scholarly journals The locomotor and predatory habits of unenlagiines (Theropoda, Paraves): inferences based on morphometric studies and comparisons with Laurasian dromaeosaurids

2019 ◽  
Author(s):  
Federico A. Gianechini ◽  
Marcos D. Ercoli ◽  
Ignacio Díaz-Martínez
Keyword(s):  
Principal Component ◽  
Mechanical Efficiency ◽  
The Other ◽  
Large Prey ◽  
Data Sampling ◽  
Morphological Aspects ◽  
Articular Surfaces ◽  
Morphometric Analyses ◽  
Principal Component Analyses ◽  
Evolutionary Paths

AbstractUnenlagiinae is mostly recognized as a subclade of dromaeosaurids. They have the modified pedal digit II that characterize all dromeosaurids, which is typically related to predation. However, derived Laurasian dromaeosaurids (eudromaeosaurs) differ from unenlagiines in having a shorter metatarsus and pedal phalanx II-1, and more ginglymoid articular surfaces in metatarsals and pedal phalanges. Further, unenlagiines have a subarctometatarsal condition, which could have increased the mechanical efficiency during locomotion. All these discrepancies possibly reflect different locomotor and predatory habits. To evaluate this we conducted morphometric analyses and comparisons of qualitative morphological aspects. The former consisted in two phylogenetic principal component analyses, one of them based on lengths of femur, tibia and metatarsus, and width of metatarsus, and the other based on lengths of pedal phalanges. The data sampling covered several coelurosaurian and non-coelurosaurian taxa. The first analysis showed the unenlagiines close to taxa with long tibiae and long and slender metatarsi, which are features considered to provide high cursorial capacities. Instead, eudromaeosaurs are close to taxa with shorter tibiae and shorter and wider metatarsi, which can be considered with low cursorial capacities. The second analysis showed that eudromaeosaurs and unenlagiines have similar phalangeal proportions. Moreover, they share the elongation of distal phalanges, which is a feature related to the capacity of grasping. The shorter and wider metatarsus, more ginglymoid articular surfaces and a shorter pedal phalanx II-2 of eudromaeosaurs possibly allowed them to exert a greater gripping strength. Thus, they had the potential of hunting large prey. Instead, the longer and slender subarctometatarsus, lesser ginglymoid articular surfaces and a longer pedal phalanx II-2 of unenlagiines possibly gave to them greater cursorial capacities and the ability to hunt smaller and elusive prey on the ground. Thus, the different morphological evolutionary paths of dromaeosaurids lineages seem to indicate different locomotor and predatory specializations.

Differences in efficiency between trained and recreational cyclists

2007 ◽  
Vol 32 (6) ◽  
pp. 1036-1042 ◽  
Author(s):  
James G. Hopker ◽  
Damian A. Coleman ◽  
Jonathan D. Wiles
Keyword(s):  
Oxygen Uptake ◽  
Maximal Oxygen Uptake ◽  
Mechanical Efficiency ◽  
Cycle Ergometer ◽  
The Other ◽  
Data Sampling ◽  
Training Experience ◽  
Cycling Efficiency ◽  
Gross Mechanical Efficiency

Controversy still exists in the literature as to whether cycling experience affects gross mechanical efficiency (GME). The aim of this study was to identify differences in efficiency between trained and untrained cyclists. Thirty-two participants, 16 trained (mean ± SD: age, 33 ± 4 y; height, 1.76 ± 0.05 m; mass 75 ± 10 kg; Wmax, 421 ± 38 W; maximal oxygen uptake, 62.6 ± 7.30 mL·kg–1·min–1) and 16 untrained (22 ± 3 y, 175 ± 0.06 m, 76 ± 10 kg, 292 ± 34 W, 42.6 ± 7.80 mL·kg–1·min–1), performed two tests of cycling efficiency. One was at the relative workloads of 50% and 60% Wmax and the other was at a fixed workload of 150 W using an electrically braked cycle ergometer. Cadence was maintained at the cyclist’s preferred rate throughout. All workloads lasted 10 min with data sampling in the final 3 min. GME was calculated from the gas data. GME was found to be significantly higher in the trained cyclists across all workloads (+1.4%; p = 0.03). At workloads of 60% Wmax GME was significantly lower than work at 150 W (–0.8%; p = 0.04), but not significantly different from 50%Wmax. These results show that differences do exist between trained and untrained cyclists, illustrating that training experience is a factor that warrants further investigation.

