How Selective Breeding Has Changed the Morphology of the American Mink (Neovison vison)—A Comparative Analysis of Farm and Feral Animals

In this study, we performed a comparative analysis of the morphological traits between feral (n = 43) and farm (n = 200) individuals of the American mink in Poland to address the question of how multigenerational intensive selective breeding has morphologically differentiated these two populations. Nine body measurements and two proportion coefficients were obtained using adult individuals. The significance of differences between population means was assessed using the Wilcoxon test for independent samples, while the Kruskal–Wallis test was used to compare sex-population groups. Spearman’s correlation coefficients between measurements were estimated for each population. We also performed Principal Component Analysis (PCA) to identify the variables that were most closely correlated with variation in the trait measurements and to investigate the morphological differences between farm and feral minks. We found that the farm minks exhibited significantly higher mean values for eight out of eleven studied traits. Moreover, significant changes in forelimb length, with no concomitant changes in hindlimb length, were accompanied by differences in body shape: trapezoidal in feral minks and rectangular in farm minks. The PCA suggested an almost complete separation of the two populations and indicated that sexes were quite separate; farm males in particular constitute a wholly discrete cluster. Such a clear differentiation between the two populations and sexes over a period of several decades highlights the intensity of selective breeding in shaping the morphology of these animals.

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

Brazilian Journal of Oceanography ◽

10.1590/s1679-87592012000300003 ◽

2012 ◽

Vol 60 (3) ◽

pp. 299-310 ◽

Cited By ~ 8

Author(s):

Luciane Ayres-Peres ◽

Aline Ferreira Quadros ◽

Fernando L. Mantelatto

Keyword(s):

Principal Component Analysis ◽

Comparative Analysis ◽

Hermit Crab ◽

Regression Tree ◽

Principal Component ◽

Hermit Crabs ◽

Pca Analysis ◽

Internal Volume ◽

The Relationship ◽

Two Populations

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

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Population differences in morphological and anatomical traits of Pinus mugo Turra needles from the Polish part of the Tatra Mountains

Forest Research Papers ◽

10.1515/frp-2017-0007 ◽

2017 ◽

Vol 78 (1) ◽

pp. 67-76

Author(s):

Ewa M. Pawlaczyk ◽

Alina Bączkiewicz ◽

Piotr Wawrzyniak ◽

Magdalena Czołpińska ◽

Patrycja Gonera ◽

...

Keyword(s):

Natural Variation ◽

Pearson Correlation ◽

Correlation Coefficients ◽

Principal Component ◽

Pinus Mugo ◽

Tatra Mountains ◽

Tatra Mts ◽

The Tatra Mountains ◽

The Relationship ◽

Two Populations

Abstract The main aim of this study was to describe the variation between the populations of the dwarf mountain pine Pinus mugo Turra based on the morphological and anatomical traits of their needles, and to investigate the relationship between the observed variation and environmental conditions (altitude and substrate). Two-year-old needles were collected from 180 individuals of six populations of P. mugo growing in the Tatra Mts. Two populations were classified as dense, located at 1360–1450 m altitude, and the remaining four formed loose clusters and were situated at 1500–1650 m altitude. Four of the populations are growing on granite and two on a limestone substrate. The natural variation of 10 morpho-anatomical and 3 synthetic needle traits was measured. In addition to descriptive statistics, the analyses of variance (ANOVA) with a Tukey test and principal component analysis were computed. We also estimated Pearson correlation coefficients for the examined needle traits and altitude as well as substrate. Our results indicate that the P. mugo populations differ significantly with regard to the investigated traits for which the Trzydniowiański Wierch population was the most distinct. The observed pattern of variability is largely caused by differences in stomatal traits and these features are positive correlated with altitude. Additionally, populations growing on granite have larger values for most of the examined traits compared to populations growing on limestone.

