of Christ's Thorn (Ziziphus spina-christi) under Drought and Salinity Stresses
Provedor de dados: 87
Autores: NEJAT,N.; SADEGHI,H.
ABSTRACT Taking into consideration that modeling and indicating relationship among traits and variables are among the most useful numerical techniques in the biological and botanical researches, and also undeniable impact of drought and salinity stresses, this research was implemented with the aim to consider change in relationship among the traits under separately drought and salinity stresses related to scarcely distributed medicinal plant called Christ thorn (Ziziphus spina-christi). A glass house experiment was implemented in controlled conditions at the College of Agriculture, Shiraz University, Shiraz, Iran. Five different water stress levels (irrigation at four, six, eight and 10 days intervals, compared to the unstressed control plants with every...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Salinity; Drought; Stepwise regressions; Principal component analysis; Cluster analysis.
Ano: 2016
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-83582016000400667

Variation of Cultivated Land Quantity in Coastal Cities and Its Driving Forces - A Case of Huludao City, China
Provedor de dados: 31
Autores: Li-juan,   Tang; Lei,   Lei; Ling,   Cao.
Variation of cultivated land quality in 10 major cities and its driving forces are introduced in recent 10 years. And economic development and population growth are the common driving forces for the reduction of cultivated land in coastal cities. Among them, economic development is the main driving force. Taking Huludao City as an example, driving factors of cultivated land variation in Huludao City are studied by Principal Component Analysis according to the relevant statistical data in the year 1998-2007. Result shows that in recent 10 years, total cultivated land area has increased in Huludao City, especially in the years 1998-2002. Driving force of cultivated land variation in Huludao City can be summarized as economic growth, population growth and...
Tipo: Journal Article
Palavras-chave: Coastal city; Cultivated land; Quantity variation; Driving force; Principal component analysis; China; Agribusiness.
Ano: 2010
URL: http://purl.umn.edu/93242

Does Social Capital Have a Role in Environmental Kuznets Curve? Spatial Panel Regression Approach
Provedor de dados: 31
Autores: Paudel,   Krishna P.; Zapata,   Hector O.; Schafer,   Mark J.; Marzoughi,   Hassan.
We advance a case for an inclusion of social capital in the environmental Kuznets curve analysis using highly disaggregated data on water pollution in Louisiana. A social capital index and other variables are used in parametric and spatial panel regression models to explain water pollution dynamics.
Tipo: Conference Paper or Presentation
Palavras-chave: Social capital; Principal component analysis; Environmental Kuznets curve; Spatial regression; Environmental Economics and Policy.
Ano: 2005
URL: http://purl.umn.edu/19457

Selected approaches of variables weighting in frame of composite indicator analysis
Provedor de dados: 31
Autores: Hlavsa,   Tomas.
Composite indicators are useful as tool for complex evaluation and aggregation of different variables of regional development. Variables which are aggregated in a composite indicator have first to be weighted. All variables may be given equal weights or they mea be given differing weights which reflect the significance, reliability or other characteristics of the underlying data. The weights given to different variables heavily influence the outcomes of the composite indicator. Aim of this paper is an evaluation of selected methods for weighting of particular variables in frame of composite indicator construction. Evaluation is verified on group of regional economic variables based on Strategy of regional development.
Tipo: Journal Article
Palavras-chave: Composite indicator; Region; Principal component analysis; Expert; Community/Rural/Urban Development; Research Methods/ Statistical Methods; GA; IN.
Ano: 2010
URL: http://purl.umn.edu/99082

Sustainable development ability of grain production in Sichuan Province
Provedor de dados: 31
Autores: Guo,   Hong; Zou,   Yi-xing; Xiong,   Guang.
We set up the evaluation index system of the sustainable development ability of grain production on the basis of the overall analysis of grain production trend in Sichuan Province. And then we evaluate the sustainable development ability of grain production from 1990 to 2006 in Sichuan Province by adopting the method of principal component analysis. Result shows that the sustainable development ability of grain production has improved steadily, but there are some hidden troubles such as frequently changes of grain yield and gradually decrease of total farmland. Cluster analysis method is used to study on the sustainable development ability of grain production of 21 cities of Sichuan Province in the year 2006. result shows that grain production levels in...
Tipo: Thesis or Dissertation
Palavras-chave: Sichuan Province; Grain production; Sustainable development; Principal component analysis; Cluster analysis; China; Community/Rural/Urban Development; Land Economics/Use; Resource /Energy Economics and Policy.
Ano: 2009
URL: http://purl.umn.edu/53481

Understanding farmers’ uptake of organic farming: An application of the theory of planned behaviour
Provedor de dados: 31
Autores: Lapple,   Doris; Kelley,   Hugh.
Whilst the adoption of agricultural techniques has received considerable attention in the literature, the ability and willingness of potential adopters to change their current farming system is often overlooked. This paper is concerned with the intention of conventional farmers to convert to organic farming by using the social-psychology theory of planned behaviour. Drivers and barriers of conversion to organic farming are identified by applying a belief based concept, which is confirmed using principal component analysis. In addition, accounting for heterogeneity regarding farmers‟ environmental attitudes masks considerable differences, notably at intention, attitudes and control perceptions. Overall, results reveal that conversion is indeed affected by...
Tipo: Conference Paper or Presentation
Palavras-chave: Organic farming; Theory of planned behaviour; Principal component analysis; Heterogeneity; Production Economics.
Ano: 2010
URL: http://purl.umn.edu/91949

Comprehensive Evaluation on Consumption Structure of Rural Residents with Principal Component Analysis in China
Provedor de dados: 31
Autores: Guan,   Lin; Li,   Chun lan; Zhang,   Bo.
In order to make analysis on consumption structure of rural residents, the paper make a principle component analysis on consumption expenditure per capita of rural residents in different areas of 2009 based on statistics of China statistical yearbook of 2010. Selecting a principal component, the paper arranges 31 provinces in China in order. Shanghai lists the 1st place with highest marks; coastal provinces in southeastern part, the Northeast, Beijing and Tianjin are at the top; the northern and central parts with Hebei, Shanxi, Hubei as representatives scores minus which is a little lower than that of average; the western part, such as Guizhou, Xizang, Ganssu and so on are in far behind. The paper also makes analysis on the consumption structure of rural...
Tipo: Journal Article
Palavras-chave: Rural residents; Consumption; Principal component analysis; China; Agribusiness.
Ano: 2011
URL: http://purl.umn.edu/113432

Economic difference in Ningbo area of China
Provedor de dados: 31
Autores: Pan,   Hua-ling.
Taking 6 counties and cities in Ningbo Area as the research units, this paper constructs the index system for evaluating the economic differences in Ningbo Area, and uses the principal component analysis method to analyze the economic differences in Ningbo Area.  Result shows that Ningbo economy as a whole is more developed, and there are significant differences among regional economy.  Economic development levels of Fenghua, Xiangshan and Ninghai districts are less developed, compared with those of Yinzhou, Yuyao and Cixi.
Tipo: Thesis or Dissertation
Palavras-chave: Economic differences; Principal component analysis; Ningbo Area; China; Financial Economics; Research Methods/ Statistical Methods.
Ano: 2009
URL: http://purl.umn.edu/53476