Distribution of the dwarf dog-faced bat Molossops temminckii (Chiroptera: Molossidae) in Colombia and comments on its morphometry

Mammalia ◽  
2020 ◽  
Vol 0 (0) ◽  
Author(s):  
Julio J. Chacón-Pacheco ◽  
Luis José Avendaño Maldonado ◽  
Carlos Agamez-López ◽  
Ingrith Yuliany Mejía-Fontecha ◽  
Daniela Velásquez-Guarín ◽  
...  
Keyword(s):  
South America ◽  
Morphological Variation ◽  
Principal Component ◽  
The Other ◽  
Cryptic Diversity ◽  
Vocal Plasticity ◽  
Morphometric Variation ◽  
Integrative Analyses ◽  
Principal Component Analyses

AbstractThe genus Molossops includes two species that are restricted to South America: Molossops neglectus and Molossops temminckii. The smaller dog-faced dwarf Molossops temminckii is distributed from Colombia to Argentina and has a wide morphological variation and vocal plasticity. In Colombia, this species remains poorly known. To fill distributional gaps, we present novel records from Arauca, Atlántico, Bolívar, Córdoba, and Huila departments. We also present an analysis of the morphometric variation in South America using Principal Component Analyses. These show an external and cranial difference of specimens of Colombia in respect of other and South America populations. In Colombian landscapes dominated by the floodplain savanna of the Orinoco region, Molossops temminckii is smaller than in the other regions of the country, and the previously suggested existence of cryptic diversity within the taxon should be evaluated. Therefore, we suggest further integrative analyses to investigate a possible subspecific status of some Colombian populations.

A psycholexical Study of Virtues in the Dutch Language, and Relations between Virtues and Personality

2011 ◽  
Vol 25 (1) ◽  
pp. 43-52 ◽  
Author(s):  
Boele De Raad ◽  
Jan Pieter Van Oudenhoven
Keyword(s):  
Big Five ◽  
Principal Component ◽  
The Other ◽  
Personality Measures ◽  
Regression Analyses ◽  
Self And Other ◽  
Five Factors ◽  
Principal Component Analyses ◽  
Dutch Language ◽  
Big Five Factors

Following the psycholexical approach, a list of 153 virtue descriptors was selected from a previously constructed list of trait–terms, under the assumption that virtues form a subset of traits. The virtue list was administered to 400 participants (self– and other–raters), who had to indicate the extent to which each term applied to them or to the others. Principal Component Analyses were performed yielding six factors of virtues. In addition, Big Five factors and markers of an external set of virtues were constructed. Correlation and regression analyses were performed to describe the relations between virtues, the Dutch Big Five system and other virtue systems. Compared to the other virtue systems, the present study revealed some additional domains. The overlap found with personality measures corresponds to earlier findings supporting the assumption that virtues are important traits. Copyright © 2010 John Wiley & Sons, Ltd.

scholarly journals The Essential Oil Compositions of Three Teucrium Taxa Growing Wild in Sicily: HCA and PCA Analyses

