1,720,986 research outputs found
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
Diversity, aggressiveness and pathogenicity of Meloidogyne spp. in sugarcane and prospect of genetic resistance in genotypes adapted to Southern Brazil
No full textAmong the problems affecting sugarcane crop, plant-parasitic nematodes can result in potential crop damage. The present study was carried out in in three chapters. In the first, Meloidogyne spp. populations sampled in sugarcane location of Rio Grande do Sul state, were characterized through the esterase (Est) activity where part of them were evaluated as the physiological races. Subsequently, 35 populations of
Meloidogyne spp. from this study and the work of Bellé (2014) were molecularly characterized by SCAR and RAPD markers. In the second chapter, efforts were done to evaluate the aggressiveness of different populations of M. javanica and M. incognita in different sugarcane genotypes. The last step of this study aimed to evaluate the reaction of 25 sugarcane genotypes to M. incognita and M. javanica. Additionally, the effects of two root-knot species was monitored based on the development of inoculated plants(a); the response of parasitized plants by M. incognita, M. javanica and M. arenaria on the Meloidogyne spp. reproduction, vegetative development, shoot production, content sugars and components of the shoot cell wall of sugarcane plants. Finally, the pathogenicity of low-frequency Meloidogyne species were quantified.
Meloidogyne spp. was detected at 92.6% of the collected samples and M. incognita Est I2 was the most frequent species (51.3%). Among M. incognita populations physiologically characterized, the races 1, 2, 3 and 4 were identified; however, it was not possible to correlate them with the respective esterase phenotypes. The use of SCAR markers allowed to differentiate most of the Meloidogyne populations by
amplifying species-specific fragments for M. javanica (670 bp), M. incognita (399 bp), M. arenaria (420 bp) and M. javanica (670 bp), M. morocciensis (420 bp), M. ethiopica (350 bp) and M. enterolobii (520 bp). By RAPD analysis, 234 and 394 reproducible fragments were amplified, whose the percentage of amplified polymorphic bands ranged from 21.0 to 31.5%, respectively. By the phylogenetic analysis, four groups
were formed: in the first one, 16 populations of M javanica were grouped; in the second, M. arenaria and M. morocciensis; in the third, M. incognita and Meloidogyne sp. Est. SC1; and, M. ethiopica, M. luci and M. enterolobii were grouped separately. Evaluating the aggressiveness of the populations of Meloidogyne spp., there was a significant interaction between sugarcane genotypes and nematode populations for the variables related to nematode reproduction and damage caused in the roots, as well as growth plant parameters, fiber digestibility, sugars content and cell wall components. Considering the sugarcane reaction to M. javanica and M. incognita, all genotypes were susceptible in different degrees; these nematode species interfered on the development of the plants. Evaluating the pathogenicity of M. luci, M. enterolobii, M. morocciensis, M. hapla, M. arenaria and M. ethiopica, all species reproduced (10.2> RF <50.5) on sugarcane and affected negatively the vegetative development of this crop.Sem bolsaEntre os problemas que afetam a cultura da cana-de-açúcar, os fitonematoides podem resultar em sérios prejuízos. Nesse sentido, o presente estudo foi dividido em três capítulos. No primeiro, populações de Meloidogyne spp. advindas de coletas em
regiões canavieiras do Rio Grande do Sul, foram caracterizadas bioquímica e fisiologicamente através da enzima esterase (Est) sendo parte delas, avaliadas quanto as raças fisiológicas. A seguir, 35 populações de Meloidogyne spp. provenientes deste
