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Accurate calculations of the potential energy surface of the N+O2 reaction have been performed at complete active space self-consistent field (CASSCF) and multireference single–double configuration interaction (MR-SDCI) levels. Features of the calculated potential energy values are analyzed and compared with those of previous ab initio calculations and experimental data. The comparison has been extended to kinetic properties of the reaction. © 1995 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Abstract: The relationship between work rate (WR) and its tolerable duration (t LIM) has not been investigated at high altitude (HA). At HA (5050m) and at sea level (SL), six subjects therefore performed symptom-limited cycle-ergometry: an incremental test (IET) and three constant-WR tests (% of IET WRmax, HA and SL respectively: WR1 70±8%, 74±7%; WR2 86±14%, 88±10%; WR3 105±13%, 104±9%). The power asymptote (CP) and curvature constant (W′) of the hyperbolic WR–t LIM relationship were reduced at HA compared to SL (CP: 81±21 vs. 123±38W; W′: 7.2±2.9 vs. 13.1±4.3kJ). HA breathing reserve (estimated maximum voluntary ventilation minus end-exercise ventilation) was also compromised (WR1: 25±25 vs. 50±18lmin−1; WR2: 4±23 vs. 38±23lmin−1; WR3: −3±18 vs. 32±24lmin−1) with near-maximal dyspnea levels (Borg) (WR1: 7.2±1.2 vs. 4.8±1.3; WR2: 8.8±0.8 vs. 5.3±1.2; WR3: 9.3±1.0 vs. 5.3±1.5). The CP reduction is consistent with a reduced O2 availability; that of W′ with reduced muscle–venous O2 storage, exacerbated by ventilatory limitation and dyspnea. [Copyright &y& Elsevier]

During collection on filter-based aerosol samplers, organic and inorganic aerosol compounds both contribute to positive and negative artefacts, significantly affecting chemical analyses results for single species and PM mass concentrations. Up to now, studies on organic or inorganic artefacts have been conducted in Europe but very scarce data are available for both in a single study. The field study was carried out in Milan, which is located in the Po valley (Northern Italy) one of the major pollution hot spots in Europe. As sampling artefacts depend on many factors, such as filter type, face velocity, sampling duration, and ambient conditions, in this field study two different filter types have been considered (i.e. quartz fibre filters and Teflon filters) for the assessment of both inorganic and organic artefacts during two different seasons (performing also some samplings at different flow-rates). Results showed that positive artefacts due to OC adsorption on quartz filters accounted for 39% of the OC measured concentration in summer, and 23% in winter. Negative artefact due to nitrate volatilisation by the filters was 51% on Teflon and 22% on the quartz filters in summer, and no or negligible losses were observed in winter. A significant improvement in the PM mass comparability obtained in parallel samplings on different filters was obtained taking into account the artefact estimates performed in this study. [Copyright &y& Elsevier]

Exercise tolerance inversely correlates with the severity of the disease in patients with idiopathic pulmonary arterial hypertension (IPAH). Cycling and walking protocols are commonly utilized in the evaluation of exercise intolerance in IPAH, but little information exists on possible differences in ventilatory and gas exchange adaptations to these exercise modalities. In a group of patients with moderate to severe IPAH (n = 13), we studied the ventilatory, cardiovascular and gas exchange adaptations to maximal incremental walking (W) and maximal incremental cycling (C). During W, compared to C, the ventilatory equivalents for CO(2) output (V'(E)/V'CO(2)) were significantly higher either expressed as the rate of increment (56 +/- 5 vs. 45 +/- 3; P < 0.0001) or as the absolute values at anaerobic threshold (AT) and at peak exercise. At AT, the increase in V'(E)/V'CO(2) during W was associated with a significant lower value of end-tidal carbon dioxide. At peak W, compared to peak C, dyspnea sensation was higher and arterial oxygen saturation (SpO(2)) was lower (87 +/- 2 vs. 91 +/- 2, P < 0.001). In patients with IPAH the physiologic information obtained with W are different from those obtained with C. Tolerance to W exercise is limited by high ventilatory response and dyspnea sensation. W should be used to assess the degree of lung gas exchange inefficiency and arterial O(2) desaturation during exercise. [ABSTRACT FROM AUTHOR]

Results obtained during a winter field campaign for the fine fractions of particulate matter are presented. A high pollution episode together with an analysis of the main factors, which influence accumulation of pollutants is described. The measurement campaigns were carried out simultaneously at two sites in Northern Italy, Milan and Erba, during the winter of 2000. The daily variability in the mass concentration values and PM2.5/PM10 ratios appeared to be strongly dependent upon meteorological and atmospheric stability conditions and, in particular, wind regimes. During the intensive field campaign a high-pollution episode occurred that led to TSP and fine fraction concentrations well above the attention and alarm thresholds, reaching values of up to 200–250 μg m−3. The elemental concentrations were determined by ED-XRF analysis. The elemental composition of the particulate matter indicated that crustal matter oxides (soil dust) were the main component in particles with aerodynamic diameter dae>10 μm. They were an important part also in particles with 2.5

Because the use of herbal therapies in the U.S. is escalating, it is essential to be aware of clinical and adverse effects, doses and potential drug-herb interactions. A consumer poll in 1998 indicated that one-third of respondents use botanical remedies, and nearly one in five taking prescription medications also used herbs, high-dose dietary supplements or both. An estimated 15 million adults are at risk for potential adverse interactions involving prescription medications and herbs or vitamin supplements, yet most practicing physicians have little knowledge of herbal remedies or their effects. Herbal products are marketed without the proof of efficacy and safety that the Food and Drug Administration (FDA) requires of drugs. The Dietary Supplement and Health Education Act of 1994 allocates responsibility to manufacturers for ensuring safety and efficacy with no specific requirements to submit documentation. Manufacturers may state a product's physiologic effects but may not make claims for the treatment or cure of specific diseases. Consumers and practitioners have little information about product safety, contraindications, interactions or effectiveness and are reliant on manufacturers to provide accurate labeling. Recently, the growing number of foods with herbs has raised concerns at the FDA, which requires evidence that food additives are safe. Considering that the growing appeal of herbal remedies is likely to continue, physicians, particularly cardiologists, must become familiar with the available cardiovascular information on herbs. This review highlights the existing data on the efficacy, adverse effects and interactions for herbal therapies that impact on the cardiovascular system. [ABSTRACT FROM AUTHOR]

