The Cyprus Institute

About: The Cyprus Institute is a other organization based out in Nicosia, Cyprus. It is known for research contribution in the topics: Aerosol & Environmental science. The organization has 418 authors who have published 1252 publications receiving 32586 citations.

Determination of the Δ ( 1232 ) axial and pseudoscalar form factors from lattice QCD

Abstract: We present a lattice QCD calculation of the $\ensuremath{\Delta}(1232)$ matrix elements of the axial-vector and pseudoscalar currents. The decomposition of these matrix elements into the appropriate Lorentz invariant form factors is carried out, and the techniques to calculate the form factors are developed and tested using quenched configurations. Results are obtained for $2+1$ domain wall fermions and within a hybrid scheme with domain wall valence and staggered sea quarks. Two Goldberger-Treiman--type relations connecting the axial to the pseudoscalar effective couplings are derived. These and further relations based on the pion-pole dominance hypothesis are examined using the lattice QCD results, finding support for their validity. Using lattice QCD results on the axial charges of the nucleon and the $\ensuremath{\Delta}$, as well as the nucleon-to-$\ensuremath{\Delta}$ transition coupling constant, we perform a combined chiral fit to all three quantities and study their pion mass dependence as the chiral limit is approached.

Biochemical biomarker responses to pollution in selected sentinel organisms across the Eastern Mediterranean and the Black Sea

Abstract: Pollution effects were assessed by means of biochemical biomarkers (catalase, glutathione S-transferase and acetylcholinesterase activities, and metallothioneins content) in five species at selected coastal sites across the Eastern Mediterranean and the Black Sea. The mussel Mytilus galloprovincialis, a well-established sentinel species, was investigated in the Adriatic Sea, Aegean Sea, and Black Sea. The mussel Brachidontes pharaonis and the striped red mullet Mullus surmuletus were used in the Levantine Sea where M. galloprovincialis is not present. The white seabream Diplodus sargus sargus and the gastropod Rapana venosa were additionally sampled in the Adriatic and the Black Sea, respectively. Mussels showed catalase, glutathione S-transferase, and acetylcholinesterase responses to pollution in most geographical areas while the response of metallothioneins was restricted to a few sites. R. venosa showed marked responses of catalase and metallothioneins whereas both fish species did not generally exhibit variations in biomarker values among sites. The approach based on the reference deviation concept using the "Integrated Biological Responses version 2" index was useful for the interpretation of overall biomarker responses.

Workplace Exposure to Nanoparticles during Thermal Spraying of Ceramic Coatings

Abstract: Thermal spraying is widely used for industrial-scale application of ceramic coatings onto metallic surfaces. The particular process has implications for occupational health, as the high energy process generates high emissions of metal-bearing nanoparticles. Emissions and their impact on exposure were characterized during thermal spraying in a work environment, by monitoring size-resolved number and mass concentrations, lung-deposited surface area, particle morphology, and chemical composition. Along with exposure quantification, the modal analysis of the emissions assisted in distinguishing particles from different sources, while an inhalation model provided evidence regarding the potential deposition of particulate matter on human respiratory system. High particle number (>10(6) cm-3; 30-40 nm) and mass (60-600 µgPM1 m-3) concentrations were recorded inside the spraying booths, which impacted exposure in the worker area (10(4)-10(5) cm-3, 40-65 nm; 44-87 µgPM1 m-3). Irregularly-shaped, metal-containing particles (Ni, Cr, W) were sampled from the worker area, as single particles and aggregates (5-200 nm). Energy dispersive X-ray analysis confirmed the presence of particles originated from the coating material, establishing a direct link between the spraying activity and exposure. In particle number count, 90% of the particles were between 26-90 nm. Inhaled dose rates, calculated from the exposure levels, resulted in particle number rates (n˙) between 353 × 10(6)-1024 × 10(6) min-1, with 70% of deposition occurring in the alveolar region. The effectiveness of personal protective equipment (FPP3 masks) was tested under real working conditions. The proper sealing of the spraying booths was identified as a key element for exposure reduction. This study provides high time-resolved aerosol data which may be valuable for validating indoor aerosol models applied to risk assessment.

Lung Antioxidant Depletion: A Predictive Indicator of Cellular Stress Induced by Ambient Fine Particles

Abstract: Regulations on ambient particulate matter (PM) are becoming more stringent because of adverse health effects arising from PM exposure. PM-induced oxidant production is a key mechanism behind the observed health effects and is heavily dependent on PM composition. Measurement of the intrinsic oxidative potential (OP) of PM could provide an integrated indicator of PM bioreactivity and could serve as a better metric of PM hazard exposure than PM mass concentration. The OP of two chemically contrasted PM2.5 samples was compared through four acellular assays, and OP predictive capability was evaluated in different cellular assays on two in vitro lung cell models. PM2.5 collected in Paris at a site close to the traffic exhibited a systematically higher OP in all assays compared to PM2.5 enriched in particles from domestic wood burning. Similar results were obtained for oxidative stress, expression of antioxidant enzymes, and pro-inflammatory chemokine in human bronchial epithelial and endothelial cells. The strongest correlations between OP assays and cellular responses were observed with the antioxidant (ascorbic acid and glutathione) depletion (OPAO) assay. Multivariate regression analysis from OP daily measurements suggested that OPAO was strongly correlated with polycyclic aromatic hydrocarbons at the traffic site while it was correlated with potassium for the domestic wood burning sample.