1,720,960 research outputs found
Homogenisasi Substrat Pertanian dengan Droplet Microfluidics Frekuensi Tinggi
No full textMasalah dalam pencampuran material mentah dalam saluran mikro merupakan masalah pencampuran klasik dalam microfludic, dan banyak solusi yang telah ditawarkan. Terdapat pada beberapa kasus masalah pencampuran dalam saluran mikro tidak terpecahkan dengan baik. Oleh sebab itu permasalahan ini akan dicoba untuk diselesaikan dalam penelitian ini. Secara spesifik, masalah dalam pencampuran material granular basah dalam saluran mikro berbeda dengan pencampuran cairan pada umumnya yang dilakukan pada alat yang sama. Penelitian ini bertujuan untuk (1) Mendapatkan struktur desain chip yang baru berdasarkan kalkulasi teori, dan membuat chip microfluidics berdasarkan desain tersebut; (2) Menguji kinerja chip microfluidics. Kedua tujuan ini bermaksud untuk mendapatkan distribusi yang homogen dari material mentah di dalam droplet microfluidics. Desain yang baik adalah yang memiliki standar deviasi (σ) gray scale 85%. Untuk mencapai tujuan ini, dibuat beberapa desain microfluidic dan masingmasing dibandingkan satu sama lain dan juga dengan desain standar. Beberapa perlakuan awal juga dianalisis untuk mengurangi heterogenitas lebih jauh. Derajat homogenitas diperoleh dengan menganalisa distribusi kehitaman (gray scale) yang dideteksi pada frame 8-bit video yang direkam dengan kamera berkecepatan tinggi dan dianalisis pada MATLAB®. Dua tipe material granular pertanian yang digunakan dalam penelitian ini adalah dedak gandum dan rapeseed. Dalam penelitian dibuat 10 rancangan desain dan perlakuan untuk mendapatkan hasil yang terbaik. Hasil dari penelitian didapatkan bahwa :1) Terjadi peningkatan nilai terisi di dalam droplet dibandingkan desain standar yaitu : untuk dedak gandum dari 65.59% menjadi 99.98%, dan untuk rapeseed dari 65.33% menjadi 97%; 2). Didapatkan peningkatan homogenitas dari material mentah di dalam droplet dibandingkan dengan desain standar yaitu : untuk dedak gandum dari 15.78% menjadi 7.33%, dan untuk rapeseed dari 27.92% menjadi 12.1%; 3) Homogenitas ukuran diameter droplet juga berhasil ditingkatkan yaitu : untuk dedak gandum dari 10.99% menjadi 0.10%, dan rapeseed dari 16.09% menjadi 0.83%
Criblage combinatoire d'antibiotiques à l'aide de la microfluidique en gouttelettes
No full textDe nos jours, nous vivons à l'époque où la résistance aux antibiotiques est devenue une grave menace mondiale. L'une des solutions pour découvrir de nouveaux antibiotiques est de combiner des médicaments existants qui ont été approuvés par la FDA. Cependant, cette via les méthodes conventionnelles est très coûteuse et lente. Le but de ce projet est de combiner les antibiotiques à l'aide de la microfluidique en gouttelettes pour surmonter ces limites. Tout d'abord, nous avons caractérisé la croissance bactérienne dans les gouttelettes et calibrons un dosage de croissance de fluorescence à haut débit en utilisant Syto-9. Ensuite, nous avons sélectionné un ensemble de 11 antibiotiques qui ne fuient pas des gouttelettes aux gouttelettes. Nous présentons une technique pour émulsifier en parallèle jusqu'à 96 puits contenant des antibiotiques à différentes doses. Nous avons montré ensuite comment le couplage et la fusion microfluidiques permettent de combiner différentes bibliothèques de médicaments. Enfin, nous avons présenté une preuve de concept d'une mesure des interactions médicamenteuses dans les gouttelettes. Dans la dernière partie de ce travail, nous avons élaboré une stratégie de codage par l'ADN pour identifier les interactions médicamenteuses par séquençage après une étape de tri basée sur le test de croissance. Pour conclure, nous avons conçu et optimisé les différents modules microfluidiques au niveau suffisant pour pouvoir être combinés de manière robuste. Ils peuvent fournir une plate-forme technologique capable de réduire les coûts et le temps de dosage pour les combinaisons de médicaments à l'échelle du laboratoire avant l'essai clinique.Nowadays, we are living in the era where antibiotic resistance has become a serious worldwide threat. One of the solution to discover novel antibiotics is to combine existing drugs that have been approved by FDA. However, drug combination using conventional method is highly expensive and has low throughput. The aim of this project is to combine antibiotics using droplet microfluidics to overcome these limitations. First, we show how to control the encapsulation of bacteria E. coli MG1655 by correlating Poisson distribution and OD (Optical Density) for different volume of droplets. We then characterize bacterial growth inside droplets and calibrate a high-throughput fluorescence growth assay using Syto-9. Then, we select a set of 11 antibiotics that do not leak from droplets to droplets and represent major classes of mechanisms. We present a technique to emulsify in parallel up to 96 wells containing antibiotics at different doses. We then show how microfluidic pairing and fusion allow to combine different drug-dose libraries. Finally, we present a proof of concept of a measurement of drug interactions in droplets. In the last part of this work, we elaborate a DNA barcoding strategy to identify drug interactions by sequencing after a sorting step based on the growth assay. To conclude, we have designed and optimized the different microfluidic modules to level sufficient so that they can be combined robustly. It can provide a technological platform that is able to reduce cost and assay time for drug combinations at a laboratory scale, before clinical trial
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
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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