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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
51

Effects of acanthocephalan parasites on colour and carotenoid quantities of their intermediate host Gammarus lacustris in the context of variable lake productivity

Balanean, Leontin 11 1900 (has links)
I studied the effects of Polymorphus paradoxus Connell and Corner and Polymorphus marilis Van Cleave on colour and carotenoid quantities of their host amphipod Gammarus lacustris G.O. Sars in seven lakes in Alberta, Canada, that differed in productivity. Polymorphus marilis induced pigmentation dystrophy and a higher degree of blueness in both amphipod sexes than did P. paradoxus. Colour shifted toward lighter, bluer and greener tones, denoting less carotenoids, in amphipods parasitized by P. marilis. This is the first study to measure host-colour changes induced by parasites using consistent, repeatable digital analysis. Maximum carotenoid quantities were reached in hypereutrophic lakes where parasite-induced colour changes were also generally minimal. I developed regression models that accurately predict carotenoid quantities in amphipods by their colour, parasite status and water chemistry. This is the first study showing that carotenoid quantities and parasite-induced colour change in crustaceans depend on lake productivity. / Ecology
52

Effects of acanthocephalan parasites on colour and carotenoid quantities of their intermediate host Gammarus lacustris in the context of variable lake productivity

Balanean, Leontin 11 1900 (has links)
I studied the effects of Polymorphus paradoxus Connell and Corner and Polymorphus marilis Van Cleave on colour and carotenoid quantities of their host amphipod Gammarus lacustris G.O. Sars in seven lakes in Alberta, Canada, that differed in productivity. Polymorphus marilis induced pigmentation dystrophy and a higher degree of blueness in both amphipod sexes than did P. paradoxus. Colour shifted toward lighter, bluer and greener tones, denoting less carotenoids, in amphipods parasitized by P. marilis. This is the first study to measure host-colour changes induced by parasites using consistent, repeatable digital analysis. Maximum carotenoid quantities were reached in hypereutrophic lakes where parasite-induced colour changes were also generally minimal. I developed regression models that accurately predict carotenoid quantities in amphipods by their colour, parasite status and water chemistry. This is the first study showing that carotenoid quantities and parasite-induced colour change in crustaceans depend on lake productivity. / Ecology
53

Effects of acanthocephalan parasites on colour and carotenoid quantities of their intermediate host Gammarus lacustris in the context of variable lake productivity

Balanean, Leontin 11 1900 (has links)
I studied the effects of Polymorphus paradoxus Connell and Corner and Polymorphus marilis Van Cleave on colour and carotenoid quantities of their host amphipod Gammarus lacustris G.O. Sars in seven lakes in Alberta, Canada, that differed in productivity. Polymorphus marilis induced pigmentation dystrophy and a higher degree of blueness in both amphipod sexes than did P. paradoxus. Colour shifted toward lighter, bluer and greener tones, denoting less carotenoids, in amphipods parasitized by P. marilis. This is the first study to measure host-colour changes induced by parasites using consistent, repeatable digital analysis. Maximum carotenoid quantities were reached in hypereutrophic lakes where parasite-induced colour changes were also generally minimal. I developed regression models that accurately predict carotenoid quantities in amphipods by their colour, parasite status and water chemistry. This is the first study showing that carotenoid quantities and parasite-induced colour change in crustaceans depend on lake productivity. / Ecology
54

Diagnostic colours of emotions

Gohar Kadar, Navit January 2008 (has links)
Doctor of Philosophy / This thesis investigates the role of colour in the cognitive processesing of emotional information. The research is guided by the effect of colour diagnosticity which has been shown previously to influence recognition performance of several types of objects as well as natural scenes. The research presented in Experiment 1 examined whether colour information is considered a diagnostic perceptual feature of seven emotional categories: happiness, sadness, anger, fear, disgust, surprise and neutral. Participants (N = 119), who were naïve to the specific purpose and expectations of the experiment, chose colour more than any other perceptual quality (e.g. shape and tactile information) as a feature that describes the seven emotional categories. The specific colour features given for the six basic emotions were consistently different from those given to the non-emotional neutral category. While emotional categories were often described by chromatic colour features (e.g. red, blue, orange) the neutral category was often ascribed achromatic colour features (e.g. white, grey, transparent) as the most symptomatic perceptual qualities for its description. The emotion 'anger' was unique in being the only emotion showing an agreement higher that 50% of the total given colour features for one particular colour - red. Confirming that colour is a diagnostic feature of emotions led to the examination of the effect of diagnostic colours of emotion on recognition memory for emotional words and faces: the effect, if any, of appropriate and inappropriate colours (matched with emotion) on the strength of memory for later recognition of faces and words (Experiments 2 & 3). The two experiments used retention intervals of 15 minutes and one week respectively and the colour-emotion associations were determined for each individual participant. Results showed that regardless of the subject’s consistency level in associating colours with emotions, and compared with the individual inappropriate or random colours, individual appropriate colours of emotions significantly enhance recognition memory for six basic emotional faces and words. This difference between the individual inappropriate colours or random colours and the individual appropriate colours of emotions was not found to be significant for non-emotional neutral stimuli. Post hoc findings from both experiments further show that appropriate colours of emotion are associated more consistently than inappropriate colours of emotions. This suggests that appropriate colour-emotion associations are unique both in their strength of association and in the form of their representation. Experiment 4 therefore aimed to investigate whether appropriate colour-emotion associations also trigger an implicit automatic cognitive system that allows faster naming times for appropriate versus inappropriate colours of emotional word carriers. Results from the combined Emotional-Semantic Stroop task confirm the above hypothesis and therefore imply that colour plays a substantial role not only in our conceptual representations of objects but also in our conceptual representations of basic emotions. The resemblance of the present findings collectively to those found previously for objects and natural scenes suggests a common cognitive mechanism for the processing of emotional diagnostic colours and the processing of diagnostic colours of objects or natural scenes. Overall, this thesis provides the foundation for many future directions of research in the area of colour and emotion as well as a few possible immediate practical implications.
55

