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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.
201

O hybridním původu Chenopodium album / On the Origin of Chenopodium album by Means of Hybridization

Kondrysová, Eva January 2015 (has links)
Diploma thesis deals with genetic variability and evolutionary relationships among selected species of the group Chenopodium album and is especially focused on the origin of hexaploid species C. album in the Czech Republic. The main aim of the study was detection of putative recent emergence of hexaploid C. album s. str. in mixed populations of diploid (C. ficifolium and C. suecicum) and tetraploid (C. strictum and C. striatiforme) species. To assess phylogenetical relationships I performed an analysis of nuclear microsatellite loci, that are suitable for detection parental lines within polyploid species. As long as microsatellite primers have been developed for studied group, therefore they had to be cross-amplified from closely related species C. quinoa. Three PCR multiplexes were assembled by cross-amplification of microsatellite primers. These PCR multiplexes were tested on representative sample sets to estimate genetic variability of individual microsatellite loci. A total of 911 individuals were analyzed from five localities from the Czech Republic. The results of analyses revealed (1) high interspecific differentiation, (2) gene flow among species of the same ploidy levels, (3) presence of hybrids among diploid species of C. ficifolium and C. suecium as well as among tetraploid species C. strictum...
202

Molekulární fylogeneze a evoluční trendy v rodě Hieracium (Asteraceae, Lactuceae) / Molecular phylogeny and evolutionary trends in Hieracium (Asteraceae, Lactuceae)

Krak, Karol January 2012 (has links)
The hawkweed subgenus Hieracium s. str. is notoriously known for its extreme morphological variability and variation in ploidy levels that is associated with differences in modes of reproduction. Extensive past hybridization is supposed for the subgenus, but recent hybridization was evidenced only in few cases. The subgenus attracts the attention of botanists already for more than a century. Therefore the species diversity is largely examined and the taxonomy of the subgenus is well elaborated, although several contradictory taxonomic concepts exist. However the relationships among the species are unknown and haven't been studied yet. The investigation of these relationships from a phylogenetic perspective using molecular approaches was the main aim of the presented thesis. Basic species (both diploid and polyploid), representing morphologically unique taxa, that are supposed to be the basic evolutionary units of the subgenus were studied. The sequences of two intergenic spacers of the cpDNA (trnT-trnL and trnV-ndhC) and the external transcribed spacer of the nuclear ribosomal DNA (nrDNA ETS) were analyzed. Moreover, three new low-copy nuclear markers with higher variability than nrDNA and cpDNA markers were developed and their suitability for phylogenetic studies in Hieracium s. str. was...
203

A comparative analysis of geometric morphometrics across two Pseudemys turtle species in east central Virginia

Dillard, Kristin C 01 January 2017 (has links)
The phylogeny of the turtle genus Pseudemys is poorly understood. In Virginia, many turtles have been found with indicator traits of both eastern river cooters (Pseudemys concinna concinna) and northern red bellied cooters (Pseudemys rubriventris). This study explores morphological evidence for hybridization between the two species across three riverine sites in east central Virginia. Museum voucher groups for each species were analyzed for relative shell height and plastron length. The shape of the plastral scutes and upper jaw were analyzed using landmark-based morphometric software. These metrics were compared with measurements taken from 188 field-caught Pseudemys specimens. Across phenotypic metrics, field specimens resembled northern red bellied cooters. Geometric morphometric analysis showed extreme variation. Thirteen field specimens exhibited indicator traits of both species. Because species boundaries do not appear to be well-resolved using accepted phenotypes and morphometrics, we suggest that additional research utilizing molecular methods and genetic analysis be conducted.
204

Potencial da madeira de clones do híbrido Eucalyptus grandis x Eucalyptus urophyla para a produção de lâminas e manufatura de painéis compensados. / Potential use of wood from Eucalyptus grandis x Eucalyptus urophylla hybrid clones for veneer and plywood production.