MULTIVARIATE PROCEDURES FOR IDENTIFYING RURAL LAND SUBMARKETS
Provedor de dados: 31
Autores: Kennedy,   Gary A.; Henning,   Steven A.; Vandeveer,   Lonnie R.; Dai,   Ming.
Research has developed empirical models and procedures for analyzing factors which influence rural land markets; however, there have been limited efforts in developing procedures for identifying rural land submarkets.  Principal component analysis is used here to detect the presence of multiple rural land submarkets. Cluster analysis is then used as a basis for identifying eight contiguous rural land submarkets in Louisiana. As opposed to single-attribute procedures that have been based largely on subjective judgment, multivariate procedures illustrated in this analysis provide a means for capturing the combined effects of physical and socioeconomic influences in delineating rural land submarkets.
Tipo: Journal Article
Palavras-chave: Cluster analysis; Land market analysis; Principal component analysis; Rural land submarkets; Land Economics/Use.
Ano: 1997
URL: http://purl.umn.edu/15066

Research on Rural Consumer Demand in Hebei Province Based on Principal Component Analysis
Provedor de dados: 31
Autores: Ma,   Hui-zi; Zhao,   Bang-hong; Xuan,   Yong-sheng.
By selecting me time sequence data concerning influencing factors of rural consumer demand in Hebei Province from 2000 to 2010, this paper uses the principal component analysis method in multiplex econometric statistical analysis, constructs the principal component of consumer demand in Hebei Province, conducts regression on the dependent variable of consumer spending per capita in Hebei Province and the principal component of consumer demand so as to get principal component regression, and then conducts quantitative and qualitative analysis on the principal component. The results show that total output value per capita (yuan), employment rate, and income gap, are correlative with rural residents' consumer demand in Hebei Province positively; consumer...
Tipo: Journal Article
Palavras-chave: Consumer demand; Principal component analysis; Regression analysis; Hebei Province; China; Agribusiness.
Ano: 2011
URL: http://purl.umn.edu/117256

Leading Economic Determinants of Foreign Trade Volume in Turkish Agriculture Sector
Provedor de dados: 31
Autores: Ozun,   Alper; Turk,   Mehmet.
We empirically analyze the main economic factors affecting the export and import levels in Turkish agriculture sector. Using monthly time series of certain domestic and international variables, we make three complementary analysis; namely, principal component analysis, causality and co-integration analysis, and multivariate GARCH analysis. The empirical findings point out the fact that foreign trade volume in Turkish agriculture sector is statistically in relation with agricultural production, consumer price index, market capitalization of the firms, and international agriculture prices.
Tipo: Article
Palavras-chave: Turkish agriculture sector; Foreign trade; Principal component analysis; Multivariate GARCH; Agricultural and Food Policy; Q14; 024; C5.
Ano: 2010
URL: http://purl.umn.edu/118579

Regional Agricultural Input-Output Model and Countermeasure for Production and Income Increase of Farmers in Southern Xinjiang, China
Provedor de dados: 31
Autores: Jiang,   Qing-song; Zhang,   Xing-ji.
Agricultural input and output status in southern Xinjiang, China is introduced, such as lack of agricultural input, low level of agricultural modernization, excessive fertilizer use, serious damage of environment, shortage of water resources, tremendous pressure on ecological balance, insignificant economic and social benefits of agricultural production in southern Xinjiang, agriculture remaining a weak industry, agricultural economy as the economic subject of southern Xinjiang, and backward economic development of southern Xinjiang. Taking the Aksu area as an example, according to the input and output data in the years 2002-2007, input-output model about regional agriculture of the southern Xinjiang is established by principal component analysis. DPS...
Tipo: Journal Article
Palavras-chave: Regional agriculture; Input-output model; Production and income increase; Principal component analysis; Econometric model，China; Agribusiness.
Ano: 2010
URL: http://purl.umn.edu/96049

Developing Poverty Assessment Tools Based on Principal Component Analysis: Results from Bangladesh, Kazakhstan, Uganda, and Peru
Provedor de dados: 31
Autores: Zeller,   Manfred; Houssou,   Nazaire; Alcaraz V.,   Gabriela; Schwarze,   Stefan; Johannsen,   Julia.
Developing accurate, yet operational poverty assessment tools to target the poorest households remains a challenge for applied policy research. This paper aims to develop poverty assessment tools for four countries: Bangladesh, Peru, Uganda, and Kazakhstan. The research applies the Principal Component Analysis (PCA) to seek the best set of variables that predict the household poverty status using easily measurable socio-economic indicators. Out of sample validations tests are performed to assess the prediction power of a tool. Finally, the PCA results are compared with those obtained from regressions models. In-sample estimation results suggest that the Quantile regression technique is the first best method in all four countries, except Kazakhstan. The PCA...
Tipo: Conference Paper or Presentation
Palavras-chave: Poverty assessment; Targeting; Principal component analysis; Bangladesh; Peru; Kazakhstan; Uganda; Food Security and Poverty; H5; Q14; I3.
Ano: 2006
URL: http://purl.umn.edu/25396

Classification of the EU countries labour markets
Provedor de dados: 31
Autores: Kaba,   Bohumil.
The objective of the paper is to classify the labour markets of the EU member states on the basis of selected employment and unemployment indicators. In order to achieve the study target, the adequate multivariate exploration procedures have been chosen. In the first part of processing original data, principal component analysis (PCA) was employed. PCA is a multivariate statistical procedure used to reduce the number of observed variables into a smaller number of uncorrelated variables with a minimum loss of information. Moreover, the PCA results can be used for effective ranking of the EU countries according to observed indicators of labour markets. This paper describes the crucial steps in PCA and procedure for ranking mentioned and it reviews how...
Tipo: Journal Article
Palavras-chave: Classification; Employment; Unemployment; Principal component analysis; Cluster; International Development; Public Economics; Research Methods/ Statistical Methods; GA; IN.
Ano: 2010
URL: http://purl.umn.edu/99227

Comparative analysis of micro-regions in the northern Great Plain Region
Provedor de dados: 31
Autores: Kiraly,   Zsolt; Szmolka,   Andrea.
Our short paper examines the region of the Northern Great Plain, mainly due to its disadvantaged situation. Comparative analysis of the micro-regions in this particular region was implemented to identify possible causes for differentiation between the micro-regions. Finding these causes would then help us find more effective ways to address regional inequalities, currently one of the central issues not only in Hungary but throughout Eastern Europe. The methods used for such analysis included statistical indicators, such as difference in migration rates, rate of unemployment, number of incorporated enterprises per 1000 inhabitants etc., as well as the principal component analysis and the currently applicable categorisation system for micro-regions. The...
Tipo: Journal Article
Palavras-chave: Regional differences; Micro-region; Principal component analysis; Területi különbségek; Kistérség; Főkomponens analízis; Community/Rural/Urban Development; Research Methods/ Statistical Methods.
Ano: 2009
URL: http://purl.umn.edu/92539

