1,721,011 research outputs found
Evaluation of the effects of PM emitted by specific emission sources on environment and health
Full text linkThe health burden due to particulate matter (PM) air pollution (PM10 and PM2.5) is one of the biggest
environmental health concerns in the WHO European Region and around the world.
A particular challenge in this research field is about the identification of the physical and chemical
characteristics of PM able to reveal the correlation that links fine particle pollutants and respiratory
morbidity and mortality.
PM is a complex, heterogeneous mixture, whose chemical and physical characteristics (particle size
distribution, chemical composition) changes in time and space and depends on various factors
(sources, atmospheric chemistry and weather conditions). In literature, most studies associate PM
emitted by the major combustion sources, mobile and stationary, with a range of serious health
effects, including increased morbidity and mortality from cardiovascular and respiratory conditions.
Current knowledge, however, does not allow a quantification of the health effects of PM emissions
from different sources or from individual PM components. Therefore, the study of a depth chemical
characterization of the individual emissive sources would be helpful in identification of possible PM
toxic effects. Another important factor in the assessment of the aspects that link the human health to
particulate pollution is the size of the particle to which the population is exposed. In fact, the size of
the particles, together with their chemical composition, are fundamental indicator of health risk.
Particle size determines in which region of the respiratory tract particles are deposited, as well as the
amount of particles deposited. In this optic, a better understanding of the strength of individual
emission sources, of the size of the emitted particles and of their chemical composition could facilitate
the design of targeted abatement policies more effective to reduce the burden of diseases due to air
pollution. My PhD work was carried out in response to all the above-mentioned needs. In fact, during
these three years, I have been studying and deepened all those factors (size, emission sources,
chemical composition and indicators of oxidative stress) that could be crucial, to the scientific world,
for a better understanding of the PM's harmful effects both on humans and on environment.
I have been involved in the study of possible techniques able to monitor and characterize as well as
possible, the different emission sources, some of which can only be identified by using high timeresolved
methods. I have been also involved in the study of different methods that can quantify the
capacity of inhaled PM to cause oxidative stress within the lung, which seems to be one of the main
mechanisms for the adverse cardio-respiratory health effects observed in epidemiological studies
Glass ceramics for high-temperature sealing applications: synthesis and physicochemical properties of modified CaO-MgO-Al2O3-SiO2 materials, with a view to recycling of industrial waste
Full text linkSolid Oxide Fuel cells (SOFC) and dense gas separation membranes based on mixed ionic and electronic conductors have gained increased interest the resent years due the search for new technologies for clean energy generation. These technologies can be utilized to produce electricity from fossil fuel with low CO2 emission compared to conventional gas or coal based energy plants. One crucial challenge with SOFCs is the sealing of the active membranes/electrolytes to prevent leakage of air to fuel side or vice versa. Due to the high operating temperatures of typical 600-1000°C the selection of reliable sealing materials is limited. The seals have to remain gas tight during the life time of the reactor/SOFC, they need to be chemical compatible with the sealed materials and stable in reducing and oxidizing atmospheres containing water vapor and CO2, and finally they should be cheap, readily available and easy to process. The main purpose of the present work was to evaluate rigid bonded glass ceramic seals for dense oxygen ion and proton conducting membranes and electrolytes for SOFCs. First, a review of sealing technologies has been carried out with emphasis on SOFC and ceramic membranes technologies applicable for zero emission power plants. Regarding sealing, the best and cheapest materials at the present time are based on silicate glass and glass ceramics.
The aim is to provide a systematic study of the properties of glasses and glass-ceramics as a function of the glass composition in the CaO-MgO-Al2O3-SiO2 system, which represent the most advanced sealing technology for high-temperature Solid Oxide Fuel Cells (SOFC).
Two glass systems have been evaluated, aluminosilicate and boroaluminosilicate and their variants obtained adding five different oxides acting as nucleating agents, like TiO2, MnO2, ZnO and SnO2. Fabrication and characterization of the glasses are reported with special focus on the thermal and thermochanical properties, glass forming ability, kinetic crystallization and phase evaluation. The influence of different additives in glass and glass ceramic properties has been analyze in depth.
