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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.
471

Relação entre funções cognitivas e perdas adquiridas na visão de cores de pacientes com esclerose múltipla tipo remitente recorrente / Relationship between cognitive functions and acquired color vision loss in patients with relapsing-remitting type of multiple sclerosis

Rosaní Aparecida Antunes Teixeira 12 September 2012 (has links)
A Esclerose Múltipla (EM) é uma doença inflamatória autoimune caracterizada por desmielinização e degeneração do sistema nervoso central (SNC) duas a três vezes mais frequente em mulheres. A etiologia da EM é dividida em dois subtipos principais: o tipo remitente-recorrente (EMRR) mais comum, caracterizado por dois ou mais episódios de agravamento dos sintomas que envolvem diferentes locais do SNC, separados por pelo menos 1 mês e remisão dos sintomas e o tipo progressivo é a forma menos comum, caracterizada por um contínuo agravamento dos sintomas desde o início geralmente sem recaídas claras ou remissões. A presente pesquisa teve por objetivo avaliar o comprometimento da visão de cores e de sua relação com perdas de atenção, memória visual imediata, memória visual tardia, memória operacional e funções executivas dos portadores de esclerose múltipla tipo remitente recorrente. Método: participaram 41 pacientes com esclerose múltipla de idades entre 20 e 58 anos (35,4±12,2) e 37 controles com idade (34,7±12,1) e escolaridade semelhante. A discriminação de cores foi avaliada com o Cambridge Colour Test (CCT) e a avaliação de funções neuropsicológicas foram utilizados subtestes da bateria Cambridge Neuropsychological Testing Automated Battery (CANTAB) - Pattern Recognition Memory, Spatial Span, Spatial Recognition Memory, Information Sampling Task, Stop Signal Task e Rapid Information Processing; Escalas de Depressão e Ansiedade de Beck e Escala de Determinação Funcional da Qualidade de vida (DEFU). Resultados: A visão de cores está prejudicada de forma difusa em 24% dos pacientes com esclerose múltipla, tanto em pacientes com histórico de neurite óptica quando em pacientes que não tiveram neurite óptica. Na parte cognitiva, os pacientes demonstraram lentidão em executar as tarefas, comprometimento na atenção, na memória visual de curto e longo prazo, na memória operacional, na memória visuoespacial, além de lentidão no processamento de informações. Há uma relação entre alterações na visão de cores e alterações de memória visual somente em testes em que os estímulos são complexos e com inúmeros detalhes / Multiple sclerosis (MS) is an autoimmune inflammatory disease characterized by demyelination and central nervous system (CNS) degeneration. It is two times more frequent in women. It can be presented in two subtypes: the relapsing-remitting (RR), most common type, characterized by two or more episodes of focal disorders in different sites of the CNS, and remission of the symptoms; and the progressive subtype, less common, characterized by a continuous worsening of the symptoms, since the beginning, usually with no remissions. The present research evaluated color vision impairment and its relationship to attention loss, short-term memory, long-term memory, working memory and executive function in patients with the relapsing-remitting MS type. Methods: 41 patients with multiple sclerosis (20 to 58 years, 35.4 ± 12.2 in average) and 37 controls matched to age (34.7 ± 12.1 in average) and years of education participated of the study. Color vision was tested using the Cambridge Colour Test (CCT) and the neuropsychological assessment was performed using tests of the Cambridge Neuropsychological Testing Automated Battery (CANTAB) - Pattern Recognition Memory, Spatial Span, Spatial Recognition Memory, Information Sampling Task, Stop Signal Task, Rapid Information Processing the Beck Depression and Anxiety Inventories and the Functional Assessment of Multiple Sclerosis quality of life instrument. Results: Color vision was diffusely impaired in 24% of the MS patients, with or with no history of optic neuritis. Patients also showed a delay during the tasks execution, impairment in attention, short and long-term visual memory and working memory, and slowness in the information processing. There was a relationship between color vision loss and visual memory impairment, but only in tests with complex and highly detailed stimuli
472

Shades of Meaning :A Semiotic Approach to the Use of Polychromy in Egyptian Hieroglyphic Inscriptions