Operation Risk of Rural Cooperative Economic Organization Based on Principal Component Analysis –A Case of Sichuan Province, China
Provedor de dados: 31
Autores: Jia,   Xian-wei; Feng,   Ling.
Based on the previous research, a total of 10 risk indices are selected according to the specific situation in Sichuan Province, such as natural risk, resource constraint risk, internal management risk, capital risk, technical input and output risk, market risk, contract credit risk, property risk and policy support risk. According to the questionnaire survey by cooperative economic organization of Sichuan Province, principal component analysis is used to analyze the importance and influence degree of the operation risk of rural cooperative economic organization. Result shows that in the operation of cooperative economic organization, management risk has greater influence degree and importance degree, which should be paid special attention to. Capital,...
Tipo: Journal Article
Palavras-chave: Type of risk; Influence degree; Principal component analysis; Risk prevention; China; Agribusiness.
Ano: 2010
URL: http://purl.umn.edu/93643

Ranking and Clustering of the Economic Status of Rural Residents in 31 Provinces and Regions in China
Provedor de dados: 31
Autores: Tang,   Jun.
In order to rank and cluster the economic status of rural residents in 31 provinces, cities and autonomous regions, the MATLAB software is used and the component analysis and the cluster analysis are conducted on the data reflecting the economic status of each area. The results show that the provinces or cities with high comprehensive , scores are Shanghai Municipality, Beijing Municipality, Zhejiang Province, Jiangsu Province, Tianjin Municipality, Guangdong Province, Fujian Province, Shandong Province and Liaoning Province according to priority; the provinces or autonomous regions with low comprehensive scores are Gansu Province, Guizhou Province , Tibet, Uygur autonomous region and Yunnan Province. The economic status of rural residents in the 31...
Tipo: Journal Article
Palavras-chave: Economic status of rural residents; Principal component analysis; Cluster analysis; Economic development; China; Agribusiness.
Ano: 2010
URL: http://purl.umn.edu/102388

Study on Farmland Use Change and Driving Force in the High and Cold Areas in Northwest Yunnan-A Case Study of Ninglang Yi Autonomous County
Provedor de dados: 31
Autores: Luo,   Li; Yang,   Zi-sheng; Kang,   Yun-hai.
On the basis of overview of the study area, by analyzing the dynamic change of farmland in Ninglang County, we can find that the farmland area in this county tended to decrease from 1996 to 2008. According to the investigation data concerning land change provided by Bureau of Land and Resources in Ninglang County and socio-economic data provided by Bureau of Statistics in Ninglang County, we select 11 indices, such as total population, GDP, total output value of county and so on, coupled with SPSS statistical method, we adopt principal component analysis method to analyze driving force factors of farmland use change in the high and cold areas in Northwest Yunnan. The results show that the two factors of economic development and population growth are the...
Tipo: Journal Article
Palavras-chave: Changes of farmland; Driving force; Principal component analysis; Ninglang County; China; Agribusiness.
Ano: 2011
URL: http://purl.umn.edu/113427

Statistical Analysis of the Economic Level of Beijing, China
Provedor de dados: 31
Autores: Hao,   Chun-xu; Yang,   Li-fei; Wen,   Ya-li.
According to the data of economic development in Beijing from the year 1995 to 2007, relevant economic indices are selected to analyze the economic development level of Beijing by the Principal Component Analysis Method. Result shows that the national economy maintains high, sustainable and stable development in the years 1995-2007. Both the primary and secondary industry output values have increased year by year; and the tertiary industry output value has grown rapidly. The annual gross domestic product, the output value of tertiary industry, and the total retail sales of consumer goods have the greatest impact on economic level of Beijing. Output value of secondary industry is the growth ability factor in economic environment. Empirical analysis shows...
Tipo: Journal Article
Palavras-chave: Economic level; Principal component analysis; SPSS statistical software; China; Agribusiness.
Ano: 2009
URL: http://purl.umn.edu/93459

Allocation of New Construction Land Based on Land Competitiveness Evaluation
Provedor de dados: 31
Autores: Huo,   Guang-hui; Huang,   Liang-xiang.
Connotation of land competitiveness is expatiated from both the narrow sense and broad sense. Evaluation index system of land competitiveness is established according to the 2008 China Statistical Yearbook and 2008 China Land Resources Statistical Yearbook. Efficiency Coefficient Method and Principal Component Analysis Method are used to evaluate the land competitiveness of 31 provincial units in China. Result shows that in the year 2007, land competitiveness gradually decreases from southeast to northwest. The land competitiveness and GDP per unit land have significant negative correlation. The rank of approved new construction land has low positive correlation with the rank of land competitiveness in China. This indicates that there is little correlation...
Tipo: Journal Article
Palavras-chave: Land competitiveness; New construction land; Pareto Optimality; Efficiency coefficient method; Principal component analysis; China; Agribusiness.
Ano: 2010
URL: http://purl.umn.edu/102394

Ingredient classification according to the digestible amino acid profile: an exploratory analysis
Provedor de dados: 89
Autores: Faria Filho,DE; Torres,KAA; Campos,DMB; Vieira,BS; Urbano,T; Rosa,PS; Ferraudo,AS.
This study aimed: 1) to classify ingredients according to the digestible amino acid (AA) profile; 2) to determine ingredients with AA profile closer to the ideal for broiler chickens; and 3) to compare digestible AA profiles from simulated diets with the ideal protein profile. The digestible AA levels of 30 ingredients were compiled from the literature and presented as percentages of lysine according to the ideal protein concept. Cluster and principal component analyses (exploratory analyses) were used to compose and describe groups of ingredients according to AA profiles. Four ingredient groups were identified by cluster analysis, and the classification of the ingredients within each of these groups was obtained from a principal component analysis,...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Broiler chicken; Cluster analysis; Ideal protein; Ingredients; Principal component analysis.
Ano: 2005
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-635X2005000300009

Using numerical classification of profiles based on Vis-NIR spectra to distinguish soils from the Piracicaba Region, Brazil
Provedor de dados: 90
Autores: Rizzo,Rodnei; Demattê,José A. M.; Terra,Fabrício da Silva.
Considering that information from soil reflectance spectra is underutilized in soil classification, this paper aimed to evaluate the relationship of soil physical, chemical properties and their spectra, to identify spectral patterns for soil classes, evaluate the use of numerical classification of profiles combined with spectral data for soil classification. We studied 20 soil profiles from the municipality of Piracicaba, State of São Paulo, Brazil, which were morphologically described and classified up to the 3rd category level of the Brazilian Soil Classification System (SiBCS). Subsequently, soil samples were collected from pedogenetic horizons and subjected to soil particle size and chemical analyses. Their Vis-NIR spectra were measured, followed by...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Soil reflectance; Soil classification; Principal component analysis; OSACA algorithm.
Ano: 2014
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-06832014000200002