Almeida, Renato Rocha 09 May 2002 (has links)
O presente estudo teve como objetivo principal avaliar o potencial da madeira de dois clones do híbrido Eucalyptus grandis x Eucalyptus urophylla para a produção de lâminas e manufatura de painéis compensados. Foram coletadas 5 árvores para cada clone (I e II) e duas toras de cada árvore, sendo uma da base (A) e outra subseqüente (B), totalizando 20 toras. As toras após descascamento e aquecimento em água quente foram processadas em torno laminador gerando lâminas de 2,00 mm de espessura nominal. O rendimento médio do processo de laminação foi de 51,74% para as toras do clone I e de 56,81% para as toras do clone II. A qualidade das lâminas produzidas foi avaliada com base na Norma de Controle de Qualidade e Classificação de Compensados, da ABNT. O clone I gerou lâminas de melhor qualidade: 11,94 % na classe A; 32,84 % na B; 54,48 % na C e 0,75 % na classe D, enquanto que o clone II gerou: 1,20 % na classe A; 8,40 % na B; 67,47 % na C e 22,89 % na classe D. Foram manufaturados compensados de 5 camadas, com lâminas da classe C para as capas e o miolo, coladas com adesivo à base de uréia-formaldeído. Os fatores de tratamento empregados na manufatura foram: clone (I e II), gramatura de cola (320 e 360 g/m2) e tempo de prensagem (8 e 12 minutos). O delineamento experimental foi inteiramente casualizado com arranjo fatorial do tipo 2 x 2 x 2. A partir dos compensados manufaturados foram obtidos corpos de prova para avaliação das propriedades físicas - massa específica aparente, absorção superficial de água, absorção total de água, inchamento mais recuperação em espessura e recuperação em espessura, e avaliação das propriedades mecânicas - flexão estática paralela e perpendicular (MOR e MOE) e resistência da linha de colagem ao esforço do cisalhamento nas condições seca e úmida. A análise estatística dos resultados das propriedades físicas e mecânicas foi realizada através de uma análise de variância. Não houve interação significativa entre os fatores clone, gramatura de cola e tempo de prensagem, considerando todas as variáveis avaliadas. Foram detectadas diferenças significativas para o fator clone em relação às variáveis massa específica aparente (maior para o clone I), absorção superficial e total de água (menores para o clone I); resistência da linha de colagem ao esforço do cisalhamento - condição seca e flexão estática - MOR paralelo e perpendicular (maiores para o clone I). Para o fator gramatura de cola não houve diferença significativa entre os tratamentos para nenhuma das variáveis avaliadas. Houve diferença significativa para o fator tempo de prensagem em relação às variáveis absorção superficial de água (menor para o tempo de prensagem de 12 minutos), inchamento mais recuperação em espessura e recuperação em espessura (menores para o tempo de prensagem de 8 minutos). A conclusão do trabalho é que as madeiras de ambos clones do híbrido Eucalyptus grandis x Eucalyptus urophylla apresentam alto potencial para produção de lâminas e manufatura de compensados. / The main objective of this work was to evaluate the potencial of eucalyptus grandis x Eucalyptus urophylla hybrid clones wood for plywood and veneer production. Five (5) trees were collected for each clone (I and II) and 2 logs of each tree, being one from base (A) and other subsequent one (B), totaling 20 logs. The logs after debarked and heated in hot water were processed in rotary cutting lathe generating veneers of 2,00 mm nominal thickness. The peeling yield was evaluated and mean values were 51,74% from clone I logs and 56,81% from the II one. The veneer quality graded was conduced following Norma de Controle de Qualidade e Classificação de Compensados, Brazilians standards. The clone I generated veneers of better quality: 11,94% of grade A veneer; 32,84% of B; 54,48% of C and 0,75% of grade D veneer, while the clone II generated: 1,20% of grade A veneer; 8,40% of B; 67,47% of C and 22,89% of grade D veneer. 5 layers plywood was manufactured with grade C veneers. The plywood manufacture treatment factors were: clone (I and II), glue amount (320 and 360 g/m2) and press time (8 and 12 minutes). From manufacture plywood were obtained specimens to evaluate the physical properties - apparent specific mass, superficial absorption of water, total absorption of water, thickness swelling more thickness recovery and thickness recovery, and the mechanical properties - parallel and perpendicular static bending (MOR and MOE) and bonding line shear test in the dry and wet conditions. The result obtained during the physical and mechanical assessments of plywood were analyzed using a variance analysis, executed by SAS (Statistical Analysis System). There was not significant interaction among the factors clone, glue amount and press time, considering all the appraised variables. Significant differences were detected for factor clone in relation to the variables apparent specific mass (clone I higher than clone II), superficial and total absorption of water (clone I smaller than clone II); bonding line shear test (dry condition) and static bending - parallel and perpendicular MOR (clone I higher than clone II). To the factor glue amount there was not significant difference among the treatments for none of the appraised variables. There was significant difference for the factor press time in relation to the variables superficial absorption of water (12 minutes smaller than 8 minutes), thickness swelling more thickness recovery and thickness recovery (8 minutes smaller than 12 minutes). It's concluded that Eucalyptus grandis x Eucalyptus urophylla hybrid clones wood have a high potencial for phywood and veneer production.
205

A fotografia a partir de uma visão sistêmica / The photography from a systemic view.

