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Physical and optical properties of atmospheric aerosols collected by using a high resolution (1.5 nm) spectroradiometer (spectral range 400–800 nm), a 13-stage Dekati Low Pressure Impactor (size range 30 nm–10 μm), and an AE31 Aethalometer (7 wavelenghts from 370 nm to 950 nm), have been examined in a semi-rural site in Southwest Italy (Tito Scalo, 40°35' N, 15°41' E, 750 m a.s.l.). In particular, daily averaged values of AOD and Ångström turbidity parameters from radiometric data together with mass-size distributions from impactor data and Black Carbon (BC) concentrations have been analyzed from May to October 2008. Furthermore, by inverting direct solar radiances, aerosol columnar number and volume size distributions have been obtained for the same period. The comparison of different observation methods, allowed to verify if, and in what conditions, changes in aerosol properties measured at ground are representative of columnar properties variations. Agreement between columnar and in-situ measurements has been obtained in case of anthropogenic aerosol loading, while in case of Saharan dust intrusions some discrepancies have been found when dust particles were located at high layers in the atmosphere (4–8 km) thus affecting columnar properties more than surface ones. For anthropogenic aerosols, a good correlation has been confirmed through the comparison of fine aerosol fraction contribution as measured by radiometer, impactor and aethalometer, suggesting that, in this case, the particles are more homogeneously distributed over the lower layers of atmosphere and columnar aerosol optical properties are dominated by surface measured component.

Eight measurement campaigns for the characterization of atmospheric aerosol properties were conducted from 2001 until 2008 at five sites located in the Western Mediterranean basin. Radiometric measurements were used to obtain Aerosol Optical Depth, Ångström parameters, and aerosol size distributions, allowing differentiation of background conditions from anthropogenic, marine, or Saharan dust aerosol advection. The analysis was focused on the study of optical and physical properties variation of atmospheric aerosols under Saharan outbreaks. Dust-affected data were analysed all together, independently from the measurements site, thus allowing the highlighting of similarities and differences among them. The scatter-plot Ångström exponent versus AOD at 780 nm shows a correlation among all dust data, while an overlapping region with no-dust data reveals the simultaneous presence of mineral, anthropogenic, and marine particles. Daily averaged volume size distributions can be unimodal or bimodal functions and one three-modal distribution, with a coarse mode generally prevailing. Finally, considering the ratio of small/large particles 𝑛𝑠/𝑛𝑙 and plotting the corresponding histogram for all dust data, a sharp frequency distribution is obtained with 89% of data in the range 5–65, while 89% of no-dust data extend from 5 to 135, in spite of different sources, pathways, and arrival sites.

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In this study, field measurement was conducted using an integrated online monitoring system to characterize heterogeneous properties and light absorption of refractory black carbon (rBC). rBC particles are mainly from the incomplete combustion of carbonaceous fuels. With the data collected from a single particle soot photometer, thickly coated (BC kc ) and thinly coated (BC nc ) particles are characterized with their lag times. With different responses to the precipitation, a dramatical decline of 83 % in the number concentration of BC kc is shown after rainfall, while that of BC nc decreases by 39 %. There is a contrast in core size distribution that BC kc is always with larger particle sizes but has smaller core mass median diameters (MMD) than BC nc . The mean rBC-containing particle mass absorption cross-section (MAC) is 6.70 ± 1.52 m 2  g -1 , while the corresponding rBC core is 4.90 ± 1.02 m 2  g -1 . Interestingly, there are wide variations in the core MAC values which range by 57 % from 3.79 to 5.95 m 2  g -1 , which are also closely related to those of the whole rBC-containing particles with a Pearson correlation of 0.58 (p < 0.01). Errors would be made if we eliminate the discrepancies and set the core MAC as a constant when calculating absorption enhancement (E abs ). In this study, the mean E abs is 1.37 ± 0.11 while the source apportionment shows that there are five contributors of E abs including secondary aging (37 %), coal combustion (26 %), fugitive dust (15 %), biomass burning (13 %) and traffic-related emissions (9 %). Secondary aging is found to be the highest contributor due to the liquid phase reactions in formations of secondary inorganic aerosol. Our study characterizes property diversities and provides insights into the sources impacting the light absorption of rBC and will be helpful for controlling it in the future., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)