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Comparison of Principal Component Solutions in Two Populations

Methodology ◽

10.1027/1614-2241/a000099 ◽

2016 ◽

Vol 12 (1) ◽

pp. 11-20 ◽

Cited By ~ 1

Author(s):

Gregor Sočan

Keyword(s):

Simulation Study ◽

Principal Components ◽

Common Factor ◽

Principal Component ◽

Component Model ◽

Bootstrap Procedure ◽

Factor Loadings ◽

Component Loadings ◽

Principal Component Model ◽

Two Populations

Abstract. When principal component solutions are compared across two groups, a question arises whether the extracted components have the same interpretation in both populations. The problem can be approached by testing null hypotheses stating that the congruence coefficients between pairs of vectors of component loadings are equal to 1. Chan, Leung, Chan, Ho, and Yung (1999) proposed a bootstrap procedure for testing the hypothesis of perfect congruence between vectors of common factor loadings. We demonstrate that the procedure by Chan et al. is both theoretically and empirically inadequate for the application on principal components. We propose a modification of their procedure, which constructs the resampling space according to the characteristics of the principal component model. The results of a simulation study show satisfactory empirical properties of the modified procedure.

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Contrast-Enhanced MRI with Magnetization Transfer Effect in the Imaging of Brain Metastatic Lesions

Medical Visualization ◽

10.24835/1607-0763-2017-5-8-17 ◽

2017 ◽

pp. 8-17

Author(s):

A. A. Ermakova ◽

O. Yu. Borodin ◽

M. Yu. Sannikov ◽

S. D. Koval ◽

V. Yu. Usov

Keyword(s):

Comparative Analysis ◽

Roc Analysis ◽

Magnetization Transfer ◽

Metastatic Lesion ◽

Transfer Effect ◽

Wilcoxon Test ◽

Post Contrast ◽

Metastatic Lesions ◽

The Brain ◽

Non Parametric

Purpose: to investigate the diagnostic opportunities of contrast magnetic resonance imaging with the effect of magnetization transfer effect in the diagnosis of focal metastatic lesions in the brain.Materials and methods.Images of contrast MRI of the brain of 16 patients (mean age 49 ± 18.5 years) were analysed. Diagnosis of the direction is focal brain lesion. All MRI studies were carried out using the Toshiba Titan Octave with magnetic field of 1.5 T. The contrast agent is “Magnevist” at concentration of 0.2 ml/kg was used. After contrasting process two T1-weighted studies were performed: without T1-SE magnetization transfer with parameters of pulse: TR = 540 ms, TE = 12 ms, DFOV = 24 sm, MX = 320 × 224 and with magnetization transfer – T1-SE-MTC with parameters of pulse: ΔF = −210 Hz, FA(МТС) = 600°, TR = 700 ms, TE = 10 ms, DFOV = 23.9 sm, MX = 320 x 224. For each detected metastatic lesion, a contrast-to-brain ratio (CBR) was calculated. Comparative analysis of CBR values was carried out using a non-parametric Wilcoxon test at a significance level p < 0.05. To evaluate the sensitivity and specificity of the techniques in the detection of metastatic foci (T1-SE and T1-SE-MTC), ROC analysis was used. The sample is divided into groups: 1 group is foci ≤5 mm in size, 2 group is foci from 6 to 10 mm, and 3 group is foci >10 mm. Results.Comparative analysis of CBR using non-parametric Wilcoxon test showed that the values of the CBR on T1-weighted images with magnetization transfer are significantly higher (p <0.001) that on T1-weighted images without magnetization transfer. According to the results of the ROC analysis, sensitivity in detecting metastases (n = 90) in the brain on T1-SE-MTC and T1-SE was 91.7% and 81.6%, specificity was 100% and 97.6%, respectively. The accuracy of the T1-SE-MTC is 10% higher in comparison with the technique without magnetization transfer. Significant differences (p < 0.01) between the size of the foci detected in post-contrast T1- weighted images with magnetization transfer and in post-contrast T1-weighted images without magnetization transfer, in particular for foci ≤5 mm in size, were found. Conclusions1. Comparative analysis of CBR showed significant (p < 0.001) increase of contrast between metastatic lesion and white matter on T1-SE-MTC in comparison with T1-SE.2. The sensitivity, specificity and accuracy of the magnetization transfer program (T1-SE-MTC) in detecting foci of metastatic lesions in the brain is significantly higher (p < 0.01), relative to T1-SE.3. The T1-SE-MTC program allows detecting more foci in comparison with T1-SE, in particular foci of ≤5 mm (96% and 86%, respectively, with p < 0.05).