Facade colour and aesthetic response: Examining patterns of response within the context of urban design and planning policy in Sydney

O'Connor, Zena January 2008 (has links)
Doctor of Philosophy (PhD) / The overall aim of this research was to examine aesthetic response to façade colour. Drawing on a range of theories and studies from environment-behaviour studies (EBS), Nasar’s (1994) probabilistic model of aesthetic response to building attributes provided a theoretical framework within which to examine patterns of response. Prompted by the Development Control Plan for Sydney Regional Environmental Plan: Sydney Harbour Catchment (NSWDOP, 2005), this research also linked its aims and methods to planning policy in Sydney. The main research questions focussed on whether changes in aesthetic response are associated with variations in façade colour; and whether changes in judgements about building size, congruity and preference are associated with differences in façade colour. A quasi-experimental research design was used to examine patterns of aesthetic response. The independent variable was represented by four façade colours in two classifications. An existing process, environmental colour mapping, was augmented with digital technology and used to isolate, identify and manipulate the independent variable and for preparation of visual stimuli (Foote, 1983; Iijima, 1995; Lenclos, 1977; Porter, 1997). Façade colour classifications were created from extant colour theories (including those of Albers, 1963; Hard & Sivik, 2001 and Itten, 1961). The façade colour classifications were further developed using F-sort and Q-sort methodology (Amin, 2000; Miller, Wiley & Wolfe, 1986; Stephenson, 1953). Ten dependent variables, linked to overall aesthetic response, were drawn from studies relating to environmental evaluation, building congruity and preference (Groat, 1992; Janssens, 2001; Russell, 1988; Russell, 2003; Russell, Ward & Pratt, 1981; Wohlwill & Harris, 1980). The dependent variables were presented in the form of a semantic differential rating scale and a sample group of 288 evaluated the visual stimuli. The Latin-square technique was used for the controlled presentation of visual stimuli. Factor analysis, correlation analysis and analysis of variance were applied to the data. The findings indicate that variations in aesthetic response are associated with differences in façade colour. Judgements about building size varied by up to 5% and buildings featuring contrasting façade colours were judged to be larger and more dominant. Judgements about a building’s congruity varied by up to 13% and buildings that featured harmonious colours were considered to be more congruous. Preference varied and harmonious façade colours were not necessarily preferred over contrasting façade colours. The outcomes from this research suggest that a new approach to façade colour within the context of planning policy may be appropriate. A model of façade colour evaluation is presented and, unlike current planning guidelines, the model allows for a participatory approach to façade colour evaluation and specification. The model allows for factors that may influence aesthetic response to façade colour (such as contextual, perceptual and idiographic factors) as well as variation in architectural expression with respect to façade colour.
56

Variation of flour colour in Western Australia adapted wheat: comparative genomics, molecular markers and QTL analysis