Ramos, Matheus Mazini 23 March 2016 (has links)
O surgimento da fotografia como descoberta científica causou grande impacto no universo das imagens e de forma vertiginosa se alastrou para muitas áreas do conhecimento. Esse potencial adaptativo e elástico da imagem fotográfica impulsiona a mesma para um contexto no qual as relações entre diferentes sistemas fazem surgir uma nova estrutura com elementos constitutivos de ambos. Com o avanço tecnológico e a convergência das mídias, através dos ambientes digitais, esse processo se potencializa e a complexidade do sistema fotográfico aumenta de tal forma que, em muitos casos, exige uma leitura refinada na tentativa de identificar elementos específicos da composição de seu sistema. Identificar e traçar um panorama de tais processos evolutivos é a linha norteadora desta tese, para, com isso, construirmos um percurso visual a fim de desenhar, através de imagens apresentadas, essas relações sistêmicas formadoras de novas estruturas. / The emergence of photography as scientific discovery caused great impact in the world of images and steeply spread to many areas of knowledge. This adaptive and elastic potential of the photographic image drives it to a context in which relationships between different systems give rise to a new structure with constitutive elements of both. With advances in technology and the convergence of media, through the digital environments, this process is strengthened and the complexity of the photographic system increases in such a way that, in many cases, requires a refined reading in an attempt to identify specific elements of the composition of its system. Identify and give an overview of these evolutionary processes is the guiding line of this thesis, to, thereby, build a visual route in order to draw, through images shown, these systemic relations forming new structures.
206

Narrativas silenciosas: identidade e imigração na educação infantil / Silent narratives: identity and immigration in early childhood education

Santos, Priscila da Silva 05 October 2018 (has links)
Esta pesquisa se desenvolveu com o intuito de analisar como se dão os processos de hibridização identitária de crianças em contexto de imigração na Educação Infantil. Para tanto, a investigação tem como base o tripé conceitual narrativa/identidade/ infância. A partir desse tripé descrevem-se as interações de uma criança de origem boliviana com seus pares, com a pesquisadora e com as professoras, a fim de depreender como se constroem as narrativas sobre essa criança e também as negociações realizadas para que tais narrativas sejam afirmadas ou rejeitadas, tanto pelos que constituem a comunidade escolar, quanto pela própria criança imigrante. Diário de campo, fotografias, filmagens, entre outros materiais que se revelaram pertinentes à análise constituem o corpus da pesquisa. O trabalho estreita relações com a Sociologia da Infância, à medida que experimenta metodologias que tentam dar voz às crianças envolvidas na pesquisa. Os dados obtidos no interior da escola de educação infantil (narrativa do micronível) foram relacionados com a contextualização geopolítica que circunscreve a relação entre Brasil e Bolívia (narrativa do macronível), e também com documentos oficiais que orientam o currículo da Educação Infantil. A partir dos resultados obtidos, foi possível concluir que os processos de hibridização identitária de crianças em contexto de imigração se dão em três categorias de diferenciação: 1) Diferenciação horizontal (relativa às diferenças que as crianças estabelecem entre si, sendo tais diferenças muitas vezes pautadas pelos padrões presentes na sociedade, mas também pelos interesses particulares que regem as interações infantis); 2) Diferenciação hierárquica (diz respeito ao modo como são conferidos diferentes status à criança imigrante, a depender do imaginário que se tem a respeito de seu país de origem, no país em que se estabelece); e 3) Diferenciação diaspórica (a propósito do movimento impulsionado pelo sair de si em direção à diferença do outro, a fim de partilharmos as diásporas que incessantemente alimentam as constituições identitárias). / This research was developed with the purpose of analyzing how the processes of identity hybridization of children are in the context of immigration in Early Childhood. The research is based on the conceptual tripod: narrative,identity and childhood. This tripod describes the interactions of a child of Bolivian origin and his peers, the researcher and the teachers, in order to understand how these narratives about child are constructed and the negotiations carried out to affirm or reject them, considering the parties who constitute the school community and the immigrant child itself. field diary, photographs, filming, and other materials produced during the observation proved to be relevant to the analysis and constitute the corpus of the research. The work has to link closely with the Sociology of Childhood as it experiments methodologies that try to give voice to children involved in the research. The data obtained inside the school of children\'s education (micro-narrative) was linked to the geopolitical contextualization (macro-narrative) and also to official documents that guide the curriculum of Early Childhood Education. Based on the results drawn from the research, it was possible to conclude that the processes of identity hybridization of children in the context of immigration take place in three categories of differentiation: The first is \"Horizontal differentiation, which refers to the differences that children establish among themselves, in present patterns in society and a particular interests that govern children\'s interactions. The second is \"Hierarchical differentiation\", which refers to how different statuses are given to the immigrant child, depending on the imaginary one that society has made upon his country of origin, in the country in which it is established. The third is \"Diasporic differentiation\", which refers to the movement of \"moving from one\'s self\" towards the difference of the other in order to share the diasporas that incessantly feed the identity constitutions.
207

