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O projeto Nova Luz e a renovação urbana na região da Luz: o espaço urbano como condição e produto da acumulação e como espaço de reprodução da vida; Project New Light and renewal in the region of Luz: the urban space as a condition and product accumulation and as an space of reproduction of life

Pereira, Aglaé Vaz
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 11/12/2009 PT
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Essa pesquisa tem como objetivo fundamental analisar o processo de produção e reprodução social do espaço urbano e como se processa o desenvolvimento da contradição entre apropriação/dominação do espaço urbano na metrópole São Paulo, em especial na Região da Luz, área central da cidade. Entender esse processo implica considerar, em sua diversidade, a realidade sócio-econômica, política e cultural vivenciada pelos habitantes, comerciantes e usuários da Região da Luz, que também traduz a dinâmica da sociedade capitalista contemporânea. No desenvolver da pesquisa foi necessário estabelecer uma mediação e esta se deu com a realização de vínculos de amizade com habitantes, usuários e comerciantes da área. A análise mostrou que na base do processo de produção e reprodução do espaço na metrópole São Paulo está a reprodução contraditória do espaço urbano. Enquanto Estado e iniciativa privada, de modo interligado e ou independente disputam o uso do espaço, transformando-o em instrumento de dominação, as pessoas de modo geral tendem a se apropriar do espaço para a sua reprodução da vida. Nesses momentos é possível a emergência das insurgências contra o concebido; o estabelecido pelas ações que normatizam o espaço. Dimensão relevante como ponto de partida para a compreensão dessa produção espacial foi a reflexão sobre o conceito de espaço elaborado ao longo da história e sua possibilidade de apropriação e de uso...

Modernização capitalista e reprodução social da classe trabalhadora na periferia de Salvador/BA: o Pero Vaz e as formas e práticas derivadas da escravidão; Capitalist modernization and social reproduction of the working class on the outskirts of Salvador, Bahia: Pero Vaz and the forms and practices derived from slavery

Araújo, James Amorim
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Tese de Doutorado Formato: application/pdf
Publicado em 25/10/2010 PT
Relevância na Pesquisa
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Esta tese se propôs a pesquisar a reprodução social da classe trabalhadora na periferia da metrópole soteropolitana. O objetivo era compreender, no bojo do processo de modernização capitalista, o relacionamento entre as formas sociais de reprodução com as práticas da classe trabalhadora a partir de duas dimensões específicas: a do habitar e a do trabalho. Para tanto, buscamos dialogar com duas abordagens teóricas: a marxista de Henri Léfèbvre e a da resistência de Michel de Certeau. Este trabalho se compõe de cinco capítulos, além da introdução e considerações finais. No primeiro apresentamos nosso referencial teórico-metodológico. No segundo e terceiro capítulos são descritas as formas e práticas de reprodução da classe trabalhadora, respectivamente, nos níveis espaciais da cidade e do bairro. O quarto capítulo é o dedicado à análise formal do objeto. Enquanto no quinto a análise é de caráter dialético. Concluímos que parte significativa da reprodução da classe trabalhadora na periferia ocorre através de formas e práticas derivadas da escravidão, porque é uma condição necessária e contraditória da modernização capitalista típica em nossa formação social.; This thesis set out to investigate the social reproduction of working class in the outskirts of the city of Salvador. The goal was to understand in the middle of the process of capitalist modernization...

O campesinato no Vale do Jequitinhonha: da sua formação no processo de imposição do trabalho à crise da (sua) reprodução capitalista; The peasantry on the Jequitinhonha Valley: from its formation by the labor imposition process to the crisis of (its) capitalistic reproduction