Nunn, David 09 February 2018 (has links)
Abstract:Uniquely amongst the earliest writing systems, the Egyptian hieroglyphic script was sometimes enhanced by colouring the signs. This was not done in an arbitrary fashion, but was conventional, with each colour used in a conscious attempt either at materialism, naturalism, semi-naturalism or as a metaphor. This study aims to shed some light on the processes involved in writing in colour. The methodology, theory, analysis and extended commentary are to be found in Volume 1.The study shows that a polychrome canon was in use, in a remarkably coherent and stable fashion, during some two thousand five hundred years, from the Old Kingdom right through to the Ptolemaic period. A palaeography, showing the best examples of each hieroglyph together with a brief commentary, forms the whole of Volume 2. These exemplars are taken from a database of polychrome hieroglyphs: a collection of over three thousand six hundred signs extracted from fifty-two monumental inscriptions. They cover 67% of all the hieroglyphs found in Gardiner’s sign list. Those signs in the collection that possess coloured images can all be found in Volume 3. The palaeography is intended to be a practical tool, as is the application created in order to facilitate the navigation, consultation and update of the database.In the process of analysing this data, several commonly held ideas about colour symbolism and the identification of certain hieroglyphs were brought into question and rectified, where possible. However, many unanswered questions remain, leaving the door open to further fascinating research. / Doctorat en Langues, lettres et traductologie / info:eu-repo/semantics/nonPublished
473

Aplikační aspekty textilních zátěrů s termochromními pigmenty / The application aspects of thermochromic textile coating

Štaffová, Martina January 2018 (has links)
V diplomové práci je prezentovaná literární rešerše na téma termochromní pigmenty a jejich aplikace v polymerních matricích. Výzkum byl zaměřen na hlubší pochopení termochromního efektu v pigmentech na bázi molekulárních komplexů. Termochromní pigmenty byly aplikovány do polyuretanového textilního zátěru a bylo zjištěno optimální nastavení podmínek zátěru. Textilní zátěry byly podrobeny termickým zkouškám a zároveň byla pozorována jejich stálobarevnost.
474

Návrh měřicího pracoviště v LabView pro účely měření spektra a světelného toku / Design of measuring workspace in LabView for purpose of spectrum and luminous flux measurement

Sláma, Pavel January 2017 (has links)
This thesis deals with luminance parameters measurement and ways to accomplish this using LabView software. The first part focuses on luminance parameters measurable by spectroradiometer and their meaning. Following part introduces reader to hardware equipment that is used in the measurement. Third part contains description of LabView software and explains what is required to make a communication between equipment and PC work. Next part explains how the communication with peripherals was achieved. Following up is the part where it is described how programs controlling AC and DC power supplies work. In this part the user interface is described.
475

Goniochromatic Gradients : Dichroic Color, Thin-Film Optics and Artificial Light

Eggeling, Erik Axel January 2018 (has links)
This thesis is about the multicolored gradients seen when using certain dichroic color lters with artificial light. As of now, this phenomenon lacks a unambiguous descriptor, and “Goniochromatic Gradient” is proposed. With help of optical physics, the science of color vision and information about dichroic products, principles for the relationship between goniochromatic gradients and dichroic filters are formulated for anyone interested in exploring this visual phenomenon.
476

Dionysos på Årsta torg : färgfrågan i svensk efterkrigsarkitektur

Ferring, Mari January 2006 (has links)
The overall aim of the thesis is to discuss cultural significations and notions of colour in Swedish post-war architecture. More specifically, the purpose is to analyse the question of colour in architecture linked to the polychrome walls of Årsta Community Centre, including background, intentions, cultural context and debate. Årsta Community Centre, situated just south of Stockholm, was built in 1947-53. The buildings as well as the colourful paintings covering the walls facing the square were designed by architects and brothers Erik and Tore Ahlsén. Newspapers and journals showed a clear indignation concerning the colourful exterior walls. Why did the polychrome walls at Årsta raise so much attention and cause such criticism? And how are these reactions related to contemporary ideas of colour in architecture in general? The thesis is divided into six chapters. The introductory chapter is followed by a historical retrospect with examples of use and notions of colour in architecture, in order to present a prelude to post-war thoughts and design. This text leads up to two central concepts developed for this thesis: Structural and independent colour effect. The third chapter presents Årsta Community Centre with focus on the polychrome walls at Årsta square, analysing the role of the architects and the cultural and social environment in which they were interacting. Special attention is paid to the important inspiration provided by the thoughts of the Danish artist and writer Asger Jorn. The forth chapter deals with the critique of Årsta square as well as arguments in contemporary debates concerning colour in architecture (as for example in the Apollo and Dionysus-debate). Chapter five discusses the role of independent colour effect in art and architecture of the 1940´s and 50´s related to examples of contemporary ideas and use of history. The conclusions of the study are presented in the sixth chapter. It contains an interpretation of the polychrome space, mainly focusing on two themes: The first is the understanding of the square as a theatre, based on historical social and urban patterns. The second is the suggestion of a modernistic language of colour and architecture for common man that is universal and time-less, challenging established social and material hierarchies. The thesis finishes with an analysis and a summary point by point of the critique directed at the colours of Årsta Community Centre with main emphasis on the underlaying political motives. / <p>QC 20101112</p>
477