In this paper, measurements of short- and long-lived Radon progeny attached to atmospheric fine aerosols are reported. Hourly measurements of 222Rn short-lived decay products (i.e. 214Bi via on-line alpha spectrometry on 214Po) in the atmosphere were carried out in Milan (Italy) from 1999 to 2016; 214Bi mean concentrations ranged from 0.2 to 38.1 Bq m−3. It is noteworthy that minima occurred in springtime although the strongest convective turbulence can be expected in summer, when the highest solar radiation is available; one order of magnitude higher values were observed in winter when the Po valley experienced poor atmospheric dilution. The Theil-Sen method was applied to investigate the long-time trend in de-seasonalised data series. Results showed that - although inter/intra-annual variations in 214Bi concentrations were observed in connection with differences in atmospheric dispersion conditions – no statistically significant trend over the investigated period was detected. On a sub-set of these samples, also weekly 210Pb concentrations were determined via off-line alpha spectrometry on 210Po; atmospheric activity concentration values ranged between 0.13 and 3.05 mBq m−3. The seasonal behaviour of 210Pb concentrations followed fairly well the 214Bi temporal pattern, showing that mixing layer dynamics is paramount in determining short- and long-lived Radon progeny levels in the atmosphere. From 210Pb/214Bi activity ratio, the residence time τ res of fine aerosols in the atmosphere was estimated to be on average 1 day, ranging from 11.0 to 55.3 h without any evident temporal trend. By exploiting the availability of mixing layer height data at our site, an alternative approach to estimate aerosol residence time was tested; this was based on a simple relationship relying on deposition velocity (from literature data) and mixing layer height (available at our monitoring station). Mean experimental τ res resulted in 1.2 days which was comprised in the 0.6–2.0 days range estimated by the alternative method. This result brings a noteworthy contribution to the scientific debate about differences among aerosol residence time estimates obtained by different radioactive parent-daughter couple; our results show that the 210Pb/214Bi (or equivalently 210Pb/222Rn) couple provides reliable estimates. Unlabelled Image • Natural radioactive isotopes are effective tracers to study atmospheric processes. • Fine aerosol residence times retrieved through long- and short-lived Radon progeny. • Fine aerosol residence times in Milan ranged between 11 and 55 h. • Residence time reliability assessed by deposition velocity and mixing layer height. [ABSTRACT FROM AUTHOR]

Abstract Air pollution events at urban locations are driven by both emissions and atmospheric dispersion conditions. Atmospheric dispersion is not routinely assessed at monitoring networks thus preventing the possibility of understanding if high pollution events are due to increasing emissions or to the occurrence of atmospheric stability conditions. In principle, this piece of information would be very useful to implement effective strategies for pollution abatement. In this work, an 18-year long dataset of radon (222Rn) progeny measurements was used to estimate equivalent mixing layer heights (hereafter referred to as MH) with hourly resolution by means of a box model. Mean MH obtained by more conventional modelling approaches based on turbulence variables on a 5-year long dataset agreed very well with results obtained by the box model. It is noteworthy that in the literature there are scarce MH data for such long periods and comparisons between estimates by radioactive tracers and other approaches are often limited to a few days/weeks. Results suggested that relatively simple methods like the one here proposed could be implemented at pollution monitoring stations in order to improve available information and better understand the evolution of pollution events on 1-h timescale. In addition, the long-term assessment here presented provides useful data to pursue MH climatological studies. Graphical abstract Image 1 Highlights • Radon and its progeny are good markers for atmospheric dispersion conditions. • Short-lived radon decay products measured for 18 years with 30 min resolution. • A box model based on radon concentrations estimated equivalent mixing layer heights. • Radon-based and turbulence-based estimates for MH resulted comparable. • Radon measurements at monitoring stations could be effectively implemented. [ABSTRACT FROM AUTHOR]

Exercise testing is increasingly utilized to evaluate the level of exercise intolerance in patients with lung and heart diseases. Cardiopulmonary exercise testing (CPET) is considered the gold standard to study a patient’s level of exercise limitation and its causes. The 2 CPET protocols most frequently used in the clinical setting are the maximal incremental and the constant work rate tests. The aim of this review is to focus on the main respiratory diseases for which exercise tolerance is indicated; for example, chronic obstructive pulmonary disease, interstitial lung disease, primary pulmonary hypertension and cystic fibrosis. This review also focuses on the variables/indices that are utilized in the functional and prognostic evaluation. The recognition of abnormal response patterns of ventilatory, cardiac and metabolic limitation to exercise may help in the diagnostic evaluation. In addition, CPET indexes can provide important functional and prognostic information regarding patients with pulmonary disease. Exercise indices, such as peak oxygen uptake (V’O2 peak), ventilatory equivalents for carbon dioxide production (V’E-/V’CO2) and arterial oxygen saturation (SpO2), have in fact proven to be better predictors of prognosis than lung function measurements obtained at rest. Moreover, useful information on the effects of therapeutic interventions may be obtained by CPET by studying the changes in endurance capacity during high-intensity constant work rate protocols. Copyright © 2009 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

