Potentially toxic elements speciation in bottom ashes from a municipal solid waste incinerator: A combined SEM-EDS, µ-XRF and µ-XANES study

Bottom Ashes from Municipal Solid Waste Incinerators and Waste to Energy plants represent an interesting source of secondary raw materials for many applications, like urban mining and inclusion in concrete, and road pavement. However, Bottom Ashes may contain potentially toxic elements, whose actual toxicity depends essentially on their oxidation state and mineralogical environment. For this reason, a representative sample of bottom ashes from Parma Waste to Energy plant has been selected to investigate the chemical speciation of Cr, Ni, Pb, Co, Zn and Cu by means of complementary techniques: Scanning Electron Microscopy with Energy Dispersive X-Ray Spectroscopy (SEM-EDS), micro X-Ray Fluorescence (µ-XRF) mapping and X-Ray Absorption Near Edge Structure (XANES) measurements by synchrotron radiation. This multi-technique approach allowed to obtain a general image of the mineralogical and chemical environment in which these elements are found. SEM-EDS analyses show the presence of Zn and Pb both in minerals and in glass matrix. Cr has been detected in the form of oxide and in spinel structure (chromite) whereas Co and Cu are found as alloy or metal inclusions. µ-XRF mapping reveals that Cu, Ni and Cr are generally associated to Na, K and Si suggesting their presence in glass matrix. XANES investigations exhibit that Cu has a variable oxidation state that suggesting its presence in the form of oxide, hydroxide, acetate and metal. Zn is mainly found as +II and in a number of different phases (including Zn-carbonates, in agreement with SEM-EDS data). Cr has been found only as +III, with XANES features resembling those of chromite, whereas as +VI was never identified. Ni and Co were found either as metal form and oxides. Pb spectra show a good match with oxides

Particle size and potential toxic element speciation in municipal solid waste incineration (Mswi) bottom ash

The speciation of potentially toxic elements (PTE) in bottom ashes from municipal solid waste incineration (MSWI) and their relationship with grain size is investigated. The proposed enrichment of several potential toxic elements in lower sized grains is discussed, comparing the literature and new data on Parma’s waste incinerator. Results from X-ray fluorescence spectrometry (XRF), SEM-EDS, and XRD analyses on different grain size show (1) a positive Si-trend, correlated with grain size and few lithophile elements, such as Zr and Rb. In Parma, Al, K, Mg, and Fe also correlate with Si for the portion below 2 mm; (2) a Ca-trend, with a strong negative correlation with Si and a positive correlation with loss on ignition (LOI), S, Cl, Ti, Zn, Pb, and Sn. Mineralogical composition shows a little change in grain size, as in previous investigations, but with substantial differences in amorphous content. SEM-EDS analysis shows that the amorphous portion is highly heterogeneous, with portions coming from melting during incineration, residual glass, and unburnt loss on ignition (LOI). The above results show that PTE elements are either present as metals (such as Cu and Ni, or Zn, Pb and Sn) in carbonate, sulfate, and amorphous residual LOI portions

Tiered architecture for remote access to data sources

Teamwork is benefited by the use of shared data sources. Also, ever increasingly, organizational work depends on the activities of team members situated in different physical locations, including both employees who work from their homes and others who have been temporarily transferred to another place. Since, for all these reasons, accessing data remotely is a growing need, organizations implement internal systems in order to control shared data access according to user privileges. In this regard, the cost of resource transportation needed to generate communication must be considered. The main contribution of this paper is the extended reference layered architecture ICDFSCV (Interface Control and Distributed File Systems - Communication Versioning). It allows to build a solution that, facilitates documents download and the creation and concurrent modification by multiple users through versioning control.Facultad de Informátic

Long-term exposure to air pollution and COVID-19 incidence: a prospective study of residents in the city of Varese, Northern Italy

OBJECTIVES: To investigate the association between long-term exposure to airborne pollutants and the incidence of SARS-CoV-2 up to March 2021 in a prospective study of residents in Varese city. METHODS: Citizens of Varese aged 6518 years as of 31 December 2019 were linked by residential address to 2018 average annual exposure to outdoor concentrations of PM2.5, PM10, NO2, NO and ozone modelled using the Flexible Air quality Regional Model (FARM) chemical transport model. Citizens were further linked to regional datasets for COVID-19 case ascertainment (positive nasopharyngeal swab specimens) and to define age, sex, living in a residential care home, population density and comorbidities. We estimated rate ratios and additional numbers of cases per 1\u2009\ub5g/m3 increase in air pollutants from single- and bi-pollutant Poisson regression models. RESULTS: The 62 848 residents generated 4408 cases. Yearly average PM2.5 exposure was 12.5\u2009\ub5g/m3. Age, living in a residential care home, history of stroke and medications for diabetes, hypertension and obstructive airway diseases were independently associated with COVID-19. In single-pollutant multivariate models, PM2.5 was associated with a 5.1% increase in the rate of COVID-19 (95%\u2009CI 2.7% to 7.5%), corresponding to 294 additional cases per 100 000 person-years. The association was confirmed in bi-pollutant models; excluding subjects in residential care homes; and further adjusting for area-based indicators of socioeconomic level and use of public transportation. Similar findings were observed for PM10, NO2 and NO. Ozone was associated with a 2% decrease in disease rate, the association being reversed in bi-pollutant models. CONCLUSIONS: Long-term exposure to low levels of air pollutants, especially PM2.5, increased the incidence of COVID-19. The causality warrants confirmation in future studies; meanwhile, government efforts to further reduce air pollution should continue

