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In this paper, results from receptor modelling performed on a well-characterised PM 1 dataset were combined to chemical light extinction data (b ext ) with the aim of assessing the impact of different PM 1 components and sources on light extinction and visibility at a European polluted urban area. It is noteworthy that, at the state of the art, there are still very few papers estimating the impact of different emission sources on light extinction as we present here, although being among the major environmental challenges at many polluted areas. Following the concept of the well-known IMPROVE algorithm, here a tailored site-specific approach (recently developed by our group) was applied to assess chemical light extinction due to PM 1 components and major sources. PM 1 samples collected separately during daytime and nighttime at the urban area of Milan (Italy) were chemically characterised for elements, major ions, elemental and organic carbon, and levoglucosan. Chemical light extinction was estimated and results showed that at the investigated urban site it is heavily impacted by ammonium nitrate and organic matter. Receptor modelling (i.e. Positive Matrix Factorization, EPA-PMF 5.0) was effective to obtain source apportionment; the most reliable solution was found with 7 factors which were tentatively assigned to nitrates, sulphates, wood burning, traffic, industry, fine dust, and a Pb-rich source. The apportionment of aerosol light extinction (b ext,aer ) according to resolved sources showed that considering all samples together nitrate contributed at most (on average 41.6%), followed by sulphate, traffic, and wood burning accounting for 18.3%, 17.8% and 12.4%, respectively. [ABSTRACT FROM AUTHOR]

Estimates of light extinction and visibility are routinely performed by the U.S. Interagency Monitoring of Protected Visual Environments (IMPROVE) network using a simple algorithm which assesses light extinction coefficient (b ext ) at remote and rural sites from concentrations of major particulate matter (PM) species, NO 2 , and Rayleigh scattering from clear-air gaseous components. Following the same approach, in this paper an equation with tailored (i.e. site-specific) coefficients was implemented with the aim of reducing uncertainties and assumptions of the IMPROVE algorithm for applications at polluted urban sites. Major differences compared to IMPROVE algorithm are: 1) dry mass extinction efficiencies calculated using a discrete dipole approximation code with aerosol size distributions measured at our monitoring site as input data; 2) site-specific water growth functions computed separately for ammonium sulfate, ammonium nitrate, and organic matter; 3) fine soil evaluated using an equation previously adopted at our urban site; 4) aerosol absorption component assessed directly through filter-based optical measurements. Details about the calculations performed are reported in the paper and the comparison with the IMPROVE revised algorithm is discussed. The tailored approach here proposed to estimate reconstructed light extinction was applied to PM 2.5 test samples collected on purpose in Milan (Italy), where heavy pollution episodes occur during winter periods. In addition, visual range was calculated applying the Koschmieder equation and compared to visibility measured at the nearby Milano-Linate airport obtaining a fairly good correlation. [ABSTRACT FROM AUTHOR]

In this work, a comprehensive characterisation and source apportionment of size-segregated aerosol collected using a multistage cascade impactor was performed. The samples were collected during wintertime in Milan (Italy), which is located in the Po Valley, one of the main pollution hot-spot areas in Europe. For every sampling, size-segregated mass concentration, elemental and ionic composition, and levoglucosan concentration were determined. Size-segregated data were inverted using the program MICRON to identify and quantify modal contributions of all the measured components. The detailed chemical characterisation allowed the application of a three-way (3-D) receptor model (implemented using Multilinear Engine) for size-segregated source apportionment and chemical profiles identification. It is noteworthy that - as far as we know - this is the first time that three-way source apportionment is attempted using data of aerosol collected by traditional cascade impactors. Seven factors were identified: wood burning, industry, resuspended dust, regional aerosol, construction works, traffic 1, and traffic 2. Further insights into size-segregated factor profiles suggested that the traffic 1 factor can be associated to diesel vehicles and traffic 2 to gasoline vehicles. The regional aerosol factor resulted to be the main contributor (nearly 50%) to the droplet mode (accumulation sub-mode with modal diameter in the range 0.5–1 μm), whereas the overall contribution from the two factors related to traffic was the most important one in the other size modes (34–41%). The results showed that applying a 3-D receptor model to size-segregated samples allows identifying factors of local and regional origin while receptor modelling on integrated PM fractions usually singles out factors characterised by primary (e.g. industry, traffic, soil dust) and secondary (e.g. ammonium sulphate and nitrate) origin. Furthermore, the results suggested that the information on size-segregated chemical composition in different size classes was exploited by the model to relate primary emissions to rapidly-formed secondary compounds. [ABSTRACT FROM AUTHOR]

