scholarly journals Verifiability of genus-level classification under quantification and parsimony theories: a case study of follicucullid radiolarians

Paleobiology ◽  
2020 ◽  
Vol 46 (3) ◽  
pp. 337-355
Author(s):  
Yifan Xiao ◽  
Noritoshi Suzuki ◽  
Weihong He ◽  
Michael J. Benton ◽  
Tinglu Yang ◽  
...  
Keyword(s):  
Morphological Evolution ◽  
Late Paleozoic ◽  
Ancestral State ◽  
Multivariate Statistical ◽  
Quantification Theory ◽  
State Reconstruction ◽  
Multivariate Statistical Method ◽  
Multivariate Method

AbstractThe classical taxonomy of fossil invertebrates is based on subjective judgments of morphology, which can cause confusion, because there are no codified standards for the classification of genera. Here, we explore the validity of the genus taxonomy of 75 species and morphospecies of the Follicucullidae, a late Paleozoic family of radiolarians, using a new method, Hayashi's quantification theory II (HQT-II), a general multivariate statistical method for categorical datasets relevant to discriminant analysis. We identify a scheme of 10 genera rather than the currently accepted 3 genera (Follicucullus, Ishigaconus, and Parafollicucullus). As HQT-II cannot incorporate stratigraphic data, a phylogenetic tree of Follicucullidae was reconstructed for 38 species using maximum parsimony. Six lineages emerged, roughly in concordance with the results of HQT-II. Combined with parsimony ancestral state reconstruction, the ancestral group of this family is Haplodiacanthus. Five other groups were discriminated, the Parafollicucullus, Curvalbaillella, Pseudoalbaillella, Longtanella, and Follicucullus–Cariver lineages. The morphological evolution of these lineages comprises a minimum essential list of eight states of four traits. HQT-II is a novel discriminant analytical multivariate method that may be of value in other taxonomic problems of paleobiology.

Phylogenetics, ancestral state reconstruction, and a new infrageneric classification of Scleria (Cyperaceae) based on three DNA markers

Taxon ◽  
2016 ◽  
Vol 65 (3) ◽  
pp. 444-466 ◽  
Author(s):  
Kenneth Bauters ◽  
Pieter Asselman ◽  
David A. Simpson ◽  
A. Muthama Muasya ◽  
Paul Goetghebeur ◽  
...  
Keyword(s):  
Dna Markers ◽  
Ancestral State Reconstruction ◽  
Ancestral State ◽  
Infrageneric Classification ◽  
State Reconstruction

scholarly journals Peripheral areas and their distinctive characteristics: The case of Hungary

2021 ◽  
Vol 29 (3) ◽  
pp. 217-230
Author(s):  
János Pénzes ◽  
Gábor Demeter
Keyword(s):  
Cluster Analysis ◽  
Hierarchical Cluster Analysis ◽  
Hierarchical Cluster ◽  
Multivariate Statistical Methods ◽  
Multivariate Statistical ◽  
Development Policies ◽  
Relevant Variables ◽  
Peripheral Areas

Abstract The delimitation and classification of peripheral settlements using multivariate statistical methods is presented in this article, with a case study of Hungary. A combination of four different methods provided the basis for the delimitation of settlements defined as peripheral. As significant overlapping was detected between the results of the different methods, peripheries – more than one-fifth of the Hungarian settlements – were identified in a common set of the results. The independence of the results from the applied methods points to the fact that peripherisation is multi-faceted, and the peripheries of Hungary are stable and well-discernible from other regions. After the identification of peripheral areas, we classified these settlements into groups based on their specific features. Multiple steps specifying the relevant variables resulted in selecting the most appropriate 10 indicators and these served as the basis for a hierarchical cluster analysis, through which 7 clusters (types of peripheries) were identified. Five of them comprised enough cases to detect the most important dimensions and specific features of the backwardness of these groups. These clusters demonstrated a spatial pattern and their socioeconomic and infrastructural features highlighted considerable disparities. These differences should be taken into consideration when development policies are applied at regional levels or below.

Dioxin, dioxin-like PCBS and organotin compounds in the river Elbe and the Hamburg harbour: identification of sources

1998 ◽  
Vol 37 (6-7) ◽  
pp. 207-215 ◽  
Author(s):  
Rainer Götz ◽  
Bernd Steiner ◽  
Susanne Sievers ◽  
Peter Friesel ◽  
Klaus Roch ◽  
...  
Keyword(s):  
Surface Waters ◽  
Hierarchical Cluster ◽  
Chemical Production ◽  
Multivariate Statistical ◽  
Multivariate Statistical Method ◽  
Flood Plains ◽  
River Elbe ◽  
Thermal Origin ◽  
Dioxin Contamination

Using neural networks (in this case the Kohonen network) and a multivariate statistical method - the hierarchical cluster analysis -, a classification of dioxin data has been carried out. A principal conclusion, which can be drawn, is that a significant source of dioxin in the river Elbe, Hamburg harbour, the soils of the flood plains of the river Elbe and in soils originating from dredging materials, has been shown to originate from the dioxin contaminated region of Bitterfeld. The results indicate that the dioxin contamination in the Bitterfeld region was caused partly by metallurgy processes, not just by chemical production. Furthermore, the results show that a main dioxin source responsible for the contamination of Hamburg surface waters, not influenced by the river Elbe, is of “thermal origin”. The river Elbe shows a characteristic butyltin pattern. The cause is probably a plant in Bitterfeld. The precise sources of the dioxin-like PCB are still unknown.

