1,723,408 research outputs found
Farmer crop variety mixtures to cope with disease epidemics in the common bean cropping system of the Ecuadorian highlands
Get PDFAbstract 1. Common bean variety mixture diversity: a farmers and scientific view of its contribution to the highlands agroecosystem sustainability in Ecuador.
Common bean has been for long time the most cultivated legume for direct consumption in Ecuador. It is still cultivated mostly in traditional agroecosystems, in which farmers have implemented a series of management strategies to maintain crop sustainability. By linking participatory diagnosis, crop diversity assessment, and disease evaluation in the field, we established rationality of famers’ practices for the climbing common bean cropping system in the highlands of Ecuador. Climbing common bean is primarily grown intercropped with maize in a variety mixture strategy involving high genetic diversity. Two different types of variety mixtures are intercropped with maize in Cotacachi (north Ecuador): Chacra, a late maturing type of growth habit IV and Allpa an early maturing type of growth habit I, II, and III. In Saraguro (south Ecuador), only Chacra variety mixtures are cultivated; however, Popayán (Phaseolus coccineus) is often part of Chacra variety mixtures. Common bean cultivation in the intensified approach in Cotacachi and Saraguro aims food security by a better food provision of Chacra and Allpa types along the year, and by buffering biotic and abiotic constraints, which is achieved by planting genetically diverse variety mixtures. A negative association was observed between variety mixtures richness and evenness with rust epidemics. Farmers were knowledgeable about mixture diversity, mixture benefits, and pest and disease epidemics. They were able to name in an analytical way most components of variety mixtures, they perceived inter-specific diversity (intercrop) and intra-specific diversity (variety mixtures) reducing pest and diseases epidemics. Farmers also perceived evident differences among diseases, disease transmission, and disease resistance and its durability. However, as expected and reported frequently in literature, farmers associated disease origin with disease conducive conditions such as rain and clouds. Resistance and its durability are for farmers closely associated traits; resistant for farmers is absence of disease, which was easily detected in Phaseolus coccineus, which is a case of nonhost resistance or marginal host.Abstract 2. Resistance to Uromyces appendiculatus in common bean variety mixtures in the highland of Ecuador
Common bean in Ecuador is cultivated in a centre of crop diversity in an ancient agroecosystem, with high intraspecific diversity and traditional crop management strategies. In these conditions, the crop has adapted to important diseases such as rust (Uromyces appendiculatus), one of the most important constraints of common bean in Ecuador. To adapt the crop to biotic constraints, farmers have adopted variety mixtures as the key crop management strategy. In this study, we characterized resistance to rust operating in variety mixtures, for which 67 Cotacachi and 65 Saraguro lines were derived from variety mixtures. These lines were studied at the seedling stage with representative Ecuadorian isolates of U. appendiculatus, and were complementarily evaluated in field experiments in Cotacachi, Saraguro, and Gualaceo. At seedling stage, 31 different resistance genes were identified in Cotacachi and 38 were identified in Saraguro. The pathogen population has already adapted to these resistance factors and therefore they are not useful for conventional plant breeding. However, efficiency of resistance of these resistance factors varied significantly, suggesting that some of them are durable. In addition, resistance genes identified at the seedling stage significantly explained resistance in the field. Partial resistance (PR) also complementarily explained resistance in the field, especially for Cotacachi lines. Both, resistance genes and PR dynamically operating in a close relationship with U. appendiculatus evolution has created a high mixture effect that has reduced common bean vulnerability in the highlands of Ecuador.Abstract 3. Common bean variety mixture intensification: a sustainable and resilient approach to improve food security in the highlands of Ecuador.
Farmers in the highlands of Cotacachi-Ecuador have implemented variety mixture intensification to improve food security and sustain cultivation of common bean. The late-maturing Chacra belonging to growth habit IV and the early maturing Allpa belonging to growth habits I, II and III are planted together with maize in the same plot. The former type is planted with maize in the same planting site and the later type is planted between maize/Chacra plants. The effect of this intensification approach on pest and disease development, yield (kg/ha), and 100 seed weight were studied in Cotacachi (highland) and Tumbaco (valley). The land equivalent ratio (LER) index was used to establish the effect of the intensified approach on productivity (yield). In Cotacachi, LER of Chacra in any biotic constraint or climatic condition was higher than 0.5, being favoured in any condition by the intensification approach. Allpa on the other hand was slightly affected by the intensification approach at high rust and ALS epidemics, with a LER slightly lower than 0.5. Loss of Allpa due to disease epidemics was compensated by better performance of Chacra. In favourable conditions at low disease severity, LER of both Chacra and Allpa reached around 0.75, showing that Chacra and Allpa have co-adapted to the intensification approach. In Cotacachi, intensification was a compensatory system at high disease pressure, while a synergic system in favourable conditions. In Tumbaco, on the other hand the intensification approach was competitive, Chacra performed much better in the mixture than Allpa reaching a LER of around 1; however, Allpa performed better than Chacra as sole crop. Result of this study allowed us to conclude than Chacra is better adapted to the highland, while Allpa is better adapted to lowlands; and therefore, Allpa has been introduced to the highlands, and already co-adapted with Chacra, creating a compensatory and synergic system
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
R. Dingwall, J. Eekelaar, T. Murray, The Protection of Children. State Intervention and Family Life
No full textR. Dingwall, J. Eekelaar, T. Murray, The Protection of Children. State Intervention and Family Life. In: Revue internationale de droit comparé. Vol. 36 N°4, Octobre-décembre 1984. pp. 870-871
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
Statement of Edward T. Murray
Get PDFThis transcript of statements by Common Pleas Clerk of Court, Edward T. Murray describes a July 1954 casual conversation with the Honorable Judge Blythin while he was in Court Room 1 (not in-session) amidst a few other local attorneys. They talked about the Sheppard murder that had recently occurred, but more importantly when he (Judge Blythin) went to pick up his mail from his box -- which was the main reason he was in Court Room 1 -- he made the remark that Sam Sheppard was as guilty as he was innocent. According to Mr. Murray, he (Judge Blythin) said it in that Welsh brogue of his, and I have never forgotten that remark that he made.
Along with this descriptive remark, the Prosecuting and Sheppard Counsel Attorneys present asked Mr. Murray a few detail questions about the date and who the other attorneys were in Court Room 1 when Judge Blythin made his remarks. Mr. Murray was confident about the summer month of July and he could only recall one attorney\u27s name, Mr. Emmett Mayer, Esq
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