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This research has investigated the modification of cotton fabric and pigment dyeing system in order to improve the colouration properties, such as rub fastness, wash fastness, colour strength and fabric handle of the textile material. It involved four different approaches based on pre-cationization of the fabric, incorporation of crosslinkers into the binder formulation, UVO pre-treatment of the fabric, and wet fluorocarbon treatment and dry plasma polymerisation treatments.It has been reported that the Matrix OSD pigment dyeing system offers benefits in terms of processing cost and environmental impact and from the initial studies it was apparent that while dry rub fastness, mechanical rigidity and washing performance were generally acceptable the wet rub fastness of the printed fabrics presented a technical challenge. Therefore in this study the colour wet rub fastness was regarded as the main performance indicator to be targeted and improved. Cationizing the cotton fabrics prior to pigment dyeing improved the wet rub fastness performance of the Matrix OSD dyeing system, while the other fastness properties were in general unchanged. Similarly crosslinking treatments enhanced the colour fastness performance, due to the improvement of the bonding between the binder and fabrics. The crosslinking/crease resist pre-treatment offers better performance than the combined application method in terms of improving the wet rub fastness. Surface modification of textile materials is able to modify the textile wettability, adhesion, dyeability and handle and therefore has been studied with a view to improving the durability of the surface pigment dyed coating. However in this study the benefits of a UV/Ozone (UVO) pre-treatment previously observed for other long liquor fabric dyeing studies of textiles was not observed and it was established that the pigment dyeing performance was reduced after the sensitised photo-oxidation treatment. The investigation demonstrated that the fluorocarbon treatments had a beneficial effect on colour wash fastness and wet rub fastness, while dry rub fastness was marginally reduced at higher fluorocarbon application levels. Different fluorocarbons were examined in this study, and the aftertreatment with Shield F-01 and Shield extender FCD offered the best results. A range of plasma pre-treatments prior to pigment dyeing were also examined but only a marginal benefit on the colour fastness properties and to some extent slightly decreased dry rub fastness was observed. In contrast the plasma after-treatments, using both argon (Ar) and nitrogen (N2) atmospheres, improved the fastness, particularly wet fastness, particularly when the binder heat curing process was before plasma after-treatment.

Signal reception and production form the basis of animal communication, and are largely constrained by environmental biophysical factors such as environmental light. However, the role of environmental light in producing variation in either signal reception or production has not been fully investigated. Using two distinct environmental light treatments, as well as a third treatment for a sampling of adults, I recorded corneal electroretinograms, lens transmission, and spectral reflectance of the body pattern of juvenile and adult Nile tilapia to chart the effect of environmental light on visual sensitivity and body colouration throughout ontogeny. Environmental light had an age-dependent effect on spectral sensitivity and an age-independent effect on spectral reflectance. Spectral sensitivity in juveniles reared under a broad-spectrum light treatment and a red-shifted light treatment differed mostly at short wavelengths, where the irradiance of the two environmental light treatments differed the most. In contrast, adults reared under the two environmental light treatments did not differ in spectral sensitivity. Lens transmission did not differ significantly between environmental light treatments, indicating that differences in spectral sensitivity of juveniles originated in the retina. Both juveniles and adults reared under the two environmental light treatments differed in spectral reflectance, and adults transferred to the third environmental light treatment differed in spectral reflectance from their counterparts reared under the two original treatments. These results demonstrate that environmental light plays a large role in shaping signal reception in juveniles and signal production throughout ontogeny, suggesting that environmental light has the capacity to drive ecological speciation. / Thesis (Master, Biology) -- Queen's University, 2012-12-03 11:32:59.441