"Ser o no ser... cortés" : Papel de la cortesía en la interacción piloto/controlador

La aviación, como otros marcos institucionales, presenta un discurso propio (Drew y Sorjonen 2000) en el que los participantes están orientados hacia un objetivo institucional (Drew y Heritage 1992). La planificación lingüística existente para los hablantes pilotos y controladores aéreos (P/C) establece una norma profesional de comunicación cuyos criterios generales son la brevedad y la claridad (de- Matteis 2004). La vigencia de estos criterios hace poco deseable la manifestación de los fenómenos corteses pues estos aumentan la ocupación de las frecuencias de radio. Así, podemos considerar que existe un conflicto entre las pautas comunicativas de los hablantes como miembros de la comunidad lingüística del español bonaerense y las que deben seguir en tanto miembros de la institución. Nuestro propósito es analizar los usos corteses que efectivamente se registran en la interacción P/C en la región de español bonaerense a la luz de los últimos enfoques sobre los estudios de la cortesía (Escandell Vidal 1995; Bravo 2003), tomando como marcos teóricos generales la sociolingüística interaccional (Gumperz 1982a, 1982b; Tannen 1985, 1992) y el análisis del discurso (Stubbs 1983; Drew y Sorjonen 2000). La metodología de trabajo consiste en la transcripción y análisis de un corpus de grabaciones de comunicaciones P/C realizadas mediante la técnica participante-observador (Labov 1970) en la torre de control del aeropuerto de Bahía Blanca. En forma complementaria, contamos con datos obtenidos a través de la realización de entrevistas a hablantes pilotos comerciales que fueron entrevistados y a controladores aéreos que fueron encuestados en relación con el tema de la cortesía en sus comunicaciones.Facultad de Humanidades y Ciencias de la Educació

Metaphor and lexical neology: productivity of the {-nauta} morpheme in Spanish

This paper proposes a relationship between the productivity of the {-nauta} morpheme in Spanish and a series of metaphors that have, recursively, expanded their scope. The analysis takes under consideration studies addressing the processes of word formation from a perspective of diachronic morphology (Rainer 2002; Pharies 2002, 2004), as well as the contribution to the study of neologisms of studies that highlight the relevance of metaphor in the organization of thought and everyday communication (Lakoff and Johnson 1980) and allow to address them in relation to social representations (Rodríguez Salazar, 2007). All sources are written texts representing different varieties of Spanish, with special attention to the peninsular and argentine varieties. Online searches were used to identify examples of particular words and lexicographical works (DRAE, DEA, DUE, DVUA, VOX and those integrating the Nuevo Tesoro Lexicográfico de la Lengua Española [online]) are also considered as secondary sources

Colorimetric paper-based device for hazardous compounds detection in air and water: A proof of concept

In the last decades, the increase in global industrialization and the consequent technological progress have damaged the quality of the environment. As a consequence, the high levels of hazardous compounds such as metals and gases released in the atmosphere and water, have raised several concerns about the health of living organisms. Today, many analytical techniques are available with the aim to detect pollutant chemical species. However, a lot of them are not affordable due to the expensive instrumentations, time-consuming processes and high reagents volumes. Last but not least, their use is exclusive to trained operators. Contrarily, colorimetric sensing devices, including paper-based devices, are easy to use, providing results in a short time, without particular specializations to interpret the results. In addition, the colorimetric response is suitable for fast detection, especially in resource-limited environments or underdeveloped countries. Among different chemical species, transition and heavy metals such as iron Fe(II) and copper Cu(II) as well as volatile compounds, such as ammonia (NH3) and acetaldehyde (C2 H4 O) are widespread mainly in industrialized geographical areas. In this work, we developed a colorimetric paper-based analytical device (PAD) to detect different contaminants, including Fe2+ and Cu2+ ions in water, and NH3 and C2 H4 O in air at low concentrations. This study is a “proof of concept” of a new paper sensor in which the intensity of the colorimetric response is proportional to the concentration of a detected pollutant species. The sensor model could be further implemented in other technologies, such as drones, individual protection devices or wearable apparatus to monitor the exposure to toxic species in both indoor and outdoor environments

Frequency of personal pronouns and verbal endings as linguistic indicator of interactional tension in institutional discourse

Integrating theoretical and methodological contributions from institutional discourse analysis and interactional sociolinguistics, we attempt to prove that the tasks and institutional identities determine the way pilots and air traffic controllers(P/C dyad) manage instances of negotiation, disagreement and, above all, interactional conflict. Based on data from interactions registered by observation-participant in Argentina, and also resorting to online resources that allow to expand the sample to other varieties of Spanish, the role of institutional constraints upon these non-standardized instances of the P/C interactional dynamic is corroborated. It is concluded that, given the limitations imposed by the highly regulated and standardized features of this institutional discourse, the explicit and emphatic signaling of persons in the discourse is a strategy that is preferred to manage and identify interactional tensions in this socio-technical field. </p