A multi-parametric experimental campaign was performed in Agri Valley (Basilicata, southern Italy) from July 2017 to January 2018. The investigated area, though basically rural and devoted to agricultural activities, hosts a huge on-shore oil reservoir, i.e. Centro Olio Val d'Agri (COVA), bringing substantial environmental modifications and impacts to the district landscape. Daily concentrations of PM 1 aerosol samples, Equivalent Black Carbon and number size distributions were evaluated. Chemical aerosol speciation based on elemental and ion analyses were carried out and source apportionment by Positive Matrix Factorization (PMF) was applied to reconstruct PM 1 source profile. The most significant emission sources found are torches from the oil treatment facility (37 % w/w), an unresolved factor constituted by soil resuspension, Saharan dust, and biomass burning (24 % w/w), ammonium sulphate (23 % w/w), emissions from the oil desulfurization (Claus process) (13 % w/w), and traffic + road dust (3 % w/w). SEM analysis on PM 1 single particles allowed to confirm the finding from PMF including the occurrence of elemental sulfur associated with the Claus process. The novelty of the present study consists in the identification of this latter fingerprint., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier B.V. All rights reserved.)

Soot particles form during combustion of carbonaceous materials and impact climate and air quality. When freshly emitted, they are typically fractal-like aggregates. After atmospheric aging, they can act as cloud condensation nuclei, and water condensation or evaporation restructure them to more compact aggregates, affecting their optical, aerodynamic, and surface properties. Here we survey the morphology of ambient soot particles from various locations and different environmental and aging conditions. We used electron microscopy and show extensive soot compaction after cloud processing. We further performed laboratory experiments to simulate atmospheric cloud processing under controlled conditions. We find that soot particles sampled after evaporating the cloud droplets, are significantly more compact than freshly emitted and interstitial soot, confirming that cloud processing, not just exposure to high humidity, compacts soot. Our findings have implications for how the radiative, surface, and aerodynamic properties, and the fate of soot particles are represented in numerical models.

Simultaneous measurements of columnar aerosol microphysical and optical properties, as well as PM 2.5 chemical compositions, were made during two types of spring pollution episodes in Tianjin, a coastal megacity of China. The events were investigated using field observations, satellite data, model simulations, and meteorological fields. The lower Ångström Exponent and the higher aerosol optical depth on 29 March, compared with the earlier event on 26 March, implied a dominance of coarse mode particles - this was consistent with the differences in volume-size distributions. Based on the single scattering spectra, the dominant absorber (at blue wavelength) changed from black carbon during less polluted days to brown carbon on 26 March and dust on 29 March. The concentrations of major PM 2.5 species for these two episodes also differed, with the earlier event enriched in pollution-derived substances and the later with mineral dust elements. The formation mechanisms of these two pollution episodes were also examined. The 26 March episode was attributed to the accumulation of both local emissions and anthropogenic pollutants transported from the southwest of Tianjin under the control of high pressure system. While the high aerosol loading on 29 March was caused by the mixing of transported dust from northwest source region with local urban pollution. The mixing of transported anthropogenic pollutants and dust with local emissions demonstrated the complexity of springtime pollution in Tianjin. The synergy of multi-scale observations showed excellent potential for air pollution study., (Copyright © 2017 Elsevier B.V. All rights reserved.)