Leite, Ana Carolina Gonçalves
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Tese de Doutorado Formato: application/pdf
Publicado em 02/03/2015 PT
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Nesse trabalho, abordamos as condições de reprodução do campesinato no Vale do Jequitinhonha mineiro, da sua formação até os dias atuais, tomando-as como momento da territorialização do capital e da mobilização do trabalho, observadas sempre nas transformações que sofreram no curso contraditório do processo de modernização. Investigamos a formação regional do campesinato no bojo da transição do escravismo colonial para o trabalho livre, relação engendrada como desdobramento da mineração ocorrida em muitos afluentes da bacia do rio Jequitinhonha e do estabelecimento e da expansão das fazendas pecuárias no que outrora fora considerado "sertão". Analisamos também a forma de reprodução desse campesinato, tomando-a como uma relação social de produção na qual se assentou a reprodução do capital, quando a mesma ainda não podia prescindir do domínio fundiário e recurso ao exercício da violência por parte daqueles que personificavam o capital e da produção direta dos meios de vida por parte daqueles que personificavam o trabalho. Apresentamos ainda a acumulação das condições para o rompimento daquela relação social de produção como resultado central da própria territorialização do capital responsável por engendrá-la...

Sexual and asexual reproduction in Didemnum rodriguesi (Ascidiacea, Didemnidae)

Ritzmann,Nicole F.; Rocha,Rosana M. da; Roper,James J.
Fonte: Fundação Zoobotânica do Rio Grande do Sul Publicador: Fundação Zoobotânica do Rio Grande do Sul
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/03/2009 EN
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Sexual and asexual reproduction and associated population dynamics were investigated in the colonial ascidian Didemnum rodriguesi Rocha & Monniot, 1993 (Didemnidae) in southern Brazil. Investment in sexual (production of new individuals) and asexual (colony growth) reproduction was compared between seasons. Permanently marked quadrats were repeatedly photographed to measure changes in colonies. Eggs and larvae were counted monthly in collected colonies. This species alternates seasonally between sexual (summer) and asexual (winter) reproduction. In summer, colonies were smaller, brooded eggs and larvae and recruitment rates were greater, while in winter, colony size was larger and eggs and larvae were absent. There is a relationship between fecundity and colony area. Fragmentation and fusion of colonies were similar in summer and winter, as well as mortality. In conclusion, D. rodriguesi has a lifecycle usual for high latitude ascidians with a limited time length for sexual reproduction and alternate investment in sexual and asexual reproduction along the year.

Body size and clonality consequences for sexual reproduction in a perennial herb of Brazilian rupestrian grasslands

Demetrio,GR; Coelho,FF; Barbosa,MEA
Fonte: Instituto Internacional de Ecologia Publicador: Instituto Internacional de Ecologia
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/08/2014 EN
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Body size is one of the most important factors regarding herbaceous perennial plants life-histories, and several fitness components of these organisms are related to size. Clonal plants show distinct kinds of reproduction and can develop offspring by sexual or asexual ways. We aimed to understand how body size affects Comanthera nivea (Eriocaulaceae) sexual reproduction and to verify how clonal growth is related to flower head production in this species. We sampled 600 rosettes in rupestrian grasslands and performed linear regression analysis between body size and number of produced flower heads. We also compared the flower head production between isolated rosettes and rosettes within clones. Our results showed that body size was significantly related, but explained only a small part of flower head production. The flower head production was higher in rosettes within clones than in isolated ones. The clones presented a rosette or a small group of rosettes that concentrated the sexual reproduction. Clonality was positively associated with sexual reproduction. Clonality can represent an important way of allowing the persistence of plants by sexual reproduction in markedly seasonal stressful environments. The cases of clonality enhancing the sexual reproduction must be considered and put in focus on reproductive biology research.

The influence of xenobiotics in river sediment on the reproduction and survival of Daphnia magna, 1820, Straus

Gonçalves,Silvana Pereira; Lucheta,Fabiane; Souza,Viviane Kelin de; Terra,Nara Regina
Fonte: Associação Brasileira de Limnologia Publicador: Associação Brasileira de Limnologia
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/06/2012 EN
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AIM: The Taquari River, a tributary of Guaíba Lake, is a major economic and environmental source for Rio Grande do Sul, a state located in the far south of Brazil; METHODS: This study evaluated the interference of sediment from this river in the reproduction and survival of 320 microcrustaceans (80 organisms per site) of the Daphnia magna species. Four sites between the middle course and the river mouth were monitored using eight samples from each site, between June/06 and April/10. Mortality higher than 20% suggested the acute action of the sample on the daphniids, while low reproduction indicated the presence of chronic toxicity. Sometimes an effect on survival was noted, but the number of individuals generated was always low. Semi-static chronic assays (21 day) were developed in 50 mL beakers using sediment and M4 culture medium at a ratio of 1:4 (v:v). Each beakers received a microcrustacean born from lots presenting LC50-24 hours = 0.98 mg K2Cr2O7 ± 0.04 mg totaling ten replicas per sample. The assays were developed under controlled light (16 hours light/day) and temperature (20 ºC ± 2 ºC) conditions; RESULTS: Duncan test showed a variation in reproduction (p < 0.05) with the presence of chronic toxicity. There was less reproductive activity in 91% of the samples...