Magnetic susceptibility to identify landscape segments on a detailed scale in the region of Jaboticabal, São Paulo, Brazil
Provedor de dados: 90
Autores: Barrios,Mariana dos Reis; Marques Junior,José; Panosso,Alan Rodrigo; Siqueira,Diego Silva; La Scala Junior,Newton.
The agricultural potential is generally assessed and managed based on a one-dimensional vision of the soil profile, however, the increased appreciation of sustainable production has stimulated studies on faster and more accurate evaluation techniques and methods of the agricultural potential on detailed scales. The objective of this study was to investigate the possibility of using soil magnetic susceptibility for the identification of landscape segments on a detailed scale in the region of Jaboticabal, São Paulo State. The studied area has two slope curvatures: linear and concave, subdivided into three landscape segments: upper slope (US, concave), middle slope (MS, linear) and lower slope (LS, linear). In each of these segments, 20 points were randomly...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Landforms; Principal component analysis; Cluster analysis.
Ano: 2012
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-06832012000400002

Bacteria diversity and microbial biomass in forest, pasture and fallow soils in the southwestern Amazon basin
Provedor de dados: 90
Autores: Cenciani,Karina; Lambais,Marcio Rodrigues; Cerri,Carlos Clemente; Azevedo,Lucas Carvalho Basílio de; Feigl,Brigitte Josefine.
It is well-known that Amazon tropical forest soils contain high microbial biodiversity. However, anthropogenic actions of slash and burn, mainly for pasture establishment, induce profound changes in the well-balanced biogeochemical cycles. After a few years the grass yield usually declines, the pasture is abandoned and is transformed into a secondary vegetation called "capoeira" or fallow. The aim of this study was to examine how the clearing of Amazon rainforest for pasture affects: (1) the diversity of the Bacteria domain evaluated by Polymerase Chain Reaction and Denaturing Gradient Gel Electrophoresis (PCR-DGGE), (2) microbial biomass and some soil chemical properties (pH, moisture, P, K, Ca, Mg, Al, H + Al, and BS), and (3) the influence of...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Land use changes; PCR-DGGE; Bacterial diversity; Microbial biomass; Principal component analysis.
Ano: 2009
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-06832009000400015

Multivariate Analysis and Machine Learning in Properties of Ultisols (Argissolos) of Brazilian Amazon
Provedor de dados: 90
Autores: Souza,Cristiano Marcelo Pereira de; Thomazini,André; Schaefer,Carlos Ernesto Gonçalves Reynaud; Veloso,Gustavo Vieira; Moreira,Guilherme Musse; Fernandes Filho,Elpídio Inácio.
ABSTRACT: Ultisols are the most common soil order in the Brazilian Amazon. The Legal Amazon (LA) has an area of 5 × 106 km2, with few accessible areas, which restricts studies of soils at a detailed level. The pedological properties can be estimated more efficiently using statistical procedures and machine learning techniques, tools which are capable of recognizing patterns in a large soil database. We analyzed the main chemical and physical properties of the B horizons of the Ultisols of the Brazilian Amazon, as well as the spatial variability of the most explanatory properties of these horizons. Physical and chemical data of 1,068 profiles of the RadamBrasil Project were used. A principal component analysis (PCA) was applied and the most explanatory...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Legal Amazon; Principal component analysis; Morphostructural domains; Climatic zones.
Ano: 2018
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-06832018000100317

Soil spectral library and its use in soil classification
Provedor de dados: 90
Autores: Bellinaso,Henrique; Demattê,José Alexandre Melo; Romeiro,Suzana Araújo.
Soil science has sought to develop better techniques for the classification of soils, one of which is the use of remote sensing applications. The use of ground sensors to obtain soil spectral data has enabled the characterization of these data and the advancement of techniques for the quantification of soil attributes. In order to do this, the creation of a soil spectral library is necessary. A spectral library should be representative of the variability of the soils in a region. The objective of this study was to create a spectral library of distinct soils from several agricultural regions of Brazil. Spectral data were collected (using a Fieldspec sensor, 350-2,500 nm) for the horizons of 223 soil profiles from the regions of Matão, Paraguaçu Paulista,...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Remote sensing; Principal component analysis; Soil classification.
Ano: 2010
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-06832010000300027

Management Systems Effect on Fertility Indicators of a Ferralsol with Vegetable Crops, as Determined by Different Statistical Tools
Provedor de dados: 90
Autores: Lima,Carlos Eduardo Pacheco; Silva,Juscimar da; Guedes,Ítalo Moraes Rocha; Madeira,Nuno Rodrigo; Fontenelle,Mariana Rodrigues.
ABSTRACT The intensive nature of soil use in vegetable production areas has led to a marked decrease in soil quality. The objective of this study was to evaluate the effects of adoption of soil management systems on vegetable production with regards to the chemical properties of a Rhodic Ferralsol after five years and to evaluate the use of the Principal Component Analysis (PCA) statistical tool in discriminating the different treatments. The experiment was conducted under field conditions in central Brazil in a randomized block design with four replications and a 3 × 2 factorial arrangement (three soil management systems × two cover crops). The soil management systems used were NT (no-tillage), RT (reduced tillage), and CT (conventional tillage). The...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: No-tillage system; Reduced tillage system; Conventional tillage system; Principal component analysis.
Ano: 2017
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-06832017000100527

Geochemical Signature of Amazon Tropical Rainforest Soils
Provedor de dados: 90
Autores: Souza,José João Lelis Leal de; Fontes,Maurício Paulo Ferreira; Gilkes,Robert; Costa,Liovando Marciano da; Oliveira,Teogenes Senna de.
ABSTRACT: Evaluating soil geochemical diversity in the Amazon Basin has been a challenge largely because most study sites have been at the edge of the basin and it is difficult to get samples in such a region. Here we show that even among the most weathered soils, physicochemical soil properties express lithology. Our results are based on topsoil samples collected from different locations in minimally disturbed areas in the state of Amazonas, Brazil. Soil properties were measured using methods which are suitable for highly developed soils. The Chemical Index Alteration and Weathering Index of Parker was calculated based on the content of metal(loid)s in soils determined by X-ray fluorescence. Descriptive statistics, Pearson correlation, and Principal...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Heavy metals; Principal component analysis; XRF; Rainforest soils.
Ano: 2018
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-06832018000100403

