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Caracterização dos polissacarídeos sulfatados das túnicas de diferentes espécies de ascídias e determinação da estrutura da fração f-1 de Styela plicata
No full textBV UNIFESP: Teses e dissertaçõe
Exploração do genoma de Phytomonas serpens
No full textO estudo de tripanosomatídeos de plantas teve início em 1909, quando foram
encontradas formas flageladas em látex, sendo depois encontradas em floema, frutas e
flores. Desde a refutada tentativa de Donovan de criar o gênero Phytomonas, temos
atualmente, várias espécies classificadas dentro do gênero Phytomonas, incluíndo
Phytomonas serpens, organismo alvo de nosso estudo. O ciclo de vida de P. serpens
compreende planta e inseto. A transmissão é feita do tomate para inseto, do inseto para
tomate. O vetor natural é o hemíptero Phthia picta (Hemiptera: Coriidae) que quando se
alimenta de tomates infectados, se torna infectado após 10 a 15 dias, apresentando
parasitos nas fezes, urina, tubo digestivo e glândulas salivares. Pouco se sabe sobre P.
serpens e o conhecimento é ainda mais escasso se levarmos em conta todos os
organismos dentro do gênero Phytomonas. O objetivo deste projeto é explorar o genoma
de P. serpens gerando e analisando seqüências de seu genoma, aumentando o
conhecimento deste organismo e comparando seu genoma com outros organismos. A
cepa 9T de P. serpens (CT–IOC-174) foi cultivada a 27oC em meio Schneiders ́insect
medium suplementado com 10% de soro fetal bovino. O DNA genômico foi extraído
por lise alcalina para a construção da biblioteca genômica. O DNA foi parcialmente
digerido com a enzima de restrição Sau3A. Os fragmentos de DNA com tamanhos entre
1-3 kb foram recuperados do gel de agarose e purificados. Os fragmentos de DNA
foram clonados no sítio BamHI do vetor de clonagem pUC18. A reação de
sequenciamento foi realizada na plataforma de sequenciamento ABI3730 – 48 capilar
PDTIS/FIOCRUZ e na plataforma MegaBase na UERJ. Todas as seqüências foram
armazenadas em banco de dados “open source” nos servidores Linux no Laboratório de
Biologia Molecular de Tripanosomatídeos e Flebotomíneos (DBBM/IOC/FIOCRUZ).
Foram seqüenciados 829 clones da biblioteca de DNA genômico obtendo-se um total de
379 seqüências GSS (Genomic Sequence Survey) de alta qualidade. Foram utilizadas
para a complementação deste estudo, as seqüências do projeto EST de P. serpens que
estavam disponíveis no GenBank. Os 221 clusters GSS e os 697 clusters de EST
(Expressed Sequence Tag) foram comparados com o programa de busca de similaridade
Blast a diferentes bancos de dados, utilizando como parâmetro evalue 10 -5, gerando 599
clusters com entradas positivas (Hits) e 303 clusters com nenhum hit, representando
possíveis genes espécie específicos. Os clusters foram anotados de acordo com sua
função quando comparados ao banco de dados Gene Ontology (GO) representando uma
análise inédita no genoma de P.serpens. Inferências filogenéticas e de similaridade com
o banco “Taxonomy” do NCBI foram realizados, usando inclusive seqüências do
genoma ambiental, para verificar se as mesmas pertencem a Kinetoplastida, o que não
se comprovou. As inferências filogenéticas realizadas com genes concatenados
mostraram que P. serpens é mais próximo de T. cruzi, enquanto que inferências com
genes individuais apontaram para L. major. Com base na literatura, inferimos que a
análise da árvore de genes concatenados é correta. Foram encontradas com o
GLIMMER 20 genes hipotéticos nas seqüências de GSS. Encontramos 22 cluters em
GSS que não foram encontrados anteriormente em EST, como por exemplo,
Piroglutamil-peptidase I, antígeno nuclear de proliferação celular (PCNA) e
Peptidase_M8.CnpqThe study of trypanosomatids of plants began in 1909, when flagellate forms
were found in latex from Euphorbiaceae, being later found in phloem, fruits/seeds and
flowers in a wide variety of plants species. Since the refuted attempt of Donovan to
create the genus Phytomonas, a great number of species were classified in the genus
Phytomonas, including Phytomonas serpens, the major organism of our study. The
described life cycle of P. serpens involves plant (tomato) and insect. The natural vector
is the Coreid bug, Phthia picta (Hemiptera: Coriidae), that becomes infected 10 a 15
days after feeding on infected tomatoes, presenting the parasite in excrements, urine,
digestive tube and salivary glands. Very little is known about these organisms and even
less is known about the genus Phytomonas. The goal of this project is to explore the P.
serpens genome by generating and analyzing sequences of its genome aiming to
increase the knowledge of this organism and to analyze comparatively with genomes of
other organisms. P. serpens infects tomatoes but we still have doubts about its
pathogenicity. A strain of P. serpens 9T (CT-IOC-174) was cultured at 27oC in
Schneiders ́insect medium supplemented with 10% heat-inactivated fetal bovine serum.
The DNA was extracted by alkaline lyses for the construction of a genomic library.
Genomic DNA was partially digested with the restriction enzyme Sau3A. DNA
fragments with an average size of 1.0-3.0 kb were recovered and purified from agarose
gel. DNA inserts were cloned into the BamHI restriction site of pUC18 cloning vector.
The sequencing reaction was made at the Sequencing Platform ABI3730 -
PDTIS/FIOCRUZ and MegaBase platform at UERJ. All the sequences were stored in
an open source database in the Linux server in the Laboratory of Molecular Biology of
Trypanosomatids and Phlebotomines (DBBM/IOC/FIOCRUZ). 829 clones of the P.
serpens genomic DNA library were sequenced obtaining a total of 379 high quality
sequences GSS (Genome Sequence Survey). Sequences from the EST (Expressed
Sequence Tag) project of P. serpens available at GenBank were used for the
complementation of this study. 221 GSS clusters and 697 EST clusters were compared
with different databases with the similarity search program Blast, using evalue 10 -5 as
default, obtaining 599 clusters with positive hits and 303 clusters without hit, indicating
possible species-specific genes. 357 clusters that were identified when compared with
Gene Ontology (GO) had their function classified, representing the first analysis of P.
serpens genome using GO. Phylogenetics and similarity studies with Taxonomy
database from NCBI were carried out confirming the position of P. serpens in relations
to the others trypanosomatids and disclosing similarity with T. cruzi genome. The
phylogenetic study included sequences of the enviromental genome, in order to verify if
these sequences belong to the Kinetoplastid, what was not proven to be true.
Phylogenetic studies using concatenated genes showed that P. serpens is
phylogenetically closer to T. cruzi, but studies with individuals genes pointed to L.
major. Based on literature, we infer that the analysis of the tree of concatenated genes is
correct. 20 hypothetical genes in the GSS sequences were found with the GLIMMER.
We found 22 clusters in GSS sequences that were not found in EST before, among
others, Pyroglutamil-peptidase I, proliferating cell nuclear antigen (PCNA) and
Peptidase_M8
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Get PDFWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Get PDFWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
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