estudo e do trabalho de Bellé (2014), foram caracterizadas molecularmente por marcadores do tipo SCAR e RAPD. No segundo capítulo, avaliou-se a agressividade de diferentes populações de M. javanica e M. incognita em diferentes genótipos de
cana-de-açúcar. E, no terceiro, avaliou-se, em casa de vegetação, a reação de 25 genótipos de cana-de-açúcar a M. incognita e M. javanica além dos efeitos dessas espécies sobre o desenvolvimento das plantas inoculadas; e, o comportamento de
plantas parasitadas por M. incognita, M. javanica e M. arenaria quanto à reprodução, desenvolvimento vegetativo, produção de colmos, açúcares e componentes da parede celular da parte aérea. Por fim, estudou-se a patogenicidade de espécies de
Meloidogyne de menor frequência em cana-de-açúcar. Verificou-se a presença de Meloidogyne spp. em 92,6% das amostras coletadas, sendo M. incognita Est I2, a espécie mais frequente (51,3%). Entre as populações de M. incognita caracterizadas
fisiologicamente, identificou-se as raças 1, 2, 3 e 4, todavia, não foi possível correlacioná-las com os respectivos fenótipos de esterase. Através dos marcadores SCAR foi possível a diferenciação da maioria das espécies de Meloidogyne estudadas, através da amplificação de fragmentos espécie-específicos para populações de M. javanica (670 pb), M. incognita (399 pb), M. arenaria (420 pb), M. morocciensis (420 pb), M. ethiopica (350 pb) e M. enterolobii (520 pb). Pela análise RAPD, 234 e 394 fragmentos reprodutíveis foram amplificados, cuja percentagem de bandas polimórficas amplificadas variou de 21,0 a 31,5%, respectivamente. Pela análise filogenética, quatro grupos se formaram: no 1o, agruparam-se 16 populações de M javanica; no 2
o, M. arenaria e M. morocciensis; no 3o, M. incognita e Meloidogyne sp. Est. SC1; e, M. ethiopica, M. luci e M. enterolobii se agruparam separadamente. Avaliando-se a agressividade das populações de Meloidogyne spp., verificou-se, interação significativa entre genótipos de cana-de-açúcar e populações dos nematoides para as variáveis relacionadas a reprodução e danos causados nas raízes, assim como também em relação aos parâmetros de crescimento das plantas, digestibilidade de fibras, açúcares e componentes da parede celular. Em relação à reação da cana-de-açúcar a M. javanica e M. incognita, todos os genótipos foram suscetíveis (diferentes graus), havendo interferência dessas espécies sobre o desenvolvimento das plantas. Nos testes de patogenicidade, M. luci, M. enterolobii, M. morocciensis, M. hapla, M. arenaria e M. ethiopica reproduziram-se (10,2>FR<50,5) em cana-de-açúcar, e afetaram negativamente o desenvolvimento vegetativo da cultura
Diversity, aggressiveness and pathogenicity of Meloidogyne spp. in sugarcane and prospect of genetic resistance in genotypes adapted to Southern Brazil
No full textAmong the problems affecting sugarcane crop, plant-parasitic nematodes can result in potential crop damage. The present study was carried out in in three chapters. In the first, Meloidogyne spp. populations sampled in sugarcane location of Rio Grande do Sul state, were characterized through the esterase (Est) activity where part of them were evaluated as the physiological races. Subsequently, 35 populations of
Meloidogyne spp. from this study and the work of Bellé (2014) were molecularly characterized by SCAR and RAPD markers. In the second chapter, efforts were done to evaluate the aggressiveness of different populations of M. javanica and M. incognita in different sugarcane genotypes. The last step of this study aimed to evaluate the reaction of 25 sugarcane genotypes to M. incognita and M. javanica. Additionally, the effects of two root-knot species was monitored based on the development of inoculated plants(a); the response of parasitized plants by M. incognita, M. javanica and M. arenaria on the Meloidogyne spp. reproduction, vegetative development, shoot production, content sugars and components of the shoot cell wall of sugarcane plants. Finally, the pathogenicity of low-frequency Meloidogyne species were quantified.