Partitioning of rainfall into throughfall, stemflow, and interception loss in the Brazilian Northeastern Atlantic Forest
Provedor de dados: 91
Autores: Ribeiro Filho,Jacques C.; Lemos Filho,Luis C. de A.; Santos,Julio C. N. dos; Brasil,José B.; Palácio,Helba A. de Q.
ABSTRACT Information on hydrology, and vegetation distribution is essential for the development of techniques and strategies to cope with droughts in semi-arid environments. The objective of this study was to evaluate the partitioning of gross rainfall into throughfall, stemflow, and interception loss in the Brazilian Northeastern Atlantic Forest, and its correlations with rainfall characteristics. The study was conducted in the Bica watershed, in Portalegre, state of Rio Grande do Norte, Brazil. The work was carried out in 2017, with monitoring of the throughfall, stemflow, and interception loss in an area ​​of 10 × 20 m. Total rainfall depths (TRD) and wind speed were measured, and the evapotranspiration (ET0) was estimated. Based on this information,...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Caatinga; Hydrology; Semi-arid; Principal component analysis.
Ano: 2019
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-43662019000100021

Phenotypic diversity between Brazilian fighting cocks and naturalized roosters
Provedor de dados: 96
Autores: Ibiapina Neto,Vicente; Barbosa,Firmino José Vieira; Campelo,José Elivalto Guimarães; Sarmento,José Lindenberg Rocha; Santos,Natanael Pereira da Silva; Carvalho,Marcos David Figueiredo de.
ABSTRACT The present study was carried out to evaluate the phenotypic diversity between fighting cocks; roosters of the naturalized ecotypes Graúna Dourada, Brejeira, Teresina, and Nordestina; roosters of the Sertaneja genetic (synthetic) group; and family-farmed roosters via descriptive and multivariate analyses. The qualitative traits evaluated by descriptive analysis indicated a prevalence of single comb in the Graúna Dourada, Teresina, Nordestina, and Sertaneja ecotypes, whereas the Brejeira ecotype, fighting cocks, and family-farmed roosters have a pea-type comb, which can be viewed as a sign of introgression of the fighting cock in flocks of the region. Dark plumage prevailed across the groups. The quantitative traits subjected to multivariate...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Cluster analysis; Morphometry; Multivariate analysis; Principal component analysis.
Ano: 2019
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-35982019000100303

Influence of forage production area, concentrate supply, and workforce on productive results in milk production systems
Provedor de dados: 96
Autores: Koerich,Guilherme; Damasceno,Julio Cesar; Bánkuti,Ferenc Istvan; Parré,José Luiz; Santos,Geraldo Tadeu dos.
ABSTRACT This study aimed to investigate the influence of forage production area, concentrate supply, and farm labor on characterization of milk production systems (MPS) and their productive results. Milk volume data provided in 2014 by 110 dairy farms located in the eastern region of Santa Catarina State, Brazil, were obtained from a dairy industry. Forty-four farms with different production levels were selected, in which interviews were carried out aiming to characterize the management practices related to forage production area, concentrate supply, and farm labor. A principal component analysis (PCA) was performed. Then, regressions were made between the principal components (PC) and indicator variables of productive response (annual milk production,...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Cluster; Multivariate analysis; Principal component analysis.
Ano: 2019
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-35982019000100100

Bioactive phytochemicals and antioxidant activity in fresh and dried lychee fractions1
Provedor de dados: 124
Autores: Queiroz,Estela de Rezende; Abreu,Celeste Maria Patto de; Oliveira,Kelly da Silva; Ramos,Vinicius de Oliveira; Fráguas,Rodrigo Martins.
Fruit of the lychee cv. Bengal are approximately 50% peel and seeds, which are discarded. These by-products have antioxidant compounds which are capable of blocking the harmful effects of free radicals in the body. Bioactive compounds (ascorbic acid, beta-carotene, lycopene and phenols) and antioxidant activity were evaluated in different extracts, both fresh and dried at 45 °C, of the skin, pulp and seeds of the lychee, which were subjected to principal component analysis to clarify which of the compounds are responsible for this activity. Principal component analysis explained 82.90% of the variance of the antioxidant profile of the lychee. The peel displayed higher levels of phenols, ascorbic acid, beta-carotene and antioxidant activity, while the seeds...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Lychee; Antioxidants; Principal component analysis.
Ano: 2015
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1806-66902015000100163

Multivariate analysis and vigor tests to determine the quality of Brachiaria decumbens seeds
Provedor de dados: 124
Autores: Silva,Givanildo Zildo da; Martins,Cibele Chalita; Bruno,Riselane de Lucena Alcântara; Pereira,Francisco Elder Carlos Bezerra; Jeromini,Tatiane Sanches.
ABSTRACT This study aimed to verify the efficiency of multivariate analysis in the identification of promising vigor tests for the evaluation of the physiological quality of seed lots of Brachiaria decumbens cv. Basilisk. Seeds of B. decumbens cv. Basilisk were tested for the following parameters: water content, germination, first germination count, cold test, electrical conductivity, seedling growth, seedling dry mass, first count and emergence percentage of seedlings in laboratory substrate, and seedling emergence in the field. The data obtained in each test-all completely randomized experimental designs-were analyzed separately by means of analysis of variance, Scott-Knott’s test, and multivariate analysis. Principal component analysis is efficient to...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Physiological quality; Control quality; Principal component analysis; Grass forage; Seedling emergence in field.
Ano: 2019
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1806-66902019000200291

Soil management of sugarcane fields affecting CO2 fluxes
Provedor de dados: 63
Autores: Tavares,Rose Luiza Moraes; Siqueira,Diego Silva; Panosso,Alan Rodrigo; Castioni,Guilherme Adalberto Ferreira; Souza,Zigomar Menezes de; Scala Jr.,Newton La.
ABSTRACT The harvesting system of green sugarcane, characterized by mechanized harvesting and no crop burning, affects soil quality by increasing the remaining straw left on the soil surface after harvesting, thus, contributing to the improvement of physical, chemical, and microbiological soil attributes, influencing CO2 fluxes. This study aimed to evaluate CO2 fluxes and their relation to soil properties in sugarcane crops under different harvesting managements: burned (B), Green harvesting for 5 years (G-5) and Green harvesting for ten years (G-10). For this, a 1 ha sampling grid with 30 points was installed in each area, all located in the Northeast of São Paulo State, Brazil. In each point, CO2 fluxes were measured and the soil was sampled to analyze...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Sacharum officinarum; Principal component analysis; Porosity; Biomass.
Ano: 2016
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-90162016000600543

Mulch materials in processing tomato: a multivariate approach
Provedor de dados: 63
Autores: Moreno,Marta María; Moreno,Carmen; Tarquis,Ana María.
Mulch materials of different origins have been introduced into the agricultural sector in recent years alternatively to the standard polyethylene due to its environmental impact. This study aimed to evaluate the multivariate response of mulch materials over three consecutive years in a processing tomato (Solanum lycopersicon L.) crop in Central Spain. Two biodegradable plastic mulches (BD1, BD2), one oxo-biodegradable material (OB), two types of paper (PP1, PP2), and one barley straw cover (BS) were compared using two control treatments (standard black polyethylene [PE] and manual weed control [MW]). A total of 17 variables relating to yield, fruit quality, and weed control were investigated. Several multivariate statistical techniques were applied,...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Mulching; Principal component analysis; Cluster analysis; Discriminant analysis.
Ano: 2013
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-90162013000400005