Aposematic signals advertise chemical defense or other forms of unprofitability to predators and may be parasitized by dishonest signallers through Batesian mimicry. Warning signals do not provide perfect avoidance, however, meaning many aposematic phenotypes evolve to balance between signal saliency and mitigating detection. For Batesian mimics the cost of a predator encounter should be greater, which begs the question of whether imperfect mimicry leads Batesian mimics to exhibit more muted signals than their models. I sought to test this hypothesis and other related hypotheses using the Ameerega-Allobates poison frog mimicry complex native to the Ecuadorian Amazonian rainforest. In Chapter 2 I found that, while many elements of the mimic’s signal were less salient than in the model, the mimic had higher detectability than the model. I also found that saliency discrepancies across colour patches produced variation in detectability across different body postures and viewing angles in both species. In Chapter 3 I turned my focus to how the balance between cryptic and salient signal elements changes across ontogeny, and how shifts in that balance may affect detectability. I found that both species undergo ontogenetic colour change, with the mimic improving in resemblance to the model as it developed and the model refining its aposematic signal as it grew. These colour changes impacted the crypsis efficacy of the mimic in that different colour stages had differential detectability. In Chapter 4 I tested for behavioural associations with the ontogenetic increase in mimetic fidelity in Al. zaparo. I found that colouration alone did not explain variation in behaviour, and that body size and environmental conditions impacted boldness and activity. / Dissertation / Doctor of Philosophy (PhD) / Antipredator colouration can take many different forms and can function according to different underlying strategies. Crypsis, also known as camouflage, operates by evading detection – effective crypsis means that predators don’t see the prey in the first place, increasing the prey’s survival. Using crypsis as an antipredator strategy means that a species should only occupy space where its colours blend in, however, and when hiding from predators it’s difficult to attend to other ecological needs like foraging, conquering and/or defending territory, or pursuing reproduction. These opportunity costs are thought to be reduced under aposematism, or ‘warning colouration’, where an animal evolves bright colouration that advertises some sort of secondary defense like toxic stings or secretions. Aposematic protection stems from standing out in the environment and being distinguishable from other prey, providing reduced predator attention across contexts such as foraging, reproduction, thermoregulation, or simple movement throughout the environment. These benefits can then be parasitized by a dishonest ‘mimic’ species which has no chemical defense but copies the warning signal of a ‘model’. Warning signal protection isn’t perfect, however, and most aposematic species still experience some form of predation threat. This means that there may be a limit to how conspicuous a signal an aposematic species is favoured to evolve. Accordingly, evidence shows that aposematic species incorporate both cryptic and aposematic elements into their colouration. The aim of this thesis is to examine how this balance is achieved by a poison frog and a non-toxic mimic, how this balance may change across development, and whether there are behavioural implications of changes in colour strategy. I found that both species have evolved a salient colour patch that they can flexibly expose or hide to modulate their detectability. I also found that the balance between crypsis and aposematism in the mimic and model shifts over time through developmental colour change. Lastly, I found that body size and environmental conditions affect behaviour in developing individuals of the mimic species.

The presented work investigates various theories about the significance of felid coat patterns. Most of the hypotheses are based on the theory of adaptive function of animal colouration. As regards felids, it is generally believed that the coat pattern has the function of aggressive resemblance. Early testimonies about cryptic properties of colouration of cats are summarized to provide the historical perspective of the problem. Other putative adaptive functions of patterns are investigated (intraspecific communication, thermoregulation) and close attention is paid to the option that the spotted coat of the leopard (Panthera pardus) serves as a cue for recognition from the perspective of prey. In the next stage, some of the hypotheses are tested by statistical means. The problem is simplified into search for association between a given category of a coat pattern (e.g. spots, stripes) and usual habitat of felid species (e.g. forest, grassland). Pagel's test for correlated changes is employed to account for phylogenetic relationships. In addition to broadly acknowledged hypotheses, the validity of proposition that juvenile coat patterns have the function of protective resemblance is tested. Finally, the problem of colouration of felids is linked to broader context of theoretical biology. Apart from prevailing...

