Relationships within the genus Myoxocephalus (Pisces: Cottidae) based on morphological and biochemical data using numerical and conventional methods of analyses

1972 ◽  
Vol 50 (5) ◽  
pp. 671-682 ◽  
Author(s):  
Garry I. McT. Cowan
Keyword(s):  
Analytical Techniques ◽  
Morphological Data ◽  
Biochemical Data ◽  
Numerical Treatment ◽  
Malic Dehydrogenase ◽  
Systematic Relationships ◽  
Conventional Methods ◽  
Numerical Clustering

Systematic relationships within the cottid genus Myoxocephalus are derived, based on morphological and biochemical (muscle myogen, lactic and malic dehydrogenase electropherograms) characteristics. The effects of numerical and conventional taxonomic analyses on the relationships derived from both sources of data are investigated.Comparison of numerical clustering of morphological and biochemical data indicates that the relationships are not comparable. However if the data are combined, the relationships obtained are similar to those based solely on morphological information.Conventional analyses of 45 morphological and 35 biochemical characters yielded similar patterns of relationship. The biochemical ones are, however, notably more conservative and simplified. The two treatments of morphological data and the numerical treatment of combined morphological and biochemical data indicate very similar relationships. However the numerical treatment of biochemical data resulted in completely different affinities.It is nevertheless possible to conclude that where evidence is available from a wide variety of systems within the organism, the two analytical techniques yield similar results. Also the inclusion of a limited amount of biochemical data should not be expected to result in greatly improved or altered systematic conclusions.

Residual bootstraps for the uncertainty analysis of tidal models with temporally correlated noise 

2021 ◽  
Author(s):  
Silvia Innocenti ◽  
Pascal Matte ◽  
Vincent Fortin ◽  
Natacha Bernier
Keyword(s):  
Harmonic Analysis ◽  
River Flow ◽  
Analytical Techniques ◽  
Parametric Bootstrap ◽  
Correlated Noise ◽  
Series Length ◽  
Regression Residuals ◽  
Conventional Methods ◽  
Improved Performance ◽  
Temporally Correlated

<div> <div> <div> <p>The accurate characterization of the uncertainty associated with the estimation of tidal constituents is critical to provide accurate water level reconstructions and predictions. However, this represents a challenge in applications since the sparse sampling and finite series length prevent sharply distinguishing between the deterministic tidal signal and the stochastic fluctuations present in the ob- served records. Specifically, the presence of various unresolved sources of vari- ability (e.g., the tide-surge, tide-tide, and tide-river flow interactions, as well as errors and in-homogeneities associated with data measurements) results in sig- nificant broad-spectrum variability of the recorded signals, as well as harmonic analysis parameter modulations from sub-daily to decadal temporal scales. As a result, the residuals obtained after performing regression harmonic analysis are temporally correlated. Conventional methods for assessing the harmonic model uncertainty typically ignore this autocorrelation. A Monte Carlo exper- iment is used to evaluate the effect of neglecting the residual autocorrelation in the estimation of tidal constituent uncertainty. The estimation of regression parameter variability from three commonly used analytical techniques (from the UTide and NS Tide packages, and the IRLS method) and two residual resam- pling (moving-block and semi-parametric bootstrap) are compared. We show that conventional methods (e.g., UTide and the IRLS) may largely underesti- mate the parameter uncertainty when relying on simplified assumptions, such as normality and independence of the regression residuals. This may lead to in- correct assessments about the significance of one or more predictors. We showed improved performance by using the two bootstrap strategies and NS Tide, as a result of a better representation of the autocorrelation structure of residuals. The moving-block bootstrap approach provides a simple alternative that can be easily applied to a large range of (unknown) autocorrelation structures of the observed residuals.</p> </div> </div> </div>

A Versatile XRF Analytical System for Geochemical Exploration and Other Applications

1983 ◽  
Vol 27 ◽  
pp. 481-486 ◽  
Author(s):  
T. K. Smith
Keyword(s):  
Large Scale ◽  
Mineral Exploration ◽  
Analytical Techniques ◽  
Geochemical Analysis ◽  
Geochemical Exploration ◽  
Fourth Period ◽  
Conventional Methods ◽  
Analytical System ◽  
Geological Sciences ◽  
And Tungsten

For more than a decade the Institute of Geological Sciences has carried out large-scale geochemical analysis in pursuit of mineral exploration and regional geochemical reconnaissance programmes for the Department of Industry. Over this period an XRF analytical system has been developed to meet part of this requirement for multielement data. The elements of interest range from the fourth period to uranium, and have become more numerous as exploration and analytical techniques have expanded. In particular, additions have been made of those elements such as arsenic, molybdenum and tungsten which are more difficult of determination by conventional methods.

