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Biology ◽  
2021 ◽  
Vol 10 (7) ◽  
pp. 595
Author(s):  
Vinicio Barquero ◽  
Eduardo R. S. Roldan ◽  
Carles Soler ◽  
Bernardo Vargas-Leitón ◽  
Francisco Sevilla ◽  
...  

The aim was to determine the relationship between kinematic parameters of boar spermatozoa and fertility rates of sow, as well as to assess the effect of sperm clusters on the fertility capacity of the ejaculate. Semen samples were collected from 11 sexually mature boars. Samples were analyzed by an ISAS®v1 CASA-Mot system for eight kinematic parameters. Ejaculate clusters were characterized using multivariate procedures, such as principal factors (PFs) analysis and clustering methods (the k-means model). Four different ejaculate clusters were identified from two kinematic PFs which involved linear trajectory and velocity. There were differences (p < 0.05) between the sperm kinematic variables by sire line. There was no statistical difference (p > 0.05) between dam lines and ejaculate clusters in fertility variables. The discriminant ability of the different kinematics of sperm variables to predict litter size fertility was analyzed using receiver operating characteristics (ROC) curve analysis. Curvilinear velocity (VCL), average path velocity (VAP), amplitude of lateral head displacement (ALH), and beat-cross frequency (BCF) showed significant, albeit limited, predictive capacity for litter size fertility variables (range: 0.55–0.58 area under curve, AUC). The kinematic analysis of the ejaculates in clusters did not have a predictive capacity for litter size variables.


2020 ◽  
Vol 55 (3) ◽  
pp. 163-183
Author(s):  
Romeo Di Pietro ◽  
Antonio Luca Conte ◽  
Piera Di Marzio ◽  
Lorenzo Gianguzzi ◽  
Giovanni Spampinato ◽  
...  

AbstractSpecies identification within the species complex of Q. pubescens is a well-known taxonomic challenge among European botanists. Some of the specific pubescent oak binomials currently accepted in various European floras and checklists were originally described in Sicily and southern Calabria. As a consequence, several species belonging to the pubescent oaks group (Q. pubescens, Q. amplifolia, Q. congesta, Q. dalechampii, Q. leptobalana and Q. virgiliana) are reported in the taxonomic and phytosociological literature. To verify whether it was possible to associate a diverse set of morphological characters with each of these different taxa, thirteen natural populations of pubescent oak from Sicily and southern Calabria were sampled. A total of 391 trees, 3,887 leaves and 1,047 fruits were collected. Overall, 28 morphological characters of oak leaves and fruits were statistically analysed using univariate and multivariate procedures. The results showed that neither the groups of morphological diversity identified by cluster analysis, nor those obtained by our expert identification through the use of analytical keys, matched with the current taxonomical frameworks as proposed by the most recent floras and checklists. Nearly all of the morphological characters considered displayed a more or less continuous trend of variation, both within and among populations. In the light of these findings it seems unlikely that more than one biological species of pubescent oak occurs in Sicily and southern Calabria.


Biology ◽  
2020 ◽  
Vol 9 (6) ◽  
pp. 138
Author(s):  
Luis Víquez ◽  
Vinicio Barquero ◽  
Carles Soler ◽  
Eduardo R.S. Roldan ◽  
Anthony Valverde

The ejaculate is heterogenous and sperm sub-populations with different kinematic patterns can be identified in various species. Nevertheless, although these sub-populations are statistically well defined, the statistical differences are not always relevant. The aim of the present study was to characterize kinematic sub-populations in sperm from two bovine species, and diluted with different commercial extenders, and to determine the statistical relevance of sub-populations through Bayesian analysis. Semen from 10 bulls was evaluated after thawing. An ISAS®v1 computer-assisted sperm analysis (CASA)-Mot system was employed with an image acquisition rate of 50 Hz and ISAS®D4C20 counting chambers. Sub-populations of motile spermatozoa were characterized using multivariate procedures such as principal components (PCs) analysis and clustering methods (k-means model). Four different sperm sub-populations were identified from three PCs that involved progressiveness, velocity, and cell undulatory movement. The proportions of the different sperm sub-populations varied with the extender used and in the two species. Despite a statistical difference (p < 0.05) between extenders, the Bayesian analysis confirmed that only one of them (Triladyl®) presented relevant differences in kinematic patterns when compared with Tris-EY and OptiXcell®. Extenders differed in the proportion of sperm cells in each of the kinematic sub-populations. Similar patterns were identified in Bos taurus and Bos indicus. Bayesian results indicate that sub-populations SP1, SP2, and SP3 were different for PC criteria and these differences were relevant. For velocity, linearity, and progressiveness, the SP4 did not show a relevant difference regarding the other sperm sub-populations. The classical approach of clustering or sperm subpopulation thus may not have a direct biological meaning. Therefore, the biological relevance of sperm sub-populations needs to be reevaluated.