Aerosol composition and properties variation under the advection of different air masses were investigated, as case studies, by contemporary measurements over the atmospheric column and at the ground in a semi-rural site in South Italy. The absence of local strong sources in this area allowed to characterize background aerosol and to compare particle mixing effects under various atmospheric circulation conditions. Aerosol optical depth (AOD) and Ǻngström parameters from radiometric measurements allowed the detection and identification of polluted, dust, and volcanic atmospheric conditions. AODs were the input for a suitable model to evaluate the columnar aerosol composition, according to six main atmospheric components (water-soluble, soot, sea salt accumulation, sea salt coarse, mineral dus,t and biological). Scanning electron microscope (SEM) analysis of particulate sampled with a 13-stage impactor at the ground showed not only fingerprints typical of the different air masses but also the effects of transport and aging on atmospheric particles, suggesting processes that changed their chemical and optical properties. Background columnar aerosol was characterized by 72% of water-soluble and soot, in agreement with ground-based findings that highlighted 60% of contribution from anthropogenic carbonate particles and soot. In general, a good agreement between ground-based and columnar results was observed. Under the advection of trans-boundary air masses, water-soluble and soot were always present in columnar aerosol, whereas, in variable percentages, sea salt and mineral particles characterized both dust and volcanic conditions. At the ground, sulfates characterized the amorphous matrix produced in finer stages by the evaporation of solutions of organic and inorganic aerosols. Sulfates were also one of the key players involved in heterogeneous chemical reactions, producing complex secondary aerosol, as such clay-sulfate internally mixed particle externally mixed with soot chains.

The paper presents a novel methodology to retrieve the foreign-broadened water vapor continuum absorption coefficients in the spectral range 240 to 590 cm(-1) and is the first estimation of the continuum coefficient at wave numbers smaller than 400 cm(-1) under atmospheric conditions. The derivation has been accomplished by processing a suitable set of atmospheric emitted spectral radiance observations obtained during the March 2007 Alps campaign of the ECOWAR project (Earth Cooling by WAter vapor Radiation). It is shown that, in the range 450 to 600 cm(-1), our findings are in good agreement with the widely used Mlawer, Tobin-Clough, Kneizys-Davies (MT CKD) continuum. Below 450 cm(-1) however the MT CKD model overestimates the magnitude of the continuum coefficient.

The paper studies, with the help of HPLC-DAD-MS/MS technique, the hydrolytic and photoinduced degradation processes that take place in aqueous solutions of tribenuron methyl, both when preserved in the dark and when undergoing solar box irradiation under conditions that simulate sun light. The results indicate that the degradation products formed by hydrolysis alone and by photoirradiation are the same, but kinetics of the hydrolysis reaction is much slower. The degradation products are identified as 2-methoxy-4-methylamino-6-methyl-1,3,5-triazine (P1), methyl 2-aminosulfonylbenzoate (P2), and saccharin (P3) and quantified. Ecotoxicological biotests performed on 0.1 microg L(-1) photoirradiated solutions of the herbicide give a border line toxicity situation comparable to that of the precursor and indicate that the herbicide is characterized by low persistence in the environment, as required. Its degradation, however, does not lead to mineralization but to the formation of products of comparable toxicity. To evaluate the matrix effects, the photodegradation of the herbicide is also studied in the presence of rice paddy waters: the process is slower than in ultrapure water but leads to the same products. Experiments performed for comparison by irradiating ultrapure water solutions with UV lamp (254 nm) show that the degradation process is not only faster with respect to sunlight, but gives a different pathway, without in anyway leading to mineralization.

We evaluate the spectral quality, radiometric noise, and retrieval performance of a Fourier transform infrared spectrometer, which has been developed for recording spectrally resolved observations in a region of the spectrum which is important both for the science of Earth's climate and applications, such as the remote sensing of temperature and atmospheric gas species. This spectral region extends from 100 to 1600 cm(-1) and encompasses the two fundamental, rotation and vibration, absorption bands of water vapor. The instrument is a customized version of a Bomem AERI (Atmospheric Emitted Radiance Interferometer) spectrometer, whose spectral coverage has been extended in the far infrared with the use of uncooled pyroelectric detectors. Retrieval examples for water vapor and temperature profiles are shown, which also allow us to intercompare the retrieval performance of both H(2)O vibration and rotation bands.