Multimedia Processing: Real-Time Colour Grading with JIT using the MLT Framework

Kolling, Pina January 2024 (has links)
The topic of this thesis project is multimedia processing, focusing on the user-sided adjustment of RGB values in video streaming using Just-In-Time (JIT) techniques and the Media Lovin’ Toolkit (MLT) framework. This is implemented in Codemill’s Accurate Player and using Web Real-Time Communication (WebRTC) as a data channel. Colour theory and RGB colour representation are discussed and technical details on the structure and usage of the MLT framework are provided. The first part of the research question aims to evaluate the feasibility of the real-time colour adjustment. This research question is answered positively by providing an implementation that can address real-world use cases. A comparison of different MLT filters is included, to select the most suitable filter for the RGB adjustment. The second part of the research question considers the comparison of video colour grading results with MLT filters that were applied on different platforms: The Accurate Player, the command line video editor Melt and the editing software KDEN Live. For this, frames of the different platforms were extracted and subtracted from each other to show differences in the colour saturations. The results reveal that the Accurate Player plays back the original video more accurately than the Melt framework. Additionally, the results lead to the assumption that KDEN Live is not using the same Melt filter as the Accurate Player to adjust the RGB values. Those significant differences in the compared frames show the complexity of the topic of colour adjustment and representation.
478

Ontogenetic environments and female mate choice in guppies, Poecilia reticulata

Macario, Alessandro January 2013 (has links)
Theoretical models of sexual selection assume that female mating preferences are fixed and variation found between individuals resulting solely from allelic variation at specific loci coding for sexual preferences. For the last decade, an increasing number of studies have demonstrated that individual phenotypic variation in preferences was common across a wide range of taxa and induced by the environmental context and the females’ condition. Further, developmental stages of life are crucial in the formation of behaviours in general and have proven to be determinant to learn sexual preferences in some species that dispense care for their young. However, very little studies have analysed how the early social and physical environments shape female mate choice in species that lack parental care. In this thesis, I used guppies (Poecilia reticulata), firstly, to investigate the influence of various aspects of the social environment provided by males during two ontogenetic phases. Secondly, I explored whether learned preferences in a foraging context during development could be transferred into a mating context. Considering the early social environment, I explored three distinctive features potentially displayed by males and that females might experience while growing. Females were reared with different values of a sexual trait not genetically preferred in the population (orange colour) and different values of a trait for which they had innate predisposition (total colour area). In both cases, females were exposed to the different treatments for the whole developmental period or for its later phase. My results indicated that females changed their sexual behaviours in response to both type of traits experienced, reversing sometimes their genetic preferences. Moreover, the timing of exposure seemed to be a key factor in the acquisition of preferences as females exposed only to the later part of development with different values of total colour didn’t rely anymore on colour patterns to discriminate among males. In a third body of experiment, I examined whether the overall phenotypic variance exhibited by males during whole development, independently of the values of a specific sexual cue, mediated female’s behaviours. In a context of high variance, female became choosier relatively to those experiencing less variance. As a response, males switched mating tactics and attempted more forced copulations. In its final part, my thesis searched for a link that might have arisen, owing to developmental conditions, between preferences using the same sensory modality in two behavioural contexts. Maturing females were given food that was associated to a certain colour and subsequently tested for both their coloured preference in a foraging and a sexual context. Although no foraging preference for the corresponding colour was detected, females that experienced a yellow stimulus preferred yellower males compared to females with other experiences. Taken together these results suggest that developmental conditions and especially the social environment play a pivotal role in the process of mate choice. Under some circumstances, learned mate preferences override genetically-based preferences highlighting the importance of non-genetic mechanisms. Accordingly, it is urgent to integrate in the study of sexual selection and reproductive isolation this dimension. In guppies, for instance, the effect of early social life might contribute to the maintenance of colour pattern polymorphism found in males.
479