2019 ◽  
Vol 37 (3) ◽  
pp. 315-323
Author(s):  
Naysa Flávia F do Nascimento ◽  
Elizanilda R do Rêgo ◽  
Mayana F Nascimento ◽  
Cláudio H Bruckner ◽  
Fernando L Finger ◽  
...  

ABSTRACT The cultivation of potted peppers as ornamental plants has increased considerably throughout the planet. In Brazil, this crop is more recent and still lacks cultivars. In order to increase the available variability and obtain new cultivars, the interspecific hybridization is very useful in add a desirable attribute that occurs in one species to another species, resulting in a new cultivar of agronomic interest. The objective of this study was to characterize parents and interspecific hybrids based on 27 quantitative traits and evaluate their genetic diversity by multivariate procedures. Parents of seven pepper genotypes were crossed, and, seven hybrids were generated. The experiment was conducted in a completely randomized design. Data were subjected to analysis of variance, and means were subsequently grouped by Scott-Knott’s method. Tocher’s method was utilized based on Mahalanobis distance, and the relative importance was evaluated by Singh’s method. The effects of treatment were significant by F test at 1 and 5% probability for all studied traits, except for anther length and titratable acidity. According to Scott-Knott’s test, the genotypes were grouped into two to eight classes. By Tocher’s method, the genotypes were separated into four groups. The first three canonical variables explained 92.02% of the total variance. By Singh method, fruit yield per plant was the trait that most contributed to the divergence explaining 21% of the total variance. The studied parents and hybrids diverged for the evaluated traits; however, there was difficulty in obtaining good interspecific hybrids with traits of importance, wherein combinations HS1×L7, L2×L6, and HS1×L2 met these requirements.


2019 ◽  
Vol 13 (2) ◽  
pp. 277-292 ◽  
Author(s):  
Jeferson Carvalho Alvarenga ◽  
Robson Rosa Branco ◽  
André Luis Azevedo Guedes ◽  
Carlos Alberto Pereira Soares ◽  
Wainer da Silveira e Silva

Purpose The past few decades have produced a number of investigations into the correlation between project managers’ competencies and project success. As a result, competencies lists have become extensive “shopping lists.” The purpose of this paper is to define the most important competencies to project success and investigate their correlations. Design/methodology/approach The authors surveyed project managers on the importance of 28 project manager competencies to project success. Data were analyzed using univariate and multivariate procedures. Findings Data show that communication, commitment and leadership appear as the three most relevant aspects. Multivariate analysis identified seven groups of competencies: leadership, self-management, interpersonal, communication, technical, productivity and managerial. Practical implications The results confirm a growing trend toward soft skills and reinforce the need for an update on project management education to fill the gap between theory and practice. Originality/value Project manager competencies lists have become too extensive, and the field is in constant change; therefore, this study updates the discussion and downsizes the number of competencies to fewer, more relevant items.


2019 ◽  
Vol 3 (1) ◽  
Author(s):  
Mary W Carter ◽  
Bo Kyum Yang ◽  
Marsha Davenport ◽  
Allison Kabel

Abstract Objective This study sought to investigate factors associated with opioid misuse-related emergency department (ED) visits among older adults and changes in outcomes associated with these visits, using multiple years of nationally representative data. Methods A retrospective analysis of the Nationwide Emergency Department Sample was conducted. Study inclusion was limited to adults aged 65 years and older. Diagnostic codes were used to identify opioid misuse disorder; sampling weights were used to adjust standard estimates of the errors. Descriptive and multivariate procedures were used to describe risk and visit outcomes. Results ED visits by older adults with opioid misuse identified in the ED increased sharply from 2006 to 2014, representing a nearly 220% increase over the study period. Opioid misuse was associated with an increased number of chronic conditions, greater injury risk, and higher rates of alcohol dependence and mental health diagnoses. Conclusion The steep increase in opioid misuse observed among older adult ED visits underscores the critical need for additional research to better understand the national scope and impact of opioid misuse on older adults, as well as to better inform policy responses to meet the needs of this particular age group.