The effect of phosphine on Salmonella enterica serotype Enteritidis inoculated in culture medium and in black pepper grains (Piper nigrum), as well as on the reduction of the microbial load of the dried and moisturized product, was verified. The postfumigation effect was verified in inoculated samples with 0.92 and 0.97 water activity (aw) exposed to 6 g/m³ phosphine for 72 h, dried to 0.67 aw and stored for 24, 48, and 72 h. No decreases were observed in Salmonella Enteritidis populations in culture medium when fumigant concentrations up to 6 g/m³ were applied for 48 h at 35°C. However, the colonies showed reductions in size and atypical coloration as the phosphine concentration increased. No reduction in Salmonella counts occurred on the inoculated dried samples after fumigation. On the other hand, when phosphine at concentrations of 6 g/m³ was applied on moisturized black pepper for 72 h, decreases in Salmonella counts of around 80% were observed. The counts of total aerobic mesophilic bacterium populations of the dried and moisturized black pepper were not affected by the fumigant treatment. The results of the postfumigation studies indicated that Salmonella Enteritidis was absent in the fumigated grains after drying and storage for 72 h, indicating a promising application for this technique. It was concluded that for Salmonella Enteritidis control, phosphine fumigation could be applied to black pepper grains before drying and the producers should rigidly follow good agricultural practices, mainly during the drying process, in order to avoid product recontamination. Additional work is needed to confirm the findings with more Salmonella serotypes and strains. [ABSTRACT FROM AUTHOR]

Abstract: A total of 47 stool samples were collected at the same stud farm from young foals with rotavirus diarrhoea and from their stud mares. Illness involved foals during three consecutive winter seasons. Infection in the farm appeared firstly in January–February 2008. After vanishing in the warm seasons, cases reappeared in March 2009 and 2010. Determination of the rotavirus G- and P-types was carried out using nested RT-PCR in samples collected in 2009 and 2010. A total of 19 of 47 samples resulted positive for rotavirus. The G type was determined in 19/47 samples, whereas the P genotype was determined in 17/47 samples. All equine strains presented a G14 VP7 in combination with a P[12] VP4, suggesting persistence of the same viral strain in the stud farm, during at least two consecutive winter periods. Sequence analysis of the genes encoding the outer capsid rotavirus proteins VP7 and VP4 revealed that the virus had a close relationship between strains recently isolated in the rest of Europe. [Copyright &y& Elsevier]

The interaction of reducing sugars, such as aldose, with proteins and the subsequent molecular rearrangements, produces irreversible advanced glycation end-products (AGEs), a heterogeneous class of non-enzymatic glycated proteins or lipids. AGEs form cross-links, trap macromolecules and release reactive oxygen intermediates. AGEs are linked to aging, and increase in several related diseases. The aim of this study was to assess, in a murine macrophage cell line, J774A.1, the effects of 48 h of exposure to glycated serum containing a known amount of pentosidine, a well-known AGE found in the plasma and tissues of diabetic and uremic subjects. Fetal bovine serum was incubated with ribose (50 mm) for 7 days at 37 °C to obtain about 10 nmol/ml of pentosidine. The cytotoxic parameters studied were cell morphology and viability by neutral red uptake, lactate dehydrogenase release and tetrazolium salt test. In the medium and in the intracellular compartment, bound and free pentosidine were evaluated by HPLC, as sensitive and specific glycative markers, and thiobarbituric acid reactive substances (TBARs), as index of the extent of lipid peroxidation. Our results confirm that macrophages are able to take up pentosidine. It is conceivable that bound pentosidine is degraded and free pentosidine is released inside the cell and then into the medium. The AGE increase in the medium was combined with an increase in TBARs, meaning that an oxidative stress occurred; marked cytotoxic effects were observed, and were followed by the release of free pentosidine and TBARs into the culture medium. [ABSTRACT FROM AUTHOR]

