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Avaliação das técnicas de criopreservação da pele e cartilagem auricular apical de Galea spixii (Wagler, 1831)
Get PDFA ordem Rodentia é constituída por uma variedade de espécies de pequeno a grande porte, e destes,
o Galea spixii é um representante de importante papel ecológico, econômico e científico. Buscando
contribuir para a conservação e conhecimento da espécie, bancos de tecidos somáticos representam
um passo significativo para o uso destas amostras como estratégias de conservação, sendo o
estabelecimento adequado dos protocolos de criopreservação tecidual a primeira etapa da formação
destes bancos. Portanto, o objetivo foi comparar duas técnicas de criopreservação tecidual
(vitrificação em superfície sólida vs. congelação lenta) na conservação de tecidos somáticos de G.
spixii. Para tanto, tecidos somáticos derivados de biópsias do pavilhão auricular apical de quatro G.
spixii machos e adultos pertencentes ao Centro de Multiplicação de Animais Silvestres
(CEMAS/UFERSA) foram coletados, e transportados ao laboratório em meio essencial mínimo
modificado por Dulbecco (DMEM) acrescido de 10% de soro fetal bovino (SFB) e 2% de solução de
antibióticosantimicótico. No laboratório, as amostras foram tricotomizadas, fragmentadas em 9,0
mm3 e distribuídas, aleatoriamente, entre os grupos: i) grupo controle (não criopreservado); ii)
vitrificação em superfície sólida (VSS) e iii) congelação lenta (CL). Para a CL, DMEM em associação
a 10% de dimetilsulfóxido (DMSO), 10% de SFB e sacarose (SAC; 0,2 M) foram empregados como
solução de criopreservação, enquanto para a VSS, 3,0 M de DMSO em associação a 3,0 M de
etilenoglicol (EG) e 0,25 M de SAC foram empregados. Tecidos somáticos foram avaliados quanto
às suas características morfológicas, morfométricas e proliferativas por técnicas histológicas. Além
disso, fragmentos foram submetidos ao cultivo primário, onde foi observada a viabilidade, atividade
proliferativa e metabólica, e níveis apoptóticos das células recuperadas. Os resultados foram
expressos como média ± erro padrão, considerando um animal/uma repetição. Os dados foram
analisados pelo software GraphPad, considerando P < 0,05. Para a análise da espessura da pele,
apenas a córnea sofreu alteração após a criopreservação por VSS (0,99 ± 0,31 μm), quando
comparada ao controle (0,81 ± 0,16 μm). Já na epiderme, derme e pele total, não foi verificado
diferença entre os grupos avaliados. Em relação à quantificação celular, a VSS (77 ± 17,8) se mostrou
similar ao controle (81 ± 18,9) quanto ao número de células da epiderme, enquanto a CL (22 ± 3,93)
apresentou um maior número de halos perinucleares quando comparado ao controle (19 ± 3,97). Na
derme, o número de fibroblastos mantevese similar entre os grupos experimentais, apesar da técnica
por CL ter apresentado um menor percentual de fibras colágenas. Após a avaliação da cartilagem, foi
observado que a VSS continha um maior número de condrócitos degenerados. Contudo, a CL
apresentou um menor número de condrócitos normais e lacunas preenchidas. Ainda, a técnica por CL
(1,65 ± 0,47) revelou uma maior área de AgNOR/célula quando comparado ao controle (1,07 ± 0,14)
e VSS (1,30 ± 0,31). Após o cultivo in vitro dos tecidos somáticos, não foi observada diferença após
a análise da viabilidade celular e atividade metabólica, demonstrando uma eficiência das técnicas
empregadas. Embora isso tenha ocorrido, as células pertencentes aos tecidos da VSS (34,1 h ± 2,9)
necessitaram de um maior tempo para duplicarse quando comparado ao controle (19,6 h ± 4,3) e CL
(24,4 h ± 2,9). Quanto aos níveis apoptóticos, foi observado que a CL continha um maior número de
células em apoptose tardia (22,3 ± 4,2) e necróticas (5,6 ± 2,2) quando comparado a técnica por VSS
(5,8 ± 1,6; 0,4 ± 0,3, respectivamente). Em síntese, os protocolos de criopreservação foram
eficientemente empregados em pele e cartilagem auricular de G. spixii. Contudo, considerando a
manutenção da arquitetura estrutural do tecido após a avaliação por histologia e cultivo in vitro, a
técnica por VSS se destaca em virtude da sua fácil execução, baixo custo e por oferecer a possibilidade
de aplicação em campo. Portanto, com essas informações, foi possível compreender algumas das
etapas envolvidas para a formação de bancos somáticos para o G. spixii.The order Rodentia is composed of a variety of species from small to large, and of these, the Galea
spixii is a representative of important ecological, economic, and scientific role. Seeking to contribute
to the conservation and knowledge of the species, somatic tissue banks represent a significant step
towards the use of these samples as conservation strategies, and the adequate establishment of tissue
cryopreservation protocols is the first step in the formation of these banks. Therefore, the aim was to
compare two techniques of tissue cryopreservation (solidsurface vitrification vs. slow freezing) in
the conservation of ear cartilage and skin of G. spixii. For this purpose, somatic tissues derived from
ear apical skin biopsies of four adult male G. spixii belonging to the Center for Multiplication of Wild
Animals (CEMAS/UFERSA) were collected and transported to the laboratory in Dulbecco's modified
minimal essential medium (DMEM) plus 10% fetal bovine serum (FBS) and 2% antibiotic-
antimycotic solution. In the laboratory, the samples were trichotomized, fragmented in 9.0 mm3 and
randomly distributed among the groups: i) control group (not cryopreserved); ii) solidsurface
vitrification (SSV) and iii) slow freezing (SF). For SF, DMEM in association with 10% dimethyl
sulfoxide (DMSO), 10% FBS and sucrose (SUC; 0.2 M) were employed as cryopreservation solution,
while for SSV, 3.0 M DMSO in association with 3.0 M ethylene glycol (EG) and 0.25 M SUC were
employed. Somatic tissues were evaluated for their morphological, morphometric, and proliferative
characteristics by histological techniques. Moreover, fragments were subjected to primary culture,