Reproduction et échanges génétiques horizontaux chez les champignons mycorhiziens à arbuscules

Marleau, Julie
Fonte: Université de Montréal Publicador: Université de Montréal
Tipo: Thèse ou Mémoire numérique / Electronic Thesis or Dissertation
FR
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Les champignons mycorhiziens à arbuscules (CMA) ont une structure génétique très particulière et certains aspects de leur génétique sont encore incompris et peu documentés. Les CMA se reproduisent par voie asexuée à l’aide de spores multinucléées. Dans cette étude, j’ai cherché à comprendre les mécanismes de l’hérédité génétique des noyaux par la voie de la reproduction asexuée chez les CMA. La première étape était de déterminer le contenu en noyaux des spores matures, ainsi que celui des spores en formation. Des analyses statistiques ont été utilisées pour vérifier le type de relation entre le nombre de noyaux et le diamètre des spores. Quatre espèces du genre Glomus ont été observées au microscope confocal. Les résultats démontrent une hétérogénéité entre les spores dans leur contenu en noyau pour un même diamètre en plus d’une relation positive entre le nombre de noyau et le diamètre de la spore. Afin de vérifier le contenu en noyaux dans les phases extraracinaires, trois différentes structures du mycélium ont été observées au microscope confocal. Aucune structure n’a été retrouvée avec un seul noyau, ce qui permet de conclure que les CMA ne possèdent vraisemblablement pas de stade uninucléé dans leurs phases extraracinaires. Pour étudier l’hérédité des noyaux...

Sexual reproduction is the default mode in apomictic Hieracium subgenus Pilosella, in which two dominant loci function to enable apomixis

Koltunow, A.M.G.; Johnson, S.D.; Rodrigues, J.C.M.; Okada, T.; Hu, Y.; Tsuchiya, T.; Wilson, S.; Fletcher, P.; Ito, K.; Suzuki, G.; Mukai, Y.; Fehrer, J.; Bicknell, R.A.
Fonte: John Wiley & Sons Publicador: John Wiley & Sons
Tipo: Artigo de Revista Científica
Publicado em //2011 AA
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Asexual seed formation, or apomixis, in the Hieracium subgenus Pilosella is controlled by two dominant independent genetic loci, LOSS OF APOMEIOSIS (LOA) and LOSS OF PARTHENOGENESIS (LOP). We examined apomixis mutants that had lost function in one or both loci to establish their developmental roles during seed formation. In apomicts, sexual reproduction is initiated first. Somatic aposporous initial (AI) cells differentiate near meiotic cells, and the sexual pathway is terminated as AI cells undergo mitotic embryo sac formation. Seed initiation is fertilization-independent. Using a partially penetrant cytotoxic reporter to inhibit meioisis, we showed that developmental events leading to the completion of meiotic tetrad formation are required for AI cell formation. Sexual initiation may therefore stimulate activity of the LOA locus, which was found to be required for AI cell formation and subsequent suppression of the sexual pathway. AI cells undergo nuclear division to form embryo sacs, in which LOP functions gametophytically to stimulate fertilization-independent embryo and endosperm formation. Loss of function in either locus results in partial reversion to sexual reproduction, and loss of function in both loci results in total reversion to sexual reproduction. Therefore...

Adaptação transcultural e propriedades psicométricas do subteste Visual Reproduction (Reprodução Visual I e II) da Wechsler Memory Scale - Fourth Edition (WMS-IV), (Escalas de Memória de Wechsler) para uma população do Brasil; Transcultural Adaptation of the subtest Visual Reproduction I and II of the Wechsler Memory Scale - IV (WMS-IV) (Wechsler Memory Scale) to one culture from Brazil.

