1,720,954 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
Aporte de poluentes atmosféricos na APA de Petrópolis: uso de modelagem atmosférica para explicar resultados experimentais
No full textA APA-Petrópolis, localizada a 863m de altitude na Serra do Mar – RJ apresenta mais de 50% de sua área coberta por Mata Atlântica, que é considerada um “hot spot” em termos de biodiversidade mundial. Elevados fluxos de SO42-, NO3- e NH4+ estão sendo depositados na região e a origem principal desses poluentes é a Região Metropolitana do Rio de Janeiro (RMRJ) principalmente, situada a poucos quilômetros do extremo sudoeste da APA-PE. As principais espécies responsáveis pela acidez na água da chuva na APA-Petrópolis são H+, NH4+, SO42- e NO3-. O fluxo de deposição úmida de NH4+ é mais alto que o fluxo de NO3-, sendo o fluxo total (deposição seca e úmida) estimado em 14 kgN ha-1 ano-1. O excesso de N em ecossistemas tropicais acarreta uma série de danos à flora podendo levar à extinção de determinadas espécies. A fração marinha predominou para Na+, Mg2+ e Cl- e a não marinha para Ca2+, K+ e SO42-, sendo a contribuição desta fração maior durante o período úmido. É provável que as altas temperaturas estejam causando o aumento da transpiração da floresta neste período acarretando no aumento do transporte de íons de origem biológica pela ação dos ventosThe APA-Petrópolis, above 863m height in the Sea Mountain - RJ more than 50% of its area covered for Atlantic Forest, which is considered a “hot spot” of the world-wide biodiversity. High depoitions fluxes of exc-SO42-, NO3- and NH4+ have been found in this region and the major source of these pollutants seems to be the Metropolitan Region of Rio de Janeiro (RMRJ), situated near the southern boundary of the APA-Petrópolis. Those are the major chemical species controlling rainwater pH at APA-Petrópolis. The wet deposition flux of NH4+ was higher than that of NO3-. Total deposition (wet + dry) of inorganic N was estimated to be around 14,4 kgN ha-1 year-1. The excess of N in tropical ecosystems can possibly cause damages to the flora and could lead to the extinction of species. The sea-salt fraction predominated for Na+, Mg2+ and Cl- and the non-sea-salt fraction for Ca2+, K+ and SO42-. The non-sea-salt contribution predominates during the wet perio
Fluxos de óxido nitroso e potenciais fatores ambientais de controle em uma floresta tropical pluvial atlântica na Serra do Mar
No full textA área original de Mata Atlântica ocupa toda a costa brasileira e áreas do
Paraguai e Argentina. Ao longo dos anos, a floresta, considerada um hot spot em
biodiversidade mundial, vêm sendo atingida por atividades como agricultura e
urbanização que devastaram a maior parte de sua area original restando apenas
10% (100.000 km2), concentrada em regiões maior de altitude. Além disso, a
deposição atmosférica de N é elevada em regiões de Mata Atlântica como em áreas
dos Estados do Rio de Janeiro e de São Paulo; mas, pouco se sabe sobre as
consequências da deposição de N nesses ecossitemas. O estudo foi conduzido na
Serra dos Órgãos (22.782 km2), nas proximidades da Região Metropolitana do Rio
de Janeiro, Serra do Mar. A floresta é caracterizada como tropical úmida e a região
rigorosamente protegida. A vegetação varia ao longo de um gradiente altitudinal que
atinge 2,200m de altitude. Estudos relatam que a deposição atmosférica de N na
Serra dos Órgãos varia entre 14-24 kg ha-1 ano-1. A deposição de N em florestas
tropicais tende a aumentar a emissão de N2O para a atmosfera, gás de efeito estufa.
O principal objetivo foi verificar a variação nos fluxos de N2O nas áreas de
Guapimirim (~400m) e Teresópolis (~1200m), na Serra dos Órgãos; e, identificar os
principais fatores de controle do fluxo de N2O. Carbono e nitrogênio foram
analisados no solo e throughfall. Espaço de poros preenchidos por água (EPPA) e
temperatura do solo foram também verificados. Emissão de N2O foi a menor já
estimada para florestas tropicais (< 1kgN ha-1 ano-1) e fluxos de amônio na
transprecipitação foi o segundo maior já mensurado em floretas tropicais.
Temperatura do solo, EPPA, razão C/N e Ctotal foram os principais fatores
controlando os fluxos de N2O, sazonalmente. Nitrogênio orgânico dissolvido (NOD) e
o balanço entre NOD e nitrogênio inorgânico dissolvido (NOD/NID) na
transprecipitação foram positivamente correlacionados aos fluxos de N2O. Apesar da
elevada deposição atmosférica de N e da disponibilidade de N no solo, a emissão de
N2O é baixa na Serra dos Órgãos (acima de 400m); logo, torna-se necessário
verificar se o N proveniente da atmosfera estaria sendo consumido pela vegetação e
a floresta crescendo em biomassa.Coordenação de Aperfeiçoamento de Pessoal de Nível SuperiorConselho Nacional de Desenvolvimento Científico e TecnológicoAtlantic Forest is located along the Brazilian coast and inland to Paraguay and
Argentina. It has been largely devastated years ago by anthropogenic activities, such
as agriculture and urbanization. Only ten percent of its original area remains (100.000
km2), which is concentrated on high lands. Atlantic Forest is a biodiversity hotspot
that receives high nitrogen (N) input through atmospheric deposition in forests of Rio
de Janeiro; however, not much is known about the consequences of this N addition.
This study has been conducted in Serra dos Orgaos (22.782 km2) located a few
kilometers Northeast of Rio de Janeiro Metropolitan Region, Sea Mountain. The
forest, characterized as Tropical Moist Forest, is rigorously protected. Vegetation
varies along the altitudinal gradient, where the highest peak is at 2,200m asl.
Previous studies reported that N atmospheric deposition in Serra dos Orgaos varies
from 14 to 24 kg ha-1 year-1. The high N deposition on tropical forests increases
emission to the atmosphere of N2O, a greenhouse gas. The main objective of this
work was to verify the variability on fluxes of N2O in Guapimirim (~400m asl) and
Teresopolis (~1200m asl); and, identify the main factors controlling the fluxes of N2O
in Serra dos Orgaos. Carbon and nitrogen were analyzed on soil solution and
throughfall. Water filled pore space (WFPS) and soil temperature were also
quantified. Emission of N2O was the lowest one has already measured in tropical
forests (below 1kgN ha-1 year-1) while fluxes of ammonium on throughfall was the
second higher one. Water filled pore space, soil temperature, C:N ratio and Ctotal
were the main factors controlling fluxes of N2O, seasonally. Dissolved organic
nitrogen (DON) and the balance between DON and dissolved inorganic nitrogen
(DON/DIN) on throughfall were positive correlated to fluxes of N2O. So, despite of N
atmospheric deposition is high and N is available on soil, fluxes of N2O is much low in
Serra dos Orgaos; as a result, atmospheric N could be consumed by vegetation and
forest have been growing in biomass, which process should be investigated
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
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
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