Unrooted trees for numerical taxonomy

It is common to represent taxonomic hierarchies of related objects (such as similar plant or animal species or languages of the same family) by rooted trees with labelled terminal vertices which represent the objects. The multivariate data comparing numerous characteristics of the objects is first reduced to indices of similarity (or more often of dissimilarity) between each pair of objects. These are used to classify the objects into groups which are then depicted on a tree. This paper shows that an unrooted tree with labelled terminal vertices may provide a better representation of the relationships between the objects because the similarity indices are required to conform to fewer restrictions. Also for a given number of terminal vertices, there are fewer unrooted than rooted trees so that studies using probability distributions of trees or seeking the most suitable tree to represent the data are more practicable.

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Unrooted trees for numerical taxonomy

Journal of Applied Probability ◽

10.2307/3212580 ◽

1974 ◽

Vol 11 (1) ◽

pp. 32-42 ◽

Cited By ~ 41

Author(s):

Annette J. Dobson

Keyword(s):

Numerical Taxonomy ◽

Animal Species ◽

Probability Distributions ◽

Multivariate Data ◽

Rooted Trees ◽

Unrooted Tree ◽

Similarity Indices ◽

Indices Of Similarity

It is common to represent taxonomic hierarchies of related objects (such as similar plant or animal species or languages of the same family) by rooted trees with labelled terminal vertices which represent the objects. The multivariate data comparing numerous characteristics of the objects is first reduced to indices of similarity (or more often of dissimilarity) between each pair of objects. These are used to classify the objects into groups which are then depicted on a tree.This paper shows that an unrooted tree with labelled terminal vertices may provide a better representation of the relationships between the objects because the similarity indices are required to conform to fewer restrictions. Also for a given number of terminal vertices, there are fewer unrooted than rooted trees so that studies using probability distributions of trees or seeking the most suitable tree to represent the data are more practicable.

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Phenotypic identification and numerical taxonomy of pigmented bacteria isolated from marine and freshwater aquatic at Yogyakarta, Indonesia

Digital Press Physical Sciences and Engineering ◽

10.29037/digitalpress.11220 ◽

2018 ◽

Vol 1 ◽

pp. 00003

Author(s):

Fitri Indriana Susanti ◽

Endah Retnaningrum

Keyword(s):

Numerical Taxonomy ◽

Arithmetic Mean ◽

Group Method ◽

Phenetic Analysis ◽

Biochemical Tests ◽

Phenotypic Data ◽

Pair Group ◽

Similarity Indices ◽

Pigmented Bacteria ◽

Key Characters

Numerical phenetic analysis was used to compare phenotypic data obtained from 6 isolates of pigmented bacteria strains taken from marine and river aquatic. Each strain was tested for 120 characters, analysed using the simple matching (SSM) and Jaccard (SJ) similarity indices with unweighted pair-group method with arithmetic mean (UPGMA) clustering method. All of the strains classified into two clusters, cluster A as marine pigmented bacteria and cluster B as river pigmented bacteria. Differences were observed between the dendrograms derived from the SSM and SJ. Presence of bacteriochlorophyll–a (Bchl–a), carotenoids, as well as other biochemical tests of three marine pigmented strains were in match with key characters of the genera Roseobacter, Roseateles, and Erythrobacter. Three of river pigmented strains were identified as Xanthobacter, Flavobacterium, and Pseudomonas. It was proved that the marine and river pigmented bacteria isolates showed a relative phenotypically distance. It was clearly seen that the phenetic approach was a necessary tool to delimitate and identify the pigmented bacteria from different habitats.<o:p></o:p>

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Constant Rate Distributions on Partially Ordered Sets

Journal of Probability and Statistics ◽

10.1155/2010/675754 ◽

2010 ◽

Vol 2010 ◽

pp. 1-21

Author(s):

Kyle Siegrist

Keyword(s):

Failure Rate ◽

Algebraic Structure ◽

Point Processes ◽

Probability Distributions ◽

Partially Ordered Sets ◽

Rooted Trees ◽

Ordered Sets ◽

Partially Ordered ◽

Constant Rate

We consider probability distributions with constant rate on partially ordered sets, generalizing distributions in the usual reliability setting that have constant failure rate. In spite of the minimal algebraic structure, there is a surprisingly rich theory, including moment results and results concerning ladder variables and point processes. We concentrate mostly on discrete posets, particularly posets whose graphs are rooted trees. We pose some questions on the existence of constant rate distributions for general discrete posets.