Spedo, Carina Tellaroli
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 27/04/2012 PT
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Instrumentos de avaliação da memória episódica não verbal são escassos. Além disto, consideramos a crescente necessidade de esforços para a adaptação transcultural de instrumentos de memória para nosso contexto. O subteste Visual Reproduction I e II (Reprodução Visual I e II) faz parte da Wechsler Memory Scale (WMS) e se trata de uma escala mundialmente utilizada e adaptada a diversas culturas, sendo considerada padrão ouro dentre as medidas de avaliação da memória. No presente estudo, utilizamos o subteste Reprodução Visual, da WMS na sua quarta edição (WMS-IV). O Reprodução Visual (RV) é subdividido em três domínios de investigação da memória visual (evocação imediata, evocação tardia e reconhecimento) e uma tarefa opcional para avaliação da percepção visual, habilidades construtivas e atenção aos detalhes (cópia). Além disto, o escore de cada um dos três domínios avaliados podem ser contrastados, de modo que se obtenham informações sobre a retenção, o quanto a memória é melhor ou pior do que as habilidades construtivas e, por último, o quão o sujeito evoca livremente ou precisa de pistas para evocar a informação aprendida. Esta versão da WMS-IV é uma revisão da WMS-III, cujos estudos resultaram em algumas alterações metodológicas e de conteúdo...

"The Messy Work": Parenting, Social Reproduction, and Neoliberal Restructuring in Jamaica

Gentles, AMALIA
Fonte: Quens University Publicador: Quens University
Tipo: Tese de Doutorado
EN; EN
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Examining the emergence and growing popularity of parenting programmes among states and international development agencies, this thesis explores the effectiveness of parenting interventions as a solution to high levels of social disorder, poverty, and violence that influence how poor families survive and carry out the “messy” work of social reproduction. Drawing on a case study of Jamaican parenting programmes and poor young women and men who participate in them, this thesis seeks to explore the relationship between these programmes and the neoliberal development strategies that the country has pursued for the last thirty years. Focusing specifically on the effects of liberalization on everyday practices of social reproduction among the urban poor, I argue that parenting programmes represent an institutional strategy aimed at shaping the behaviour of the poor, rather than addressing the structural causes that contribute to an ongoing crisis of social reproduction. Furthermore, I argue that parenting interventions reproduce racial and gender discourses and practices that target and pathologize poor, black Jamaicans as deficient and dysfunctional. Drawing on a critical policy approach, I contend that parenting cannot solve the larger anxieties created by the limited support given to spaces of social reproduction...

Toward a Virtue-Centred Ethics of Reproduction

Wayne, KATHERINE
Fonte: Quens University Publicador: Quens University
Tipo: Tese de Doutorado
EN; EN
Relevância na Pesquisa
36.702095%
When it comes to potential children, is to love them to leave them be (nonexistent)? I examine the possibility of virtuous reproduction, as well as some more basic theoretical issues surrounding the nature of moral goodness and obligation generally. Currently, there is a large body of literature in the field of reproductive ethics on questions of what considerations and practices ought to guide reproductive decision-making. The appropriate use of testing technologies to inform such decision-making, for instance, has been widely debated. Much smaller and less visible is the debate surrounding the prior question of whether reproduction itself is morally appropriate or desirable. I am particularly interested in how consequentialist strategies for including considerations of beneficence in reproductive decision-making have shaped moral approaches to reproduction. The principle of procreative beneficence (PPB), which mandates potential reproducers to select the best possible child, highlights the problematic nature of these strategies. The limited conceptual resources and problematic normative foundations of such strategies have stymied the development of a robust discussion on the ethics of reproduction itself. Other types of ethical approaches...