where viability, proliferative and metabolic activity, and apoptotic levels were observed in the
recovered cell. The results were expressed as mean ± standard error, considering one animal/one
repetition. Finally, the data were analyzed by GraphPad software, considering P < 0.05. For the
analysis of skin thickness, only the cornea was altered after cryopreservation by SSV (0.99 ± 0.31
μm), when compared to the control (0.81 ± 0.16 μm). In the epidermis, dermis, and total skin, there
was no significant difference between the groups. Regarding cell quantification, the SSV (77 ± 17.8)
was similar to the control (81 ± 18.9) regarding the number of epidermal cells, while the SF (22 ±
3.93) showed a higher number of perinuclear halos when compared to the control (19 ± 3.97). In the
dermis, the number of fibroblasts remained similar between the experimental groups, although the SF
technique showed a lower percentage of collagen fibers. After cartilage evaluation, it was observed
that the SSV technique contained a higher number of degenerated chondrocytes. However, the SF
technique showed a lower number of normal chondrocytes and filled gaps. Also, the SF technique
(1.65 ± 0.47) revealed a larger AgNOR/cell area when compared to control (1.07 ± 0.14) and SSV
(1.30 ± 0.31). After in vitro culture of the somatic tissues, no significant difference was observed after
analysis of cell viability and metabolic activity, demonstrating an efficiency of the techniques
employed. Although this occurred, cells belonging to SSV tissues (34.1 h ± 2.9) required a longer
time to duplicate when compared to control (19.6 h ± 4.3) and SF (24.4 h ± 2.9). Finally, on the
apoptotic levels, it was observed that the SF technique contained a higher number of cells in late
apoptosis (22.3 ± 4.2) and necrotic (5.6 ± 2.2) when compared to the SSV technique (5.8 ± 1.6; 0.4 ±
0.3, respectively). In summary, the cryopreservation protocols were efficiently employed in ear
cartilage and skin of G. spixii. However, considering the maintenance of the structural architecture of
the tissue after evaluation by histology and in vitro culture, the SSV technique stands out due to its
easy execution, low cost and for offering the possibility of application in the field. Therefore, with
this information, it was possible to understand some of the steps involved in the formation of somatic
banks for G. spixii.68 f
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
Author Under Sail The Imagination of Jack London, 1893-1902
No full textIn Author Under Sail, Jay Williams offers the first complete literary biography of Jack London as a professional writer engaged in the labor of writing. It examines the authorial imagination in London's work, the use of imagination in both his fiction and nonfiction, and the ways he defined imagination in the creative process in his business dealings with his publishers, editors, and agents. In this first volume of a two-volume biography, Williams traverses the years 1893 to 1902, from London's "Story of a Typhoon" to The People of the Abyss. The Jack London who emerges in the pages of Author Under Sail is a writer whose partnership with publishers, most notably his productive alliance with George Brett of Macmillan, was one of the most formative in American literary history. London pioneered many author models during the heyday of realism and naturalism, blurring the boundaries of these popular genres by focusing on absorption and theatricality and the representation of the seen and unseen. London created an impassioned, sincere, and extremely personal realism unlike that of other American writers of the time. Author Under Sail is a literary tour de force that reveals the full range of London as writer, creative citizen, and entrepreneur at the same time it sheds light on the maverick side of machine-age literature.Intro -- Title Page -- Copyright Page -- Dedication -- Contents -- Acknowledgments -- Introduction -- 1. Spirit Truth -- 2. From Absorption to Theatricality and Back Again -- 3. "I Will Build a New Present" -- 4. Sons as Authors -- 5. Fathers as Publishers -- 6. The Daughter as Author -- 7. Lovers as Authors -- 8. At Sea with the Family -- 9. Yellow News, Yellow Stories -- 10. The Return Home -- Notes -- Bibliography -- Index -- About Jay WilliamsIn Author Under Sail, Jay Williams offers the first complete literary biography of Jack London as a professional writer engaged in the labor of writing. It examines the authorial imagination in London's work, the use of imagination in both his fiction and nonfiction, and the ways he defined imagination in the creative process in his business dealings with his publishers, editors, and agents. In this first volume of a two-volume biography, Williams traverses the years 1893 to 1902, from London's "Story of a Typhoon" to The People of the Abyss. The Jack London who emerges in the pages of Author Under Sail is a writer whose partnership with publishers, most notably his productive alliance with George Brett of Macmillan, was one of the most formative in American literary history. London pioneered many author models during the heyday of realism and naturalism, blurring the boundaries of these popular genres by focusing on absorption and theatricality and the representation of the seen and unseen. London created an impassioned, sincere, and extremely personal realism unlike that of other American writers of the time. Author Under Sail is a literary tour de force that reveals the full range of London as writer, creative citizen, and entrepreneur at the same time it sheds light on the maverick side of machine-age literature.Description based on publisher supplied metadata and other sources.Electronic reproduction. Ann Arbor, Michigan : ProQuest Ebook Central, YYYY. Available via World Wide Web. Access may be limited to ProQuest Ebook Central affiliated libraries
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