1,721,029 research outputs found
The potential use of essential oils against mosquito larvae: A short review
No full textThe insecticidal activity of essential oils (EOs) on mosquito larvae has gained quite a lot of interest in recent scientific literature, and many articles envisage EOs as promising alternatives to conventional larvicides. However, the EOs described so far are not comparable in terms of efficacy with chemical or microbial larvicides. Moreover, for most EOs the low mammalian toxicity and the lack of environmental impacts have been claimed rather than tested. In industrialized countries, the availability of effective and environmental friendly microbial larvicides, will likely limit the EO-based products to very small market niches. Only in developing countries, where most aromatic plants are native, the full potential of botanical larvicides may be fully exploited. However, several research gaps remain to be filled before EOs could be considered as substitutes of conventional products
Toxicity and residual activity of spinetoram to neonate larvae of Grapholita molesta (Busck) and Cydia pomonella (L.) (Lepidoptera: Tortricidae): Semi-field and laboratory trials
No full textSpinetoram is a fermentation insecticide, derived from the actinomycete Saccharopolyspora spinosa. It works by disrupting the GABA-gated chloride channels and by causing persistent activation of insect nicotinic acetylcholine receptors. This study aimed to evaluate the efficacy of spinetoram for control of neonate larvae of both oriental fruit moth (OFM) Grapholita molesta (Busck) and codling moth (CM) Cydia pomonella (L.) in semi-field and laboratory trials. OFM and CM neonate larvae responded similarly to spinetoram, which showed high efficacy on both species. In semi-field experiments, regression analysis of the percentage of damaged fruits as a function of days after treatment showed a better performance of the highest spinetoram dose (10 g a.i./hl) in comparison with the maximum recommended field dose of the reference product emamectin benzoate (2.85 g a.i./hl). Surface-treated diet assays revealed LC50 values of 6.59 and 8.44 ng a.i./cm2 for neonate larvae of OFM and CM larvae, respectively. High percentages of mortality were recorded on both species after 24-h exposure to treated diet. For these reasons spinetoram could be considered a valuable tool in IPM strategies for OFM and CM control
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
Long term changes in the communities of native ladybirds in Northern Italy: impact of the invasive species Harmonia axyridis (Pallas)
No full textSince the mid-2000s, the exotic coccinellid species Harmonia axyridis (Pallas) has established itself in Northern Italy, raising serious concerns about possible repercussions on native ladybirds. In this study we compared the ladybird assemblages in 2015–2016 with those sampled in 1995–1996, before the arrival of H. axyridis. Surveys were carried out in the same sites and with the same methods for both periods. Aphidophagous ladybirds were sampled in hedgerows and herbaceous habitats at field margins by mechanical knockdown and sweeping net, respectively. The changes in the structure of ladybird communities after the arrival of H. axyridis were significantly different between arboreal and herbaceous habitats. Harmonia axyridis is currently the dominant species in shrubs and trees, and all the native ladybird species taken together account for only approximately one third of the total individuals sampled in 2015–2016. On the other hand, the relative abundance of the exotic species in herbaceous habitats was low, and it has had a negligible relevance on the structure of ladybird communities on grasslands. Among native species, Adalia bipunctata (L.), whose ecological niche largely overlaps with that of H. axyridis, suffered the largest decline between 1995–1996 and 2015–2016. The co-occurrence of H. axyridis invasion and the regression of A. bipunctata suggest a direct impact of the exotic species, because no other major modifications occurred in the studied areas between sampling periods
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
Compatibility of Beauveria bassiana with fungicides in vitro and on zucchini plants infested with Trialeurodes vaporariorum
No full textThe effect of fungicides on the entomopathogenic fungus Beauveria bassiana strain ATCC 74040 (Naturalis®) was evaluated in vitro and in vivo. The formulated fungicides Cantus® (boscalid), Frupica (mepanipyrim), Galben (benalaxyl), Melody® Compact (iprovalicarb + Cu oxychloride), Oracle⢠(fenamidone + Cu), Prosper® 300 CS (spiroxamine), Signum® (boscalid + pyraclostrobin), Switch® (cyprodinil + fludioxonil) and Talendo® (proquinazid) were tested on fungal colony growth from 10 field dose (10FD) to 10â4 FD. Each product mixed with Naturalis at FD was also tested against Trialeurodes vaporariorum on zucchini plants. Fungal colony growth was not affected by Cantus, Galben, Melody Compact, Oracle and Talendo at FD, while Frupica and Prosper 300 CS reduced colony growth by 9.7% and 6.9%, respectively. All these products did not inhibit the activity of B. bassiana on whiteflies at FD. On the contrary, Signum and Switch significantly inhibited colony growth at all doses and reduced the entomopathogenic activity on whiteflies when applied in mixture with B. bassiana. The toxic effect of both fungicides on B. bassiana persisted for 10 days after treatments, with a 91.2% reduction in nymph mortality in comparison to control for Signum and 87.4% for Switch. The mode of action of their active ingredients, boscalid, pyraclostrobin, cyprodinil and fludioxonil, individually and in mixture (boscalid + pyraclostrobin and cyprodinil + fludioxonil), was studied on fungal colony growth, spore germination, germ tube elongation and spore survival from 10FD to 10â2 FD. All these parameters were reduced by the four active ingredients at all doses, pyraclostrobin and fludioxonil completely inhibited spore germination, fludioxonil alone and in mixture with cyprodinil also inhibited completely spore survival
- …
