1,721,004 research outputs found
Effect of the algal alkaloid caulerpin on neuropeptide Y (NPY) expression in the central nervous system (CNS) of Diplodus sargus
Full text linkRecent studies have suggested that Mediterranean indigenous fish species are affected by bioactive metabolites coming from marine invasive species via food web interactions. In particular, both physiological and behavioural changes in the white sea bream Diplodus sargus were related to caulerpin (CAU), a bisindolic alkaloid particularly abundant in the invasive alga Caulerpa cylindracea, on which the fish actively feed. Dietary administration of CAU decreased aggressiveness in D. sargus, suggesting an anxiolytic-like effect of CAU possibly mediated by endogenous anxiolytic agents. This hypothesis is supported here by the finding of a significant increase of NPY transcriptional expression in the brain of fish fed with CAU enriched food, shedding more light on the neural mechanisms behind the altered behaviour of D. sargus.Fundação para a Ciência e a Tecnologia - FCT; FEDERinfo:eu-repo/semantics/publishedVersio
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe 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
Full text link“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
Full text linkWe 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
Full text linkWe 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
Análise palinológica e mineralógica de solos portugueses e o seu potencial na prática forense
Full text linkOrientador : Frederico AlmadaO presente trabalho apresenta o estudo palinológico e mineralógico da camada superficial do solo, de dois Distritos de Portugal (Coimbra e Setúbal), com vista à determinação do potencial forense da utilização de amostras de solo, no que respeita à identificação do tipo de comunidade vegetal e material mineralógico da qual a amostra teve origem, que poderá ser utilizado para ligar pessoas e objectos ao local do crime.
Para cumprir estes objectivos, foram recolhidas e estudadas amostras da camada superficial de solo, em locais com o mesmo tipo de comunidade vegetal (floresta mista) e diferente tipo de comunidade vegetal (dunas, matagal). Para o estudo polínico foram recolhidas 5 amostras de solo por local, totalizando 30 amostras, para o estudo da mineralogia foram recolhidas 2 amostras de solo por local, totalizando 12 amostras.
Nas análises palinológicas das amostras identificaram-se 56 taxa sendo 5 de esporos, 2 de grãos de pólen de gimnospérmicas e 49 de grãos de pólen de angiospérmicas. Sempre que possível recorreu-se à caracterização das formas ao nível da espécie, contudo na maior parte dos casos a sua identificação foi feita ao nível do género.
No que respeita ao estudo geológico foi realizada a análise granulométrica através da crivagem e por difracção a laser, originando como resultados a percentagem de minerais pesados contidos em cada amostra e a percentagem de minerais de fracção menor (argilas e siltes) e de fracção maior (areias, areão e seixo). A análise mineralógica foi efectuada através do estudo dos minerais por difracção de raios x em argilas, em lâminas glicoladas e pela fracção densa, resultando em valores quantitativos de minerais de quartzo, filossilicatos e feldspatos, em valores quantitativos e semi-quantitativos de minerais de ilite, moscovite, esmectite, clorite, interstratificados e caulinite e, por último, através do estudo da fracção densa, identificaram-se ao microscópio petrográfico, para cada amostra, os minerais pesados transparentes, num total de 12 tipos (alteritos, andaluzite, anfíbola, biotite, distena, epídoto, estaurolite, granada, moscovite, silimanite, turmalina e zircão). Por fim, contabilizaram-se os minerais opacos presentes em cada amostra.Os resultados obtidos sugerem que estes dois Distritos são extremamente díspares em termos palinológicos e mineralógicos, o que vem apoiar a ideia que numa cena de crime, o estudo do solo tem uma importância crucial, salientando assim o seu valor probatório e o seu potencial forense, sendo uma extraordinária ferramenta da investigação criminal, aliando pessoas aos locais do crime e/ou pessoas com pessoas, possibilitando assim, uma maior fiabilidade na caracterização do tipo de ambiente de onde uma amostra é originária
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
Avaliação da bioatividade do muco de peixes marinhos comparação dos perfis proteicos em c. lyra e H. didactylus
No full textDissertação de Mestrado apresentada
no ISPA – Instituto Universitário para obtenção de grau de
Mestre na especialidade de Biologia Marinha e ConservaçãoO muco epidérmico é um fluido que cobre a superfície da epiderme dos peixes
formando uma barreira capaz de separar o ambiente interno do externo. O muco dos peixes
teleósteos é, tal como o de muitos outros vertebrados, produzido pelas células epidérmicas e
epiteliais.
Existem diversas espécies de peixes cujo muco epidérmico parece apresentar
propriedades bioativas e as espécies Halobatrachus didactylus e Callionymus lyra parecem
também ser exemplos disso. Uma das hipóteses a testar é que o muco produzido
abundantemente por ambas as espécies possua parecenças. Esta hipótese surge da observação
de que estes peixes, quando em estado de stress, provocam a morte de outros que com eles
partilhem um espaço confinado.
A comparação dos perfis proteicos SDS-PAGE das duas espécies, de famílias distintas
(Batrachoididae e Callionymidae), revelou algumas semelhanças. Seria o esperado caso o muco
apresentasse funções semelhantes em ambas as espécies. Para explorar em detalhe a
constituição do muco destas espécies foram ainda realizados perfis de HPLC-DAD. E, com
vista a uma potencial aplicação biomédica foram realizados ensaios antimicrobianos e
antioxidantes em C. lyra.
Os perfis de HPLC-DAD demonstraram um pico cromatográfico com 887 Da, em
ambas as espécies, podendo tratar-se do mesmo péptido. Relativamente aos ensaios, C. lyra
apresentou atividade antimicrobiana contra a bactéria Staphylococcus aureus e uma atividade
antioxidante significativa. Estes resultados preliminares são suficientemente promissores para
justificar continuar a avaliar as aplicações potenciais do muco destas espécies. No futuro, seria
interessante identificar os componentes mais promissores para diferentes aplicações em
biomedicinaABSTRACT:ABSTRACT: Epidermal mucus is a fluid that covers the surface of the epidermis of fish, forming a
barrier that separates the internal and external environment. Like many other vertebrates the
mucus of teleost fish is produced by epidermal and epithelial cells.
There are several fish species whose skin mucus presents bioactive properties and
species like Halobatrachus didactylus and Callionymus lyra are not an exception. One of the
hypotheses to be tested is that the epidermal mucus produced abundantly by both species
presents a strong effect. This hypothesis arises from the observation that these fish, in stress
conditions, are lethal for other fish species while captive in confined spaces.
The comparison of the SDS-PAGE protein profiles of the two species, families
Batrachoididae and Callionymidae, revealed some similarities. It would be expected if the
mucus had similar functions in both species. To better explore the constitution of the mucus of
these species HPLC-DAD profiles were also performed. And, with a view to a potential
biomedical application, antimicrobial and antioxidant assays were performed on C. lyra.
The HPLC-DAD profiles show a chromatographic peak with 887 Da in both species,
which could represent the same peptide. When it comes to assays, C. lyra show antibacterial
activity against gram-positive bacteria Staphylococcus aureus and a significant antioxidant
activity. Preliminary results are promising enough to justify further research to explore the
potential of the mucus produced by these species. In the future, it would be interesting to
identify the most promising mucus components for different applications in biomedicine
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