2018 ◽  
pp. 24-33
Author(s):  
Ana da Silva Lédo ◽  
Tatiana Nascimento Silva ◽  
Carlos Roberto Martins ◽  
Ana Veruska Cruz da Silva ◽  
Carlos Alberto da Silva Lédo ◽  
...  

Weed Science ◽  
2017 ◽  
Vol 66 (1) ◽  
pp. 78-93 ◽  
Author(s):  
Richard G. Smith ◽  
Sonja K. Birthisel ◽  
Sidney C. Bosworth ◽  
Bryan Brown ◽  
Thomas M. Davis ◽  
...  

The northern New England region includes the states of Vermont, New Hampshire, and Maine and encompasses a large degree of climate and edaphic variation across a relatively small spatial area, making it ideal for studying climate change impacts on agricultural weed communities. We sampled weed seedbanks and measured soil physical and chemical characteristics on 77 organic farms across the region and analyzed the relationships between weed community parameters and select geographic, climatic, and edaphic variables using multivariate procedures. Temperature-related variables (latitude, longitude, mean maximum and minimum temperature) were the strongest and most consistent correlates with weed seedbank composition. Edaphic variables were, for the most part, relatively weaker and inconsistent correlates with weed seedbanks. Our analyses also indicate that a number of agriculturally important weed species are associated with specific U.S. Department of Agriculture plant hardiness zones, implying that future changes in climate factors that result in geographic shifts in these zones will likely be accompanied by changes in the composition of weed communities and therefore new management challenges for farmers.


AGROFOR ◽  
2016 ◽  
Vol 1 (1) ◽  
Author(s):  
Naser Sabaghnia

In breeding for plant disease resistance programs, a large number of new improvedgenotypes are tested over a range of test pathogens or environments and theunderlying statistics used to model this system may be rather complicated. Due toordinal nature of most measured traits of disease responses, some nonparametricmethods used for analyzing genotype × environment (GE) interaction in twodatasets for disease severity of gray leaf spot of maize (with ten genotypes plantedin 10 and 11 environments). Usually, the presence of the GE interaction effectcomplicates the selection of the most favorable genotypes and there are severalstatistical procedures available to analyze these dataset including a range ofunivariate, nonparametric and multivariate procedures. Present analysis separatednonparametric methods based on dynamic concept from those which are based onthe static type indicated that RS statistic following to S6, NP2, NP3 and RSstatistics were found to be useful in detecting the non-complicated phenotypicstability in disease severity dataset. In complicated GE interaction, the ability ofAMMI stability parameters especially SPC1, SPCF, D1, DF, EV1, EVF and ASVstatistics were high in the detection of stability in complicated GE interaction. Ingeneral, nonparametric methods are useful alternatives to parametric methods andallow drawing valid conclusions with considerably better chances of detecting theGE interaction in experiments of plant pathology. Also, in some cases the GEinteraction structure is too complex to be summarized by only one parameter andso, it is essential to use multivariate statistical methods like AMMI.


2016 ◽  
Vol 34 (3) ◽  
pp. 374-380 ◽  
Author(s):  
Jacqueline C Araujo ◽  
Samuel FP Telhado ◽  
Rogério H Sakai ◽  
Carlos AS Ledo ◽  
Paulo CT Melo

ABSTRACT Tomato is one of the most important crops, the worldwide production in 2012 reached 161.8 million tons. Considering the lack of agronomic information on already available cultivars as well as on the varieties under development by breeding programs for organic systems, the objectives of this work were determine the yield components of 14 tomato cultivars in the organic system, through univariate and multivariate analysis. The experimental design was randomized blocks with six replications and five plants per plot. Evaluations consisted of total, marketable and non-marketable yield and number of marketable fruits per plant, in 2010. We carried out analysis of variance, using test F 5%. The effect of cultivar was fixed and the block effect was random. Then, means were ranked according to Scott-Knott 5%. Differences among cultivars were significant for total yield, number of marketable fruits per plant and marketable yield. The mean for total yield among cultivars was 51 t/ha and for marketable yield was 41 t/ha. Cultivars IAC 1 and Santa Clara were the least dissimilar (0.38). On the other hand, cultivars HTV 0601 and IAC 3 were the most dissimilar (10.63). The score dispersion graph showed two distinct groups. The second group contained cultivars HTV 0601, Granadero, Bari and Netuno, which stood out in the evaluation for the organic production system, presenting the highest total yield, marketable yield and number of marketable fruits per plant. Multivariate analysis was effective in identifying clusters of cultivars.


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