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Chemometric Analysis for the Classification of some Groups of Drugs with Divergent Pharmacological Activity on the Basis of some Chromatographic and Molecular Modeling Parameters

Combinatorial Chemistry & High Throughput Screening ◽

10.2174/1386207321666180129102149 ◽

2018 ◽

Vol 21 (2) ◽

pp. 125-137

Author(s):

Jolanta Stasiak ◽

Marcin Koba ◽

Marcin Gackowski ◽

Tomasz Baczek

Keyword(s):

Correlation Analysis ◽

Pharmacological Activity ◽

Correlation Coefficients ◽

Principal Component ◽

Cardiovascular Drugs ◽

New Drugs ◽

Analgesic Drugs ◽

Starting Point ◽

Chromatographic Parameters

Aim and Objective: In this study, chemometric methods as correlation analysis, cluster analysis (CA), principal component analysis (PCA), and factor analysis (FA) have been used to reduce the number of chromatographic parameters (logk/logkw) and various (e.g., 0D, 1D, 2D, 3D) structural descriptors for three different groups of drugs, such as 12 analgesic drugs, 11 cardiovascular drugs and 36 “other” compounds and especially to choose the most important data of them. Material and Methods: All chemometric analyses have been carried out, graphically presented and also discussed for each group of drugs. At first, compounds’ structural and chromatographic parameters were correlated. The best results of correlation analysis were as follows: correlation coefficients like R = 0.93, R = 0.88, R = 0.91 for cardiac medications, analgesic drugs, and 36 “other” compounds, respectively. Next, part of molecular and HPLC experimental data from each group of drugs were submitted to FA/PCA and CA techniques. Results: Almost all results obtained by FA or PCA, and total data variance, from all analyzed parameters (experimental and calculated) were explained by first two/three factors: 84.28%, 76.38 %, 69.71% for cardiovascular drugs, for analgesic drugs and for 36 “other” compounds, respectively. Compounds clustering by CA method had similar characteristic as those obtained by FA/PCA. In our paper, statistical classification of mentioned drugs performed has been widely characterized and discussed in case of their molecular structure and pharmacological activity. Conclusion: Proposed QSAR strategy of reduced number of parameters could be useful starting point for further statistical analysis as well as support for designing new drugs and predicting their possible activity.

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Seed Set Patterns in East African Highland Cooking Bananas Are Dependent on Weather before, during and after Pollination

Horticulturae ◽

10.3390/horticulturae7070165 ◽

2021 ◽

Vol 7 (7) ◽

pp. 165

Author(s):

Allan Waniale ◽

Rony Swennen ◽

Settumba B. Mukasa ◽

Arthur K. Tugume ◽

Jerome Kubiriba ◽

...

Keyword(s):