The concentration values of polychlorodibenzodioxins (PCDDs), polychlorodibenzofurans (PCDFs), and dioxin-like polychlorobiphenyls (DL-PCBs) in blood serum samples (pools) of metallurgical workers in the area of the city of Brescia (northern Italy) were statistically processed. As to workers' exposure characteristics, pools were divided into 34 professionally exposed (PE) and 11 non-professionally exposed (NPE). A further subdivision of PE pools was according to workplaces in which ferrous (N = 24) and non-ferrous (N = 10) materials were handled. To evaluate the aforesaid differences we applied the age-adjusted Generalized Linear Models. We identified significant (P ≤ 0.05) exposure models of the classification groups. The first subdivision was confirmed by the concentrations of 1,2,3,4,6,7,8-H 7 CDF, DL-PCB 105, and DL-PCB 189; the second was confirmed by the concentrations of PCDF TEQ 97 , PCDD + PCDF + DL-PCB (TEQ TOT ) TEQ 97 , 2,3,4,7,8-P 5 CDF, 1,2,3,6,7,8-H 6 CDD, 1,2,3,4,6,7,8-H 7 CDD, and PCB 189. Based on the literature, all mentioned congeners have been found in stack gas and fly ash samples of metallurgical plants: therefore, these indicators indicate the exposure to such work environments. Specifically, the concentrations measured in the workers’ blood serum appear to depend on the type of material processed during work. [ABSTRACT FROM AUTHOR]

The aims of this research were to evaluate mean echogenicity (ME) of the deep and superficial digital flexor tendons (DDFT and SDFT), the interosseous muscle (IM), and the accessory ligament of the deep digital flexor tendon (ALDDFT) of the metacarpal region in neonatal foals, and determine the effect of sex, side and body weight on this quantitative ultrasonographic evaluation. Thirteen orthopedically sound neonatal foals were examined. Four areas of study (1A, 1B, 2A, 2B) were identified. Transverse scans of the DDFT, SDFT, IM and ALDDFT were obtained, recorded, and analyzed. The most echogenic structures were the ALDDFT and DDFT, while the SDFT was significantly less echogenic than all other structures (P < 0.05). No influence of sex, forelimb, or body weight was observed. The echogenicity of the tenodesmic structures of foals partially overlapped that reported in the metacarpal region in adult horses, except for IM. [ABSTRACT FROM AUTHOR]

Abstract: The ability of a cellular construct to guide and promote tissue repair strongly relies on three components, namely, cell, scaffold and growth factors. We aimed to investigate the osteopromotive properties of cellular constructs composed of poly-ε-caprolactone (PCL) and rabbit bone marrow stromal cells (BMSCs), or BMSCs engineered to express bone morphogenetic protein 4 (BMP4). Highly porous biodegradable PCL scaffolds were obtained via phase inversion/salt leaching technique. BMSCs and transfected BMSCs were seeded within the scaffolds by using an alternate flow perfusion system and implanted into non-critical size defects in New Zealand rabbit femurs. In vivo biocompatibility, osteogenic and angiogenic effects induced by the presence of scaffolds were assessed by histology and histomorphometry of the femurs, retrieved 4 and 8 weeks after surgery. PCL without cells showed scarce bone formation at the scaffold–bone interface (29% bone/implant contact and 62% fibrous tissue/implant contact) and scarce PCL resorption (16%). Conversely, PCL seeded with autologous BMSCs stimulated new tissue formation into the macropores of the implant (20%) and neo-tissue vascularization. Finally, the BMP4-expressing BMSCs strongly favoured osteoinductivity of cellular constructs, as demonstrated by a more extensive bone/scaffold contact. [Copyright &y& Elsevier]

In September 2013 a waste-to-energy (WTE) incinerator located in the Turin area (Piedmont, Northern Italy) started to produce energy by the incineration of municipal solid wastes. The plant, one of the largest WTE incinerator in Europe, burns up to 490,000 tons of waste per year. A health surveillance program was implemented in order to evaluate the potential health effects on the population living near the plant. This program included a biomonitoring study aimed at assessing levels of several environmental contaminants including, among others, PCDDs, PCDFs, and PCBs. Before the WTE incinerator start-up (T 0), a group of 85 subjects (41 "exposed" and 44 "not exposed" subjects) was randomly selected for enrollment by the local health units among individuals aged 36–50 years who had been living in the same area for at least five years prior to the study. Subjects were balanced by exposure area, sex and five-year age classes. As from the study design, the same cohort was re-evaluated after three years of incinerator activity (T 2). A parallel study was conducted on a group of 12 farmers living and/or working in farms located in an area in the range of 5 km around the incinerator. Results of this study did not evidence any impact of the WTE plant on human exposure to PCDDs, PCDFs, and PCBs. In fact, no significant differences were found in the concentrations of PCDDs + PCDFs, DL-PCBs, and NDL-PCBs measured in the population group residing near the plant after three years of activity (T 2) with respect to the control group. A significant decrease of serum concentrations of all the analytes was observed at T 2 in both groups compared to T 0. Serum concentrations of PCDDs, PCDFs, and PCBs in the group of farmers were higher than those observed in the adult population under study. [Display omitted] • Human exposure to waste incinerator emissions is of great concern. • No impact of the WTE plant was observed on human exposure to PCDDs, PCDFs, and PCBs. • PCDD, PCDF and PCB decrease was observed at T 2 in exposed and not exposed groups. • Observed concentrations of PCDDs, PCDFs, and PCBs were higher in females. [ABSTRACT FROM AUTHOR]