Physical attributes of Cambisol in apple ( Malus domestica Borkh. cv. Gala) orchard under different weed management systems in Urubici- Santa Catarina, Brazil
Provedor de dados: 109
Autores: Schmitz,Daniela; Loss,Arcângelo; Oliveira,Bruno Salvador; Lovato,Paulo Emilio; Veiga,Milton da; Brunetto,Gustavo; Curmi,Pierre; Comin,Jucinei José.
Abstract The aim of this research was to evaluate the physical attributes of Cambisol in apple (Malus domestica Borkh. cv. Gala) orchard under different weed management systems in the state of Santa Catarina (SC), Brazil. The treatments were as follows: control (no weed management), chemical desiccation and mowing. We took samples of undisturbed soil at depths of 0-5, 5-10, 10-15 and 15-20 cm. We evaluated hydraulic conductivity (HC); bulk density (BD); soil penetration resistance (Pr); total porosity (TP), macropores (MaP), micropores (MiP); soil aggregation indices such as arithmetic and geometric mean diameter of air-dried and water-stable aggregates (AMDad, AMDws, GMDad, GMDws, respectively); aggregate stability index (ASIAMD and ASIGMD) and volumetric...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Bulk density; Chemical desiccation and mowing of weeds; Aggregate indices; Penetration resistance; Principal component analysis.
Ano: 2017
URL: http://www.scielo.org.co/scielo.php?script=sci_arttext&pid=S0120-28122017000300414

Comparative leaf anatomy and micromorphology of Psychotria species (Rubiaceae) from the Atlantic Rainforest
Provedor de dados: 39
Autores: Moraes,Tarsila Maria da Silva; Rabelo,Guilherme Rodrigues; Alexandrino,Camilla Ribeiro; Silva Neto,Sebastião José da; Da Cunha,Maura.
The genus Psychotria comprises approximately 2,000 species that are mostly shrubs distributed in forests of the tropics and subtropics. Within the Rubiaceae, Psychotria is well known for its species that produce bioactive alkaloids and for its taxonomic complexity. The anatomical and micromorphological characters of the leaves of P. hoffmannseggiana, P. carthagenensis, P. deflexa, P. glaziovii, P. leiocarpa, P. racemosa, and P. vellosiana were investigated and described to understand the interspecific variation of these species, which will contribute to the systematics of the genus. Principal component analysis (PCA) and unweighted pair group method analysis (UPGMA) indicated four groups based on the presence or absence of some of the characters studied....
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Leaf anatomy; Cluster analysis; Principal component analysis; Systematic anatomy; Domatia; Leaf surface morphology.
Ano: 2011
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0102-33062011000100021

Univariate and multivariate statistical tools for in vitro conservation of citrus genotypes
Provedor de dados: 1
Autores: Carvalho, Mariane de Jesus da Silva de; Souza, Antônio da Silva; Santos, Emanuela Barbosa; Soares Filho, Walter dos Santos; Ledo, Carlos Alberto da Silva; Souza, Fernanda Vidigal Duarte.
This study aimed to evaluate the influence of the growing environment on the in vitro conservation of citrus genotypes obtained from the Active Citrus Germplasm Bank of Embrapa Cassava and Fruit. The study used multivariate statistic tools in order to improve the efficiency in the analysis of the results. Approximately 1-cm of length microcuttings from plantlets derived from ten genotypes previously cultured in vitro were inoculated in test tubes containing 20 mL of WPM culture medium supplemented with 25 g L-1 sucrose, solidified with 7 g L-1 agar and adjusted to a pH of 5.8, and maintained under three environmental conditions for 180 days. The experiment was carried out in a completely randomized design in a split-plot in the space, with 15 replications....
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Agronomia; Ciências Agrárias multivariate analysis of variance; Partial correlation; Principal component analysis; Germplasm; Citrus spp. Conservação in vitro.
Ano: 2016
URL: http://periodicos.uem.br/ojs/index.php/ActaSciAgron/article/view/26433

Evaluation of an electronic nose system for characterization of pomegranate varieties
Provedor de dados: 111
Autores: Sanaeifar, Alireza; Mohtasebi, Seyed Saeid; Ghasemi-Varnamkhasti, Mahdi; Mohammad Shafie, Mohammad.
The electronic nose (e-nose) would simulate the human sense (smell) to identify and realize the complex aromas by employing a chemical sensors array. One of the most common sensors used in electronic nose systems are metal oxide semiconductor (MOS) sensors. In this research, a low cost e-nose system based on six metal oxide semi-conductor (MOS) sensors as a non-destructive instrument for recognition pomegranate varieties is investigated. Principal component analysis (PCA) and linear discriminant analysis (LDA) techniques are used for this purpose. The proposed e-nose has a capability of demonstrating a clear difference in aroma fingerprint of pomegranate by PCA and LDA analysis. Using LDA analysis, it is possible to identify and to categorize the...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Electronic nose; Linear discriminant analysis; Non-destructive; Pomegranate; Principal component analysis.
Ano: 2016
URL: http://www.cigrjournal.org/index.php/Ejounral/article/view/3799

Propolis from Southwest of Parana produced by selected bees: Influence of seasonality and food supplementation on antioxidant activity and phenolic profile
Provedor de dados: 42
Autores: CALEGARI,MATHEUS A.; PRASNIEWSKI,ANACLARA; SILVA,CLEIDIANE DA; SADO,RICARDO Y.; MAIA,FABIANA M.C.; TONIAL,LARISSA M.S.; OLDONI,TATIANE L.C.
ABSTRACT Propolis produced by selected bees Apis mellifera were collected from March to June of 2013 and in March of 2015 and analyzed in order to evaluate the influence of climate, colony of origin, and food supplementation of colonies on the content of total phenolic and flavonoid by chromatographic analysis and antioxidant activity by radical scavenging of 2,2-diphenyl-1-picrylhydrazyl hydrate (DPPH) and 2,2’-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) and ferric reducing antioxidant power (FRAP) methods. The Principal Component Analysis (PCA) was carried out with propolis collected in 2013 and two clusters were formed. Propolis produced in the months of March and April showed a higher content of total phenolic compounds (TPC) and...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Apis mellifera; Ethanolic extract; Polyphenols; Principal component analysis.
Ano: 2017
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0001-37652017000100045

