1,720,956 research outputs found
Aktivitas Antioksidan dan Kandungan Total Fenolik serta Flavonoid Ekstrak Etanol Tanaman Krokot (Portulaca grandiflora Hook.)
No full textAntioksidan diperlukan untuk menangkal radikal bebas dalam tubuh serta stress oksidatif yang mendorong proses penuaan dan berbagai penyakit degeneratif. Portulaca grandiflora Hook. diketahui memiliki potensi sebagai antioksidan. Perbedaan fungsi organ tanaman menyebabkan perbedaan jalur biosintesis kandungan fitokimia yang terdapat pada tiap organ tanaman. Hal ini dapat mempengaruhi aktivitas antioksidannya. Penelitian ini bertujuan mengukur kandungan total fenolik dan flavonoid pada organ daun, batang tua, batang muda, dan bunga dari tanaman krokot (Portulaca grandiflora Hook.) yang diekstrak menggunakan etanol 96% dan menentukan aktivitas antioksidan dari ekstrak tersebut dengan uji DPPH (2,2-difenil-1-pikrihidrazil). Ekstrak etanol krokot mengandung senyawa fenolik dan flavonoid yang berbeda tiap organ tanaman. Kandungan total fenolik dan flavonoid paling tinggi terdapat pada ekstrak etanol daun krokot yaitu, sebesar 113.26 ± 3.85 mg GAE/g dan 97.99 ± 1.28 mg QE/g. Ekstrak etanol batang tua krokot tergolong antioksidan sedang dengan nilai IC50 122.15 ± 1.30 ppm
Studi In Silico dan Dinamika Molekuler Pada Senyawa Bioaktif Bidara Laut (Strychnos nux-vomica) Yang Berpotensi Menghambat Kanker Payudara Jalur PI3K/AKT
Get PDFLatar belakang: Tingginya kasus kanker payudara baik di dunia dan Indonesia, serta progresivitas penyakit tersebut yang kompleks memerlukan pengobatan yang tepat dengan menargetkan salah satu jalur pensinyalan, yaitu jalur PI3K/AKT yang terlibat dalam karsinogenesis payudara. Senyawa bioaktif bidara laut seperti strychnine, brucine, adenosine, lupeol, catechol, dan maltol bepotensi sebagai antikanker payudara. Studi in silico dan dinamika mampu memberikan gambaran potensi senyawa bioaktif bidara laut dalam menghambat kanker payudara jalur PI3K/AKT. Tujuan: Menganalisis target potensial senyawa bioaktif bidara laut, profil drug-likeness dan farmakokinetik serta toksisitasnya, potensi pengikatan dengan reseptor target, serta kestabilannya melalui metode in silico dan simulasi dinamika molekuler. Hasil: Senyawa bioaktif bidara laut dapat menargetkan TP53, AKT1, GAPDH, IL6, CTNNB1, EGFR, ESR1, INS, SRC, dan PTEN. Senyawa ini juga memenuhi aturan Lipinski serta memiliki profil farmakokinetik dan toksisitas yang baik secara umum, serta dapat menghambat AKT1 melalui sisi aktif dan alosterik dengan energi afinitas terendah, yaitu senyawa brucine (-10,83 kJ/mol) lebih baik daripada standar capivasertib pada sisi aktif dan lupeol (-11,14 kJ/mol), namun tidak lebih baik dari standar MK-2206 pada sisi alosterik. Adapun hasil simulasi dinamika molekuler masih menunjukkan adanya perubahan nilai dalam waktu 5 ns pada semua parameter. Kesimpulan: Studi in silico dan dinamika molekuler dapat menggambarkan potensi senyawa bioaktif bidara laut (Strychnos nux-vomica) dalam menghambat kanker payudara jalur PI3K/AKT. Senyawa bioaktif bidara laut memenuhi aturan Lipinski dan secara umum memiliki profil farmakokinetik dan toksisitas yang baik, serta dapat bekerja dengan menghambat AKT1 baik pada sisi aktif maupun alosterik. Namun, senyawa bioaktif bidara laut belum menunjukkan kestabilan ikatan dengan reseptornya dalam waktu 5 ns
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
Inhibition breast carcinogenesis via PI3K/AKT pathway using bioactive compounds of Strychnine tree (Strychnos nux-vomica): in silico study
Get PDFBreast cancer poses a significant global health challenge, with a notable prevalence in Indonesia. Given the intricate nature of breast cancer progression and classification, precise treatment strategies are imperative, particularly targeting signaling pathways like PI3K/AKT, pivotal in cell growth, proliferation, survival, and apoptosis. Bioactive compounds from the Strychnine tree demonstrate potential in enhancing apoptotic effects and inhibiting breast carcinogenesis. This potential is explored through in silico studies. This research aims to analyze potential targets of Strychnine tree compounds, along with binding energy and stability between ligands and receptors. Employing bioinformatics target analysis, molecular docking, and molecular dynamics simulation, the study reveals AKT1 as a potential target of Strychnine tree compounds. These compounds inhibit AKT1 at both active and allosteric sites, displaying notably low binding energy scores. For example, brucine exhibits a binding energy of -10.83 kJ/mol at the active site, surpassing the standard capivasertib. However, lupeol, with a binding energy of -11.14 kJ/mol, falls short of the MK-2206 standard at the allosteric site. Molecular dynamics simulations expose fluctuations in parameters like RMSD, RMSF, and binding energy within the initial 5 ns. In conclusion, Strychnine tree compounds, such as brucine and lupeol, showcase potential AKT1 inhibition at both active and allosteric sites, enhancing apoptotic effects. However, the stability of these compounds in binding to their receptors within the first 5 ns of the simulation warrants further investigation for prolonged interactions.
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
- …