Effet d'un traitement intra-utérin de céphapirine sur les performances en reproduction des vaches laitières

Denis-Robichaud, José
Fonte: Université de Montréal Publicador: Université de Montréal
Tipo: Thèse ou Mémoire numérique / Electronic Thesis or Dissertation
FR
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La reproduction est un pilier majeur de la productivité des fermes laitières. Dans ce contexte, il est pertinent d’identifier à l’avance les animaux à risque d’avoir des performances en reproduction sous-optimales, surtout si un traitement efficace est disponible pour améliorer ces performances. Les endométrites clinique et subclinique sont des conditions définies selon leur impact sur les performances en reproduction subséquentes et donc, des outils très intéressants de surveillance de la santé utérine. Le premier objectif de cette étude était de déterminer simultanément des seuils diagnostiques pour les endométrites clinique (diagnostiquée par le Metricheck) et subclinique (diagnostiquée par la cytologie endométriale ou par l’estérase leucocytaire) selon leur impact sur les performances en reproduction à la première saillie. L’écoulement vaginal purulent a été identifié comme seuil pour l’endométrite clinique, alors que les seuils identifiés pour l’endométrite subclinique ont été un pourcentage de polymorphonucléaires de 6% à la cytologie et une « forte quantité de leucocytes » à l’estérase leucocytaire. Le second objectif de l’étude était d’évaluer l’effet d’un traitement intra-utérin de céphapirine sur les performances à la première saillie des animaux sains et atteints d’endométrite. Aucun effet du traitement n’a été observé chez les vaches saines ou atteintes d’endométrite clinique...

Téléphone, phonographe et radio : l'imaginaire sonore entre textualité et reproduction technique

Reinhardt, Marc A.
Fonte: Université de Montréal Publicador: Université de Montréal
Tipo: Thèse ou Mémoire numérique / Electronic Thesis or Dissertation
FR
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36.616707%
Ce mémoire décrit l’imaginaire sonore tel qu’il s’est transformé par l’apparition de dispositifs de reproduction (téléphone, phonographe et radio) à la fin du 19ème siècle et au début du 20ème siècle. Si ces appareils de reproduction sonore signalent un nouveau contexte socioculturel permettant la captation, la conservation et la transmission de manifestations sensibles, ils transforment également la manière de concevoir le son, ils modifient le statut de l’audition par rapport aux autres sens et reconfigurent un imaginaire qui traduit un rapport à soi, à autrui et au monde. Cette étude littéraire de la reproductibilité sonore propose une réflexion entre technologie et poétique en questionnant l’idée de communication. L’élément spécifique qui caractérise les appareils de reproduction sonore est un objet technique nommé «transducteur ». Je considère le transducteur à la fois comme métaphore et matérialité de médiation; conçu en termes de dispositif de transduction, ce concept permet une différente compréhension des pratiques sociales et de l’imaginaire constituant cet artefact culturel.; This thesis focuses on sound reproduction devices (telephone, phonograph and radio) that emerged in the late 19th and early 20th centuries. These aural technologies brought forth a new social and cultural context in which hearing became a distinctive characteristic of modern communication. But more importantly...

PMRD: a curated database for genes and mutants involved in plant male reproduction

Cui, X.; Wang, Q.; Yin, W.; Xu, H.; Wilson, Z.A.; Wei, C.; Pan, S.; Zhang, D.
Fonte: Biomed Central Publicador: Biomed Central
Tipo: Artigo de Revista Científica
Publicado em //2012 EN
Relevância na Pesquisa
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BACKGROUND: Male reproduction is an essential biological event in the plant life cycle separating the diploid sporophyte and haploid gametophyte generations, which involves expression of approximately 20,000 genes. The control of male reproduction is also of economic importance for plant breeding and hybrid seed production. With the advent of forward and reverse genetics and genomic technologies, a large number of male reproduction-related genes have been identified. Thus it is extremely challenging for individual researchers to systematically collect, and continually update, all the available information on genes and mutants related to plant male reproduction. The aim of this study is to manually curate such gene and mutant information and provide a web-accessible resource to facilitate the effective study of plant male reproduction. DESCRIPTION: Plant Male Reproduction Database (PMRD) is a comprehensive resource for browsing and retrieving knowledge on genes and mutants related to plant male reproduction. It is based upon literature and biological databases and includes 506 male sterile genes and 484 mutants with defects of male reproduction from a variety of plant species. Based on Gene Ontology (GO) annotations and literature, information relating to a further 3697 male reproduction related genes were systematically collected and included...

