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Structure-based Subfamily Classification of HomeodomainsTsai, Jennifer Ming-Jiun 30 July 2008 (has links)
Eukaryotic DNA-binding proteins mediate many important steps in embryonic development and gene regulation. Consequently, a better understanding of these proteins would hopefully allow a more complete picture of gene regulation to be determined. In this study, a structure-based subfamily classification of the homeodomain family of DNA-binding proteins was undertaken in order to determine whether sub-groupings of a protein family could be identified that corresponded to differences in specific function, and identification of subfamily-determining residues was performed in order to gain some insight on functional differences via analysis of the residue properties. Subfamilies appear to have different specific DNA binding properties, according to DNA profiles obtained from TRANSFAC [1] and other sources in the literature. Subfamily-specific residues appear to be frequently associated with the protein-DNA interface and may influence DNA binding via interactions with the DNA phosphate backbone; these residues form a conserved profile uniquely identifying each subfamily.
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Structure-based Subfamily Classification of HomeodomainsTsai, Jennifer Ming-Jiun 30 July 2008 (has links)
Eukaryotic DNA-binding proteins mediate many important steps in embryonic development and gene regulation. Consequently, a better understanding of these proteins would hopefully allow a more complete picture of gene regulation to be determined. In this study, a structure-based subfamily classification of the homeodomain family of DNA-binding proteins was undertaken in order to determine whether sub-groupings of a protein family could be identified that corresponded to differences in specific function, and identification of subfamily-determining residues was performed in order to gain some insight on functional differences via analysis of the residue properties. Subfamilies appear to have different specific DNA binding properties, according to DNA profiles obtained from TRANSFAC [1] and other sources in the literature. Subfamily-specific residues appear to be frequently associated with the protein-DNA interface and may influence DNA binding via interactions with the DNA phosphate backbone; these residues form a conserved profile uniquely identifying each subfamily.
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Investigation of Computer Vision Techniques for Object Classification on an Intelligent Wheelchair System for the Cognitively ImpairedOramasionwu, Paul 09 December 2013 (has links)
The purpose of this research was to investigate object classification algorithms for the application of wheelchair interaction with the environment for the cognitively impaired wheelchair user. Towards this end, top performing object classification algorithms were trained on images of the target object classes (chair, dresser, and sink/washbasin) obtained from the internet and tested on images of the target object classes obtain in the home and patient room environments; these algorithms were Locality-constrained Linear Coding (LLC) [1], Kernel Descriptors (KDES) [2], and Hierarchical Matching Pursuit (HMP) [3]. It was found that HMP achieved the highest over classification accuracy (71.3%) in the home environment and LLC achieved the greatest accuracy (85.0%) in the patient room environment. This research also sought to investigate the potential of active learning to improve upon the obtained classification performance. A maximum mean classification accuracy of 98.6% was achieved when active learning was applied.
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A chemotaxonomic study of the "Rutales" of Scholz (In Engler, Syllabus 12, 1964)Liau, Sally Sho-Hwa January 1970 (has links)
No description available.
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Investigation of Computer Vision Techniques for Object Classification on an Intelligent Wheelchair System for the Cognitively ImpairedOramasionwu, Paul 09 December 2013 (has links)
The purpose of this research was to investigate object classification algorithms for the application of wheelchair interaction with the environment for the cognitively impaired wheelchair user. Towards this end, top performing object classification algorithms were trained on images of the target object classes (chair, dresser, and sink/washbasin) obtained from the internet and tested on images of the target object classes obtain in the home and patient room environments; these algorithms were Locality-constrained Linear Coding (LLC) [1], Kernel Descriptors (KDES) [2], and Hierarchical Matching Pursuit (HMP) [3]. It was found that HMP achieved the highest over classification accuracy (71.3%) in the home environment and LLC achieved the greatest accuracy (85.0%) in the patient room environment. This research also sought to investigate the potential of active learning to improve upon the obtained classification performance. A maximum mean classification accuracy of 98.6% was achieved when active learning was applied.
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Biosystematics of the genus Impatiens in northeastern North America.Russell, Alina E. January 1976 (has links)
No description available.
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Anatomical and functional changes between terrestrial varanoid lizards and aquatic mosasaursDebraga, Michael January 1990 (has links)
The transition between terrestrial varanoid lizards and aquatic mosasaurs through the intermediate, semi-aquatic aigialosaurs is fully documented. Aigialosaurs are shown to possess a mosaic of mosasaurian (configuration of the skull, jaw and tail) and terrestrial varanoid characters (appendicular skeleton and trunk). / The taxonomic position of the Aigialosauridae within the superfamily Varanoidea is evaluated. Based on character states previously used to define the Varanoidea, neither the specific affinities of aigialosaurs nor the sister-group relationships of earlier members of the terrestrial varanoid assemblage can be securely established. For this reason, the specific character states involved have been reexamined and alternative hypotheses of relationship have been considered.
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Learning Mid-Level Features from Object Hierarchy for Image ClassificationAlbaradei, Somayah January 2014 (has links)
One of the most active research areas in computer vision is image classification. Although there have been many research efforts in this area, it remains a difficult problem, especially when the number of categories is large. Most of the previous work in image classification uses low-level image features. We believe low-level features ignore a lot of the semantic structures of the image classes. In this thesis, we go beyond simple low-level features and propose new approaches for constructing mid-level visual features for image classification. We represent an image using the outputs of a collection of binary classifiers. These binary classifiers are trained to differentiate pairs of object classes in an object hierarchy. Our feature representations implicitly capture the hierarchical structure in object classes. We show that our proposed approach outperforms other baseline methods in image classification.