Critical Period ◽

Floral Development ◽

Seed Set ◽

Correlation Coefficients ◽

Principal Component ◽

Maximum Temperature ◽

Fruit Pulp ◽

East African ◽

Average Temperature ◽

Wild Banana

Seed set in banana is influenced by weather, yet the key weather attributes and the critical period of influence are unknown. We therefore investigated the influence of weather during floral development for a better perspective of seed set increase. Three East African highland cooking bananas (EAHBs) were pollinated with pollen fertile wild banana ‘Calcutta 4′. At full maturity, bunches were harvested, ripened, and seeds extracted from fruit pulp. Pearson’s correlation analysis was then conducted between seed set per 100 fruits per bunch and weather attributes at 15-day intervals from 105 days before pollination (DBP) to 120 days after pollination (DAP). Seed set was positively correlated with average temperature (P < 0.05–P < 0.001, r = 0.196–0.487) and negatively correlated with relative humidity (RH) (P < 0.05–P < 0.001, r = −0.158–−0.438) between 75 DBP and the time of pollination. After pollination, average temperature was negatively correlated with seed set in ‘Mshale’ and ‘Nshonowa’ from 45 to 120 DAP (P < 0.05–P < 0.001, r = −0.213–−0.340). Correlation coefficients were highest at 15 DBP for ‘Mshale’ and ‘Nshonowa’, whereas for ‘Enzirabahima’, the highest were at the time of pollination. Maximum temperature as revealed by principal component analysis at the time of pollination should be the main focus for seed set increase.

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Sensitivity of bioelectrical impedance to detect changes in human body composition

Journal of Applied Physiology ◽

10.1152/jappl.1989.67.4.1643 ◽

1989 ◽

Vol 67 (4) ◽

pp. 1643-1648 ◽

Cited By ~ 36

Author(s):

R. Ross ◽

L. Leger ◽

P. Martin ◽

R. Roy

Keyword(s):

Body Composition ◽

Human Body ◽

Correlation Coefficients ◽

Bioelectrical Impedance ◽

Mean Values ◽

Significance Level ◽

Exercise Regimen ◽

Before And After ◽

Hydrostatic Weighing ◽

Human Body Composition

The purpose of this study was to compare the estimates of lean body mass (LBM) and percent body fat (%BF), as predicted by bioelectrical impedance (BIA) and sum of skinfolds (SF), with those derived by hydrostatic weighing (HW) obtained before and after a 10-wk diet and exercise regimen. The experimental (E) group consisted of 17 healthy male subjects; 20 healthy males served as the control (C) group. Post hoc Scheffe contrasts computed on E group data indicated that, for both LBM and %BF, the Lukaski and Segal BIA equations, as well as the Durnin SF equation, derived mean values that were not significantly different (0.05 significance level) from HW in both pre- and postregimen conditions. For LBM, the same equations derived the following significant (P less than 0.01) correlation coefficients for both pre- and postregimen data: Lukaski, 0.87 and 0.85; Segal, 0.89 and 0.87; and Durnin, 0.90 and 0.88. For %BF, the correlation coefficients were slightly lower but remained statistically significant (P less than 0.01). The findings of this study suggest that the BIA method, by use of either the Lukaski or Segal prediction equations, is a valid means of predicting changes in human body composition as measured by the Siri transformation of body density.

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Inhibition of Kynurenine Metabolism and Its Effect in Mitochondrial Function in Hepatocellular Carcinoma

Innovation in Aging ◽

10.1093/geroni/igaa057.410 ◽

2020 ◽

Vol 4 (Supplement_1) ◽

pp. 124-125

Author(s):

Raul Castro-Portuguez ◽

Samuel Freitas ◽

George Sutphin

Keyword(s):