Abstract: Lung transplantation (LT) is the only effective form of therapy for cystic fibrosis (CF) associated with end-stage pulmonary failure. In Italy, the management of CF is regulated by national law, which has instituted regional centers for care and follow-up of all CF patients. LT has been performed since 1992 in only nine LT certified centers. The structured national organization has led to a unified database for LT for CF. As of December 2006, 197 bilateral LT (96 male and 94 female patients; 7 retransplants) have been performed. Of these, four had also liver or heart and liver transplantation, and three are long-term survivors. Overall median survival is 7 years. Mean age at transplantation is 26.5 years, and the mortality on the waiting list is 33.6%. Patients listed for transplant either received a suitable donor within a mean of 10 months or died within a mean of 5.5 months. The most frequent cause of death is bronchiolitis obliterans syndrome (BOS). Our nationwide database indicates the excellent results obtained by LT in FC. Still, mortality on the waiting list remains a challenge and long-term outcome is limited by BOS. [Copyright &y& Elsevier]

In this source apportionment study, an original approach based on receptor modelling was tested to relate primary and secondary organic aerosol (OA) contributions - estimated from ACSM (Aerosol Chemical Speciation Monitor) measurements - to their emission sources. Moreover, thanks to the coupling of optical and chemical variables as input to the receptor model, information such as the impact of mineral dust to the aerosol absorption in the atmosphere and estimates for the absorption Ångström exponent (α) of the sources were retrieved. An advanced source apportionment study using the Multilinear Engine (ME-2) was performed on data collected during February 2017 in Rome (Italy), in the frame of the CARE (Carbonaceous Aerosol in Rome and Environs) experiment. A complete chemical characterisation (elements, non-refractory components, and carbonaceous components) was carried out, and the aerosol absorption coefficients b ap (λ) at 7 wavelengths (370, 470, 520, 590, 660, 880, and 950 nm) were retrieved by an Aethalometer AE33; all these variables (chemical + optical) were used as input to the receptor model. The final constrained solution consisted of nine factors which were assigned to major sources impacting on the investigated site (hereafter sources are referred to as: biomass burning, nitrate and aged aerosol, traffic exhaust, sulphate, mineral dust, marine aerosol, traffic non-exhaust, local source, and polluted marine aerosol), comprising both local urban sources and contributions from long-range transport. The bootstrap analysis supported the goodness of the solution. Total OA concentration from ACSM was apportioned by our receptor model and afterwards compared with HOA (hydrocarbon-like organic aerosol), BBOA (biomass burning-like organic aerosol), and OOA (oxygenated organic aerosol) concentrations obtained as results from an independent source apportionment study previously performed. As an original result of this work, insights on OA contributions were thus retrieved: (1) the contribution of organic aerosol assigned by ME-2 to the traffic exhaust source was fully comparable to HOA assessed by ACSM data analysis; (2) our source apportionment results gave the relevant indication that the OOA apportionment made on ACSM data likely includes a secondary OA contribution due to biomass burning. Other relevant results came from b ap apportionment obtained by our multi-variable source apportionment approach: traffic exhaust was the main contributor to aerosol absorption in the atmosphere, but mineral dust contribution was also notable when a not negligible mineral dust transport episode was registered at the measurement site. In addition, source dependent optical absorption parameters (i.e. the absorption Ångström exponent - α - and the mass absorption cross section at different wavelengths) were retrieved without any a-priori assumption. In perspective, our modelling approach paves the way to more powerful source apportionment approaches which have the potential of providing much more insights on aerosol properties and sources. Image 1 [ABSTRACT FROM AUTHOR]