The Carlo Alberto Canal connects Bormida and Tanaro rivers in Piedmont (ITALY). It was created for irrigation purposes but since its waters are suspected to be polluted, a sampling campaign was performed by the ARPA of Alessandria. The physico-chemical parameters analysed along 3 years (1998-2000) were investigated by multivariate chemometric methods. PCA showed that the waters situation depends heavily on the sampling period. Also a Kohonen self-organising map confirmed the clustering observed, providing insights into the causes of the clusterisation. New samplings are now being performed and a larger set of environmental variables is determined on each sample.

The aim of this study was to evaluate age, plasmatic renin activity (PRA), plasma aldosterone levels and the total quantity of urinary catecholamines (TOT. UR. CAT.) in a large population of out-patients suffering from essential arterial hypertension (EAH). A total of 986 patients were examined (540 women and 426 men aged between 15 and 87 years) suffering form slight or moderate EAH (WHO stage 1-2). After a wash-out period of two weeks, systolic and diastolic arterial pressure was measured together with heart rate in clino- and orthostatism. Blood samples were collected to determine PRA and plasma aldosterone, and lastly a 24-hour urine collection was made to measure the total quantity of catecholamines. It emerged that there was a significant increase in systolic pressure, whereas heart rate and PRA diminished significantly when correlated with age; diastolic pressure was also considerably lower, but did not reach statistical significance. Moreover, it was found that there was a significant positive correlation between PRA and TOT. UR. CAT., whereas no correlation was found between age and plasma aldosterone and between blood pressure and the various endocrine parameters examined. These data confirm the changes in the biological, hemodynamic and endocrine profiles observed in elderly hypertensive patients in comparison to young hypertensive patients, and suggests that age may be an important predictive factor of the activity of both the renin-angiotensin and sympathetic nervous system which appear to be closely connected and gradually attenuated by age.

The following parameters were studied in a group of patients suffering from essential arterial hypertension complicated by chronic renal insufficiency (CRI), mean age = 64.31 +/- 1.84, with creatinine clearance (CrC) ranging between 30 and 60 ml/min: blood pressure (systolic and diastolic arterial pressure), heart rate, plasmatic renin activity (PRA), plasma levels of aldosterone (ALDO) both in clino- and orthostatism, as well as some metabolic parameters. All parameters were compared with those in a group of age- and sex-matched patients with slight or moderate essential arterial hypertension. Before starting the study all patients completed a wash-out period of one week to annual the effects of other drugs which might interfere with the RAA system. PRA levels were within the norm, whereas plasma levels of ALDO were high both in clino- and orthostatism. ALDO levels were also found to be inversely correlated with those of CrC. From these data it emerges that hyperaldosteronism, as observed in these patients with CRI, is a relatively reliable marker of the extent of CRI and may occur independently of the activation of the RAA system, given that other factors, such as orthostatic stimulation, alterations in the acid-base equilibrium, and the degree of aldosterone hepatic and urinary clearance, contribute to its pathogenesis.

Etozolin, a new diuretic agent, has shown a dose-dependent diuretic and saluretic effect in both experimental and clinical studies. Etoxolin, when compared to furosemide or thiazides, exerts a similar effect on urinary excretion of water and Na+, but induces a lower urinary K+ and Cl- excretion and a smaller activation of the renin-angiotensin-aldosterone system. Furthermore, the E series of the prostaglandin system seems to play a role in the mechanism of action of the drug. Seven uncomplicated hypertensive patients were included in this double blind, placebo controlled study, according to a latin square design. Each patient received three single oral doses of etozolin (200 mg, 400 mg, 600 mg), of chlorthalidone (25 mg, 50 mg, 75 mg) and one dose of placebo. Etozolin and chlorthalidone caused a similar, dose-dependent antihypertensive and diuretic effect. However, several haemodynamic and metabolic differences were observed between the two drugs. Etozolin, unlike chlorthalidone, caused no increase of heart rate, no decrease of serum K+ levels and a marked rise plasma PGE2. Moreover, etozolin caused a significantly smaller decrease of serum Na levels compared to chlorthalidone, and a significantly lower increase of supine and standing PRA, of plasma aldosterone and of the urinary excretion of Na and K. These results confirm that the acute antihypertensive and diuretic activity of etozolin occur with little involvement of the RAA system and with a significant but still unclear activation of the prostaglandin system.

