1,720,978 research outputs found
Approaching single DNA molecule detection with an ultrasensitive electrochemical genosensor based on gold nanoparticles and Cobalt-porphyrin DNA conjugates
No full textWe describe an ultrasensitive electrochemical genosensor based on gold nanoparticles and cobalt-porphyrin functionalised ssDNA probes. The sensitivity at the attomolar concentration level arises from an increased density of redox labels on the electrode surface compared to sensors without NP modification. The electrode detects as few as 23 DNA molecules, approaching single molecule detection
Silver or gold? A comparison of nanoparticle modified electrochemical genosensors based on cobalt porphyrin-DNA
No full textWe applied a cobalt-porphyrin modified DNA as electrochemical marker, which was attached to nanoparticles, to detect specific DNA sequences. We compare the performance of gold and silver NPs in oligonucleotide sensors to determine if a change in metal will lead to either higher sensitivity or different selectivity, based on the redox behaviour of silver vs. gold. Surprisingly, we find that using either gold or silver NPs yields very similar overall performance. The electrochemical measurements of both types of sensors show the same redox behaviour which is dominated by the cobalt porphyrin, indicating that the electron pathway does not include the NP, but there is direct electron transfer between the porphyrin and the electrode. Both sensors show a linear response in the range of 5 × 10–17 to 1 × 10–16 M; the limit of detection (LOD) is 3.8 × 10–18 M for the AuNP sensor, and 5.0 × 10–18 M for the AgNP sensor, respectively, which corresponds to the detection of about 20–50 DNA molecules in the analyte. Overall, the silver system results in a better DNA economy and using cheaper starting materials for the NPs, thus shows better cost-effectiveness and could be more suitable for the mass-production of highly sensitive DNA sensors
Bilingual Education: A Constructive Support
No full textВ современном взаимосвязанном мире двуязычие заставляет любого выделяться из толпы и идти впереди. Во многих учебных заведениях Индии двуязычное образование является неотъемлемой частью учебной программы, оно обеспечивает ребенку долгосрочные образовательные преимущества и обучение на протяжении всей жизни. Двуязычное образование - это путь к двуязычию, которое является целью понимания второго или иностранного языка. Будучи преподавателем языка около десяти лет и обучая иностранному языку студентов из разных слоев общества, разных языков и уровней владения языком, автор приобрел богатый опыт. Весь накопленный опыт в дальнейшем помог склониться к различным взглядам на использование языка в образовании и преподавание языка в учебных заведениях. Было осознано, что знания, передаваемые с помощью двух языков, положительно влияют на учащегося и процесс обучения.In today's interconnected world, being bilingual makes anyone stand out of the crowd and lead the way. In many educational institutes in India, a bilingual education is an essential part of curriculum, it sets child up for long term educational benefits and a lifetime of learning. Bilingual education is the pathway to bilingualism, which is the goal of understanding a second or foreign language. Being language teacher for about ten years and teaching the foreign language to the students from various backgrounds, different vernaculars and levels of language proficiency has provided the author rich experience. All the experience gained further helped to incline on various perspectives regarding use of language in education and teaching language at educational institutions. It was realised that knowledge imparted through two languages positively influence the leaner and learning.48-5
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
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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