Search results for "USP"
showing 10 items of 1290 documents
Suspect, non-target and target screening of emerging pollutants using data independent acquisition: Assessment of a Mediterranean River basin
2019
A single workflow based on three approaches (target, suspected and non-target screening) using liquid chromatography coupled to quadrupole-time-of-flight mass spectrometry (LC-QTOF-MS) in data independent acquisition mode (DIA) was developed to assess the presence of emerging pollutants (EPs) in water and sediments from a Mediterranean River Basin. Identification of potential contaminants was based on mass accuracy, isotopic ratio pattern, theoretical fragmentation, and retention time using Waters UNIFI software. In the suspect screening against a library containing 2200 components, 68 contaminants were tentatively identified, 6 of which were confirmed and quantified with analytical standar…
Natural and anthropogenic sources of total suspended particulate and their contribution to the formation of black crusts on building stone materials …
2012
Blackening and disaggregation of exposed surfaces of stone monuments are well-known effects of stone decay taking place in polluted urban environments all over the world. This paper aims to assess the contribution of natural and anthropogenic sources of total suspended particulate (TSP) causing permanent damage (black crusts) to the stone monuments of Catania (Sicily), one of the most popular ‘‘cities of art’’ of southern Italy. Atmospheric pollution of Catania, a typical Mediterranean coastal town, is mainly contributed by vehicle exhaust emissions rather than industrial ones. Episodically, the city also suffers gaseous and ash emissions (plumes) from the nearby Mount Etna volcano. Thus, t…
Spatial and temporal changes of suspended matter in relation to wind and vegetation cover in a mediterranean shallow coastal environment
1999
Seasonal and spatial changes in seston, (POC), particulate organic carbon, (PON) particulate organic nitrogen and chlorophyll-a concentrations were studied on a monthly basis in a Mediterranean shallow coastal area (Stagnone di Marsala, Western Sicily) in order to gather information on factors controlling particulate organic matter distribution and composition. Seston concentration and composition were connected to the main physicochemical and biological driving factors, such as temperature, salinity, dissolved oxygen, wind-speed and biomass of submerged vegetation. The Stagnone di Marsala is characterized by high temperatures with strong seasonality (range: 11-28°C), while values ranged fr…
The growth of “black crusts” on calcareous building stones in Palermo (Sicily): a first appraisal of anthropogenic and natural sulphur sources
2008
Chemical, mineralogical and isotopic composition (34S/32S) analyses were carried out on “black crusts” developed on the old buildings of Palermo (Sicily) with the aim to distinguish between natural and anthropogenic sulphur sources. Furthermore individual samples of total suspended particulate (TSP) were collected and analysed in order to estimate the influence of air pollution on the decay process of calcareous stones in a typical southern Mediterranean coastal environment. SEM/EDS analysis, X-ray diffractometry, IR spectroscopy and liquid chromatography led to the compositional characterization of “black crusts” and airborne particulate matter in the city. Sulphur isotopic compositions of…
Can recreational scuba divers alter natural gross sedimentation rate? A case study from a Mediterranean deep cave
2010
Abstract Di Franco, A., Ferruzza, G., Baiata, P., Chemello, R., and Milazzo, M. 2010. Can recreational scuba divers alter natural gross sedimentation rate? A case study from a Mediterranean deep cave. – ICES Journal of Marine Science, 67: 871–874. Submarine caves are environments with features distinguishing them from other littoral habitats but, despite their ecological importance, their response to anthropogenic disturbance has been seldom verified. One potential threat affecting natural communities within caves is represented by recreational scuba diving. Divers' disturbance within marine caves is mainly related to physical contacts and increased sediment resuspension potentially affecti…
A Culturally Sensitive Approach to Promoting Initial Literacy Development in Africa : Ongoing and Planned Research and Development at the University …
2017
A four-year research and development program at CAPOLSA (the Centre for the Promotion of Literacy in Sub-Saharan Africa) was inspired by widespread dissatisfaction with poor literacy outcomes of mass basic schooling in Zambia and sought to test the generalizability of a scientifically grounded, computer-mediated instructional resource developed in Finland, for effective intervention in an African society where different linguistic and educational conditions obtain. Specific challenges and opportunities posed by the local sociocultural context included the prevalence of multilingualism, the relatively transparent orthographies of local languages, and poor infrastructure of the public school …
Heterogeneous Photocatalysis and Photoelectrocatalysis: From Unselective Abatement of Noxious Species to Selective Production of High-Value Chemicals
2015
Heterogeneous photocatalysis and photoelectrocatalysis have been considered as oxidation technologies to abate unselectively noxious species. This article focuses instead on the utilization of these methods for selective syntheses of organic molecules. Some promising reactions have been reported in the presence of various TiO2 samples and the important role played by the amorphous phase has been discussed. The low solubility of most of the organic compounds in water limits the utilization of photocatalysis. Dimethyl carbonate has been proposed as an alternative green organic solvent. The recovery of the products by coupling photocatalysis with pervaporation membrane technology seems to be a…
Non‐bacterial thrombotic endocarditis in a patient with pancreatic carcinoma
2021
Nonbacterial thrombotic endocarditis (NBTE) is a rare condition that most often accompanies a malignant disease and involves a hypercoagulable state. We report the incidental finding of a rare case of an NBTE affecting the tricuspid valve in a patient with metastatic pancreatic carcinoma complicated by severe venous and arterial thromboembolisms.
Force-induced diffusion in microrheology
2012
We investigate the force-induced diffusive motion of a tracer particle inside a glass-forming suspension when a strong external force is applied to the probe (active nonlinear microrheology). A schematic model of mode-coupling theory introduced recently is extended to describe the transient dynamics of the probe particle, and used to analyze recent molecular-dynamics simulation data. The model describes non-trivial transient displacements of the probe before a steady-state velocity is reached. The external force also induces diffusive motion in the direction perpendicular to its axis. We address the relation between the transverse diffusion coefficient D(perpendicular) and the force-depende…
Nonequilibrium depletion interactions in active microrheology.
2017
Entropic depletion forces arise between mesoscopic bodies that are immersed in a suspension of macromolecules, such as colloid-polymer mixtures. Here we consider the case of a driven colloidal probe in the presence of another, passive colloidal particle, both solvated in an ideal bath of small spherical particles. We calculate the nonequilibrium forces mediated by the depletants on the two colloidal particles within a dynamical superposition approximation (DSA) scheme. In order to assess the quality of this approximation, and to obtain the colloidal microstructure around the driven probe, we corroborate our theoretical results with Brownian dynamics simulations.