Calcitonin gene-related peptide (CGRP) is a neuropeptide with potent cardiovascular effects that include positive inotropic and chronotropic actions systemic vasodilation, and hypotension in animals and in man. The mechanism of action of CGRP is still, however, not clear, and in particular it is not known whether vasodilation by CGRP occurs by changes in cutaneous or in muscular blood flow, or both. The aim of the study was, therefore, to evaluate the cutaneous and muscular blood flow, at rest and after ischemic test, induced by an IV bolus 25 micrograms human CGRP infusion in 5 healthy normotensive volunteers, using a strain gauge plethysmographic procedure with venous occlusion. Human CGRP provoked a transient but significant decrease in systolic and diastolic blood pressure, associated with tachycardia, marked flushing, a significant increase in plasma noradrenaline, adrenaline, and cyclic AMP levels, and a slight, but significant, decrease in serum total calcium. Moreover, a significant increase in the carpal cutaneous blood flow at rest was observed, with no significant change in the lower extremity muscular blood flow at rest and after ischemic test. Finally human CGRP produced a significant increase in the venous partial O2 pressure and in the hematocrit and a significant decrease in the venous partial CO2 pressure. The results of the present study confirm the acute cardiovascular and metabolic effects of CGRP. In fact, hypotension, tachycardia, flushing, and the increased cutaneous blood flow indicate a systemic vasodilation by the neuropeptide, with a secondary sympathetic response, as documented by the augmented catecholamine and cyclic AMP plasma levels.

Eleven centers in Tuscany, Italy, recruited 96 patients (aged 21-75 years) with mild-to-moderate essential hypertension [diastolic blood pressure (DBP) 95-115 mm Hg; systolic blood pressure (SBP) less than or equal to 200 mm Hg]. After a 4-week, single-blind, placebo run-in period, patients received lacidipine 4 mg once daily. If blood pressure was not controlled after 1 month (control = DBP less than or equal to 90 mm Hg, or less than or equal to 95 mm Hg if reduced by greater than or equal to 15 mm Hg from baseline), the dose was increased to lacidipine 8 mg once daily. Atenolol 50 mg once daily was added after 2 months' monotherapy, if required for blood pressure control. The study continued for 13 months. About 40% of patients were titrated to 8 mg lacidipine; only 7% required addition of atenolol. Lacidipine significantly reduced blood pressure, with 84% of patients showing control of pressure values 24 h after the previous dose on completion of 5 months' monotherapy (63% controlled with lacidipine 4 mg/day; 21% with lacidipine 8 mg/day). There was no clinically relevant difference in the first-dose effect between the two doses of lacidipine (4 mg and 8 mg); both smoothly reduced blood pressure, with maximum effect after 2 h. Lacidipine was well tolerated. Adverse events were those expected with dihydropyridines, were mainly mild and occurred early, disappearing without discontinuation of treatment. Results indicate that 4-8 mg of lacidipine, administered once daily, is effective and well tolerated in mildly to moderately hypertensive patients.

The incidence of district (cardiac, cerebral, renal) and systemic vascular complications was studied in a population of 3992 hypertensive in-patients during the period from 1984 to 1988. The total number of male hypertensive patients was always higher (2355) than that of female hypertensive patients (1637). From the analysis of results it appears that 11.01% of male hypertensive patients and 15.85% of female hypertensive patients were diagnosed as being affected by uncomplicated essential arterial hypertension, whereas 88.97% of male and 84.12% of female hypertensive patients suffered from arterial hypertension with varying percentages of cardiac, cerebral, renal or systemic-type atheroarteriosclerotic complications. The prevalence of the male sex was particularly evident in the case of cardiac complications. Given the peak incidence of the various types of complications when analysed by decade of age, an earlier incidence of cardiac and renal complications was found in male hypertensive patients which anticipates the complications found in female hypertensive patients by approximately one decade. Lastly, the paper underlines the social importance of essential arterial hypertension and the need to develop efficacious primary and secondary prevention in order to reduce the incidence of complications which today represent the most severe aspect of hypertension.