Communicating Reproduction

Hopwood, Nick; Jones, Peter Murray; Kassell, Lauren; Secord, Jim
Fonte: Johns Hopkins University Press Publicador: Johns Hopkins University Press
Tipo: Article; accepted version
EN
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This is the author accepted manuscript. The final version is available from Johns Hopkins University Press via http://dx.doi.org/10.1353/bhm.2015.0064; Communication should be central to histories of reproduction, because it has structured how people do and do not reproduce. Yet communication has been so pervasive, and so various, that it is often taken for granted and the historical specificities overlooked. Making communication a frame for histories of reproduction can draw a fragmented field together, including by putting the promotion of esoteric ideas on a par with other practical activities. Paying communication close attention can revitalize the history of reproduction over the long term by highlighting continuities as well as the complex connections between new technologies and new approaches. Themes such as the power of story-telling, the claiming and challenging of expertise, and relations between knowledge and ignorance, secrecy and propriety also invite further study.; This essay introduces a special issue that began in a conference on ?Communicating Reproduction? (http://www.hps.cam.ac.uk/medicine/communicating.html) held at the Department of History and Philosophy of Science, University of Cambridge in December 2011. This was linked to an exhibition on ?Books and Babies? at Cambridge University Library curated by Mary Fissell...

Unisexual Reproduction in Cryptococcus: Evolutionary Implications, Virulence and RNA Silencing

Feretzaki, Marianna
Fonte: Universidade Duke Publicador: Universidade Duke
Tipo: Dissertação
Publicado em //2013
Relevância na Pesquisa
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Sexual development enables microbial pathogens to purge deleterious mutations from the genome and drives genetic diversity in the population. Cryptococcus neoformans is a human fungal pathogen with a defined sexual cycle. Nutrient-limiting conditions and pheromones induce a dimorphic transition from unicellular yeast to multicellular hyphae and the production of infectious spores. C. neoformans has a defined a–α opposite sexual cycle (bisexual reproduction); however, >99% of clinical and environmental isolates are of the α mating type. Interestingly, α cells can undergo α–α unisexual reproduction, even involving genotypically identical cells. A central question is why would cells mate with themselves given that sex is costly and typically serves to admix pre-existing genetic diversity from genetically divergent parents? Sexual reproduction generates abundant spores that following inhalation, they penetrate deep into the alveoli of the lung, germinate, and establish a pulmonary infection growing as budding yeast. Therefore sex has been linked with virulence; however, hyphal development has been previously associated with reduced virulence and thus the roles of morphogenesis in virulence have not been extensively analyzed. To further understand the role of unisexual reproduction in C. neoformans we will investigate the evolutionary implications of α–α mating...

A study on the improvement of ROP newspaper color through modification of the reproductive curve to lighten the overall reproduction

Assoian, Ronald
Fonte: Rochester Instituto de Tecnologia Publicador: Rochester Instituto de Tecnologia
Tipo: Tese de Doutorado
EN_US
Relevância na Pesquisa
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Most run on paper offset newspapers have not shown the capability of producing color reproductions without having the prints subject to a darkening or a muddy look. This problem is basically caused by the absorbency of the newsprint. Since the newsprint is so absorbent, the ink can only be printed to a low solid ink density and coarse screens must be used so the dots do not fill-in. To eliminate this problem, it is believed that if the midtones are reduced on the gray scale during the separation process, and then the wanted colors' dot areas are restored to their normal values, a reduction in the unwanted colors will occur. This should produce a cleaner, less contaminated looking print. To test this theory, a control separation was made using a normal newsprint tone reproduction curve. Then, variations in the separation process were performed to both under and over correct for the amount of contamination in the reproductions. These separations were printed on a Solna four-color 25-inch press while manipulating this press's printing characteristics to make it similar to a Goss Metro, a widely used offset newspaper printing press. The reproductions were shown to 30 randomly selected newspaper observers who rated each printed separation on a scale from 1 (totally unsatisfactory) to 9 (most satisfactory). The results of this experimentation proved that newspaper observers preferred a print with a lightened overall reproduction from the normal newsprint reproduction curve while keeping the apparent visual saturation in the colored areas constant. This is based on the fact that the prints where the midtones were reduced by 10 percent and 5 percent were rated by the observers as being their first and second choices...

