1,720,966 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
EFFECT OF LOW LEVEL OF OZONE ON GROWTH AND DEVELOPMENT OF BOTRYTIS ACLADA IN VITRO
No full textPenyakit pasca panen yang disebabkan oleh mikroba menyebabkan kerugian yang sangat besar setiap tahunnya. Pada pertanian konvensional, fungisida sudah digunakan selama bertahun-tahun untuk mengendalikan patogen pada tanaman. Sebagaimana telah diketahui, penggunaan bahan kimia secara terus menerus dapat berdampak buruk terhadap lingkungan dan menyebabkan resistensi. Ozon telah dianjurkan oleh para ahli sebagai alternatif pengendalian penggunaan bahan sintetik pada pengawetan bahan makanan karena ozon tidak meninggalkan residu pada bahan simpanan sehingga lebih aman untuk dikonsumsi. Penelitian ini bertujuan ini untuk mengetahui pengaruh ozon pada konsentrasi rendah (180 ppb) terhadap perkembangan koloni dan spora yang dihasilkan oleh Botrytis aclada secara in vitro. Dua tipe inokulum digunakan pada penelitian ini adalah miselia dan spora. Keduanya merupakan penyebab kerusakan pada bahan simpanan. Jamur yang diuji disimpan di dalam kotak yang dialiri ozon dengan suhu 7-8oC selama 14 hari. Pengamatan terhadap perkembangan koloni dilakukan dengan mengukur diameter koloni, sementara spora yang dihasilkan diamati pada hari ke 14 masa inkubasi. Hasil penelitian menunjukkan bahwa pemaparan ozon pada konsentrasi 180 ppb selama 14 hari tidak menurunkan perkembangan koloni B. aclada, tetapi efektif mengurangi jumlah spora yang dihasilkan
Pengaruh Campuran Kascing dengan Media Semai Tembakau (Nicotinia tabacum L.) Terhadap Penyakit Rebah Semai (Rhizoctonia solani KUHN.) di Rumah Kaca
No full textThe effect of Vermicompost and Tobacco Seedling Mixture on Damping-off (Rhizoctonia solani KUHN.) in Green HouseABSTRACT. This research objective was to determine the dosage of vermicompost that could suppres the disease intensity on tobacco (N. tabaccum). The experiment was carried out in the green house of the Department of Plant amd Disease, Faculty of Agriculture, Padjajaran University from July to August 2005. The experiment was arranged in the randomized completely block design using six treatment and four replications. The treatments were the mixture of seedling media and vermicompost at 1:1, 1:2, and 1:3, seedling media with propineb 70%, mixture of soil and bamboo leaf charcoal without vermicompost, and soil layered by bamboo leaf charcoal without vermicompost as control. The result showed that vermicompost mixed into tobacco seedling media could suppres the disease intensity. The dosage of the vermicompost at the ratio of 1:1, 1:2, and 1:3 suppressed 80,00%; 90,00%, and 92,50% of damping off disease intensity on tobacco respectively
The effect of silver nanoparticles on Trichoderma harzianum, Rhizoctonia spp., and fungal soil communities
Get PDFPhD ThesisSilver nanoparticles (AgNPs) have known anti-microbial properties and are applied in many
industrial applications ranging from medicine to fabric preservation. Recently, researchers have
proposed the use of AgNPs in agriculture to control plant pathogenic fungi. The use of AgNPs
to control plant pathogen fungi does raise concerns as they may potentially affect the activity
of beneficial soil microorganisms. In this work the effects of AgNPs on the plant pathogenic
fungus, Rhizoctonia spp., and their biocontrol agent, Trichoderma harzianum, and fungal soil
communities were investigated. The results showed that T. harzianum mycelium growth was
very tolerant to high levels of AgNPs (up to 600 mg L-1) while Rhizoctonia spp. were more
sensitive (mycelial growth was affected at 20 mg L-1). Nevertheless, AgNPs effect on
reproductive stage of T. harzianum, e.g. spore production, was not clear as it only showed on
one concentration. Despite the decrease in spore production of T. harzianum after AgNPs
exposure, the spores successfully germinated when cultivated on fresh growth medium (more
than 60%). Following up these findings, T. harzianum and AgNPs were combined to examine
the synergistic potential of these chemical and biological controls on growth of Rhizoctonia
spp. Interestingly, the combination of AgNPs and Trichoderma did not appear to act
synergistically to reduce Rhizoctonia growth in vitro. In subsequent work the effect of AgNPs
contamination on soil fungal communities was assessed by Illumina MiSeq Next Generation
Sequencing (NGS) and processed using the UPARSE pipeline run with USEARCH. The soil
contamination experiments were carried out over a period of 2 years as previous studies have
only examined effects of AgNPs contamination over a few months. Before analysing the
metabarcoding data from the Illumina sequencer, a method was developed to find a suitable
technique to process the data. It was found that single forward read sequences produced more
operational taxonomic unit (OTU) than single reverse and paired end sequences. Therefore,
single forward read sequences were used to investigate the effect of AgNPs on soil fungal
communities in this study. Soil contamination by AgNPs reduced fungal species richness,
evenness, and changed the community structure. For example, species such as Cryptococcus
terreus was the most abundant in controls but these were replaced by other species including
Trichocomaceae sp. in AgNPs contaminated soil. Tolerant species, such as T. spirale were
identified in highly contaminated soil (660 mg kg-1 of AgNPs) and this species has been found
in previous studies examining metal contamination. Overall the findings from this thesis
suggest that more intensive study will be required when considering AgNPs as an alternative
to synthetic fungicides to control plant pathogenic fungi as they have a negative impact on the
fungal community in soil even at lower levels e.g. 3 mg kg-1 of AgNPs.DIKTI (Ministry of Research, Technology and Higher
Education of the Republic of Indonesia) for their financial support, to Syiah Kuala University
for their administration suppor
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
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