Given the significance of the calcium ion in the pathogenesis of essential arterial hypertension, blood levels of total and ionised calcium, phosphorus, parathormone, blood renin activity as well as urinary calcium and phosphorus were assayed in a group of hypertensives and a comparable control group with normal blood pressure. The results showed reduced ionised calcium in the blood of the hypertensives together with hyperparathyroidism and increased calciuria. In addition, the link between parathormone and mean blood pressure levels suggests that parathormone itself play a primary role in the genesis of high blood pressure. Finally the connection between renin activity in the plasma and ionised calcium in the serum suggests that the two hormone systems are closely linked and may interact via the calcium ion.

The antihypertensive efficacy of a combination of calcium-channel blockers and angiotensin-converting-enzyme (ACE) inhibitors in severe primary hypertension is well known, but a synergistic action of this drug combination in mild to moderate primary hypertension is still not established. Therefore, the aim of the present study was to evaluate the efficacy and tolerability of monotherapy with nitrendipine (20 mg) or captopril (100 mg), and of their combination (nitrendipine 10 mg plus captopril 50 mg), in patients suffering from mild to moderate primary hypertension, according to a single-blind, randomized, placebo-controlled design. After the first 4-week monotherapy period, both nitrendipine and captopril induced a significant decrease in systolic and diastolic blood pressure (BP) (p less than 0.001). Furthermore, nitrendipine caused a significant increase in heart rate (HR), while no change in HR was observed in patients treated with captopril. Several side effects were observed, both in the nitrendipine-treated patients (facial flushing, headache, malleolar edema) and in the captopril-treated patients (initial hypotension, dizziness, gastrointestinal disorders). However, these side effects were mild and were well tolerated. In the second combined 4-week therapy period, systolic and diastolic BP of patients treated with 10 mg nitrendipine combined with 50 mg captopril continued to decrease to a degree significantly lower (p less than 0.001) than that observed at the end of the monotherapy period. Simultaneously, no change in HR values occurred when compared to basal values. Furthermore, the incidence and intensity of some side effects observed during the combined therapy period were lower than those of the monotherapy period.(ABSTRACT TRUNCATED AT 250 WORDS)

Acute cardiovascular and renal effects of 25 micrograms IV human calcitonin gene-related peptide (hCGRP) have been studied in four normotensive and untreated subjects, in the absence and the presence of indomethacin, a prostaglandin synthesis-blocking agent. Intravenous infusion of hCGRP, alone, caused a transient but significant increase in heart rate (HR), hypotension, and facial flushing. Along with these effects, a positive inotropic action of hCGRP was documented by a noninvasive poligraphy. Furthermore, a significant increase in the catecholamines (norepinephrine and epinephrine), in the cyclic nucleotide (cyclic AMP and cyclic GMP) plasma levels, and a small decrease in total calcium with no change in inorganic phosphorus serum levels, occurred. Also acute renal hCGRP induced effects were observed, as a significant increase in urinary volume and in the urinary calcium, sodium, potassium, and chloride excretion. Indomethacin did not affect all the cardiovascular, metabolic, and renal hCGRP-induced effects. These results are in agreement with the hypothesis that hCGRP acts on the heart, vessels, and kidney, directly or indirectly, by the mediation of other vasodilating agents or systems excluding the prostaglandin system.

Ceftazidime was used in 19 patients at high risk owing to severe impairment of natural defense systems. The therapeutic efficacy and adverse reactions produced by cephalosporin, as evaluated on the basis of the results of clinical investigations and laboratory tests, were regarded as positive.