Evaluation and improvement of the workflow of digital imaging of fine art reproduction in museums

Jiang, Jun
Fonte: Rochester Instituto de Tecnologia Publicador: Rochester Instituto de Tecnologia
Tipo: Dissertação
EN_US
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Fine arts refer to a broad spectrum of art formats, ie~painting, calligraphy, photography, architecture, and so forth. Fine art reproductions are to create surrogates of the original artwork that are able to faithfully deliver the aesthetics and feelings of the original. Traditionally, reproductions of fine art are made in the form of catalogs, postcards or books by museums, libraries, archives, and so on (hereafter called museums for simplicity). With the widespread adoption of digital archiving in museums, more and more artwork is reproduced to be viewed on a display. For example, artwork collections are made available through museum websites and Google Art Project for art lovers to view on their own displays. In the thesis, we study the fine art reproduction of paintings in the form of soft copy viewed on displays by answering four questions: (1) what is the impact of the viewing condition and original on image quality evaluation? (2) can image quality be improved by avoiding visual editing in current workflows of fine art reproduction? (3) can lightweight spectral imaging be used for fine art reproduction? and (4) what is the performance of spectral reproductions compared with reproductions by current workflows? We started with evaluating the perceived image quality of fine art reproduction created by representative museums in the United States under controlled and uncontrolled environments with and without the presence of the original artwork. The experimental results suggest that the image quality is highly correlated with the color accuracy of the reproduction only when the original is present and the reproduction is evaluated on a characterized display. We then examined the workflows to create these reproductions...

Analysis of color errors and their sources in a commercial color reproduction process

Sakda Siriphan
Fonte: Rochester Instituto de Tecnologia Publicador: Rochester Instituto de Tecnologia
Tipo: Tese de Doutorado
EN_US
Relevância na Pesquisa
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To analyze color errors and their sources in the color reproduction process, the reproduction is visually evaluated and compared visually with the original scene color scales and also with the original transparency viewed on a variable brightness illuminator (D5000) with an opaque reflective white surround. Graphs (press plate curves, single color proofs and END of single color proofs) have been added to the Kodak tone-reproduction diagram (1960) to obtain more complete steps in the analysis of the tone-reproduction and the color balance. The GATF Evaluation Method of Ink Color is tested and the GARC colorimetric system, which is a modified Adam’s chromatic value system, is used to analyze colorimetric measurement. The slightly dark reproduction, the shift of the color balance to bluish cyan in the reproduction; the shift of hues, the magenta toward red, the cyan and the green toward blue; and the desaturation of the blue, the cyan and the yellow are discovered as errors in the reproduction. The possible improvements of these errors are discussed. The hope to combine the tone-reproduction analysis, the GATF Evaluation of Ink Color and the GARC colorimetric system into one system of analysis of the color errors is not fulfilled, because the mask percentages obtained from the Evaluation of Ink Color do not agree with that of the reproduction process and the hue error and grayness of the Evaluation of Ink Color do not correspond with the visual hue and the color saturation. However...

Relationship of Preferred Tone Reproduction to Picture Size

Miller, David
Fonte: Rochester Instituto de Tecnologia Publicador: Rochester Instituto de Tecnologia
Tipo: Tese de Doutorado
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A relationship between preferred tone reproduction and final picture size is suggested in many forms in the literature and in practical experience. This project uses photographic halftone prints varying in tone reproduction and produced at different sizes to investigate this relationship. The tone reproduction variations are introduced electronically using an RCA color scanner and a method of eigenvector analysis is used to reduce these tone reproductions down to their important components. The final set of prints consisting of ten tone reproductions, three reproduced sizes, and two sharpnesses are evaluated to determine their subjective quality in the judgement of a group of ten observers. These quality ratings are normalized and averaged and then mathematically correlated with an eigenvector representation of their tone reproduction. The preferred tone reproduction (producing maximum quality) may then be determined for each picture size. Due to large differences in quality rating from observer to observer and an incomplete selection of tone reproductions, no definite relationship was determined. Useful information was obtained on the use of the eigenvector method, the magnitude of quality variation as tone reproduction is changed...