Accessing Genetic Variation by Microarray Technology

Lindroos, Katarina January 2002 (has links)
Microarray technology is a promising approach for the simultaneous analysis of multiple single nucleotide polymorphisms (SNPs), which are the most abundant form of genetic variation. In this thesis enzyme-assisted microarray-based methods were developed to improve the accuracy and genotype discrimination power of the current methods for SNP genotyping. The improved technology was applied for analysing recessively inherited disease mutations, for Y-chromosomal SNPs in a population study, for an evolutionary analysis of SNPs in flycatchers and for multiplexed quantitative determination of SNP-allele frequencies in pooled DNA samples. A robust attachment chemistry for immobilising oligonucleotides on glass surface was established, based on an evaluation of eight covalent coupling methods. A four-colour fluorescence detection strategy, which enabled a multiplexed quantitative analysis for as little as 2% of a minority allele frequency in pooled samples was generated. Twenty-five Y-chromosomal SNPs were screened in a collection of 300 samples from five Finno-Ugric-speaking populations using minisequencing on microarrays. In these populations six distinct haplotypes were defined by the six SNPs that were polymorphic. Data from five microsatellite markers was combined with the SNP data, revealing shared Y-chromosomal haplotypes between the Finns and the Saami, indicating, in accordance with earlier data, at least two founding Y-chromosomal lineages in these populations. Database screening and subsequent validation of 125 potential SNPs in the highly repetitive type 1 interferon genes and genes coding for proteins in the interferon-related regulatory pathways revealed 25 informative SNPs in the Finnish and Swedish populations. These SNPs were included in a panel for microarray based genotyping that should find a variety of applications in genetic studies due to the important immunoregulatory functions of the IFN family. The significance of sex-chromosome evolution on speciation was investigated in two naturally hybridising flycatcher species (N=459) by analysing a panel of 20 SNPs using minisequencing on microarrays. A strong selection against gene flow across the species boundary of sex-linked genes was observed, as well as a sex-chromosomal influence on male plumage characteristics that have previously been shown to reinforce isolation in these birds. The results suggest a major role for sex-chromosome-mediated isolation of the two flycatcher species.
480

Interaction of water deficit, canopy modification and ripening : effect on the phenolic and colour composition of Shiraz grapes & subsequent wine

