1,720,959 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
UJI AKTIVITAS ANTIOKSIDAN EKSTRAK ETANOL 96% DAUN BAKAU (RHIZOPORA APICULATE BLUM) DENGAN METODE ABTS
Full text linkLatar bekalang : Radikal bebas adalah salah satu jenis senyawa dalam jumlah berlebih akan menyebabkan stress oksidatif dan dalam jangka panjang menimbulkan berbagai penyakit degeneratif. Salah satu tumbuhan yang digunakan masyarakat adalah daun bakau (Rhizopora apiculata Blum) yang bermanfaat sebagai obat dan berfungsi sebagai sumber antioksidan alami.Tujuan : Penelitian ini dilakukan untuk menguji aktivitas antioksidan daun bakau yang diekstraksi dengan etanol 96% yang didapatkan di daerah pesisir Kota Pekalongan dan sebelumnya telah diidentifikasi senyawa fitokimia pada ekstrak tersebut.Metode : Pengujian aktivitas antioksidan dalam daun bakau menggunakan metode pemerangkapan radikal bebas ABTS karena memiliki keunggulan memberikan absorbansi spesifik pada panjang gelombang visible dan waktu rekasi yang cepat. Aktivitas antioksidan diamati menggunakan instrument Spektrofotometer UV-Visible pada panjang gelombang 700-750 nm dengan melihat nilai absorbansi untuk menentukan nilai IC₅₀. Hasil uji aktivitas antioksidan ekstrak daun bakau dapat terdeteksi menggunakan metode ABTS pada panjang gelombang 729 nm. Peredaman yang diperoleh pada ekstrak sebesar 11,29 – 32,81% dengan nilai IC50 sebesar 4,24 ppm dan termasuk dalam kategori antioksidan yang sangat kuat.Hasil : Hasil uji aktivitas antioksidan ekstrak daun bakau dapat terdeteksi menggunakan metode ABTS pada panjang gelombang 729 nm. Peredaman yang diperoleh pada ekstrak sebesar 11,29 – 32,81% dengan nilai IC50 sebesar 4,21 ppm dan termasuk dalam kategori antioksidan yang sangat kuat.Kesimpulan : Aktivitas antioksidan ekstrak etanol 96% daun bakau (Rhizopora apiculate Blum) dapat terdeteksi menggunakan metode ABTS dengan nilai IC50 sebesar 4,21 ppm dan masuk ke dalam kategori antioksidan yang sangat kuat
Penetapan Kadar Flavonoid Total berbagai Variasi Pelarut Pada Ekstrak Beras Hitam (Oryza Sativa L.Indica) Dengan Metode Spektrofotometri UV-Vis
No full textBlack rice (Oryza sativa L. Indica) is known to have a high anthocyanin compound content, and is included in the flavonoid compound group. The flavonoid content in an extract can be taken using an appropriate solvent. This shows that quality control is needed for the quality of the simplicia and the type of solvent, so that it can obtain quality secondary metabolites. The reason for this study was to determine the effect of 96% ethanol, methanol and acetone solvents on the flavonoid content of black rice extract. Black rice extract was analyzed qualitatively and the amount of flavonoid content. Quantitative testing of the amount of flavonoids used the UV-Vis spectrophotometry method. The results were analyzed using the One Way Anova strategy with a confidence level of 95%. The results showed that 96% ethanol, methanol and acetone extracts of black rice contained flavonoids, alkaloids, tannins, saponins and terpenoids. Theresults of the overall flavonoid test using the UV-Vis spectrophotometry strategyfrom 96% ethanol, methanol and acetone extracts of black rice were 8.6355 mg QE / g, respectively; 8.3713 mg QE/g and 22.4559 mg QE/g. The results of the Tukey One Way Annova test showed that the difference in solvent types had a significant effect on the flavonoid content of black rice extract with a significance value of 0.000 (p<0.05). Acetone solvents were effective in extracting flavonoid compounds compared to methanol and 96% ethanol solvent
AKTIVITAS ANTIBAKTERI EKSTRAK ETANOL 96% DAUN BAKAU (Rhizopora apiculata Blume) TERHADAP BAKTERI Streptococcus mutans MENGGUNAKAN METODE DIFUSI CAKRAM
Full text linkHasil riset kesehatan dasar menyebutkan 57,6% penduduk Indonesia mengalami permasalahan gigi dan mulut, salah satunya karies gigi. Bakteri yang berperan dalam penyebab karies gigi Streptococcus mutans. Daun bakau (Rhizopora apiculata Blume) merupakan produk alam yang mengandung metabolit sekunder. Penelitian ini bertujuan untuk mengetahui Kandungan Hambat Minimum (KHM) antibakteri ekstrak etanol 96% daun mangrove (Rhizopora apiculata Blume) terhadap Streptococcus mutans.Jenis penelitian ini adalah penelitian eksperimen. Sampel yang digunakan daun bakau (Rhizopora apiculata Blume) diekstraksi menggunakan metode maserasi dengan pelarut etanol 96%. Pengujian aktivitas antibakteri menggunakan metode difusi cakram dengan berbagai konsentrasi pada media Nutrien Agar. Kontrol positif eritromisin dan data diolah dengan One Way Anova. Hasil penelitian menunjukkan bahwa ekstrak etanol 96% daun bakau (Rhizopora apiculata Blume) mengandung metabolit sekunder flavonoid, alkaloid, tanin, saponin dan mempunyai aktivitas antibakteri terhadap bakteri Streptococcus mutans. Rata-rata konsentrasi terendah adalah 1000 ppm = 13,167 mm, dan tertinggi adalah 9000 ppm = 21 mm. Hasil uji One Way Anova signifikan. Minimum Inhibitory Level (MIC) yaitu dengan konsentrasi 1000 ppm dengan daya hambat sebesar 13,167 m
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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