To clarify the spawning seasonal dynamics of common carp (cyprinus carpio) in northeast Italy, female fish were collected monthly from July 2002 to June 2003. The gonadosomatic index (GSI), histomorphology, 17β-estradiol serum concentration, and relative fecundity were compared. Between March-April and May-June, statistically significant differences were found in GSI, 17β-estradiol, and relative fecundity. Intermediate multispawner stages were found by histological analysis of specimens caught in July-August 2002 and May-June 2003. Final maturation stage was found mostly in March-April. Development trends were well correlated with water temperature. Histomorphological analysis revealed that oocytes at the exogenous vitellogenesis stage were retained throughout the winter and final maturation was reached during a short period (March-April). The beginning of the spawning season was fixed between April and May, and the end of spawning occurred during July and August. [ABSTRACT FROM AUTHOR]

In this paper, results on a PM10 daytime–nighttime measurement campaign carried out in Milan to study the evolution of PM10 concentration and composition in relation to atmospheric dispersion conditions are shown. To account for the evolution of atmospheric dispersion conditions, Radon hourly concentration measurements were performed. The significant correlation between PM10 and 222Rn daytime concentrations evidences the dominant role of atmospheric dispersion in determining the temporal variation of PM10 levels. Whenever 222Rn concentrations accumulate during the night (indicating the formation of nocturnal atmospheric stability conditions), PM10 concentrations are higher than those registered during the daytime before, despite a decrease in emissions from active sources. On the contrary, when 222Rn concentrations do not accumulate during night hours, PM10 levels are lower than those measured during the daytime before. As concerns the average elemental concentrations (in ngm−3), the nighttime–daytime variations are in the range −17% to +37%; during the night, soil-related elements (Al, Si, Ca, Ti) decrease while anthropogenic elements (Zn, Cu, Fe, Pb) increase. A case study concerning a ‘green’ Sunday (when traffic was forbidden from 8a. M. To 8p. M. ) is also discussed. The difference of PM10 concentration and elemental composition registered during the ‘green’ Sunday daytime and the following nighttime, together with the information on atmospheric dilution power obtained by Radon measurements, allowed the characterisation of the traffic source elemental profile and increased the comprehension of the low effectiveness of some PM10 reduction strategies. [Copyright &y& Elsevier]

Abstract: Weekly measurements of 210Pb activity concentration on aerosol particles were performed at ground level in outdoor air in Milan (Italy) during the years 2000–2001. The experimental method was based on the delayed alpha spectrometry of in-grown 210Po activity detected on airborne particles collected on a filter support. On the same filter the 214Pb activity concentration was also measured during the sampling. 210Pb weekly concentration values showed a great variability and the average monthly values exhibited a seasonal pattern characterised by maxima in winter and minima in spring–summer. The same seasonal trend was also observed in 214Pb concentration values. 210Pb average yearly values were 0.70 and 0.82mBq/m3 in 2000 and 2001, respectively, in good agreement with literature data registered at continental sites of similar latitude and longitude. The activity ratio 210Pb/214Pb was used to evaluate the residence time of fine aerosols in the urban air of Milan, which was 1–2 days. [Copyright &y& Elsevier]

The seasonal variation of PM1 and PM2.5 mass concentration and composition has been investigated in the great urban area of Milan. PM samplings were carried out 3 times a week during the year 2002. Mass and elemental concentrations were measured in all samples and in a limited number of filters also the elemental and organic carbon contribution (EC and OC) was determined.In the urban area of Milan, PM2.5 comprises about 60% and 70% of the PM1 mass in summer and in winter, respectively. Among the measured PM components carbon compounds and sulphates are by far the major contributors and a significant contribution likely due to nitrates (not measured) should also be considered. PM1 and PM2.5 concentration and composition show a strong seasonal behaviour, which was studied in relation to atmospheric dispersion conditions.Our approach is based on the use of Radon concentration as a natural tracer of differences in the average mixing layer height during the year. The application of a suitable “Radon index” allows the normalisation of PM mass and elemental data to account for the seasonal effect due to differences in atmospheric dispersion conditions. [Copyright &y& Elsevier]

In this paper a source apportionment of particulate matter pollution in the urban area of Milan (Italy) is given. Results of PM10 and PM2.5 mass and elemental concentrations from a 1-year monitoring campaign are presented. Mean annual and daily PM10 levels are compared with the limits of the EU Air Quality Directive EC/30/1999 and the results show that the limit values established would not be met in the urban area of Milan or the large surrounding area. Moreover, high levels of PM2.5 are registered and this fraction constitutes a high portion of the PM10 mass. In Milan the winter period is characterised by a high degree of air pollution due to a greater contribution of emissions and to adverse meteorological and thermodynamic conditions of the atmosphere. The application of multivariate techniques and receptor modelling (PCFA, APCFA) to the whole data-set led to the identification of the main emitting sources and to the source apportionment of PM10 and PM2.5 in Milan. The most important sources were identified as ‘soil dust’, ‘traffic’, ‘industry’ and ‘secondary compounds’ for PM10 and as ‘soil dust’, ‘anthropogenic’ and ‘secondary compounds’ for PM2.5, explaining the greatest part of the total variance (91% and 75%, respectively). [Copyright &y& Elsevier]

Continuous measurement of hourly concentrations of 212Pb attached to aerosol particles was carried out during the whole year 2000 in the outdoor air of Milan (Italy).An improved experimental method based on on-line alpha spectroscopy during atmospheric particulate matter sampling allowed the contemporary determination of 212Pb and 214Bi through the deconvolution of the alpha energy spectral distribution analysis.The 212Pb hourly concentrations were about 100 times lower than 214Bi but showed a similar characteristic diurnal time trend. However, the influence of meteorological parameters such as rain and wind was more evident in 212Pb than in 214Bi concentrations.The 212Pb average annual concentration was 0.090±0.060 Bq/m3 with daily mean concentration varying from 0.013 to 0.333 Bq/m3. [Copyright &y& Elsevier]