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DNA sequence analysis of the rDNA ITS 1/2 region in the evolutionary delineation of the Pilobolaceae / DNA sequence analysis of the ribosomal DNA internal transcribed spacer one-two region in the evolutionary delineation of the PilobolaceaeGilmore, Luther Martin January 2006 (has links)
This project represents an initial examination of the evolutionary history of the genus Pilobolus, and provides a starting point for developing a method to accurately classify members of this genus using molecular genetics. The data analysis presented in this paper suggests a potential evolutionary path in which P. umbonatus and P. sphaerosporus diverged (along a common path) from an original generic ancestor early, but independently, from the evolutionary course taken by P. kleinii. Both Maximum Likelihood and parsimony analyses concur in the branch patterns. Additionally, formation of species-specific clades between samples of P. sphaerosporus, P. kleinii and P. umbonatus suggests that there may be markers present in the ITS sequence that can be used for the development of a molecular test for the classification of species within the genus Pilobolus.Ball State UniversityMuncie, IN 47306 / Department of Biology
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A study of the interrelationships of some Natal species of Senecio (Asteraceae/Compositae)Vincent, Leszek Paul Doroszynski. January 1984 (has links)
This dissertation presents the results of studies of the generic concept
of Senecio and the subsequent testing of the hypothes is: that many of
the species of Senecio in Natal are congeneric with Senecio L. sensu
stricto. The sample of taxa studied consisted of 87 Natal senecios, 5
Cape heterochromous senecios and 10 non-southern African senecios,
including the type of the genus, S. vulgaris L. Also included in the
study were 5 species from taxonomically closely related genera in the
tribe Senecioneae and two senecios of uncertain taxonomic position.
The phenotype of these taxa was investigated with respect to a large
number of morphological and micromorphological characters (126) and the
data obtained were analysed neurally and numerically.
Aspects of the pollen micromorphology, of all the taxa studied, were
also investigated using the scanning electron microscope.
A review of the chemical complement of all the taxa studied.
particularly with respect to terpenes and pyrrolizidine alkaloids, was
also undertaken.
Six characters were selected as being taxonomically significant with
respect to elucidating the generic concept of Senecio. A further 31
characters and the aforementioned 6, were selected as .being
taxonomically significant with respect to elucidating the
interrelationships of the Natal senecios and all the senecios studied. The generic concept of Senecio has been re-circumscribed and the generic
status of each of the senecios studied has been tested according to this
concept of Senecio sensu Vincent. In the light of my concept of
Senecio, the following species are excluded from Senecio sensu Vincent:
S. barbertonicus Klatt, S. cissampelinus (DC.) Schultz Bipontinus,
S. fulgens (J.D. Hooker) Nicholson, S. helminthioides (Schultz
Bipontinus) Hilliard, S. hockii De Wild. & Muschl., S. medley-woodii
Hutchinson, S. radicans (L.L) Schultz Bipontinus, S. syringifolius
O.Hoffm., S. tamoides DC., S. transvaalensis Bolus and S. viminalis
Bremekamp. Senecio brevilorus Hilliard, S. seminiveus Wood & Evans and
S. tanacetopsis Hilliard are considered to be peripheral to Senecio s.
str. sensu Vincent, and are included in Senecio s. lat. sensu Vincent.
The hypothesis regarding the generic status of the Natal senecios has
been accepted, subsequent to the circumscription of Senecio s. str.
sensu Vincent.
Estimates of the phenetic affinity of all the members of Senecio sensu
stricto sensu Vincent, included in this study, have been made. The
majority of the Natal senecios, while clearly being members of Senecio
s. str. sensu Vincent, are distinct from virtually all the Cape and
non-southern African senecios studied. Many of the non-yellow (purple)
Natal senecios form clearly allied groups which are distinct from the
groups (clusters) composed of yellow senecios. The taxonomic position
of several taxa is questioned, in the light of the cluster analyses. The evidence from the palynological studies neither contradicts nor
supports the proposed infrageneric interrelationships, with respect to
the Natal members of Senecios. str. sensu Vincent. The evidence also
neither contradicts nor supports the proposed interrelationships between
the Natal, the Cape and the non-southern African members of Senecios.
str. sensu Vincent.
The terpene and pyrrolizidine chemistry of many of many of the senecios
studied is characterised by the presence of furanoeremophilanes.
Eremophilanes also occur and are particularly associated with a number
of non-yellow (purple) senecios. Pyrrolizidine alkaloids are not
ubiquitous amongst the senecios studied, while some senecios appear to
only synthesise pyrrolizidine alKaloids.
The review of the errpene and pyrrolizidine chemistry of the senecios
investigated, illustrates how our knowledge at or near the level of
analytic characters is far from complete. However, we have definitely
progressed from the synthetic level of character use. Nevertheless, the
relationships between the members of Senecios. str. sensu Vincent,
could not be evaluated in the light of the individual chemical
complement of terpenes and pyrrolizidine alkaloids, because of a lack of
information. An hypothesis of the chemical evolution within the
Senecioneae is tested with in Senecios. str. sensu Vincent .
Before any taxonomic changes are made to t he current composition of
Senecio L., the concept of Senecio L. s. str. sensu Vincent, needs to be
tested against a far wider sample of the genus. / Thesis (Ph.D.)-University of Natal, Pietermaritzburg, 1984.
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