1,720,973 research outputs found
Application of a chemical fractionation procedure for the characterization of leaf deposited PM
No full textFood waste materials appear efficient and low-cost adsorbents for the removal of organic and inorganic pollutants from wastewater
Full text linkIn recent studies, the adsorption capacity of several food waste materials has been assessed by performing adsorption experiments in heterogeneous operating conditions. In a latest study, the efficiency of such food waste materials for the removal of metals and metalloids from complex multi-element solutions was evaluated in homogeneous experimental conditions, which allowed comparing the adsorption capacities of the individual adsorbents. Considering the high efficiency of the examined low-cost adsorbents for the removal of inorganic pollutants, preliminary studies were conducted in our lab for assessing the potential of the investigated food waste materials to adsorb volatile organic compounds from a real polluted matrix of leachate. Some recent studies have shown the efficiency of low cost materials for the removal of industrial organic dyes, polycyclic aromatic hydrocarbons and phenolic compounds. However, the food waste adsorbents’ efficiency for the removal of volatile organic compounds was not investigated. Our preliminary studies showed good adsorption capacities of the examined food waste materials for aliphatic and aromatic hydrocarbons. Therefore, it is worth to carry out further studies about volatile organic compounds’ removal by food waste adsorbents
Spatial mapping of element concentrations in PM10: A powerful tool to identify spatial relationships between emission sources and oxidative potential of PM
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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
Effetti del lockdown sulla composizione e sulle sorgenti del PM10 nell'area di Roma attraverso source apportionment basato sul frazionamento chimico degli elementi
No full textDurante il lockdown del 2020, sono stati raccolti campioni giornalieri di PM10 in tre siti nell'area di Roma, due siti urbani da traffico (Sapienza e Via Saredo) e uno peri-urbano fortemente impattato da riscaldamento domestico a biomasse (Montelibretti). Il PM10 è stato campionato anche nei periodi precedenti e successivi al lockdown ed è stato analizzato per i macro-elementi, ioni inorganici, EC, OC, levoglucosano ed elementi in traccia. Questi ultimi sono stati frazionati chimicamente per aumentarne la selettività come traccianti di sorgente. I data-set ottenuti sono stati analizzati tramite PMF e sono state identificate sorgenti remote (due diversi contributi di polveri minerali, spray marino fresco, combustione di oli pesanti) e sorgenti locali (traffico veicolare e combustione di biomasse) che sono state fortemente abbattute durante il lockdown. Ciò ha permesso di descrivere chiaramente i profili delle sorgenti remote e di quantificare la riduzione dell'impatto delle fonti antropiche, consentendo di valutare l'efficacia delle misure di mitigazione generalmente adottate per controllare la concentrazione di massa del PM10
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
Urban trees for biomonitoring atmospheric particulate matter: An integrated approach combining plant functional traits, magnetic and chemical properties
No full textIncreased attention has been given to particulate matter (PM) that, as well as worsening air quality, is responsible for chronic and acute respiratory or cardiovascular diseases. Currently, most of the studies are focused on the capacity of plants and other biological media to adsorb PM, whereas few works explore the functional damage due to PM on urban vegetation. The present study, considering Quercus ilex L. as target species for its wide distribution in the Mediterranean urban and natural areas, pointed out that PM accumulation, inferred from magnetic and chemical properties, has almost no effects on structural morpho-functional traits as Relative Water Content or Specific Leaf Area but can impair processes related to the first photochemical reactions suggesting shading effect on leaves. PSI functionality and thus, carbon assimilation related processes, are impaired to a lesser extent by the oxidative potential of PM. Our results showed that, although several oxidative stressors can simultaneously affect morpho-functional traits, the interdisciplinary approach tested here can be a key tool to enlarge the spatial scale of biomonitoring activities as much as possible, and highlight a functional indicator of PM injury. This is needed to enhance the knowledge about the complex processes that are implied in the dynamic relationship between air quality, vegetation functionality and ecosystem services provisioning in urban areas
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
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