Aim: The study was aimed at assessing the effect of β-sitosterol on carbohydrate metabolic enzymes in high-fat diet and sucrose-induced type-2 diabetic rats. Experimental design: Adult male Wistar rats were used and divided into four groups: Group I: Control; Group II: Type-2 diabetic rats; Group III: Type-2 diabetic rats treated with β-sitosterol (20 mg/kg b.wt/day, orally for 30 days); and Group IV: Type-2 diabetic rats treated with metformin (50 mg/kg b.wt/day, orally for 30 days). After 30 days of treatment, animals were anesthetized; liver tissues were dissected out and used for the assessment of glucokinase, glucose-6-phosphatase, glycogen synthase, glycogen phosphorylase, and phosphoenolpyruvate carboxykinase (PEPCK) enzyme activities which were studied by spectrophotometric analysis. Results: The activity of glucose-6-phosphatase, glycogen phosphorylase, and PEPCK was significantly raised (P < 0.05) in type-2 diabetic rats. Conversely, glucokinase and glycogen synthase activities were significantly reduced (P < 0.05) in type-2 diabetic rats. Oral administration of the plant sterol (β-sitosterol) could effectively normalize the detrimental changes caused by high diet induction to that of the control and standard drug metformin. Conclusion: The present study shows that β-sitosterol regulates carbohydrate metabolic enzymes in the liver, thereby β-sitosterol may have therapeutic potential candidate for the management of type-2 diabetes. [ABSTRACT FROM AUTHOR]

Background: Prostate cancer (PCa) is the second most typical cancer and also the sixth leading reason behind cancer death among men worldwide with associate degree calculable recorded amount of 1.1 million cases and 307,000 deaths in 2012. Chebulagic acid (CA), a benzopyran tannin, is one of the major bioactive compounds present in the fruits of Terminalia chebula. Aim: The present study was aimed at assessing the effects of CA on proapoptotic (Bax) and antiapoptotic protein molecules such as B-cell lymphoma-2 (Bcl-2) and Bcl-extra large (Bcl-xl) in PC-3 cell line. Materials and Methods: Antiproliferative potential of CA was determined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. PC-3 cells were treated with different concentration of CA (1, 5, 10, 25, 50, and 100 μM). Pro- and anti-apoptotic proteins were done by western blotting methods. PC-3 cells were treated with the treatment of CA resulted in a dose-dependent inhibition of the growth of PC-3 cells. This was associated with increased levels of proapoptotic protein (Bax) and the reduced levels of the antiapoptotic proteins Bcl-2 and Bcl-xL. Conclusion: The present findings clearly suggest that CA induces apoptosis by the regulating intrinsic pathways which could be very useful for the treatment of PCa. [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]

A comprehensive range of gas and particle phase pollutants were sampled at 1-hour time resolution in urban background Milan during summer 2012. Measurements include several soluble inorganic aerosols ( Cl − , NO 2 − , NO 3 − , SO 4 2 − , Ca 2 + , K + , Mg 2 + , Na + , NH 4 + ) and gases (HCl, HNO 2 ,HNO 3 , NH 3 , NO, NO 2 ,O 3 , SO 2 ), organic, elemental and black carbon and meteorological parameters. Analysis methods used include mean diurnal pattern on weekdays and Sundays, pollution roses, bivariate polar plots and statistical models using backtrajectories. Results show how nitrous acid (HONO) was mainly formed heterogeneously at nighttime, with a dependence of its formation rate on NO 2 consistent with observations during the last HONO campaign in Milan in summer 1998, although since 1998 a drop in HONO levels occurred following to the decrease of its precursors. Nitrate showed two main formation mechanisms: one occurring through N 2 O 5 at nighttime and leading to nitrate formation onto existing particles; another occurring both daytime and nighttime following the homogeneous reaction of ammonia gas with nitric acid gas. Air masses reaching Milan influenced nitrate formation depending on their content in ammonia and the timing of arrival. Notwithstanding the low level of SO 2 in Milan, its peaks were associated to point source emissions in the Po valley or shipping and power plant emissions SW of Milan, beyond the Apennines. A distinctive pattern for HCl was observed, featured by an afternoon peak and a morning minimum, and best correlated to atmospheric temperature, although it was not possible to identify any specific source. The ratio of primary-dominated organic carbon and elemental carbon on hourly PM 2.5 resulted 1.7. Black carbon was highly correlated to elemental carbon and the average mass absorption coefficient resulted MAC = 13.8 ± 0.2 m 2 g −1 . It is noteworthy how air quality for a large metropolitan area, in a confined valley and under enduring atmospheric stability, is nonetheless influenced by sources within and outside the valley. [ABSTRACT FROM AUTHOR]

In Po valley (Northern Italy) concentrations of particulate matter (PM) often exceed air quality standards, and road traffic is reported as one of the main sources of pollution. This study investigates the size resolved particle number concentration and size distribution at one rural station, one urban station and one traffic station. The measured size-resolved particle number concentration has been reduced by means of cluster analysis to four particle size fractions (cluster 1: 7–29 nm, cluster 2: 29–95 nm, cluster 3: 95–264 nm, and cluster 4: 264–10,000 nm) based on their behavior in atmosphere according to common time patterns. The primary emissions from traffic are evaluated based on black carbon (BC) and size-resolved particle number concentration data, considering separately single size intervals and providing cluster-resolved information on primary and newly formed particle concentration. Particles directly emitted by vehicle exhaust exhibit similar numbers for the clusters 1 to 3 while newly formed particles mainly occurs in cluster 1. Furthermore, diurnal variation of directly emitted particles is found to closely follow the BC levels, while the trend of newly formed particles varies according to air temperature, solar radiation and particle pollution levels. The results release that in Po valley the variations of particle number levels do not always reflect the variation of road traffic emissions in urban areas as the large availability of anthropogenic precursors can favor summertime nucleation events with region-wide extension. [ABSTRACT FROM AUTHOR]