The study of TLX gene expression during murine embryogenesis by in situ hybridization.

January 1998 (has links)
by Lam, Sau Hing. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1998. / Includes bibliographical references (leaves 141-158). / Abstract also in Chinese. / Content / Acknowledgements / Abbreviation / Project Objectives / Abstract / Chapter Chapter One --- Introduction / Chapter 1.1 --- The definition of homeobox genes / Chapter 1.2 --- Homeobox genes as a transcription factor / Chapter 1.3 --- Homeobox in Drosophila / Chapter 1.3.1 --- The development of Drosophila / Chapter 1.3.2 --- Maternal genes / Chapter 1.3.3 --- Segmentation genes / Chapter 1.3.4 --- Homeobox genes / Chapter 1.4 --- Family of Hox genes in the mammalian system / Chapter 1.5 --- Some possible chemical mechanism in the cascade system of the Hox genes in the vertebrate / Chapter 1.6 --- Hox (Antp-Class homeobox gene) in mammal / Chapter 1.6.1 --- Labial Like homeobox genes / Chapter 1.6.2 --- Proboscipedia Like homeobox genes / Chapter 1.7 --- Divergent homeobox genes / Chapter 1.7.1 --- Paired (prd) Class / Chapter 1.7.2 --- Even-Skipped (Eve) Class / Chapter 1.7.3 --- Distal-less (Dll) Class / Chapter 1.7.4 --- Muscle-Specific Homeobox (Msx) Class / Chapter 1.8 --- Orphan homeobox gene / Chapter 1.8.1 --- The characteristic of Hox 11 sequence in human and mouse / Chapter 1.8.2 --- Novel homeobox genes related to hox 11 gene family / Chapter 1.8.3 --- The mechanism of HOX 11 inducing gene regulation and signal transduction pathways / Chapter 1.8.4 --- HOX 11 in human / Chapter 1.8.5 --- Hox11 in mouse / Chapter 1.8.6 --- Hox11 L1 in mouse / Chapter 1.9 --- Homeobox gene involved in haematopoiesis / Chapter 1.10 --- Some translocations of homeobox genes in blood lineage / Chapter 1.11 --- The development of mouse / Chapter 1.11.1 --- Early organogenesis / Chapter 1.11.2 --- Nervous system development / Chapter 1.11.3 --- Somite development / Chapter 1.11.4 --- Eye development / Chapter 1.11.5 --- Neural crest cell migration / Chapter 1.11.6 --- Branchial arches development / Chapter Chapter Two --- Materials and methods / Chapter 2.1 --- Mouse Embryos / Chapter 2.2 --- RNA extraction / Chapter 2.3 --- Large plasmid preparation / Chapter 2.4 --- The synthesis of cDNAs using Reverse Transcription / Polymerase Chain Reaction (RT-PCR) and ligation into Bluescript® II KS / Chapter 2.4.1 --- The synthesis of RT-PCR products / Chapter 2.4.2 --- The formation of blunt ends of cDNA / Chapter 2.4.3 --- The ligation of cDNA with plasmid vectors / Chapter 2.4.4 --- Transformation / Chapter 2.4.5 --- The miniprep plasmid purification / Chapter 2.5 --- T7 sequencing / Chapter 2.6 --- Double stranded DNA cycle sequencing of plasmid / Chapter 2.6.1 --- Gel electrophoresis / Chapter 2.7 --- Northern blot / Chapter 2.7.1 --- Preparation of Northern blot / Chapter 2.7.2 --- Hybridization of Northern blot / Chapter 2.8 --- DIG labeled probes in whole mount in situ hybridization / Chapter 2.8.1. --- Preparation of linear DNA to generate riboprobes / Chapter 2.8.2 --- Preparation of DIG labeled riboprobe / Chapter 2.8.3. --- Preparation of embryo powder / Chapter 2.8.4 --- Absorption of antibody / Chapter 2.8.5 --- Embryo preparation / Chapter 2.8.6 --- Embryos staining / Chapter 2.9 --- Sections from whole mount in situ hybridization / Chapter 2.10 --- The radiolabeled section in situ hybridization / Chapter 2.10.1 --- The preparation of paraffin wax block and sample sections / Chapter 2.10.2 --- Slide pretreatment / Chapter 2.10.3 --- Preparation of probe / Chapter 2.10.4 --- Hybridization / Chapter 2.10.5 --- Washing / Chapter 2.10.6 --- Emulsification and development / Chapter 2.11 --- DIG-label in situ hybridization of frozen / Chapter 2.12 --- H&E staining / Chapter Chapter Three --- Results and Discussion / Chapter 3.1 --- Synthesis of Tlx3 probes for use in the section and whole mount in situ hybridization / Chapter 3.1.1 --- Synthesis of the Tlx cDNA by RT-PCR method / Chapter 3.1.2 --- The Tlx3 genomic clone for detecting the developmental expression of Tlx3 by Northern Blot / Chapter 3.1.3 --- The characterization of Tlx3 cDNAs and the sonic hedgehog cDNA / Chapter 3.2 --- Section in situ hybridization using different probes / Chapter 3.2.1 --- Section in situ hybridization using the transcribed riboprobes of Pax2 cDNA / Chapter 3.2.2 --- The transcribed riboprobes of Tlx genomic clones were used to hybridize the section in situ hybridization / Chapter 3.2.3 --- The in situ hybridization of frozen sections of mouse embryos using the transcribed riboprobes from Tlx3 cDNA subclone / Chapter 3.3 --- Expression pattern of Tlx3 on whole mount embryos using both cDNA and genomic probes / Chapter 3.3.1 --- The expression of Tlx3 on whole mount in situ hybridization of the mouse embryos using the antisense probes from the Tlx3 genomic clone / Chapter 3.3.2 --- Whole mount in situ hybridization of mouse embryo using the transcribed riboprobes of Tlx3 cDNA / Chapter 3.3.3 --- The expression pattern of sonic hedgehog on embryos at 8.5 to9.5 dpc / Conclusion / Future prospective / Appendix / Reference / Acknowledgement
208

