1,723,146 research outputs found
Pseudoperonospora cubensis development under differentiated nitrogen and potassium fertilization of Cucumis sativus
Full text linkCucumber (Cucumis sativus) is one of the most economically important vegetable crops worldwide and downy mildew caused by Pseudoperonospora cubensis is considered among the most destructive diseases that attack this plant. Although the effect of mineral nutrition on plant diseases for various crops has been studied, there is practically none on cucumbers. The overall objective of this study were (a) to investigate the effect of increasing inoculum concentrations of P. cubensis on downy mildew emergence on different aged cucumber leaves (b) to examine the effect of various N and K concentrations in the fertilization solution on the disease development and the leaf surface (c) to study the potential interaction of these two essential nutrients in relation with the application of a fungicide used for downy mildew control (d) to determine the disease progress with time (e) to investigate the nutritional status of cucumber tissues and substrate. A range of greenhouse experiments were conducted.
Cucumbers were grown under six K (200, 300, 400, 500, 600, 700 ppm) and six N (100, 200, 300, 400, 500 and 600 ppm) fertilization regimes, in two randomized block experiments respectively. Two factorial designs, one with three levels of spore concentrations and two leaf ages and the other with two N and three K levels plus fungicide treatments were also established. Cucumber plants (Cucumis sativus L. cv. Knossou) susceptible to downy mildew were artificially inoculated with P. cubensis. Disease was digitally assessed.
Statistical analysis of the obtained data indicated that the pathogen attacked leaves regardless of age. The lesion area was significantly increased with increasing spore content at low disease pressure. N concentration of 300 ppm had a positive effect on the leaf area when compared with the lower N rates. A concentration of 400 ppm K resulted in a marked increase in leaf area in relation to the other treatments although the differences were not statistically significant (P=0.05). There were indications that downy mildew was significantly decreased on the plants grown in 300 ppm N, 300 and 400 ppm K. However, N and K interaction was observed for leaf and lesion area. Thus, inhibition of infection was recorded with increasing K levels only at low N rates. The best combination for disease limitation was 200 ppm N and 400ppm K, which was found to be comparable with the fungicide used. The disease progress for downy mildew followed a cubic curve in all cases (N and K fertilization treatments, fungicide application). The importance of leaf and soil nutrient status on infection and leaf area index was also noted
Psychometric properties of the Patient Health Questionnaire nine-item version (PHQ-9) for use among hospitalized non-psychiatric medical patients
No full textBackground: Depression comorbid with non-psychiatric illness is widely prevalent, and the source of considerable burden. Reliable rating tools to detect depression in the general medical setting are therefore needed across different regions, including Argentina. The present study aimed to compare the psychometric characteristics of the Patient Health Questionnaire 9 (PHQ-9), Beck Depression Inventory-II (BDI-II) and Hospital Anxiety and Depression Scale (HADS) against each other, using independent criterion for the diagnosis of a major depressive episode (MDE).Methods: A multicenter, cross-sectional study was conducted over six months, screening 257 hospitalized general medical patients across three hospitals. After admission, participants were interviewed by a trained psychiatrist using the Mini International Neuropsychiatric Interview (MINI), and then each participant went through the administration of PHQ-9, BDI-II, and HADS.Results: For the diagnosis of a MDE according to the MINI, the best cut-off scores were 10 for the PHQ-9, 16 for the BDI-II, and 15 for the HADS. Owing to clinical interpretability issues, a two-factor solution was preferred using exploratory factor analysis (component 1 ?somatic/neurovegetative?, and component 2 ?psychological/cognitive? of depression). The local version of the PHQ-9 had high internal consistency (Cronbach's alpha=.87). Conclusions: The Argentine version of the PHQ-9 questionnaire showed acceptable validity and reliability for the screening of depressive symptoms.Fil: Daray, Federico Manuel. Universidad de Buenos Aires. Facultad de Medicina; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay; ArgentinaFil: Hunter, F.. Gobierno de la Ciudad de Buenos Aires. Hospital General de Agudos "Ramos Mejía"; ArgentinaFil: Anastasia, A.. National Institue for Social Security; ItaliaFil: Fornaro, M.. Università degli Studi di Napoli Federico II; Itali
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
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
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