Van Noordwyk, Marelize 12 1900 (has links)
Thesis (MScAgric)--Stellenbosch University, 2012. / ENGLISH ABSTRACT: Phenolic compounds are important quality indicators of a red wine, as they can contribute to the colour of a young red wine, colour stability during ageing as well as astringency, bitterness, body and overall mouthfeel properties. Wine composition is commonly influenced by winemaking and viticultural practices. In South Africa it often happens that vines are excessively vigorous, resulting in canopies that are too dense, which in turn could have a negative effect on the quantity and quality of the grapes produced. Viticultural practices such as judicious canopy management and irrigation are designed to control vine vigour and yield, thus improving fruit ripening and colour development. Artificial shading and water deficit have been reported to have an influence on the sensory properties of red wine as well as on the flavonoid composition. These effects are dependent on a number of factors, however, including the season, cultivar, light intensity, and the extent and timing of water deficit. There is limited research on the possible interactive effects of grapevine water deficits and canopy manipulation on grape and wine flavonoid composition in Shiraz, as well as the relationships between berry and wine composition. We thus investigated the effect of canopy reduction in combination with water deficit on the phenolic and colour composition of Shiraz grapes at different levels of ripeness, and in their corresponding wines after alcoholic and malolactic fermentation as well as after six months’ ageing. This study found that it is possible to improve the phenolic composition of grapes and wine by shoot removal, and some of the tendencies in the wines were also observed after the ageing period. If the shoot removal is not performed at a very early stage, sunburn damage can occur and this will result in berries with a lower mass and volume at harvest due to excessive exposure without the berry having adapted to the imposed conditions. Harvesting at different ripeness levels also affected the chemical and phenolic composition of the grapes and resulting wines. The water deficit effect on most phenolic parameters measured in the grapes and wine was not as prominent as that of the canopy manipulation treatment. This study improved our understanding of how an improvement in the canopy microclimate of Shiraz could be reflected in the phenolic composition of wines, along with a potentially important effect of harvesting date. On this basis it may be possible to attain a specific wine style. Harvesting at a ripe stage, for example, could result in the production of wines with higher colour density and astringency, while unripe grapes could result in wines with higher levels of perceivable fresh berry attributes. In particular, canopy reduction could increase the astringency and body of wines made from grapes subjected to water deficit. / AFRIKAANSE OPSOMMING: Fenoliese verbindings is belangrike kwaliteitsparameters van rooiwyn, aangesien dit kan bydra tot die kleur van ‘n rooiwyn, kleurstabiliteit tydens veroudering sowel as frankheid, bitterigheid en mondgevoel. ‘n Wyn se fenoliese samestelling word algemeen bepaal deur wynmaak- en wingerdkundige praktyke. In Suid-Afrika gebeur dit gereeld dat wingerde uitermatig groeikragtig is, wat lei tot te digte lower wat sodoende ‘n negatiewe effek op kwantiteit en kwaliteit van die druiwe wat geproduseer word, het. Wingerdkundige praktyke soos oordeelkundige lowerbestuur en besproeiing is ontwerp om wingerdstokke se groeikrag en opbrengs te beheer, en sodoende vrugrypwording en kleurontwikkeling te verbeter. Kunsmatige beskaduwing en waterstres is gerapporteer om ‘n invloed te hê op die sensoriese eienskappe van rooiwyn sowel as op die flavonoïedsamestelling. Hierdie effekte is egter afhanklik van ‘n verskeidenheid faktore, insluitende die seisoen, kultivar, ligintensiteit en die mate en tyd van waterstres toegepas. Daar is beperkte navorsing op die moontlike interaktiewe effekte van waterstres en lowermanipulasie op die druif en wyn flavonoïedsamestelling in Shiraz, sowel as die verhoudings tussen druif en wyn samestelling. Ons het dus die effekte van lowerbestuur in kombinasie met waterstres op die fenoliese en kleursamestelling van Shiraz druiwe by verskillende rypheidsvlakke ondersoek, asook in hul ooreenstemmende wyne na alkoholieseen appelmelksuurfermentasie sowel as na ses maande veroudering. Hierdie studie het gevind dat dit moontlik is om die fenoliese samestelling van druiwe en wyn deur lootverwydering te verbeter, en sommige van die tendense is ook waargeneem in die wyn na die verouderingsperiode. Indien lootverwydering nie toegepas word by ‘n baie vroeë stadium nie, kan sonbrand voorkom en dit kan lei tot korrels met ‘n laer massa en volume by oes as gevolg van oormatige blootstelling sonder dat die korrel aangepas het by die spesifieke kondisies. Oes by verskillende rypheidsvlakke affekteer ook die chemiese en fenoliese samestelling van die druiwe en ooreenstemmende wyne. Die waterstreseffek op meeste van die fenoliese parameters gemeet in druiwe en wyn was nie so prominent soos dié van die lowermanipulasie behandeling nie. Hierdie studie het ons begrip verbeter van hoe ‘n verbetering van die lower mikroklimaat van Shiraz gereflekteer kan word op die fenoliese samestelling van die wyn, saam met ‘n potensiële belangrike effek van oesdatum. Op grond van hierdie basis is dit dus moontlik om ‘n spesifieke wynstyl te verkry. Oes by ‘n ryp stadium, byvoorbeeld, kan die produksie van wyn met ‘n hoër kleurdigtheid en frankheid tot gevolg hê, terwyl onryp druiwe wyne met hoër vlakke van waarneembare vars bessiekenmerke tot gevolg kan hê. Verlaging van lowerdigtheid kan veral die frankheid en mondgevoel van wyne gemaak van druiwe blootgestel aan waterstres, verbeter.

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