Advanced receptor models have been recently developed and tested in order to improve the resolution of apportionment problems reducing rotational ambiguity of results and aiming at identifying a larger number of sources. In particular, multi-time model is a factor analysis method able to compute source profiles and contributions using aerosol compositional data with different time resolutions. Unlike traditional factor analysis, each measured value can be inserted into multi-time model with its original time schedule, thus all temporal information can be effectively used in the modelling process. In this work, multi-time model was expanded in order to impose constraints on modelled factors aiming at improving the source identification. Moreover, as far as we know for the first time, a suitable bootstrap technique was implemented in the multi-time scheme to estimate the uncertainty of the final constrained solutions. These implemented approaches were tested on a PM2.5 (particulate matter with aerodynamic diameter < 2.5 μm) dataset composed of 24-h samples collected during one year and hourly data sampled in parallel for two shorter periods in Florence (Italy). The daily samples were chemically characterised for elements, ions and carbonaceous components while elemental concentrations only were available for high-time resolved samples. The application of the advanced model revealed the major contribution from traffic (accounting for 37% of PM2.5 as annual average) and allowed an accurate characterisation of involved emission processes. In particular, exhaust and non-exhaust emissions were identified. The constraints imposed in the continuation run led to a better description of the factor associated to nitrates and also of biomass burning profile and the bootstrap results gave useful information to assess the reliability of source apportionment solutions. Finally, the comparison with the results computed by ME-2 base model applied to daily and hourly compositional data separately demonstrated the advantages provided by the multi-time approach. [ABSTRACT FROM AUTHOR]

In this paper, a new way to apportion the absorption coefficient (b abs ) of carbonaceous atmospheric aerosols starting from a multi-wavelength optical analysis is shown. This methodology can disentangle and quantify the contribution to total absorption of equivalent black carbon (EBC) emitted by wood burning (EBC WB ) and fossil fuel (EBC FF ) as well as brown carbon (BrC) due to incomplete combustion. The method uses the information gathered at five different wavelengths in a renewed and upgraded version of the approach usually referred to as Aethalometer model. Moreover, we present the results of an apportionment study of carbonaceous aerosol sources performed in a rural area and in a coastal city, both located in the North-West of Italy. Results obtained by the proposed approach are validated against independent measurements of levoglucosan and radiocarbon. At the rural site the EBC WB and EBC FF relative contributions are about 40% and 60% in winter and 15% and 85% in summer, respectively. At the coastal urban site, EBC WB and EBC FF are about 15% and 85% during fall. The OC contribution to the wood burning source at the rural site results approximately 50% in winter and 10% in summer and about 15% at the coastal urban site in fall. The new methodology also provides a direct measurement of the absorption Ångström exponent of BrC (α BrC ) which resulted α BrC = 3.95 ± 0.20. [ABSTRACT FROM AUTHOR]

In this study, the Multilinear Engine (ME-2) receptor model was applied to speciated particulate matter concentration data collected with two different measuring instruments upwind and downwind of a steelworks complex in Port Talbot, South Wales, United Kingdom. Hourly and daily PM samples were collected with Streaker and Partisol samplers, respectively, during a one month sampling campaign between April 18 and May 16, 2012. Daily samples (PM 10 , PM 2.5 , PM 2.5–10 ) were analysed for trace metals and water-soluble ions using standard procedures. Hourly samples (PM 2.5 and PM 2.5–10 ) were assayed for 22 elements by Particle Induced X-ray Emission (PIXE). PM 10 data analysis using ME-2 resolved 6 factors from both datasets identifying different steel processing units including emissions from the blast furnaces (BF), the basic oxygen furnace steelmaking plant (BOS), the coke-making plant, and the sinter plant. Steelworks emissions were the main contributors to PM 10 accounting for 45% of the mass when including also secondary aerosol. The blast furnaces were the largest emitter of primary PM 10 in the study area, explaining about one-fifth of the mass. Other source contributions to PM 10 were from marine aerosol (28%), traffic (16%), and background aerosol (11%). ME-2 analysis was also performed on daily PM 2.5 and PM 2.5–10 data resolving 7 and 6 factors, respectively. The largest contributions to PM 2.5–10 were from marine aerosol (30%) and blast furnace emissions (28%). Secondary components explained one-half of PM 2.5 mass. The influence of steelworks sources on ambient particulate matter at Port Talbot was distinguishable for several separate processing sections within the steelworks in all PM fractions. [ABSTRACT FROM AUTHOR]

Abstract: In this work, light-absorption measurements were carried out on quartz-fibre and PTFE (i.e. Teflon®) filters using a home-made polar photometer in order to assess the role of organic sampling artefacts on optical measurements. Filter-based light-absorption instruments are generally operated with quartz/glass-fibre filter tapes and – as far as we know – currently there are no systematic studies on the sampling artefacts affecting the light absorption coefficient measurements. In this work, particulate matter (PM) samples were collected in Milan (Italy) during different sampling campaigns with the aim of (1) validating the polar photometer; (2) comparing the absorption properties measured on PM collected on different filter media; (3) investigating the causes of the observed differences. The polar photometer was demonstrated to give aerosol light absorption coefficients (σ ap in Mm−1) fully comparable to those obtained by a Multi-Angle Absorption Photometer (MAAP) when using quartz-fibre filters to collect atmospheric particles. The aerosol light absorption coefficients determined on samples collected in parallel on quartz-fibre and PTFE filters showed significant differences (about 40%). These differences were much lower (i.e. 8%) when the quartz-fibre filter sampling line was equipped with a denuder to remove organic gases from the incoming air stream evidencing a relevant role of organic sampling artefacts in light absorption measurements by filter-based systems. [Copyright &y& Elsevier]