In the last section, the research has been extended to the recycling of aluminosilicate basted waste to characterize a new type of glass ceramic derived from industrial waste, like Kaolin clay waste
Mental Health and COVID-19: An Action Plan
No full textSince January 2020, the disease caused by the SARS-CoV-2 virus has spread and become pandemic. In a few months, the virus had seriously affected the health systems of various countries of the world and placed people in difficult psychological conditions. This manuscript briefly reviews COVID-19’s studies focused on psychological reactions to the event. Furthermore, this work presents a plan to easily frame the priorities of mental health areas related to COVID-19 which should be disseminated and that should be known by all health professionals and also by the major administrators of public health to empower the actual situation and prevent future emergencies. Today psychological COVID-19’s sequelae affected a great number of people in the world and also called “Long COVID” presents
psychological symptoms that affect for a long time people diagnosed as COVID. Due to this experience, it seems advisable to rethink the organization of mental health services to better help the population in case of serious alert for life
Bipolar and related disorders induced by sodium 4-phenylbutyrate in a male adolescent with bile salt export pump deficiency disease
Full text linkBile Salt Export Pump (BSEP) Deficiency disease, including Progressive Familial Intrahepatic Cholestasis type 2 (PFIC2), is a rare disease, usually leading within the first ten years to portal hypertension, liver failure, hepatocellular carcinoma. Often liver transplantation is needed. Sodium 4-phenylbutyrate (4-PB) seems to be a potential therapeutic compound for PFIC2. Psychiatric side effects in the adolescent population are little known and little studied since the drug used to treat children and infants. So we described a case of Caucasian boy, suffering from a late onset PFIC2, listed for a liver transplant when he was sixteen and treated with 4-FB (200 mg per kilogram of body weight per day). The drug was discontinued for the onset of bipolar and related disorders. This case illustrates possible psychiatric side effects of the drug
Bipolar and related disorders induced by sodium 4-phenylbutyrate in a male adolescent with bile salt export pump deficiency disease
No full textBile Salt Export Pump (BSEP) Deficiency disease, including Progressive Familial Intrahepatic Cholestasis type 2 (PFIC2), is a rare disease, usually leading within the first ten years to portal hypertension, liver failure, hepatocellular carcinoma. Often liver transplantation is needed. Sodium 4-phenylbutyrate (4-PB) seems to be a potential therapeutic compound for PFIC2. Psychiatric side effects in the adolescent population are little known and little studied since the drug used to treat children and infants. So we described a case of Caucasian boy, suffering from a late onset PFIC2, listed for a liver transplant when he was sixteen and treated with 4-FB (200 mg per kilogram of body weight per day). The drug was discontinued for the onset of bipolar and related disorders. This case illustrates possible psychiatric side effects of the drug
Mass size distribution of particle-bound water
No full textThe thermal-ramp Karl-Fisher method (tr-KF) for the determination of PM-bound water has been applied
to size-segregated PM samples collected in areas subjected to different environmental conditions
(protracted atmospheric stability, desert dust intrusion, urban atmosphere). This method, based on the
use of a thermal ramp for the desorption of water from PM samples and the subsequent analysis by the
coulometric KF technique, had been previously shown to differentiate water contributes retained with
different strength and associated to different chemical components in the atmospheric aerosol.
The application of the method to size-segregated samples has revealed that water showed a typical
mass size distribution in each one of the three environmental situations that were taken into consideration. A very similar size distribution was shown by the chemical PM components that prevailed during
each event: ammonium nitrate in the case of atmospheric stability, crustal species in the case of desert
dust, road-dust components in the case of urban sites.
The shape of the tr-KF curve varied according to the size of the collected particles. Considering the size
ranges that better characterize the event (fine fraction for atmospheric stability, coarse fraction for dust
intrusion, bi-modal distribution for urban dust), this shape is coherent with the typical tr-KF shape
shown by water bound to the chemical species that predominate in the same PM size range (ammonium
nitrate, crustal species, secondary/combustion species - road dust components)
Oxidative potential of size-segregated PM in an urban and an industrial area of Italy
No full textThis work is focused on the relationship between the size distribution of some source tracers of atmospheric particulate matter (PM) and the oxidative potential (OP) of each PM size fraction. Size-segregated PM samples were collected by a multistage impactor (cut-sizes: 0.18, 0.32, 0.56, 1.0, 1.8, 3.2, 5.6, 10 and 18 μm) in two geographical areas of Italy (Rome and Ferrara), characterized by different strength of the main PM sources. The samples were analysed by three different acellular OP methods: dithiothreitol (DTT), dichlorofluorescein diacetate (DCFH) and ascorbate (AA) assay. Elemental (Li, Be, B, Na, Mg, Al, Si, P, K, Ca, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Ga, As, Se, Rb, Sr, Zr, Nb, Mo, Cd, Sn, Sb, Te, Cs, Ba, La, Ce, W, Tl, Pb, Bi and U) and ionic (Cl−, NO3−, SO42−, Na+, NH4+, K+, Mg2+, Ca2+) composition of the same samples was also determined, in order to trace the contribution of the main PM sources. The size distribution of the OP values was compared to the size distribution of some PM source tracers, with the aim of identifying the PM sources that mostly influence the oxidative properties of atmospheric dust. AA assay resulted to be more sensitive towards coarse particles and OPAA showed a size distribution very similar to that of brake dust tracers. DTT and DCFH assays resulted instead more sensitive towards fine particles. OPDTT and OPDCFH values were comparable at the two sites; sources whose strength was very different in the two monitored areas (secondary contribution and, to a less extent, industrial sources) did not then contribute significantly to the measured OP values. The dimensional behaviour of OPDTT and OPDCFH was consistent with the contribution of biomass burning. © 2018 Elsevier Lt
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
- …
