1,721,024 research outputs found
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
Hantavirus infection : Insights into entry, assembly and pathogenesis
No full textHantaviruses (family Bunyaviridae, genus Hantavirus) are enveloped viruses incorporating a segmented, negative-sense RNA genome. Each hantavirus is carried by its specific host, either a rodent or an insectivore (shrew), in which the infection is asymptomatic and persistent. In humans, hantaviruses cause Hemorrhagic fever with renal syndrome (HFRS) in Eurasia and Hantavirus cardiopulmonary syndrome (HCPS) in the Americas. In Finland, Puumala virus (genus Hantavirus) is the causative agent of NE, a mild form of HFRS. The HFRS-type diseases are often associated with renal failure and proteinuria that might be mechanistically explained by infected kidney tubular cell degeneration in patients. Previously, it has been shown that non-pathogenic hantavirus, Tula virus (TULV), could cause programmed cell death, apoptosis, in cell cultures. This suggested that the infected kidney tubular degeneration could be caused directly by virus replication. In the first paper of this thesis the molecular mechanisms involved in TULV-induced apoptosis was further elucidated. A virus replication-dependent down-regulation of ERK1/2, concomitantly with the induced apoptosis, was identified. In addition, this phenomenon was not restricted to TULV or to non-pathogenic hantaviruses in general since also a pathogenic hantavirus, Seoul virus, could inhibit ERK1/2 activity.
Hantaviruses consist of membrane-spanning glycoproteins Gn and Gc, RNA-dependent RNA polymerase (L protein) and nucleocapsid protein N, which encapsidates the viral genome, and thus forms the ribonucleoprotein (RNP). Interaction between the cytoplasmic tails of viral glycoproteins and RNP is assumed to be the only means how viral genetic material is incorporated into infectious virions. In the second paper of this thesis, it was shown by immunoprecipitation that viral glycoproteins and RNP interact in the purified virions. It was further shown that peptides derived from the cytoplasmic tails (CTs) of both Gn and Gc could bind RNP and recombinant N protein. In the fourth paper the cytoplamic tail of Gn but not Gc was shown to interact with genomic RNA. This interaction was probably rather unspecific since binding of Gn-CT with unrelated RNA and even single-stranded DNA were also observed. However, since the RNP consists of both N protein and N protein-encapsidated genomic RNA, it is possible that the viral genome plays a role in packaging of RNPs into virions. On the other hand, the nucleic acid-binding activity of Gn may have importance in the synthesis of viral RNA. Binding sites of Gn-CT with N protein or nucleic acids were also determined by peptide arrays, and they were largely found to overlap.
The Gn-CT of hantaviruses contain a conserved zinc finger (ZF) domain with an unknown function. Some viruses need ZFs in entry or post-entry steps of the viral life cycle. Cysteine residues are required for the folding of ZFs by coordinating zinc-ions, and alkylation of these residues can affect virus infectivity. In the third paper, it was shown that purified hantavirions could be inactivated by treatment with cysteine-alkylating reagents, especially N-ethyl maleimide. However, the effect could not be pin-pointed to the ZF of Gn-CT since also other viral proteins reacted with maleimides, and it was, therefore, impossible to exclude the possibility that other cysteines besides those that were essential in the formation of ZF are required for hantavirus infectivity.Hantavirukset (perhe Bunyaviridae, suku Hantavirus) ovat vaipallisia negatiivi-juosteisen RNA genomin omaavia viruksia. Niiden kantajina on yleisesti pidetty jyrsijöitä, tosin viime aikoina on todettu joidenkin hyönteissyöjien myös voivan toimia kantajina hantaviruksille. Kantajissaan hantavirukset aiheuttavat pysyvän, oireettoman infektion. Sen sijaan ihmisissä osa hantavirus-lajeista tiedetään aiheuttavan munuaisoireista verenvuotokuumetta (HFRS), johon myös Suomessa esiintyvä Puumala-hantaviruksen aiheuttama myyräkuume (Nephropathia Epidemica) kuuluu. Munuaisoireiseen verenvuotokuumeeseen liittyy munuaisten vajaatoimintaa, mitä voidaan ainakin osittain selittää munuaisten tubulaarisolujen rappeutumisella. Jotkut hantavirukset kykenevät tietyissä olosuhteissa aiheuttamaan ohjattua solukuolemaa, apoptoosia, soluviljelymallissa ja on siksi mahdollista, että virus aikaansaa munuaisoireet suoran tubulaarisoluinfektion seurauksena. Tämän tutkimuksen ensimmäisessä osatyössä pyrittiin selvittämään solun signaalireittejä, jotka liittyvät hantavirusten aiheuttamaan apoptoosiin soluviljelymallissa. Solun elintoimintoja ylläpitävien kinaasien ERK1/2 aktiivisuuden havaittiin laskevan virus-infektion seurauksena, millä todennäköisesti on yhteys myös apoptoosin ilmentymiseen. ERK1/2 kinaasien esto oli merkittävin Tula-hantaviruksella, jonka uskotaan aiheuttavan oireettoman infektion ihmisessä, mutta se todennettiin myös taudinaiheuttamiskykyisillä hantaviruksilla. Hantavirukset koostuvat ulkokuoren vaippaproteiineista Gn ja Gc sekä vaipan sisälle pakkautuvista ribonukleoproteiineista (RNP). RNP:t koostuvat nukleokapsidiproteiinista N ja genomisesta RNA:sta. Jotta RNP:t voisivat pakkautua virukseen tehokkaasti, on niiden tunnistettava toinen tai molemmat viruksen vaippaproteiineista. Tämän tutkimuksen toisessa osatyössä RNP:n ja rekombinantti-tekniikalla tuotetun N proteiinin vuorovaikutus vaippaproteiinien Gn ja Gc välillä osoitettiin. Neljännessä osatyössä näytettiin että Gn kykenee sitomaan myös nukleiinihappoja, mukaan lukien viruksen genomista RNA:ta. Molemmissa aikasemmin mainituissa osatöissä käytettiin hyväksi myös peptideitä, joiden avulla vuorovaikutukset paikannettiin tiettyyn osaan Gn vaippaproteiinia. Nämä osatyöt yhdessä osoittavat, että RNP kykenee tunnistamaan viruksen vaippaproteiinit proteiini- ja nukleiinihappo-välitteisesti ja osaltaan selventävät hantavirusten koostumisen mekanismeja isäntäsolussa.
Kolmannen osatyön tarkoituksena oli tutkia hantaviruspartikkelissa olevien vapaiden tiolien roolia viruksen sisäänmenossa isäntäsoluun. Tulokset osoittivat että vapaat tiolit ovat ratkaisevassa osassa tässä prosessissa ja että hantavirusten infektiivisyys kyetään estämään tioleja alkyloivilla yhdisteillä. Hantavirusten käsittely tiolien kanssa reagoivilla yhdisteillä ei heikentänyt virusten antigeenisuutta osoittaen, että tällä tavoin inaktivoitu hantavirus voi olla hyödyllinen diagnostiikassa tai ehkä jopa rokotteena.ei saavutettav
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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