Context: High altitude (HA) is a model of severe hypoxia exposure in humans. We hypothesized that nocturnal hypoxemia or acute maximal exercise at HA might affect plasma leptin and VEGF levels. Objectives: Plasma leptin, VEGF and other metabolic variables were studied after nocturnal pulse oximetry and after maximal exercise in healthy lowlanders on the 3rd-4th day of stay in Lobuche (5050 m, HA) and after return to sea level (SL). Results: Leptin was similar at SL or HA in both pre- and post-exercise conditions. Pre-exercise VEGF at HA was lower, and cortisol was higher, than at SL, suggesting that nocturnal intermittent hypoxia associated with periodic breathing at HA might affect these variables. Conclusions: Leptin levels appear unaffected at HA, whereas nocturnal hypoxic stress may affect plasma VEGF. Future HA studies should investigate the possible role of nocturnal intermittent hypoxemia on metabolism. [ABSTRACT FROM AUTHOR]

Abstract: We introduce a simple, fully automatic, multi-wavelength and non-destructive optical system, namely a Multi-Wavelength Absorbance Analyzer (MWAA), to measure off-line the light absorption in Particulate Matter (PM) collected on filters and hence to derive the black and brown carbon content in the PM. This gives the opportunity to measure in the same sample the concentration of PM mass by gravimetric analysis, black and brown carbon, elements by, for instance, X Ray Fluorescence, and finally ions by Ion Chromatography. Furthermore, the multi-wavelength analysis gives the possibility to apportion black and brown/organic carbon sources through the direct determination of the Angstrom exponent and a revised version of the so-called “the aethalometer method”. Up to 16 samples can be analyzed in sequence and in an automatic and controlled way within a few hours. The filter absorbance measured by MWAA was successfully validated both against a MAAP and a polar photometer. Our MWAA was used in several field campaigns with PM2.5 (PM with aerodynamic diameter less than 2.5μm) samples collected on quartz fiber filters, and the mass absorption cross section at λ=405, 635 and 850nm was obtained measuring at the same time the EC in particulate matter samples by thermal-optical analysis using the EUSAAR_2 protocol. First results on the MWAA application to the analysis of size-segregated samples collected by multi-stage impactor are also shown. [Copyright &y& Elsevier]

Abstract: This work aims at gaining information on the effects of different thermal treatments on radiocarbon measurements of organic (OC) and elemental (EC) carbon fractions in the atmospheric aerosol. Improvements to the traditional approaches for the determination of the fraction of modern carbon of OC and EC−f m(OC) and f m(EC)- are proposed. As for f m(EC) determination, we propose to add a He step at high temperature to the standard oxygen treatment. Our tests demonstrate that the addition of a high temperature He step (final choice: 750°C) to the oxygen treatment is effective in removing the refractory OC. As for f m(OC) determination, we propose to quantify it by measuring either the fraction of modern carbon of TC and EC or the fraction of modern carbon of water soluble (f m(WSOC)) and water insoluble (f m(WINSOC)) organic carbon to limit the influence of possible pyrolysis on the direct determination of f m(OC). Tests on the equivalence of the approaches have shown good agreement between them. Our tests were carried out on samples collected in a heavily polluted area (Milan, Italy) during wintertime. f m(OC), f m(EC), and f m(TC) values obtained in our tests were also used to attempt a preliminary source apportionment in the area using 14C measurements. Wintertime EC resulted to be mainly fossil (84%), whereas OC was dominated by modern contribution (63%). Two approaches were tested for the evaluation of the wood burning contribution to OC and a good agreement was found. Wood burning primary contribution accounted for about 18% of OC in Milan during wintertime. Secondary OC from biomass burning and the contribution from other urban sources were tentatively identified following literature approaches, with the aim of evaluating the biogenic contribution to OC in the area, which was estimated to be about 18%. [Copyright &y& Elsevier]

Abstract: In southern European countries, Saharan dust may episodically produce significant increases of PM10, which may also cause the exceedance of the PM10 daily limit value established by the European Directive (2008/50/EC). The detection with very high sensitivity of all the elements that constitute mineral dust makes PIXE technique a very effective tool to assess the actual impact of these episodes. In this work, a review of long-term series of elemental concentrations obtained by PIXE has been accomplished with the aim of identifying the occurrence of Saharan dust transport episodes over long periods in Tuscany and characterising them in terms of composition and impact on PM concentration, tracing back their contribution to the exceedances of the PM10 limit value. The impact of the different Saharan intrusions on PM10 showed a very high variability. During the most intense episodes (which occurred with a frequency of few times per year) the calculated soil dust concentration reached values as high as 25–30 μg m−3, to be compared with background values of the order of 5 μg m−3. The Saharan dust contribution was decisive to cause the exceedance of the PM10 daily limit value in the 1–2% of the days considered in the present work. [Copyright &y& Elsevier]

Abstract: In this work, a methodology based on the macro-tracer approach was improved to obtain a more reliable estimate of the wood burning impact on PM10 and OC concentrations. Indeed, literature emission factors were weighed by the wood consumption data available for the investigated region and these tailored factors were used in the calculation. Moreover, an alternative approach using the chemical profile of the wood burning source obtained by the Positive Matrix Factorization was introduced. As far as we know, this is the first time that PMF-derived emission ratios instead of source emission factors are used in the macro-tracer method. A critical comparison of the results obtained by the two approaches was carried out. The results suggest that PMF-derived emission ratios can be a feasible alternative to the widely used wood smoke emission factors, which show a high variability. The proposed methodology was applied to a trial dataset of wintertime PM10 samples - characterised for anhydrosugars, organic, and elemental carbon – collected in the frame of a regional project. The results gave a preliminary estimate of the wood smoke contribution to PM10 and OC in different sites in Lombardy (Northern Italy). [Copyright &y& Elsevier]