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Asteroid and Comet Impact Speeds upon Mars: Significance for Panspermia and the Supply of Organics

International Astronomical Union Colloquium ◽

10.1017/s0252921100014718 ◽

1997 ◽

Vol 161 ◽

pp. 197-201 ◽

Cited By ~ 1

Author(s):

Duncan Steel

Keyword(s):

Probability Distributions ◽

Regions Of Interest ◽

Significant Fraction ◽

Organic Chemicals ◽

Impact Speed ◽

The Mean ◽

The Impact

AbstractWhilst lithopanspermia depends upon massive impacts occurring at a speed above some limit, the intact delivery of organic chemicals or other volatiles to a planet requires the impact speed to be below some other limit such that a significant fraction of that material escapes destruction. Thus the two opposite ends of the impact speed distributions are the regions of interest in the bioastronomical context, whereas much modelling work on impacts delivers, or makes use of, only the mean speed. Here the probability distributions of impact speeds upon Mars are calculated for (i) the orbital distribution of known asteroids; and (ii) the expected distribution of near-parabolic cometary orbits. It is found that cometary impacts are far more likely to eject rocks from Mars (over 99 percent of the cometary impacts are at speeds above 20 km/sec, but at most 5 percent of the asteroidal impacts); paradoxically, the objects impacting at speeds low enough to make organic/volatile survival possible (the asteroids) are those which are depleted in such species.

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Author response for "Perceptual rivalry across animal species"

10.1002/cne.24939/v3/response1 ◽

2020 ◽

Author(s):

Olivia Carter ◽

Bruno Swinderen ◽

David Leopold ◽

Shaun Collin ◽

Alex Maier

Keyword(s):

Animal Species ◽

Author Response ◽

Perceptual Rivalry

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Anchoring Fibrils in Arterial Endothelium

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100063287 ◽

1969 ◽

Vol 27 ◽

pp. 274-275

Author(s):

A. Trillo

Keyword(s):

Carotid Arteries ◽

Animal Species ◽

Cell Layer ◽

Present Communication ◽

Internal Elastic Lamina ◽

Endothelial Cell Layer ◽

Structural Details ◽

Rats And Mice ◽

Arterial Endothelium ◽

Elastic Lamina

There are conflicting reports regarding some fine structural details of arteries from several animal species. Buck denied the existence of a sub-endothelial space, while Karrer and Keech described a space of variable width which separates the endothelium from the underlying internal elastic lamina in aortas of aging rats and mice respectively.The present communication deals with the ultrastrueture of the interface between the endothelial cell layer and the internal elastic lamina as observed in carotid arteries from rabbits of varying ages.

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Ultrastructure and Drug Metabolism in the Developing Guinea Pig

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100073131 ◽

1973 ◽

Vol 31 ◽

pp. 538-539

Author(s):

W. Kuenzig ◽

M. Boublik ◽

J.J. Kamm ◽

J.J. Burns

Keyword(s):

Guinea Pig ◽

Metabolic Activity ◽

Animal Species ◽

Adult Animal ◽

Smooth Endoplasmic Reticulum ◽

Fetal Life ◽

Mixed Function Oxidase ◽

Cytochrome P 450 ◽

Microsomal Mixed Function Oxidase ◽

Mixed Function Oxidase Activity

Unlike a variety of other animal species, such as the rabbit, mouse or rat, the guinea pig has a relatively long gestation period and is a more fully developed animal at birth. Kuenzig et al. reported that drug metabolic activity which increases very slowly during fetal life, increases rapidly after birth. Hepatocytes of a 3-day old neonate metabolize drugs and reduce cytochrome P-450 at a rate comparable to that observed in the adult animal. Moreover the administration of drugs like phenobarbital to pregnant guinea pigs increases the microsomal mixed function oxidase activity already in the fetus.Drug metabolic activity is, generally, localized within the smooth endoplasmic reticulum (SER) of the hepatocyte.