Molecules ◽  
2021 ◽  
Vol 26 (3) ◽  
pp. 643
Author(s):  
Giorgia Catinella ◽  
Natale Badalamenti ◽  
Vincenzo Ilardi ◽  
Sergio Rosselli ◽  
Laura De Martino ◽  
...  
Keyword(s):  
Cluster Analysis ◽  
Chemical Composition ◽  
Essential Oils ◽  
Principal Component ◽  
Hierarchical Cluster ◽  
The Other ◽  
Qualitative And Quantitative ◽  
Geographical Variations ◽  
Sesquiterpene Hydrocarbons ◽  
Principal Component Analyses

The chemical composition and the qualitative and quantitative variability of the essential oils of three taxa belonging to the Teucrium genus were studied. The investigated taxa, that grow wild in Sicily, were Teucrium flavum L. (section Chamaedrys (Mill.) Scheb.), Teucrium montanum and Teucrium capitatum L. of section Polium (Mill.) Scheb. Essential oils were extracted by hydrodistillation and analyzed by GC-MS. In total, 74 compounds were identified. Sesquiterpene hydrocarbons were found to be the main group for T. flavum (48.3%). T. capitatum consisted essentially of monoterpene hydrocarbons (72.7%), with α-pinene (19.9%), β-pinene (27.6%) and sylvestrene (16.6%) as the most abundant compounds whereas ledene oxide (12.1%), epiglobulol (13.5%) and longifolenaldehyde (14.5%) were identified as the main constituents among the oxygenated sesquiterpenes (63.5%) of T. montanum. Furthermore, a complete literature review on the composition of the essential oils of all the other accessions of these Teucrium taxa, studied so far, was performed. Hierarchical Cluster Analysis (HCA) and Principal Component Analyses (PCA) were used in order to demonstrate geographical variations in the composition of the essential oils.

THE CONVERGENCE OF HABITAT STRUCTURE IN TUNDRA COLLEMBOLAN COMMUNITIES (INSECTA: ORDER COLLEMBOLA)

1983 ◽  
Vol 115 (9) ◽  
pp. 1129-1145 ◽  
Author(s):  
Masanori J. Toda ◽  
Kouzou Tanno
Keyword(s):  
Habitat Structure ◽  
Principal Component ◽  
The Other ◽  
Statistical Techniques ◽  
Mackenzie Delta ◽  
Multivariate Statistical Techniques ◽  
Multivariate Statistical ◽  
Cluster Analyses ◽  
Ecological Changes ◽  
Principal Component Analyses

AbstractHabitat structure of two collembolan communities, one at Barrow, Alaska, U.S.A., the other at Tuktoyaktuk in the Mackenzie Delta, Canada, has been analyzed in relation to microtopographies characteristic of tundra regions. Multivariate statistical techniques, cluster analyses (UPGMA), and principal component analyses (PCA) reveal various ecological changes in component species. In spite of such local variations in component species, the two communities show similar patterns of habitat structure that are organized principally along a gradient of environmental moisture.

Multivariate analysis of the hybrid Phoxinus eos × Phoxinus neogaeus (Pisces: Cyprinidae): reevaluation of univariate analysis

1989 ◽  
Vol 67 (7) ◽  
pp. 1637-1641
Author(s):  
Gerard R. Joswiak ◽  
John G. New
Keyword(s):  
Univariate Analysis ◽  
Principal Component ◽  
The Other ◽  
Morphological Data ◽  
Multivariate Methods ◽  
Morphometric Measurements ◽  
Data Set ◽  
Principal Component Analyses ◽  
Two Factors ◽  
The Mean

Morphological data from two species of minnows, Phoxinus eos and Phoxinus neogaeus, and their hybrids (Pisces: Cyprinidae), previously analyzed by univariate methods, were reanalyzed by multivariate methods. Stepwise discriminant and principal component analyses were conducted on a data set of 14 morphometric measurements from 172 specimens. All of the Phoxinus neogaeus and 87% of both hybrids and Phoxinus eos were correctly classified on functions derived from six discriminating variables. Principal component analysis resulted in the extraction of two factors that explained 90% of the variation in the data set. Mean scores on the first factor were significantly different for P. eos, while on the second factor the mean score for P. neogaeus differed from those of the other two groups. Possible causes of variation in the morphology in the Phoxinus hybrids, from diploidy, tripoloidy, and mosaicism, are discussed.