Organography of greenhouse and field accessions of wild Arachisspecies (section Arachis)
Provedor de dados: 53
Autores: Veiga,Renato Ferraz de Arruda; Faria,Leonardo de Grazia; Valls,José Francisco Montenegro; Fávero,Alessandra Pereira.
ABSTRACT Peanut or groundnut (Arachis hypogaea L.) is a globally important oilseed crop, with important nutritional qualities, and a rich source of amino acids and protein. Another 80 species have been described in the genus Arachis, 64 of which are found in Brazil, and even though their morphology and agronomic traits remain largely unknown, they have been cultivated for forage and for landscaping and have great potential for breeding with cultivated peanut. Thus, the morphological characterization of wild Arachis species is essential for their conservation and use. In this study, we present a morphological and agronomic characterization of 29 diploid accessions of eleven wild Arachis species and one of the tetraploid A. monticola (section Arachis) with A...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Peanut; Morphological characterization; Descriptors; Principal component analysis.
Ano: 2018
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0006-87052018000100083

Cycle, physicochemical characterization and climatic adaptation of a white hybrid grape on different rootstocks
Provedor de dados: 53
Autores: Mattar,Gabriel Stefanini; Modesto,Lenon Romano; Hernandes,José Luiz; Tecchio,Marco Antonio; Moura,Mara Fernandes.
ABSTRACT This study evaluated the cycle duration, physicochemical characteristics of fruits and climatic adaptation of the ‘SR 501-17’ hybrid grape grafted on four rootstocks for the production of white wine. We tested four rootstocks, ‘IAC 766 Campinas’, ‘IAC 572 Jales’, ‘IAC 571-6 Jundiaí’ and ‘IAC 313 Tropical’, planted in two climatic regions, Cfa and Aw, in the state of São Paulo, Brazil in the cultivation years 2014 and 2015. Cycle duration, production, cluster weight, number of berries per bunch, content of soluble solids, titratable acidity, a maturation index and the weight, length and width of berries were evaluated. A principal component analysis characterized the cultivar for both climatic regions and years. The rootstock did not influence the...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Canopy/rootstock; Climate; Principal component analysis; Vitis.
Ano: 2019
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0006-87052019000300470

The vascular flora of the cerrado in Emas National Park (Central Brazil): a savanna flora summarized
Provedor de dados: 52
Autores: Batalha,Marco Antônio; Martins,Fernando Roberto.
The Brazilian cerrado may be divided in two main phytogeographic sectors: one characterized by Piptocarpha rotundifolia, in which the Emas National Park (ENP) is located, and other characterized by Curatella americana. We carried out a floristic survey in ENP, which allowed an assessment of the taxonomic composition, taxa size, and similarity with other sites for the ENP's vascular flora. We compared the ENP's flora with southeastern outlying cerrado sites, also in the Piptocarpha sector, and with general floristic patterns in the cerrado vegetation. The distribution of species per family in ENP was significantly different from that obtained for each component of the general cerrado flora. The herbaceous component was characterized by an overproportion of...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Cerrado; Floristics; Phytogeography; Principal component analysis; Savanna.
Ano: 2007
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-89132007000200012

Phenotypic Characterization and Genetic Diversity of Sugarcane Varieties Cultivated in Northern Karnataka of India based on Principal Component and Cluster Analyses
Provedor de dados: 52
Autores: Tawadare,Rakesh; Thangadurai,Devarajan; Khandagave,Rayappa Bharamappa; Mundaragi,Abhishek; Sangeetha,Jeyabalan.
Abstract: Sugarcane is a major commercial crop grown in India and across the world. Hence, several elite varieties have been developed now-a-days to overcome many obstacles including abiotic stresses and diseases. The present study was undertaken to screen genetic variation among twenty four sugarcane varieties that are commonly cultivated across Northern Karnataka, India with reference to physicochemical characters. Experiment was conducted in triplicate following randomized complete block design (RCBD) at S. Nijalingappa Sugar Institute, Belagavi, Karnataka, India during February 2016-17. Physiological parameters such as internode length, stalk height, plant height, stalk girth, number of internodes, single cane weight, single cane volume of juice, cane...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Physicochemical characters; Principal component analysis; Agglomerative hierarchical clustering; Sugarcane.
Ano: 2019
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-89132019000100215

Chemical quality of bottled mineral waters from markets of Curitiba-PR-Brazil
Provedor de dados: 52
Autores: Santos,Éder José dos; Oliveira Junior,Dasio Roberto de; Hermann,Amanda Beatriz; Sturgeon,Ralph Edward.
ABSTRACT Twenty-seven bottled mineral waters from local markets in Curitiba, State of Paraná, Brazil were analyzed for a number of constituents, including: pH, conductivity, total dissolved solids, hardness, HCO3  - and CO 3  2-, as well as Ca2+, Mg2+, Na+, K+, NH4 + , F-, Cl-, NO3 -, NO2 - and SO4 2- by ion chromatography (IC); Al, Ba, Cd, Cr, Cu, Fe, Li, Mn, Ni, Sr, V and Zn by inductively coupled plasma optical emission spectrometry (ICP OES); Hg by cold vapor generation-ICP OES and As, Pb, Sb and Se by ICP-mass spectrometry (ICP-MS). The obtained limits of quantitation (LOQ) were adequate for the determination of all analytes using the various analytical techniques. Results for the analysis of AccuStandard certified reference materials QCS-01-5,...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Bottled mineral waters; Elemental composition; Chemical quality; Principal component analysis.
Ano: 2016
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-89132016000100513

Long-term social recognition memory in adult male rats: factor analysis of the social and non-social behaviors
Provedor de dados: 56
Autores: Moura,P.J.; Meirelles,S.T.; Xavier,G.F.
A modified version of the intruder-resident paradigm was used to investigate if social recognition memory lasts at least 24 h. One hundred and forty-six adult male Wistar rats were used. Independent groups of rats were exposed to an intruder for 0.083, 0.5, 2, 24, or 168 h and tested 24 h after the first encounter with the familiar or a different conspecific. Factor analysis was employed to identify associations between behaviors and treatments. Resident rats exhibited a 24-h social recognition memory, as indicated by a 3- to 5-fold decrease in social behaviors in the second encounter with the same conspecific compared to those observed for a different conspecific, when the duration of the first encounter was 2 h or longer. It was possible to distinguish...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Agonistic behavior; Long-term social recognition memory; Non-social behavior; Principal component analysis; Social behavior; Social investigation.
Ano: 2010
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-879X2010000700009

Benchmarking pathway interaction network for colorectal cancer to identify dysregulated pathways
Provedor de dados: 56
Autores: Wang,Q.; Shi,C.-J.; Lv,S.-H.
Different pathways act synergistically to participate in many biological processes. Thus, the purpose of our study was to extract dysregulated pathways to investigate the pathogenesis of colorectal cancer (CRC) based on the functional dependency among pathways. Protein-protein interaction (PPI) information and pathway data were retrieved from STRING and Reactome databases, respectively. After genes were aligned to the pathways, each pathway activity was calculated using the principal component analysis (PCA) method, and the seed pathway was discovered. Subsequently, we constructed the pathway interaction network (PIN), where each node represented a biological pathway based on gene expression profile, PPI data, as well as pathways. Dysregulated pathways...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Pathway interaction network; Colorectal cancer; Dysregulated pathways; Principal component analysis; Protein-protein interaction.
Ano: 2017
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-879X2017000500602