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Further Studies on the Ultrastructure of Harderian Gland in Adult Rats

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100051451 ◽

1974 ◽

Vol 32 ◽

pp. 288-289

Author(s):

Alfredo Feria-Velasco ◽

Guadalupe Tapia-Arizmendi

Keyword(s):

Fine Structure ◽

Domestic Fowl ◽

Animal Species ◽

Acinar Cells ◽

Harderian Gland ◽

Myoepithelial Cells ◽

The Other ◽

Albino Rats ◽

Adult Rats ◽

Cell Components

The fine structure of the Harderian gland has been described in some animal species (hamster, rabbit, mouse, domestic fowl and albino rats). There are only two reports in the literature dealing on the ultrastructure of rat Harderian gland in adult animals. In one of them the author describes the myoepithelial cells in methacrylate-embbeded tissue, and the other deals with the maturation of the acinar cells and the formation of the secretory droplets. The aim of the present work is to analize the relationships among the acinar cell components and to describe the two types of cells located at the perifery of the acini.

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The Contribution of Pavlov's Typology of CNS Properties to Personality Research

European Psychologist ◽

10.1027/1016-9040.2.2.125 ◽

1997 ◽

Vol 2 (2) ◽

pp. 125-138 ◽

Cited By ~ 17

Author(s):

Jan Strelau

Keyword(s):

Soviet Union ◽

Former Soviet Union ◽

Animal Species ◽

Special Significance ◽

The West ◽

Personality Dimensions ◽

Personality Research ◽

Personality Theories ◽

Strength Of Excitation ◽

Point Of Departure

This paper presents Pavlov's contribution to the development of biological-oriented personality theories. Taking a short description of Pavlov's typology of central nervous system (CNS) properties as a point of departure, it shows how, and to what extent, this typology influenced further research in the former Soviet Union as well as in the West. Of special significance for the development of biologically oriented personality dimensions was the conditioned reflex paradigm introduced by Pavlov for studying individual differences in dogs. This paradigm was used by Russian psychologists in research on types of nervous systems conducted in different animal species as well as for assessing temperament in children and adults. Also, personality psychologists in the West, such as Eysenck, Spence, and Gray, incorporated the CR paradigm into their theories. Among the basic properties of excitation and inhibition on which Pavlov's typology was based, strength of excitation and the basic indicator of this property, protective inhibition, gained the highest popularity in arousaloriented personality theories. Many studies have been conducted in which the Pavlovian constructs of CNS properties have been related to different personality dimensions. In current research the behavioral expressions of the Pavlovian constructs of strength of excitation, strength of inhibition, and mobility of nervous processes as measured by the Pavlovian Temperament Survey (PTS) have been related to over a dozen of personality dimensions, mostly referring to temperament.

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Animals as Social Objects

European Psychologist ◽

10.1027/1016-9040/a000268 ◽

2016 ◽

Vol 21 (3) ◽

pp. 206-217 ◽

Cited By ~ 10

Author(s):

Verónica Sevillano ◽

Susan T. Fiske

Keyword(s):

Social Perception ◽

Animal Species ◽

Social Groups ◽

Social Responses ◽

Content Model ◽

Stereotype Content ◽

Nonhuman Animals ◽

Behavioral Tendencies ◽

Similarities And Differences ◽

Sphere Of Influence

Abstract. Nonhuman animals are typically excluded from the scope of social psychology. This article presents animals as social objects – targets of human social responses – overviewing the similarities and differences with human targets. The focus here is on perceiving animal species as social groups. Reflecting the two fundamental dimensions of humans’ social cognition – perceived warmth (benign or ill intent) and competence (high or low ability), proposed within the Stereotype Content Model ( Fiske, Cuddy, Glick, & Xu, 2002 ) – animal stereotypes are identified, together with associated prejudices and behavioral tendencies. In line with human intergroup threats, both realistic and symbolic threats associated with animals are reviewed. As a whole, animals appear to be social perception targets within the human sphere of influence and a valid topic for research.

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