Depression: A Multivariate Study of Sir Aubrey Lewis's Data on Melancholia

1977 ◽  
Vol 11 (3) ◽  
pp. 149-156 ◽  
Author(s):  
Leslie G. Kiloh ◽  
Roger F. Garside
Keyword(s):  
Principal Component ◽  
Endogenous Depression ◽  
The Other ◽  
Multivariate Study ◽  
Principal Component Analyses ◽  
Component Scores

Principal component analyses were carried out on 51 items abstracted from Lewis's 1934 and 1936 papers. The first component was bipolar, differentiating between endogenous items and those that were mainly neurotic. The distributions of the first component scores by cluster indicated that there were two separate clusters of patients, one mainly endogenous, the other neurotic. It was concluded that Lewis's data indicate that there are at least two qualitatively different depressive illnesses. Further component analyses were carried out using the 25 endogenous items. The first component was a general one of endogenous depression. The distributions of its scores were bimodal, indicating that there were two groups of patients, those who suffered from endogenous depression and those who did not. These analyses indicated that endogenous depression is a categorical illness.

The Twin Relationship Questionnaire

2020 ◽  
Vol 36 (2) ◽  
pp. 348-360 ◽  
Author(s):  
Hila Segal ◽  
Ariel Knafo-Noam
Keyword(s):  
Reliability And Validity ◽  
Principal Component ◽  
The Other ◽  
Prosocial Behaviors ◽  
Factor Analyses ◽  
Confirmatory Factor Analyses ◽  
Mothers And Fathers ◽  
Five Factors ◽  
Confirmatory Factor ◽  
Principal Component Analyses

Abstract. Twins’ relationships evoke critical dilemmas for parents and teachers regarding raising and educating their twins. The current study provides comprehensive psychometric information about the Twin Relationship Questionnaire (TRQ; Fortuna, Goldner, & Knafo, 2010 ) as examined in nine samples, using mothers’ and fathers’ reports on 1,560 pairs of twins, tested in five measurement points from age 3 to age 9. On half of the subsamples, we conducted principal component analyses (PCA), whereas on the other subsamples, we conducted confirmatory factor analyses (CFA). Five factors were found in the PCA and confirmed by the CFA: conflict, closeness, dependence, dominance, and rivalry. All scales showed adequate internal consistencies and corrected item-total correlations. Correlation matrixes between scales demonstrate a triad of conflict, rivalry, and dominance scales, as opposed to the dyad of closeness and dependence. As evidence for the TRQ’s reliability and validity, we report the degree of agreement between mothers and fathers, the 10-month stability of mothers’ reports, and the associations of the TRQ subscales with experimentally assessed prosocial behaviors between the twins at age 6.5, and with the twins’ reports on their closeness at age 11. The replication of the findings across ages and raters reinforces the reliability and validity of the questionnaire.

Dependence of the joint configuration on the dynamic immobility fulcrum

2019 ◽  
pp. 108-114
Author(s):  
A. D. Kozlov ◽  
Yu. P. Potekhina
Keyword(s):  
Kinetic Energy ◽  
Convex Surface ◽  
The Other ◽  
Concave Surface ◽  
Joint Configuration ◽  
Articular Surfaces

Although joints with synovial cavities and articular surfaces are very variable, they all have one common peculiarity. In most cases, one of the articular surfaces is concave, whereas the other one is convex. During the formation of a joint, the epiphysis, which has less kinetic energy during the movements in the joint, forms a convex surface, whereas large kinetic energy forms the epiphysis with a concave surface. Basing on this concept, the analysis of the structure of the joints, allows to determine forces involved into their formation, and to identify the general patterns of the formation of the skeleton.

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