Inferência das tecnologias nas narrativas teatrais

Pozzetti, Gislaine Regina 28 September 2017 (has links)
Submitted by Filipe dos Santos (fsantos@pucsp.br) on 2017-10-27T12:27:00Z No. of bitstreams: 1 Gislaine Regina Pozzetti.pdf: 3145724 bytes, checksum: cfd8f3442af86e2283787b63fa0e6d1c (MD5) / Made available in DSpace on 2017-10-27T12:27:01Z (GMT). No. of bitstreams: 1 Gislaine Regina Pozzetti.pdf: 3145724 bytes, checksum: cfd8f3442af86e2283787b63fa0e6d1c (MD5) Previous issue date: 2017-09-28 / This work problematizes the inferences that the technologies have contributed to the theatrical constituents throughout the history culminating with the necessity of their reframing, from the digital technologies. The objective is to discuss the issues that involve the conditions of presence, creation, time, space and participation of the spectator in today's theatrical practices. For this, it is questioned, as a problem situation of this thesis, that technical, aesthetic and poetic resonances the digital technologies inferred in theatrical narratives in the 21st century. The discussion is developed with bibliographical and cartographic research as a method, which supports the guiding thread of the new arrangements, configurations, hybridizations and deterritorizations that in the human historical trajectory were organized to give feedback to theatrical practices. Case studies bring to light paradigm reconfigurations of theatrical constituencies, sacred from the Greeks, such as the spectator paradigm that contemplates, acts, and interacts; The actor paradigm that begins to act in differentiated qualities of presence; The paradigm of text dramaturgy, which begins to be constructed in co-authoring with the user; The representation space paradigm consisting of bits; The paradigm of time, in which the symmetry experienced in the action becomes uninterrupted, and finally, the paradigm for the scenic elements that, like the presence, inhabit and constitute now in physical environments, sometimes in the liquid environments, without losing Its ephemeral art feature / Este trabalho problematiza as inferências que as tecnologias aportaram às constituintes teatrais ao longo da história e que culminaram na necessidade de resignificação destas, a partir das tecnologias digitais. Tem-se como objetivo discutir as questões que envolvem as condicionantes de presença, de criação, de tempo, de espaço e de participação do espectador nas práticas teatrais da atualidade. Para tal, questiona-se, como situação problema desta tese, quais ressonâncias técnicas, estéticas e poéticas as tecnologias digitais inferem nas narrativas teatrais no século XXI. Desenvolve-se a discussão tendo como método as pesquisas bibliográfica e cartográfica, que apoiam o fio condutor dos novos arranjos, configurações, hibridizações e desterritorializações que na trajetória histórica o homem organizou para retroalimentar as práticas teatrais. Estudos de casos trazem à luz reconfigurações de paradigmas das constituintes teatrais, sacralizadas desde os gregos, tais como, o paradigma de espectador que contempla, age e interage; o paradigma de ator que passa a atuar em qualidades de presença diferenciadas; o paradigma da dramaturgia de texto, que passa a ser construída em coautoria com o usuário; o paradigma de espaço de representação constituído em bits; o paradigma de tempo, em que a simetria vivida na ação passa a ser ininterrupta e, finalmente, o paradigma para os elementos cênicos que, tal como a presença, habitam e se constituem ora em ambientes físicos, ora nos ambientes líquidos, sem contudo perder sua característica de arte do efêmero
209

Período mínimo para a aquisição do Tomato severe rugose virus (ToSRV) por Bemisia tabaci biótipo B em tomateiros e identificação de sítios de aquisição do vírus / Minimum time for the acquisition of Tomato severe rugose virus (ToSRV) by Bemisia tabaci biotype B in tomato plants and identification of virus acquiring sites