Meloidogyne spp. was detected at 92.6% of the collected samples and M. incognita Est I2 was the most frequent species (51.3%). Among M. incognita populations physiologically characterized, the races 1, 2, 3 and 4 were identified; however, it was not possible to correlate them with the respective esterase phenotypes. The use of SCAR markers allowed to differentiate most of the Meloidogyne populations by
amplifying species-specific fragments for M. javanica (670 bp), M. incognita (399 bp), M. arenaria (420 bp) and M. javanica (670 bp), M. morocciensis (420 bp), M. ethiopica (350 bp) and M. enterolobii (520 bp). By RAPD analysis, 234 and 394 reproducible fragments were amplified, whose the percentage of amplified polymorphic bands ranged from 21.0 to 31.5%, respectively. By the phylogenetic analysis, four groups
were formed: in the first one, 16 populations of M javanica were grouped; in the second, M. arenaria and M. morocciensis; in the third, M. incognita and Meloidogyne sp. Est. SC1; and, M. ethiopica, M. luci and M. enterolobii were grouped separately. Evaluating the aggressiveness of the populations of Meloidogyne spp., there was a significant interaction between sugarcane genotypes and nematode populations for the variables related to nematode reproduction and damage caused in the roots, as well as growth plant parameters, fiber digestibility, sugars content and cell wall components. Considering the sugarcane reaction to M. javanica and M. incognita, all genotypes were susceptible in different degrees; these nematode species interfered on the development of the plants. Evaluating the pathogenicity of M. luci, M. enterolobii, M. morocciensis, M. hapla, M. arenaria and M. ethiopica, all species reproduced (10.2> RF <50.5) on sugarcane and affected negatively the vegetative development of this crop.Sem bolsaEntre os problemas que afetam a cultura da cana-de-açúcar, os fitonematoides podem resultar em sérios prejuízos. Nesse sentido, o presente estudo foi dividido em três capítulos. No primeiro, populações de Meloidogyne spp. advindas de coletas em
regiões canavieiras do Rio Grande do Sul, foram caracterizadas bioquímica e fisiologicamente através da enzima esterase (Est) sendo parte delas, avaliadas quanto as raças fisiológicas. A seguir, 35 populações de Meloidogyne spp. provenientes deste
estudo e do trabalho de Bellé (2014), foram caracterizadas molecularmente por marcadores do tipo SCAR e RAPD. No segundo capítulo, avaliou-se a agressividade de diferentes populações de M. javanica e M. incognita em diferentes genótipos de
cana-de-açúcar. E, no terceiro, avaliou-se, em casa de vegetação, a reação de 25 genótipos de cana-de-açúcar a M. incognita e M. javanica além dos efeitos dessas espécies sobre o desenvolvimento das plantas inoculadas; e, o comportamento de
plantas parasitadas por M. incognita, M. javanica e M. arenaria quanto à reprodução, desenvolvimento vegetativo, produção de colmos, açúcares e componentes da parede celular da parte aérea. Por fim, estudou-se a patogenicidade de espécies de
Meloidogyne de menor frequência em cana-de-açúcar. Verificou-se a presença de Meloidogyne spp. em 92,6% das amostras coletadas, sendo M. incognita Est I2, a espécie mais frequente (51,3%). Entre as populações de M. incognita caracterizadas
fisiologicamente, identificou-se as raças 1, 2, 3 e 4, todavia, não foi possível correlacioná-las com os respectivos fenótipos de esterase. Através dos marcadores SCAR foi possível a diferenciação da maioria das espécies de Meloidogyne estudadas, através da amplificação de fragmentos espécie-específicos para populações de M. javanica (670 pb), M. incognita (399 pb), M. arenaria (420 pb), M. morocciensis (420 pb), M. ethiopica (350 pb) e M. enterolobii (520 pb). Pela análise RAPD, 234 e 394 fragmentos reprodutíveis foram amplificados, cuja percentagem de bandas polimórficas amplificadas variou de 21,0 a 31,5%, respectivamente. Pela análise filogenética, quatro grupos se formaram: no 1o, agruparam-se 16 populações de M javanica; no 2