Abstract: The concentration of carbonates in atmospheric Particulate Matter (PM) is usually quite low. The surroundings of marble quarries are peculiar sites where the impact of carbonates in PM levels can be significant. We present here the results of a PM10 sampling campaign performed in Carrara (Italy). The town lies between the famous marble quarries and the harbour: about 1000 trucks per day transport marble blocks and debris from the quarries to the harbour passing through the town centre. PM10 was collected on daily basis on PTFE filters analyzed by Energy-Dispersive X-Ray Fluorescence (ED-XRF) and Ion-Chromatography (IC). Carbonate concentration was measured by a non-destructive Infrared Spectroscopy analysis (FT-IR). Time series of elemental (Na–Pb by ED-XRF), ionic (SO4 2−, NH4 + by ion-chromatography) and carbonate (by FT-IR) concentration values were merged in a unique data set and a PMF analysis singled out the major PM10 sources in the area. Marble transportation turned out to be the major pollution source in the town accounting to PM10 for about 36%; this corresponded to a CaCO3 average level of about 8 μg m−3 during working days. The FT-IR analysis was a crucial part of the work and an ad-hoc analytical procedure was specifically set up, calibrated, and tested as described in the text. [Copyright &y& Elsevier]

Abstract: Radiocarbon measurements on the carbonaceous aerosol fractions have been demonstrated as an effective tool for aerosol source apportionment. For these measurements, a new sample preparation facility was installed at the INFN-LABEC laboratory of Florence (Italy). The line was designed to allow the preparation of samples from different carbonaceous fractions: the combustion of the aerosol samples can be performed in helium or oxygen flows, according to thermal sequences. The evolved CO2 is cryogenically trapped and reduced to graphite, which is the target material for following Accelerator Mass Spectrometry (AMS) 14C measurements. This preparation line is described in detail in the paper. As a first step, the line was tested by means of AMS measurements performed on standards to check the reproducibility and the accuracy of the system; moreover, preliminary measurements on the total carbon fraction in aerosol samples were made. Results of these measurements are also reported. [Copyright &y& Elsevier]

Abstract: An example of an integrated approach to assess air pollution threats to cultural heritage in a semi-confined environment is presented in this work, where the monitoring campaign carried out at the Michelozzo''s Courtyard (in Palazzo Vecchio, Florence, Italy) is used as a case study. A wide research project was carried out, with the main aim of obtaining the first quantitative data on air quality and microclimate conditions inside the Courtyard, and, if possible, identifying the main causes of degradation and suggesting appropriate conservation strategies. The investigation adopted a holistic approach involving thermographic measurements on the wall paintings, microclimatic analysis, gaseous pollutant monitoring, atmospheric particles characterisation and dry deposition compositional analysis. Attention was focused on the wall painting depicting the city of Hall because of its anomalous and critical conservation conditions, which are visible at a glance, due to the contrast between a wide darker zone around the central subject of the painting and external lighter areas. [Copyright &y& Elsevier]

Daily time series measurements of elements or compounds are widely used to apportion the contribution of specific sources of particulate matter concentration in the atmosphere. We present results obtained for the urban area of Genoa (Italy) based on several hundred of PM10, PM2.5 and PM1 daily samples collected in sites with different geo-morphological and urbanization characteristics. Elemental concentrations of Na to Pb were obtained through Energy Dispersive X-Ray Fluorescence (ED-XRF), and the contributions of specific sources of particulate matter (PM) concentration were apportioned through Positive Matrix Factorization (PMF). By sampling at different sites we were able to obtain, in each PM fraction, the average and stable values for the tracers of specific sources, in particular traffic (Cu, Zn, Pb) and heavy oil combustion (V, Ni). We could also identify and quote the contamination of anthropogenic PM in “natural” sources (sea, soil dust). Sampling at several sites in the same urban area allowed us to resolve local characteristics as well as to quote average values. [Copyright &y& Elsevier]

Aim: To test the hypothesis that obese individuals may either hyperinflate or deflate the lung when exercising. In both cases breathlessness is an inescapable consequence. Methods: Ventilatory variables, end-expiratory lung volume and end-inspiratory lung volume, and dyspnoea score (Borg scale) were studied in 20 class II-III obese subjects and 14 healthy controls during incremental symptom-limited cycle exercise. Results: Ventilation increased with increasing work rate, in obese and in control subjects; most obese subjects had to increase end-expiratory lung volume to escape from flow limitation; in contrast, like controls, a few subjects deflated the lung on heavy-to-peak exercise. Dyspnoea was equal in degree at anaerobic threshold and peak exercise in obese as in control subjects, and in obese who hyperinflated as in those who deflated the lung. In particular, end-expiratory lung volume at baseline ( r = −0.84, P = 0.04) was negatively correlated with changes in Borg score in obese who did not hyperinflate: the lower the former the higher the latter. On the other hand, tidal volume ( r = 0.54, P = 0.045) and decrease in inspiratory reserve volume ( r = 0.59, P = 0.028) were positively correlated with the Borg score in obese subjects who hyperinflated. No other independent variable correlated with the Borg score. Conclusions: We conclude that not all obese subjects had to increase end-expiratory lung volume on heavy-to-peak exercise. Changes in dyspnoea for unit changes in ventilation were similar in obese who did hyperinflate as well as in those who did not, suggesting that the increase in respiratory neural drive, associated with an increase in ventilation, is an important source of dyspnoea in obese as well as in control subjects. [ABSTRACT FROM AUTHOR]