In aposematism a prey species use bright colours, often combined with a black contrasting pattern, to signal unprofitability as prey to potential predators. Although there are several different hypotheses about the presence of these internally contrasting patterns, there is little experimental evidence of any beneficial effects. In this thesis I have used bird predators and artificial prey signals to investigate if the contrasting internal patterns in warning displays may have evolved to increase signal efficacy, especially regarding the speed of avoidance learning. In paper I the relative importance of colour and pattern in avoidance learning was studied. The conclusion was that birds primarily attend to colour, not pattern, when learning the discrimination, which was further supported by the results in paper II-IV, all suggesting a secondary role of patterns. In paper II I show that predators may to some degree use patterns for discrimination, if they convey important information about prey quality. The predators showed a hierarchical way of learning warning colour components, where colour is learned to a higher degree than pattern. In paper III I investigate if internal contrasting patterns promote avoidance learning by increasing conspicuousness as prey-to-background contrast does. The study did not support this idea, as the presence of internal black patterns did not improve avoidance learning on a colour matching background. In paper IV, however, I show that the presence of many internal colour boundaries resulted in faster avoidance learning on a multi-coloured background, and predator generalization favoured more internal boundaries, while there was no effect of pattern regularity. From these studies I conclude that internal pattern contrasts may function to increase the efficacy of the warning colour, its salience, and as a means for aposematic prey to be discriminated from harmful mimics. However, the major finding is the importance of colour over pattern. / <strong><em></em></strong><em></em><em></em>At  the time of the doctoral defence the following papers were unpublished and had a status as follows: Paper 2: Manuscript; Paper 4: Manuscript<strong><em> </em></strong>

Made available in DSpace on 2014-06-11T19:28:24Z (GMT). No. of bitstreams: 0 Previous issue date: 2006-02-24Bitstream added on 2014-06-13T20:18:07Z : No. of bitstreams: 1 komiyama_cm_me_botfmvz.pdf: 365903 bytes, checksum: 504da196f70e8cb733e0666e2460fef9 (MD5) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Universidade Estadual Paulista (UNESP) / Foram realizados dois ensaios, sendo que o Ensaio 1 teve por objetivo avaliar as características de qualidade da carne de frangos de corte de coloração pálida e comparar com a de coloração normal e, o Ensaio 2, avaliar as diferenças sensoriais destes tipos de carnes. Para o Ensaio 1, foram coletados 52 filés pálidos e normais selecionados na linha de abate baseado pela sua coloração. Foi realizada a mensuração do pH, temperatura, cor e valor R nos tempos de zero, 4 e 24 horas post-mortem. As amostras foram encaminhadas ao laboratório da FMVZ/UNESP, campus de Botucatu e após 24 horas post-mortem procedeu-se as demais análises de qualidade de carne em que foram avaliadas as características de perda por exsudação, capacidade de retenção (CRA) e absorção de água, perdas de peso por cozimento (PPC) e força de cisalhamento. Para o Ensaio 2, foram coletados 40 filés pálidos e normais de abatedouro comercial, e após 24 horas post-mortem procedeu-se a avaliação das características sensoriais. Para os filés de peitos de frangos de coloração pálida, a glicólise teve inicio com o valor de pH 6,86 e atingiu pH final 5,73 às 24 horas post-mortem enquanto que os filés de peitos de coloração normal apresentaram pH inicial de 6,80 e pH 24 horas post-mortem de 5,85. Houve diferença significativa (p 0,05) entre os filés pálidos e normal para os parâmetros de pH, valor L*, teor de vermelho, CRA, PPC e desnaturação protéica.

Like many other animals, butterflies are able to visually perceive the ultraviolet (UV) light; many species even have patterns on their wings which are visible in this part of the electromagnetic spectrum. Over the last forty years, it has been shown that these UV patterns play an important role in behaviour of many butterflies, especially in relation to sexual selection - they are involved in the process of recognising a suitable mate, and likely can signal some of the mate's qualities, such as its age, ability to handle stressful environmental factors, or efficiency in foraging. The patterns may also be used for taxonomical purposes. This dissertation thesis contains a comprehensive research into ultraviolet patterns of the Gonepteryx brimstones, with a primary focus on the issue of environmental influences in relation to the expression of these traits, on the patterns' potential role in sexual selection, or on their evolution. It has been successfully demonstrated that UV patterns of at least some Gonepteryx species are affected by the environment to a strong degree, significantly more than the traits not involved in sexual selection. On the whole, the conclusions made by submitted publications suggest that UV patterns play a role in the sexual selection of the chosen brimstones, though it is not clear...