o, M. arenaria e M. morocciensis; no 3o, M. incognita e Meloidogyne sp. Est. SC1; e, M. ethiopica, M. luci e M. enterolobii se agruparam separadamente. Avaliando-se a agressividade das populações de Meloidogyne spp., verificou-se, interação significativa entre genótipos de cana-de-açúcar e populações dos nematoides para as variáveis relacionadas a reprodução e danos causados nas raízes, assim como também em relação aos parâmetros de crescimento das plantas, digestibilidade de fibras, açúcares e componentes da parede celular. Em relação à reação da cana-de-açúcar a M. javanica e M. incognita, todos os genótipos foram suscetíveis (diferentes graus), havendo interferência dessas espécies sobre o desenvolvimento das plantas. Nos testes de patogenicidade, M. luci, M. enterolobii, M. morocciensis, M. hapla, M. arenaria e M. ethiopica reproduziram-se (10,2>FR<50,5) em cana-de-açúcar, e afetaram negativamente o desenvolvimento vegetativo da cultura
Nematofauna population dynamics, its inter-relation with soil-borne diseases in potato (Solanum tuberosum L.) crop succession and reaction of cover crops to Meloidogyne ethiopica as a component of integrated management of plant parasitic nematodes
No full textOs nematoides fitoparasitas entre outros patógenos de solo representam sérias ameaças ao cultivo da batata. No entanto, identificar a etiologia de tais patógenos, entender tais patossistemas bem como integrar medidas de controle são importantres no estabelecimento de estratégias de manejo em sistemas de produção. Nesse sentido, foram objetivos deste trabalho: a) identificar as espécies do nematoide-das-galhas e das lesões presentes em uma área de produção de batata sob pivo central no Triângulo Mineiro MG; b) avaliar a reação de diferentes culturas de cobertura a M. ethiopica; c) estudar a dinâmica populacional da nematofauna em campo após o uso de culturas de cobertura durante um ciclo de sucessão (inverno-verão-inverno); e d) avaliar o efeito de coberturas sobre a ocorrência e sintomas de doenças de solo na batata cultivada em sucessão. As espécies de Pratylenchus foram identificadas com base em características morfológicas e morfométricas. As espécies de Meloidogyne foram identificadas por meio de caracterização bioquímica utilizando-se a isoenzima esterase. A área em estudo foi dividida em 18 faixas para o cultivo de nove diferentes culturas de cobertura repetidas duas vezes, no inverno 2020, estimando-se as populações dos fitonematoides (solo e raízes) antes e após cultivo de cada cobertura. Após o cultivo das plantas de cobertura, foi realizada a semeadura de milho na safra verão 2020/2021 e, em seguida, o cultivo de batata na safra inverno 2021, estimando-se ao final de cada ciclo, as populações dos fitonematoides no solo e nas raízes das plantas. Por fim, 11 genótipos de diferentes coberturas foram avaliados quanto ao fator de reprodução (FR) e reação a M. ethiopica, em casa de vegetação por duas vezes. Foram identificadas na área experimental as espécies P. brachyurus, P. zeae, M. ethiopica (Est E3) e M. arenaria (Est A2). Nas avaliações da reação das coberturas a M. ethiopica, em casa-de-vegetação, as espécies de crotalária, C. juncea, C. breviflora, C. spectabilis e C. ochroleuca foram imunes (FR=0,00); aveia-preta, braquiária ruziziensis, crambe, milheto cvs. BRS 1501 e ADR 300, mucuna-cinza, nabo-forrageiro, rúcula cv. Nemat, sorgo cv. Ponta Negra, trigo cv. Duque e trigo-mourisco foram más hospedeiras do nematoide, comportando-se como resistentes (FR1,00) em pelo menos uma das avaliações. Todas as culturas de cobertura reduziram as populações de Pratylenchus spp. no solo, exceto o trigo cv. BRS 264. As demais reduziram as populações de Meloidogyne spp. e Helicotylenchus sp. Os níveis populacionais dos nematoides de vida-livre no solo foram incrementados com as coberturas especialmente Crotalaria juncea; e, reduzidos após o primeiro