Toloy, Rodrigo Solci 21 September 2015 (has links)
O Brasil atualmente ocupa a nona posição entre os maiores produtores de tomate (Solanum lycopersicum L.) do mundo. O desenvolvimento das plantas e a produção dos tomateiros, no entanto, podem ser afetados por diversos problemas fitossanitários, entre os quais aqueles causados por vírus. Atualmente, entre as viroses que mais tem se destacado estão aquelas causadas por espécies dos gêneros Begomovirus, Crinivirus e Tospovirus. Entre os begomovirus, especial atenção tem sido dada ao Tomato severe rugose virus (ToSRV), pois tem sido a espécie prevalente na maioria das regiões produtoras de tomate no país. Esse begomovirus, que até o momento foi relatado somente no Brasil, é transmitido pelo aleirodídeo (\"mosca branca\") Bemisia tabaci biótipo B, numa relação persistente circulativa. 8Estudos da relação do ToSRV com esse aleirodídeo indicaram períodos mínimos de acesso à aquisição e inoculação de 5 minutos. Esse trabalho teve como objetivos: a) identificar o menor tempo de alimentação da B. tabaci biótipo B para a aquisição do ToSRV em tomateiros e b) identificar possíveis sítios de aquisição do ToSRV em tecido foliar de tomateiro via microscopia de luz de epifluorescência por hibridização in situ. Insetos livres de vírus foram confinados em folha de tomateiro infectado com o ToSRV durante 1, 3 e 5 minutos e 24 h (controle) para a aquisição do vírus. Parte dos insetos foi utilizada para a detecção do vírus no vetor, enquanto a outra parte foi usada em testes de transmissão do ToSRV para tomateiros. A detecção do vírus no inseto e nos tomateiros foi feita por PCR. B. tabaci biótipo B foi capaz de adquirir o ToSRV nos diferentes tempos de alimentação. Os insetos foram capazes de transmitir o vírus para tomateiros, com eficiência de 33% a 100%. Análises de cortes histológicos longitudinais na região das nervuras de folhas de tomateiro infectados com o ToSRV, em microscopia de luz de epifluorescência por hibridização in situ, revelaram vários pontos de fluorescência localizados nas células do parênquima do floema, incluindo as células companheiras e nas células da epiderme. Essa fluorescência não foi constatada em tecido sadio. A localização do ToSRV em células do parênquima foliar do tomateiro, associada ao conhecimento de que esse aleirodídeo efetua picadas de prova intracelulares, de curta duração, durante o processo de penetração intercelular do estilete, podem explicar a aquisição deste begomovirus durante curtíssimos períodos de alimentação. / Brazil currently ranks ninth position among the largest tomato (Solanum lycopersicum L.) producers in the world. Several diseases, including those caused by virus, however, can affect plant growth and yield of tomatoes. Currently, among the most important virus diseases are those caused by species of the Genus Begomovirus, Crinivirus and Tospovirus. Among the begomoviruses, especial attention has been given to Tomato severe rugose virus (ToSRV), because it has been the prevalent species in most of the tomato producing regions of the country. This begomovirus, which so far has only been reported in Brazil, is transmitted by the whitefly Bemisia tabaci biotype B, in a persistent circulative relationship. Studies on the virus-vector relationship indicated five minutes as the minimum period of access for virus acquisition and inoculation by the vector. This study aimed to: a) identify the shortest feeding period of B. tabaci biotype B for acquisition of ToSRV in tomato plants, and b) identify possible ToSRV acquisition sites