Combining Multivariate Analysis and Pollen Count to Classify Honey Samples Accordingly to Different Botanical Origins
Provedor de dados: 117
Autores: Corbella,Eduardo; Cozzolino,Daniel.
This study reports the combination of multivariate techniques and pollen count analysis to classify honey samples accordingly to botanical sources, in samples from Uruguay. Honey samples from different botanical origins, namely Eucalyptus spp. (n = 10), Lotus spp. (n = 12), Salix spp. (n = 5), “mil flores” (Myrtaceae spp.) (n = 12) and coronilla (Scutia buxifolia Reissek) (n = 10) were analysed using Melissopalynology (pollen identification). Principal component analysis (PCA) and linear discriminant analysis (LDA) were used to classify the honey samples accordingly to their botanical origin based on a pollen count. Honey samples of higher percentage (&gt; 70%) of Eucalyptus, Lotus and Scutia pollen were 100% correctly classified, whilst samples from...
Tipo: Journal article
Palavras-chave: Honey; Uruguay; Principal component analysis; Linear discriminant analysis; Pollen analysis.
Ano: 2008
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392008000100010

The identification of outstanding potato cultivars using multivariate methods
Provedor de dados: 118
Autores: Pérez,Delfina de J; González,Andrés; Sahagún,Jaime; Vázquez,Luis M; Rivera,Antonio; Franco,Omar; Domínguez,Aurelio.
The evaluation and selection of potato (Solanum tuberosum) cultivars for commercial production in the high valleys of Mexico are important for plant breeding, seed production, and the generation of technology. In this work, ten potato cultivars from five different environments in México were evaluated to determine the proportion of genetic variation contained within each. The potatoes were sown in a completely randomized complete block design. Heritability was determined to be between 53% and 83%, suggesting that there is genetic variability among the potato cultivars that might be agronomically important. According to the additive main effects and multiplicative interaction (AMMI) model, the highest tuber yields were obtained at the locality named...
Tipo: Journal article
Palavras-chave: AMMI model; Cluster analysis; Principal component analysis; Solanum tuberosum.
Ano: 2009
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-16202009000300006

Usefulness of near infrared reflectance (NIR) spectroscopy and chemometrics to discriminate between fishmeal, meat meal and soya meal samples
Provedor de dados: 118
Autores: Cozzolino,Daniel; Restaino,Ernesto; La Manna,Alejandro; Fernandez,Enrique; Fassio,Alberto.
Near infrared reflectance (NIR) spectroscopy was used in combination with chemometrics to discriminate between fishmeal, meat meal and soya meal samples. Samples were obtained from commercial feed miles and scanned in the NIR region (1100 - 2500 nm) in a monochromatic instrument in reflectance mode. Principal component analysis (PCA) and linear discriminant analysis were used to classify samples based on their NIR spectra. Full cross-validation was used in the development of classification models. Partial least squares-discriminant analysis (PLS-DA) correctly classified 85.7% of the fishmeal samples and 100% of the meat meal and soya meal samples. These results demonstrate the usefulness of NIR spectra combined with chemometrics as an objective and rapid...
Tipo: Journal article
Palavras-chave: Fishmeal; Glycine max; Meat meal; Near infrared; Principal component analysis; Spectroscopy; Soya meal.
Ano: 2009
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-16202009000200005

Snap bean production using sunflowers as living trellises in the central high valleys of Mexico
Provedor de dados: 118
Autores: Morales-Rosales,Edgar Jesús; Franco-Mora,Omar; González-Huerta,Andrés.
The aim of this study was to assess growth, net assimilation rate, biomass production and pod yield in two snap bean cultivars sown in monoculture and combined with two sunflower cultivars at three localities in the State of Mexico, Mexico. The six treatments were evaluated in a 2 x 3 factorial experiment in a randomized complete block design with four replications. When F values were significant, the least significant difference test at the 5% level of significance was used. The principal component analysis was also used to study the interrelationship among the six treatments and seven variables. The results observed in the biplot indicated that the largest original variation in the data was adequately represented in the first two principal components...
Tipo: Journal article
Palavras-chave: Phaseoulus vulgaris; Helianthus annuus; Multiple crops; Net assimilation rate; Principal component analysis.
Ano: 2011
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-16202011000100005

Nutritional and bioactive compounds of adzuki beans cultivars using chemometric approach
Provedor de dados: 64
Autores: Gohara,Aline Kirie; Souza,Aloisio Henrique Pereira de; Gomes,Sandra Terezinha Marques; Souza,Nilson Evelázio de; Visentainer,Jesuí Vergílio; Matsushita,Makoto.
ABSTRACT Azuki beans are small red grains rich in several essential nutrients used in traditional dishes in Asia that, nowadays present many applications around the world. This work aimed at evaluating angularis and niponensis cultivars from south region of Brazil. Both cultivars presented proximal composition similar to literature and the majority fatty acids were 18:2n-6, 16:0 and 18:3n-3. All samples showed polyunsatured fatty acids prevalence and nutritional indices and ratios considered adequate for biological system maintenance of a healthy organism. The grains presented significant contents of tocopherols and vitamin E activity, resulting in a high contribution to the dietary reference intake. Significant contents of iron, manganese and zinc were...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Vigna angularis; Alpha-linolenic; Principal component analysis; Vitamin E; Antioxidant activity.
Ano: 2016
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1413-70542016000100104

Development, characterization and chemometric analysis of a gluten-free food bar containing whole flour from a new cultivar of amaranth
Provedor de dados: 64
Autores: Pagamunici,Lilian Maria; Souza,Aloisio Henrique Pereira; Gohara,Aline Kirie; Souza,Nilson Evelázio; Gomes,Sandra Terezinha Marques; Matsushita,Makoto.
Food bars are consumed heavily, especially because of their practicality; however they cannot be ingested by celiac patients and present low contents of essential nutrients. The goal of this study was the development and physical-chemical, nutritional and sensory evaluation of a gluten-free food bar containing amaranth and linseed. Gluten fractions were not detected in the food bar formulations. Crude protein and total lipid contents ranged from 68.32 to 76.60 and 74.56 to 82.06 g kg-1 of food, respectively. The polyunsaturated/saturated and n-6:n-3 fatty acid ratios ranged from 0.45:1 to 0.55:1 and 1.44:1 to 2.50:1, respectively. Calcium, magnesium, copper, iron, manganese and zinc were the principal minerals. Application of multivariate analysis enabled...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Principal component analysis; Pseudo-cereals; Linseed; Fatty acids.
Ano: 2014
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1413-70542014000300007