1,720,966 research outputs found
Post-harvest decontamination of rocket leaves through plasma activated water (PAW): effects on quality and shelf-life
No full textReady-to-eat vegetables offer great advantages to consumers due to their nutritional value and convenience, although they are an ideal substrate for microbial growth. Rocket (E. sativa) is appreciated by consumers for its pleasant bitter flavor and its high content of vitamins C and K, Calcium, fibers and glucosinolates. The major post-harvest problems of rocket are wilting, senescence and microbial spoilage which limits its shelf-life. Also decontamination from pathogenic microorganisms is a critical aspect for food safety. In the food industry, fresh rocket is usually washed with chlorine sanitizers (e.g. NaOCl, ClO2) to limit degradative processes and the microbial growth. However, this procedure releases on the rocket leaves several by-products including chloramines which are potentially harmful to human health. Plasma Activated Water (PAW), obtained by exposing water to cold plasma discharges, could be an alternative method for the decontamination of fresh rocket. In this contest, the aim of this study was to use PAW for the decontamination of fresh rocket leaves to extend their shelf-life without affecting their quality characteristics. PAW was generated with distilled water exposed to a Microsecond Pulsed Corona device for 4 minutes. Subsequently, rocket leaves were washed with PAW for 2, 5, 10 and 20 min then dried and finally stored at 4°C up to 10 days in PP bags under ordinary atmosphere. The load of spoilage microbiota on rocket salad treated with PAW was compared to those washed with sodium hypochlorite solution (100 ppm). Also, the effects of PAW washing on product quality traits were evaluated by measuring pH, color parameters and the content of some bioactive compounds. Data showed that PAW resulted in an immediate reduction of 1-1.5 log CFU/g for the target microbial groups. Sodium hypochlorite, which is the reference sanitizer, exhibited a similar efficacy to the PAW against mesophilic and psychrotrophic bacteria, while its activity against Enterobacteriaceae was higher than PAW. During storage at 4°C, cell loads of the spoilage microbiota increased suggesting that survivors were able to repair Second International Conference on Advances in Plasma Science and Technology (ICAPST), 2021, Coimbatore, India ISBN 978-93-90853-30-4 | ICAPST’21| 69 damages. However, the same trend was detected also for rocket samples washed with sodium hypochlorite. Moreover, minimal variations in the qualitative parameters were observed. Overall, these results showed that PAW can be a promising innovative post harvest treatment to preserve perishable foods such as ready to eat vegetables. The present work is part of the research activities developed within the project “PLASMAFOOD - Study and optimization of cold atmospheric plasma treatment for food safety and quality improvement” founded by MIUR - Ministero dell’Istruzione dell’Università e della Ricerca – PRIN Progetti di Ricerca di Rilevante Interesse Nazionale, Bando 2017
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
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
Cold Atmospheric Pressure Argon Plasma Jet Assisted Degradation of Malachite Green (MG) Aqueous Solution
Get PDFThe oxidative degradation of cold atmospheric pressure plasma assisted degradation of malachite Green (MG) was investigated in this study. Cold atmospheric pressure plasma assisted MG degradation process was carried out as a function various plasma treatment time (05, 10, and 15 mins). The % of degradation and presence carbon content in the plasma treated MG was examined by UV-Visible spectroscopy (UV-Vis) and total organic carbon (TOC) analyzer. Optical emission spectrometer was used to identify formation of various reactive species during in situ plasma treatment. The higher degradation percentage of 90% was obtained after plasma treatment time of 15 min and value of TOC also found to decreased significantly with increasing plasma treatment time. Toxicity of the plasma-treated MG aqueous solution samples was also examined by Staphylococcus aureus (S.aureus) bacteria
Influence of Transferred Arc Plasma Melting Time on the Formation of Phase and Microstructure of Mullite-Zirconia Composite
Get PDFTransferred arc plasma is an effective and simple technique to synthesis a high temperature reaction ceramic composite material. In this paper, 20 kW transferred arc plasma torch was used to synthesis mullite-zirconia composites through the solid-state reaction of 3:2 mole ratio of ball milled alumina and zircon powders. Dissociation of zircon in a thermal plasma arc is utilized as to prepare mullite-zirconia composites. The ball milled samples are melted for 3, 6, 9 and 12 minutes in transferred arc plasma torch at 20 kW power level with 10 lpm of argon flow rate and cooled by air. The phase and microstructure of melted samples were determined from X-ray diffraction (XRD) and SEM images. The obtained results shows that the processing time significantly influence on the formation of phase and microstructure of the mullite- zirconia composite
- …