in infected leaf tissue via epifluorescence light microscopy by in situ hybridization. Virus free insects were confined in tomato leaf infected with ToSRV during 1, 3 and 5 minutes and 24 hours (control) for virus acquisition. Part of the insects was used for virus detection in the vector, while the other part was used on ToSRV transmission tests for tomato plants. Virus detection in both, insect tomato plants, was carried out by PCR. B. tabaci biotype B was capable to acquire the ToSRV on the different feeding times. The insects were capable to transmit the virus to the tomato plants, with efficiency of 33% to 100%. Analysis of longitudinal histological cuts of ToSRV infected leaves, in epifluorescence light microscopy by in situ hybridization, revealed several fluorescence spots located in phloem parenchyma cells, including the companion and the epidermal cells. Fluorescence was not verified on healthy tissue. The location of ToSRV in parenchyma cells of tomato leaf, associated with the knowledge that this insect performs very short intracellular feeding probes, during the process of intercellular penetration of the stylet, may explain the acquisition of this begomovirus during very short feeding periods.
210

Zebrafish as a model to study genes associated with neurodevelopmental disorders

Gostić, Monika January 2018 (has links)
Dyslexia is a neurodevelopmental disorder that affects between 5% and 12% of school-aged children. Individuals with dyslexia have difficulties in learning to read despite normal IQ levels and adequate socio-economical and educational opportunities. Dyslexia has a strong genetic component, but only a few candidate genes have been characterized to date. The KIAA0319 gene is a strong dyslexia candidate found to be associated with dyslexia in independent studies. The KIAA0319 genetic variants associated with dyslexia reside in a regulatory region. Studies in rat suggested that this gene is required for neuronal migration during early cortex formation. The KIAA0319-like (KIAA0319L) is a KIAA0319 homolog in structure and has recently been shown to play a role in dyslexia. I used zebrafish as a model organism both to study the effects of non-coding variants and to characterise kiaa0319 gene function. I used Gateway Tol2 technology to study the role of regulatory sequences. While these experiments led to inconclusive results, they highlighted some of the challenges but also the feasibility of using zebrafish as model organism to study genetic associations. In parallel, I studied the kiaa0319 function with knockout and knockdown experiments. Additionally, I conducted a detailed gene expression analysis with different in situ hybridisation protocols showing kiaa0319 ubiquitous expression in the whole embryo before 12 hours post fertilisation, with later specification to the eyes, brain, otic vesicle and notochord. Additionally, I have tested for the expression of kiaa0319l and showed similar expression pattern to the kiaa0319, but with significantly lower expression of kiaa0319l in zebrafish notochord. My data show, for the first time, that kiaa0319 has stage-specific expression in the brain and notochord during zebrafish early development, suggesting kiaa0319 specific role in the development of these structures. These results are in line with recent mouse studies. With this project I support the idea of kiaa0319 role being extended beyond the brain function and propose a role for kiaa03019 in the visual system and in the notochord.

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