Sub-micron sized particles are of increasing concern owing to their effects on human health and on the environment. Up to now there are still very few studies on PM1 (i.e. particulate matter with aerodynamic diameter smaller than 1μm) chemical characterisation; the sub-micron sized fraction is not under regulations although it is of interest because it is almost exclusively associated to anthropogenic sources. To perform the first large-scale assessment of sub-micron sized aerosol concentrations, composition and sources, two monitoring campaigns at three urban sites in Italy were carried out during the wintertime and summertime of 2004. Chemical characterisation (elements, soluble ionic fraction, elemental and organic carbon) was carried out on PM1 samples: major contributions were due to organic matter (about 30% in summer and 50% in winter) and ammonium sulphate (about 10% in winter and 40% in summer). During the cold season, nitrates also contributed up to 30% in Milan (lower contributions were registered at the other two urban sites). Chemical mass closure was achieved with an unaccounted mass in the range 14–22%. Positive Matrix Factorisation (PMF) was applied to identify the major sub-micron sized particles’ sources. [Copyright &y& Elsevier]

The wall paintings of the Michelozzo’s Courtyard (XVI century) at the main entrance of Palazzo Vecchio in Florence are in an advanced state of degradation. With the aim of understanding the environmental conditions in the Courtyard a wide research project has been instigated. In this study, the fine and coarse fractions of the PM10 have been collected by a ‘streaker’ sampler with an hourly resolution and then analysed by PIXE at the 3MV tandetron accelerator in Florence; the first results will be presented here. [Copyright &y& Elsevier]

Abstract: The composition of particulate matter near a large steel plant, located inside the town of Genoa (Italy), has been studied since July 2004. Several instruments have been used: a sequential sampler, operated on a daily basis and a two-stage continuous streaker sampler. An optical particle counter (OPC) provided the aerosol size distribution with a 1-min time resolution. PIXE and ED-XRF analysis were performed on the aerosol samples. In particular, the streaker frames were analyzed by PIXE at the new external proton beam facility of INFN-Florence whereas the daily filters were measured by ED-XRF in Genoa. We present here results obtained in a part of the campaign when all the above quoted devices have been operated simultaneously. [Copyright &y& Elsevier]

Abstract: The particulate matter (PM) concentration and composition, the PM10, PM2.5, PM1 fractions, were studied in the urban area of Genoa, a coastal town in the northwest of Italy. Two instruments, the continuous monitor TEOM and the sequential sampler PARTISOL, were operated almost continuously on the same site from July 2001 to September 2004. Samples collected by PARTISOL were weighted to obtain PM concentration and then analysed by PIXE (particle induced X-ray emission) and by ED-XRF (energy dispersion X-ray fluorescence), obtaining concentrations for elements from Na to Pb. Some of the filters used in the TEOM microbalance were analysed by ED-XRF to calculate Pb concentration values averaged over 7–30d periods. [Copyright &y& Elsevier]

The paper presents methodological innovations introduced in the characterisation of urban aerosol collected in Italy in a recent campaign. Two complementary ion beam analysis (IBA) techniques were used to analyse Nuclepore filters used in continuous streaker samplers to collect airborn particles in four Italian towns. Na to Pb elemental concentrations were obtained by particle induced X-ray emission (PIXE), while time of flight secondary ion mass spectrometry (ToF-SIMS) produced, on the same samples, time trends for several elements and molecular fragments. In addition, light attenuation measurements were used as a tracer for black carbon. The data produced by these three techniques was merged into a unique data set to address the characterisation of particulate matter sources. Correlations between elemental concentration trends (PIXE) and relative trends for molecular fragments (ToF-SIMS) and black carbon (light attenuation) have been studied by cluster and principal component analysis. [Copyright &y& Elsevier]

Microcalcifications (μCas) are often early signs of breast cancer. However, detecting them is a difficult visual task and recognizing malignant lesions is a complex diagnostic problem. In recent years, several research groups have been working to develop computer-aided diagnosis (CAD) systems for X-ray mammography. In this paper, we propose a method to detect and classify microcalcifications. In order to discover the presence of μCas clusters, particular attention is paid to the analysis of the spatial arrangement of detected lesions.A fractal model has been used to describe the mammographic image, thus, allowing the use of a matched filtering stage to enhance microcalcifications against the background. A region growing algorithm, coupled with a neural classifier, detects existing lesions. Subsequently, a second fractal model is used to analyze their spatial arrangement so that the presence of microcalcification clusters can be detected and classified.Reported results indicate that fractal models provide an adequate framework for medical image processing; consequently high correct classification rates are achieved. [Copyright &y& Elsevier]

The composition of particulate matter in the atmosphere of four major italian towns (Florence, Genoa, Milan and Naples) has been studied with hourly resolution by means of ion beam analysis (IBA) techniques and statistical methods. The aerosol has been collected simultaneously in the four towns during the first weeks of year 2001, by two-stage continuous streaker samplers, which separate and collect the PM10 particulate matter in two fractions. The hourly concentrations in air of about 20 elements have been extracted in the fine and coarse fractions of PM10 by particle induced X-ray (and gamma-ray) emission, PIXE (and PIGE), analysis of about 2700 hourly samples. The coupled use of streaker samplers and IBA techniques made distinguishable time patterns typical of urban environments as well as fast and occasional episodes. Absolute principal component factor analysis (APCFA) and other statistical approaches have been used to obtain a sintetic apportionment of the sources of particulate matter. [Copyright &y& Elsevier]

The composition of particulate matter in the atmosphere of four major Italian towns (Florence, Genoa, Milan and Naples) has been studied with the extensive application of IBA techniques. The aerosol has been collected simultaneously in the four towns during the first weeks of year 2001, by two-stage continuous streaker samplers, which provide the separation of the particulate matter in two fractions. The concentrations in air of about 20 elements, and the total particulate mass, have been extracted in the PM2.5 and PM10 fractions with hourly resolution by PIXE, PIGE and optical analyses of about 2700 samples. IBA analyses have been performed at the 3 MeV external proton beam of the INFN accelerator facility at the University of Florence. [Copyright &y& Elsevier]