Assessment of genetic diversity in goat genetic groups of Kerala, (India) using morphobiometric markers

2018 ◽  
Author(s):  
G. Radhika ◽  
K. C. Raghavan ◽  
K. A. Mercey ◽  
C. Sunanda ◽  
P. M. Rojan
Keyword(s):  
Genetic Diversity ◽  
Discriminant Analysis ◽  
Analytical Techniques ◽  
Coat Colour ◽  
Canonical Discriminant Analysis ◽  
Morphological Data ◽  
Biometric Data ◽  
Boer Goat ◽  
Canonical Variables ◽  
Genetic Groups

Geographical isolation and human interventions resulted in formation of subpopulations among native breeds, which showed differences in morphological or biometric traits. Crossbreeding of indigenous goats with exotic breeds resulted in combining desirable characteristics of many breeds in a composite population. Malabari crossbreds (CB), which had the inheritance of Malabari, Saanen, Alpine and Boer goat breeds were available at University Goat Farm, Mannuthy, Kerala, India. The native goats of Kerala namely, Attappady Black (AB) and populations of Malabari goats from Kannur, Calicut, Thrissur and Malappuram districts (MK, MC, MT and MM) were analysed along with Malabari crossbreds (CB) for genetic diversity. Morphological data were collected from 1776 animals and biometric data from 572 animals representing six goat populations. Qualitative morphological traits analysed were coat colour, presence or absence of horns, tassels, beard, pattern of ear and hair at forequarters and hindquarters. Quantitative biometric traits assessed were chest girth, height at withers, body length and body weight collected from female animals of one to three years of age. Least squares means calculated from SPSS, canonical discriminant analysis by CANDISC, Mahalanobis distance and dendrogram constructed by PROC CLUSTER were used to analyse biometric variables. Canonical discriminant analysis conducted for biometric data identified three statistically significant canonical variables (P less than 0.0001), with CAN1 explaining 57.2 per cent of total variance. Multivariate analytical techniques thus confirmed the existence of six different populations. The discriminatory capacity of biometric variables chosen for the study was also justified.

scholarly journals The phylogenetic relationships of geoemydid turtles from the Eocene Messel Pit Quarry: a first assessment using methods for continuous and discrete characters

PeerJ ◽  
2021 ◽  
Vol 9 ◽  
pp. e11805
Author(s):  
Eduardo Ascarrunz ◽  
Julien Claude ◽  
Walter G. Joyce
Keyword(s):  
Bayesian Methods ◽  
Molecular Data ◽  
Morphological Data ◽  
Bootstrap Support ◽  
Reference Tree ◽  
Quantitative Analyses ◽  
Overall Performance ◽  
Systematic Relationships ◽  
Western European ◽  
Messel Pit

The geoemydid turtles of the Eocoene Messel Pit Quarry of Hesse, Germany, are part of a rich Western European fossil record of testudinoids. Originally referred to as “Ocadia” kehreri and “Ocadia” messeliana, their systematic relationships remain unclear. A previous study proposed that a majority of the Western European geoemydids, including the Messel geoemydids, are closely related to the Recent European representatives of the clade Mauremys. Another study hypothesised that the Western European geoemydid fauna is more phylogenetically diverse, and that the Messel geoemydids are closely related to the East Asian turtles Orlitia and Malayemys. Here we present the first quantitative analyses to date that investigate this question. We use continuous characters in the form of ratios to estimate the placement of the Messel geoemydids in a reference tree that was estimated from molecular data. We explore the placement error obtained from that data with maximum likelihood and Bayesian methods, as well as linear parsimony in combination with discrete characters. We find good overall performance with Bayesian and parsimony analyses. Parsimony performs even better when we also incorporated discrete characters. Yet, we cannot pin down the position of the Messel geoemydids with high confidence. Depending on how intraspecific variation of the ratio characters is treated, parsimony favours a placement of the Messel fossils sister to Orlitia borneensis or sister to Geoemyda spengleri, with weak bootstrap support. The latter placement is suspect because G. spengleri is a phylogenetically problematic species with molecular and morphological data. There is even less support for placements within the Mauremys clade.