Hepatocellular Carcinoma ◽

Mitochondrial Function ◽

De Novo ◽

Principal Component ◽

Kynurenine Pathway ◽

The Cancer Genome Atlas ◽

Wilcoxon Test ◽

Nad Synthesis ◽

Significant Difference ◽

Kynurenine Metabolism

Abstract Hepatocellular carcinoma (HCC) is the most prevalent cancer in the liver. The majority of ingested tryptophan is processed in the liver through the kynurenine pathway, the endpoint of which is de novo NAD+ biosynthesis. Dysregulation of tryptophan-kynurenine metabolism and NAD+ synthesis may promote mitochondrial malfunction, tumor reprogramming, and carcinogenesis. Using a publicly available gene expression dataset from liver hepatocellular carcinoma (LIHC) samples available through The Cancer Genome Atlas (TCGA; n = 371), we employed Principal Component Analysis (PCA), hierarchical clustering, gene-pattern expression profiling, and survival analysis to cluster patients and determine overall survival. Our analysis of genes encoding kynurenine pathway enzymes determined that patients with high QPRT expression had a poor prognosis with decreased median survival, with no effect on the maximum survival. There is a significant difference in the survival between patients with high QPRT expression relative to patients with high HAAO/AFMID expression (HR = 1.2, [95% CI 0.5-1.8] P = 0.0181, Gehan-Breslow-Wilcoxon Test). Patients with high QPRT expression have higher survival rates compared with low QPRT expression (HR = 1.4, [95% CI 0.9-2.2] P = 0.0344, Gehan-Breslow-Wilcoxon Test). To test the consequences of kynurenine-pathway inhibition in mitochondrial function and morphology we use 4-Cl-3HAA, an irreversible HAAO inhibitor, and observed a small increase in mitochondrial fragmentation in HepG2 cells after 24 hours of treatment. We conclude that kynurenine metabolism may be useful as a biomarker to predict patient prognosis among HCC patients. In ongoing work, we are testing QPRT inhibitors in cell culture as a potential adjuvant for chemotherapies.

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Correlating Variations in the Dynamic Resistance Signature to Weld Strength in Resistance Spot Welding Using Principal Component Analysis

Journal of Manufacturing Science and Engineering ◽

10.1115/1.4034887 ◽

2016 ◽

Vol 139 (4) ◽

Cited By ~ 4

Author(s):

David W. Adams ◽

Cameron D. E. Summerville ◽

Brendan M. Voss ◽

Jack Jeswiet ◽

Matthew C. Doolan

Keyword(s):

Principal Component Analysis ◽

Quality Control ◽

Spot Welding ◽

Correlation Coefficients ◽

Principal Component ◽

Weld Strength ◽

Dynamic Resistance ◽

Resistance Spot ◽

Resistance Spot Welds ◽

Key Features

Traditional quality control of resistance spot welds by analysis of the dynamic resistance signature (DRS) relies on manual feature selection to reduce the dimensionality prior to analysis. Manually selected features of the DRS may contain information that is not directly correlated to strength, reducing the accuracy of any classification performed. In this paper, correlations between the DRS and weld strength are automatically detected by calculating correlation coefficients between weld strength and principal components of the DRS. The key features of the DRS that correlate to weld strength are identified in a systematic manner. Systematically identifying relevant features of the DRS is useful as the correlations between weld strength and DRS may vary with process parameters.

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RELATIONSHIPS BETWEEN SOME PROPERTIES OF ORGANIC SOILS FROM THE SOUTHERN CANADIAN SHIELD

Canadian Journal of Soil Science ◽

10.4141/cjss90-037 ◽

1990 ◽

Vol 70 (3) ◽

pp. 363-377 ◽

Cited By ~ 5

Author(s):

D. ANN BROWN ◽

S. P. MATHUR ◽

ANTON BROWN ◽

D. J. KUSHNER

Keyword(s):

Principal Component Analysis ◽

Acid Leaching ◽

Principal Component ◽

Organic Soil ◽

Component Analysis ◽

Soil Types ◽

Organic Soils ◽

Mining Districts ◽

Two Populations ◽

Inorganic Components

Different numerical methods used to distinguish between organic soil types are evaluated. The research was initiated by the suggestion that acid leaching from mining wastes could be prevented by capping the tailings with a self-renewing methane-producing muskeg bog, in order to prevent the penetration of oxygen to the wastes. Thirty organic soils from bogs in the mining districts of Elliot Lake, Sudbury, and Timmins, Ontario, and Noranda, Quebec, were sampled and 28 soil characteristics were measured. These characteristics, whose values are normally or lognormally distributed, were analyzed by several different statistical methods. Some characteristics indicate the existence of two populations, and others are bivariantly correlated. Canonical discriminant analysis was more successful than cluster analysis in separating the bogs into well-defined geographical groups. However, principal component analysis proved best at grouping the organic soils according to their organic and inorganic components, and we suggest that this is a suitable method for the general discrimination of organic soil types. Methane was present in all the 17 bogs tested for it, and in two very wet bogs more than 2 mmol of methane per liter were extracted. Key words: Muskeg bog, organic soils, soil characterization, principal component analysis

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