1,721,959 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
Markers for mitotic catastrophe in sodium valproate-treated HeLa cells
No full textThe data set shows features for immunofluorescence signals which identify caspase-2 and p53 in HeLa cells cultured in the presence of 1 mM and 20 mM sodium valproate (VPA) for 4 h, and 20 mM VPA for 48 h. These proteins are ascribed to be potentially associated with the incidence of mitotic catastrophe, an oncosupressive event. Cells were fixed in methanol at -20 °C for 10 min, rinsed in PBS, permeabilized with 0.2% Triton X-100 for 10 min, and blocked in 5% BSA for 1 h. Rabbit anti-caspase-2 and anti-p53 were used as primary antibodies (1:200 and 1:100 dilutions, respectively). Goat anti-rabbit conjugated with Alexa-Fluor 488 (1:500 dilution) was used as secondary antibody. The images were captured in a Leica TCS SP5 II confocal microscope at the Laboratório Central de Tecnologias de Alto Desempenho em Ciências da Vida (LaCTAD/UNICAMP). The evaluated features were: total fluorescence area, mean gray value (average pixel intensity within a region of interest), standard deviation, minimum and maximal intensity (lowest and highest pixel intensity value within a region, respectively), integrated density (backgound-normalized sum of the pixel intensity values within the image or selection), and raw integrated density (sum of the values of the image pixels)
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
Image cytometry of sodium valproate- and 5-aza-CdR-treated U-251MG glioblastoma cells
No full textThe dataset identifies nuclear cytometry features of Feulgen-stained U-251MG glioblastoma cells cultured in the presence of sodium valproate using 5-aza-CdR treatment as a control of DNA demethylation. The cells were cultured in the presence of 10 µM lovastatin for 28 h for synchronization and then in the presence of 1- and 20-mM sodium valproate for 4 and 24 h. Treatment with 5 µM 5-aza-CdR was carried out for 28 h. The preparations were fixed in an absolute ethanol-acetic acid mixture (3:1, v/v) for 5 min and subjected to the Feulgen reaction for studying nuclear features evaluated with image cytometry using KS400-version 3 software. The features analyzed were as follows: total nuclear area (µm2), nuclear absorption area (µm2), Feret ratio, optical density (= absorbance), integrated optical density (IOD), absorbance variability per nucleus (SDtd), nuclear entropy (number of bits required to store the densitometric values per nuclear image), and nuclear energy
Data on survival and molting incidence of Triatoma infestans (Klug) and Panstrongylus megistus (Burmeister) (Hemiptera, Reduviidae) after blood intake from anaesthetized chickens
No full textMuch of the knowledge on cell biology, survival and molting rates in the insect vectors of Chagas disease, Triatoma infestans (Klug) and Panstrongylus megistus (Burmeister), raised in the late 20th century has been obtained from specimens fed blood intake from non-anaesthetized chickens. Avian blood intake for these insects in research facilities has been a recommendation to avoid Trypanosoma cruzi infection. Currently, the protocols for these insects’ rearing in research facilities demand that the chicken – source of blood intake – be anaesthetized by an accredited veterinary and that the welfare of the birds be monitored before, during and after the blood intake the insects receive. These protocols are conducted to ensure that the birds do not suffer from unwarranted pain or distress. Data on survival and molting incidence are presented for specimens of T. infestans and P. megistus fed on blood from chickens anaesthetized with ketamine/xylazine consistent with the recommendation by ethical committees on animal experimentation. These data constitute an important basis for comparisons with data provided by insects that ingested blood from non-anaesthetized sources or from animals anaesthetized with drugs other than ketamine/xylazine, preceding various experimental conditions. The specimens used originated from populations of insects collected since 1980, in the north of the state of Minas Gerais (Brazil) (Vale do Jequitinhonha) (between latitudes16 °S and 18 °S and longitudes 41 °W and 43 °W (T. infestans) and in the east region of the state of São Paulo (Brazil) (between latitudes 21 °31’S and 21 °58’S and close to the longitude 46 °40’W (P. megistus). Inbreeding has been avoided by periodically collecting and introducing new specimens to the previously established colonies. The animal care and ethical procedures to rear these insects are registered at the National Council of Animal Experimentation Control (COBEA) from the Brazilian Ministry of Science, Technology and innovation under accreditation protocol no. 01200.003280/2014-28. The SUCEN Scientific and Ethics Committee approved this study (Protocol no. 64,405/2015)
Infrared data of sodium valproate (VPA), histones and VPA-histone mixtures
No full textThe dataset identifies infrared microspectroscopical spectral absorbances (FTIR) for construction of spectral signatures and mathematical analyses to identify the effect of sodium valproate (VPA) on chromatin histone components and to expand the understanding of the pharmacological potential of this drug
- …