Systematics of the Australian orb-weaving spider genus Demadiana with comments on the generic classification of the Arkyinae (Araneae:Araneidae)

2010 ◽  
Vol 24 (2) ◽  
pp. 139 ◽  
Author(s):  
Volker W. Framenau ◽  
Nikolaj Scharff ◽  
Mark S. Harvey
Keyword(s):  
Phylogenetic Analysis ◽  
Type Species ◽  
Species Level ◽  
Junior Synonym ◽  
Data Matrix ◽  
Morphological Data ◽  
Australian Species ◽  
Systematic Relationships ◽  
Australasian Region

The orb-weaving spider subfamily Arkyinae L. Koch, 1872 is exclusively found in the Australasian region and its taxonomy and the systematic relationships within and between genera of this subfamily are poorly understood. We here revise the arkyine genus Demadiana Strand, 1929 to include six Australian species, four of which are described as new: Demadiana simplex (Karsch, 1878) (type species), D. carrai, sp. nov., D. cerula (Simon, 1908), comb. nov., D. complicata, sp. nov., D. diabolus, sp. nov., and D. milledgei, sp. nov. A phylogenetic analysis based on an updated araneid morphological data matrix including 57 genera of orb-weaving spiders identified Demadiana as a member of the araneid subfamily Arkyinae. A separate phylogenetic analysis for the genus at the species level showed little resolution within Demadiana, but did identify a monophyletic Demadiana supported by three putative synapomorphies: small unique setal pits with spherical sockets covering the carapace, sternum and the bases of the paturon (chelicerae), an extreme elongation of the trumpet-like aggregate spigots of the posterior lateral spinnerets and a distinct curvature of the embolus. We detail several new generic and species synonymies within Arkyinae. Aerea Urquhart, 1891 (type species Aerea alticephala Urquhart, 1891) and Neoarchemorus Mascord, 1968 (type species N. speechleyi Mascord, 1968) are regarded as junior synonyms of Arkys Walckenaer, 1837 (type species A. lancearius Walckenaer, 1837), resulting in Arkys speechleyi (Mascord, 1968), comb. nov. Aerea magnifica Urquhart, 1893 and Archemorus simsoni Simon, 1893 are regarded as junior synonyms of Aerea alticephala Urquhart, 1891, and Arkys nitidiceps Simon, 1908 is proposed as a junior synonym of Arkys walckenaeri Simon, 1879.

Systematic relationships of Nematomorpha based on molecular and morphological data

2005 ◽  
Vol 121 (4) ◽  
pp. 357-364 ◽  
Author(s):  
Christoph Bleidorn ◽  
Andreas Schmidt-Rhaesa ◽  
James R. Garey
Keyword(s):  
Morphological Data ◽  
Systematic Relationships

PHYLOGENY AND CLASSIFICATION OF THE MARCHANTIOPHYTA

2009 ◽  
Vol 66 (1) ◽  
pp. 155-198 ◽  
Author(s):  
B. Crandall-Stotler ◽  
R. E. Stotler ◽  
D. G. Long
Keyword(s):  
Molecular Phylogenetics ◽  
Classification Scheme ◽  
Morphological Data ◽  
Phylogenetic Classification ◽  
The Past ◽  
Systematic Relationships

Input from molecular phylogenetics in the past five years has substantially altered concepts of systematic relationships among liverworts. While these studies have confirmed the monophyly of phylum Marchantiophyta, they have demonstrated that many previously recognised ranks within the hierarchy are unnatural and in need of modification. Changes in the ranks of suborder and above have been proposed by various workers, but modifications in the circumscription of genera and families are still required. A comprehensive, phylogenetic classification scheme that integrates morphological data with molecular hypotheses is presented. The scheme includes diagnoses and publication citations for all names above the rank of genus. All currently recognised genera are listed alphabetically in their respective families; subfamilies are not indicated. Major modifications and novel alignments of taxa are thoroughly discussed, with pertinent references provided. Jungermanniaceae is redefined and Solenostomataceae fam. nov. is formally described to accommodate some of the genera excluded from it.

The Use of Advanced Analytical Techniques for Characterization of the Chemical, Physical, and Crystallographic Nature of a Surface

1973 ◽  
Vol 31 ◽  
pp. 132-133 ◽  
Author(s):  
R. E. Herfert
Keyword(s):  
Surface Characterization ◽  
Analytical Techniques ◽  
X Ray Diffraction ◽  
Depth Of Penetration ◽  
X Ray ◽  
The Past ◽  
Transmission Electron ◽  
Scanning Electron

Studies of the nature of a surface, either metallic or nonmetallic, in the past, have been limited to the instrumentation available for these measurements. In the past, optical microscopy, replica transmission electron microscopy, electron or X-ray diffraction and optical or X-ray spectroscopy have provided the means of surface characterization. Actually, some of these techniques are not purely surface; the depth of penetration may be a few thousands of an inch. Within the last five years, instrumentation has been made available which now makes it practical for use to study the outer few 100A of layers and characterize it completely from a chemical, physical, and crystallographic standpoint. The scanning electron microscope (SEM) provides a means of viewing the surface of a material in situ to magnifications as high as 250,000X.

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