kryan@ccg.murdoch.edu.au, Karon Magdalene Leanne Ryan January 2005 (has links)
The yellowness of flour colour ranges is an important quality trait in wheat for end-use products and is determined by the accumulation of carotenoids in the endosperm. The aims of this study were to develop EST-based molecular markers for genes encoding enzymes of the carotenoid biosynthetic pathway leading to xanthophyll accumulation and identify quantitative trait loci for flour colour (b*) and xanthophyll content in Western Australian adapted germplasm. A novel bioinformatic strategy was developed to identify rice genes encoding key enzymes of the carotenoid biosynthetic pathway and to predict wheat orthologues on the short arm of chromosome 3 or long arm of chromosome 7. The bioinformatic strategy involved the identification of rice carotenoid genes on BAC/PAC contigs aligned to wheat mapped ESTs. Rice genes predicted to have wheat orthologues were selected based on ESTs mapping to regions on wheat homoeologous chromosomes 3 and 7 known to be involved in flour colour. The rice genes predicted to have wheat orthologues were Geranylgeranyltransferase I ƒÒ¡Vsubunit (GGT-Ibeta) and Rab geranylgeranyltransferase component A (RGGT-A) on the short arm of chromosome 3, Lycopene ƒÒ¡Vcylcase (LBC) on the long arm of chromosome 3 and Lycopene £`¡Vcylcase (LEC) on the long arm of chromosome 7. The prediction of these wheat orthologues provided the basis for development of EST-based molecular markers for detecting variation in xanthophyll content. Wheat ESTs with unknown chromosomal locations and having the highest similarity to GGT-Ibeta, RGGT-A and LBC were selected for the development of molecular markers. No EST homologues were identified for LEC and therefore this gene was not further considered. Orthology was confirmed by sequencing and deletion lines were used to confirm chromosomal locations. Two partial orthologues of GGT-Ibeta were identified on the short arms of chromosomes 3B and 3D. A partial orthologue of RGGT-A was mapped to the proximal regions of the short and long arms of chromosome 3B. At least two or more orthologues of LBC were identified from nullisomic-tetrasomic lines. An EST-based molecular marker for GGT-Ibeta was found to be involved in minor variation of xanthophyll content in a Westonia*2/Janz doubled haploid population. QTL analysis from three doubled haploid populations indicated variation in WA-adapted germplasm may be due to different alleles controlling flour colour. QTLs for b* and xanthophyll content were found to coincide on the short arms of chromosomes 3A, 4D, and 7B and the long arm of chromosomes 7A and 7B in WA-adapted germplasm. Homoeologous expression of regions controlling variation in b* and xanthophyll content on the long arm of chromosomes 7A and 7B suggests the shut-down of genes in the same region on chromosome 7D. The main outcome of this study is flour colour and identification of gene orthologues in wheat controlling variation in xanthophyll content is complex most likely because of the interaction of the carotenoid biosynthetic pathway with other pathways.
57

An investigation of the reliability and validity of the Luscher colour test.

Barnett, Adrian John. January 1975 (has links) (PDF)
Thesis (B.A. (Hons.))--University of Adelaide, Dept. of Psychology, 1976.
58

Colour patterns affecting the attack readiness in a Cichlid (Haplochromis burtoni, Pisces, Cichlidae)

Leong, Che-ying, Daisy. January 1970 (has links)
Thesis (Ph. D.)--University of Hong Kong, 1970. / Also available in print.
59

A Stroop investigation of colour categorisation

Laws, Glynis January 1993 (has links)
In order to assess Berlin and Kay's (1969) theory of linguistic universals and to test their proposal for an evolutionary hierarchy in the development of colour terms, linguists and anthropologists have sought reliable criteria on which to decide whether or not a colour term is "basic". Berlin and Kay's operational definition of basicness is essentially a list of linguistic criteria which emphasise the form, derivation and frequency of the word. The definition has been criticised for lack of theoretical justification and for operational difficulties. Research is reported which investigates the concept of basicness using the Stroop experiment, a method said to tap into the primitive operations of cognition (MacLeod, 1991). The experiments investigated the relationship between typicality and linguistic basicness in English; differences in the category structure for novices and experts; and the status of colour terms in Russian and Swahili, languages at different stages of the Berlin and Kay hierarchy. Results suggest that Stroop measures differentiate between colour processing and language effects. In particular, it is suggested that linguistic criteria neglect the underlying and essential link between language and colour categories and that linguistic basicness, according to the linguists' formulation, may not necessarily reflect category representation.
60

Computational mechanisms for colour and lightness constancy

Caplinger, Wayne Holmes January 1984 (has links)
Attributes of colour images have been found which allow colour and lightness constancy to be computed without prior knowledge of the illumination, even in complex scenes with three -dimensional objects and multiple light sources of different colours. The ratio of surface reflectance colour can be immediately determined between any two image points, however distant. It is possible to determine the number of spectrally independent light sources, and to isolate the effect of each. Reflectance edges across which the illumination remains constant can be correctly identified. In a scene illuminated by multiple distant point sources of distinguishalbe colours, the spatial angle between the sources and their brightness ratios can be computed from the image alone. If there are three or more sources then reflectance constancy is immediately possible without use of additional knowledge. The results are an extension of Edwin Land's Retinex algorithm. They account for previously unexplained data such as Gilchrist's veiling luminances and his single- colour rooms. The validity of the algorithms has been demonstrated by implementing them in a series of computer programs. The computational methods do not follow the edge or region finding paradigms of previous vision mechanisms. Although the new reflectance constancy cues occur in all normal scenes, it is likely that human vision makes use of only some of them. In a colour image all the pixels of a single surface colour lie in a single structure in flux space. The dimension of the structure equals the number of illumination colours. The reflectance ratio between two regions is determined by the transformation between their structures. Parallel tracing of edge pairs in their respective structures identifies an edge of constant illumination, and gives the lightness ratio of each such edge. Enhanced noise reduction techniques for colour pictures follow from the natural constraints on the flux structures.

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