The evolution of the dicynodont sacrum: constraint and innovation in the synapsid axial column

Paleobiology ◽  
2019 ◽  
Vol 45 (1) ◽  
pp. 201-220 ◽  
Author(s):  
Christopher T. Griffin ◽  
Kenneth D. Angielczyk
Keyword(s):  
Body Size ◽  
Poisson Regression ◽  
Vertebral Column ◽  
Morphological Evolution ◽  
Ancestral State ◽  
Caudal Vertebra ◽  
State Reconstruction ◽  
Universal Feature ◽  
Body Sizes ◽  
Close Relatives

AbstractConstraint is a universal feature of morphological evolution. The vertebral column of synapsids (mammals and their close relatives) is a classic example of this phenotypic restriction, with greatly reduced variation in the number of vertebrae compared with the sauropsid lineage. Synapsids generally possess only three sacral vertebrae, which articulate with the ilium and play a key role in locomotion. Dicynodont anomodonts are the exception to this rule, possessing seven or more sacral vertebrae while reaching a range of body sizes rivaled among synapsids only by therian mammals. Here we explore the evolution of this unusual sacral morphology in dicynodonts by (1) hypothesizing homologies of the additional sacral vertebrae, (2) using ancestral state reconstruction and phylogenetic regressions (e.g., logistic regression, Poisson regression) to track the coevolution of sacral count and body size, and (3) proposing mechanisms by which additional sacral vertebrae were incorporated during dicynodont evolution. We find that sacral vertebral morphology covaries with sacral count in consistent ways across dicynodonts, implying that sacra with a given number of vertebrae are composed of homologous elements. There is a correlation between increased sacral count and larger body size, especially at the shift from four to five sacrals near the origin of Bidentalia. Based on position, morphology, and the consistent number of presacral vertebrae among dicynodonts, we hypothesize that the additional sacrals anterior to the plesiomorphic three are duplications of the first sacral, and that a single caudosacral was incorporated by a shift in the identity of the anteriormost caudal vertebra. Although changes in sacral count appear to be correlated with shifts in body size in dicynodonts, the evolution of general morphological conservativism in the synapsid sacrum remains to be further explored.

LATE PALEOZOIC REGIONAL PALEOCLIMATE OF THE PROTOPRECORDILLERAN GONDWANA MARGIN: A CASE STUDY IN THE PAGANZO BASIN

2018 ◽  
Author(s):  
Kathryn N. Pauls ◽  
◽  
John L. Isbell ◽  
Levi D. Moxness ◽  
C. Oscar Limarino ◽  
...  
Keyword(s):  
Late Paleozoic ◽  
Gondwana Margin ◽  
Paganzo Basin

scholarly journals Assessment of health/functioning of older adults who consume psychoactive substances

2018 ◽  
Vol 71 (3) ◽  
pp. 942-950
Author(s):  
Vania Dias Cruz ◽  
Silvana Sidney Costa Santos ◽  
Jamila Geri Tomaschewski-Barlem ◽  
Bárbara Tarouco da Silva ◽  
Celmira Lange ◽  
...  
Keyword(s):  
Older Adults ◽  
Qualitative Case Study ◽  
International Classification Of Functioning ◽  
Psychoactive Substances ◽  
Systematic Observation ◽  
Health Functioning ◽  
Final Consideration ◽  
Theory Of Complexity

ABSTRACT Objective: To assess the health/functioning of the older adult who consumes psychoactive substances through the International Classification of Functioning, Disability and Health, considering the theory of complexity. Method: Qualitative case study, with 11 older adults, held between December 2015 and February 2016 in the state of Rio Grande do Sul, using interviews, documents and non-systematic observation. It was approved by the ethics committee. The analysis followed the propositions of the case study, using the complexity of Morin as theoretical basis. Results: We identified older adults who consider themselves healthy and show alterations - the alterations can be exacerbated by the use of psychoactive substances - of health/functioning expected according to the natural course of aging such as: systemic arterial hypertension; depressive symptoms; dizziness; tinnitus; harmed sleep/rest; and inadequate food and water consumption. Final consideration: The assessment of health/functioning of older adults who use psychoactive substances, guided by complex thinking, exceeds the accuracy limits to risk the understanding of the phenomena in its complexity.

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