ciclo de cultivo do milho. O efeito de redução dos três gêneros de nematoides fitopatogênicos estudados não persistiu para além do cultivo de milho, a não ser nos casos do trigo cv. BRS 264 e do mix crotalárias, que demonstraram decréscimo na população de Meloidogyne spp. durante o cultivo do milho. Já, após o cultivo de batata, houve incremento nos níveis populacionais de Meloidogyne spp. no solo independentemente da cultura de cobertura. Por fim, o cultivo do consórcio C. breviflora + C. ochroleuca resultou na redução da incidência de lesões necróticas causadas por Pratylenchus spp. nas raízes de batata.Phytoparasitic nematodes and other soil diseases pose serious threats to potato cultivation. The objectives of this research were (a) to identify the species of root-knot nematodes and lesion nematodes present in a potato production area in the Triângulo Mineiro MG region; (b) to evaluate the nematofauna dynamics in the field after cover crops during a crop succession cycle; (c) to evaluate the cover crops effect on the occurrence of soil-borne disease symptoms in potatoes grown in succession; and (d) to evaluate the reaction of different cover crops to M. ethiopica. Pratylenchus species were identified through morphometric characteristics and Meloidogyne species were identified through biochemical characterization. The area under study was divided into 18 strips for the cultivation of nine cover crops, in a randomized complete block design, with two replications, in the 2020 winter season. Following the cover crops, corn was cultivated in the summer 2020/ 2021 and then potato was cultivated in the winter 2021. Finally, 11 cover crop genotypes were evaluated over four experiments in pots, inoculated with M. ethiopica. The species P. brachyurus, P. zeae, M. ethiopica and M. arenaria were identified. All cover crops reduced the population of Pratylenchus spp. in the soil and all of them, except wheat cv. BRS 264, reduced the population of Meloidogyne spp. Helicotylenchus sp. was reduced by all cover crops except buckwheat. The free-living nematode population was increased by cover crops, especially Crotalaria juncea. The free-living nematode population was reduced to less than the initial values after the first crop cycle (corn). The reduced population of phytoparasitic nematodes did not persist beyond corn cultivation, except in the cases of wheat cv. BRS 264 and the crotalaria mix, which demonstrated a decrease in the population of Meloidogyne spp. during corn cultivation. This effect, however, did not persist during potato cultivation, which increased the population of Meloidogyne spp. in the soil regardless of the cover crop. At the end of the potato cycle, all nematodes had populations higher than the initial, regardless of the cover crop used. The cultivation of the C. breviflora + C. ochroleuca intercrop reduced the incidence of longitudinal necrotic lesions on the roots attributed to Pratylenchus sp. Oats, black-oats and crambe mix provided a reduction in the incidence of verticillium wilt. The use of oats as a cover crop provided a reduction in the incidence of powderyscab on tubers. In greenhouse experiments, Crotalaria species presented gall index and reproduction factor (FR) values equivalent to the resistant control in all evaluations, with C. juncea, C. breviflora, C. spectabilis and C. ochroleuca presenting FR values equal to zero (immune). Black-oats, braquiária, crambe, millet cvs. BRS 1501 and ADR 300, velvetbeans, fodder radish, arugula cv. Nemat, sorghum cv. Ponta Negra, wheat cv. Duke and buckwheat presented FR values below 1.00 (nonmultiplier plants). Mustard cvs. Common and Bioactive and wheat cvs. Atom and BRS 264 presented a FR value equal to or greater than 1.00 in at least one of the evaluations, being not recommended
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
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
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