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This study aims to investigate the air quality in primary school placed in district of Taranto (south of Italy), an area of high environmental risk because of closeness between large industrial complex and urban settlement. The chemical characterization of PM2.5 was performed to identify origin of pollutants detected inside school and the comparison between indoor and outdoor levels of PAHs and metals allowed evaluating intrusion of outdoor pollutants or the existence of specific indoor sources. The results showed that the indoor and outdoor levels of PM2.5, BaP, Cd, Ni, As, and Pb never exceeded the target values issued by World Health Organization (WHO). Nevertheless, high metals and PAHs concentrations were detected especially when school were downwind to the steel plant. The I/O ratio showed the impact of outdoor pollutants, especially of industrial markers as Fe, Mn, Zn, and Pb, on indoor air quality. This result was confirmed by values of diagnostic ratio as B(a)P/B(g)P, IP/(IP + BgP), BaP/Chry, and BaP/(BaP + Chry), which showed range characteristics of coke and coal combustion. However, Ni and As showed I/O ratio of 2.5 and 1.4, respectively, suggesting the presence of indoor sources. [ABSTRACT FROM AUTHOR]

A high time-resolved monitoring campaign of bulk deposition of PAHs and metals was conducted near the industrial area and at an urban background site in province of Taranto (Italy) in order to evaluate the impact of the biggest European steel plant. The deposition fluxes of the sum of detected PAHs at the industrial area ranged from 92 to 2432 ng m-2 d-1. In particular the deposition fluxesofBaP, BaA, and BkFwere, on average, 10, 14, and 8 times higher than those detected at the urban back ground site, respectively. The same finding was for metals. The deposition fluxes of Ni (19.8 µgm-2 d-1) andAs (2.2 µgm-2 d-1) at the industrial site were about 5 times higher than those at the urban background site, while the deposition fluxes of Fe (57 mg m-2 d-1) and Mn (1.02 mg m-2 d-1) about 31 times higher. Precipitation and wind speed played an important role in PAH deposition fluxes. Fe and Mn fluxes at the industrial site resulted high when wind direction favored the transport of air masses from the steel plant to the receptor site. The impact of the industrial area was also confirmed by IP/(IP + BgP), IP/BgP, and BaP/BgP diagnostic ratios. [ABSTRACT FROM AUTHOR]

The atmosphere is a carrier on which some natural and anthropogenic organic and inorganic chemicals are transported, and the wet and dry deposition events are the most important processes that remove those chemicals, depositing it on soil and water. A wide variety of different collectors were tested to evaluate site-specificity, seasonality and daily variability of settleable particle concentrations. Deposition fluxes of POPs showed spatial and seasonal variations, diagnostic ratios of PAHs on deposited particles, allowed the discrimination between pyrolytic or petrogenic sources. Congener pattern analysis and bulk deposition fluxes in rural sites confirmed long-range atmospheric transport of PCDDs/Fs. More and more sophisticated and newly designed deposition samplers have being used for characterization of deposited mercury, demonstrating the importance of rain scavenging and the relatively higher magnitude of Hg deposition from Chinese anthropogenic sources. Recently biological monitors demonstrated that PAH concentrations in lichens were comparable with concentrations measured in a conventional active sampler in an outdoor environment. In this review the authors explore the methodological approaches used for the assessment of atmospheric deposition, from the analysis of the sampling methods, the analytical procedures for chemical characterization of pollutants and the main results from the scientific literature. [ABSTRACT FROM AUTHOR]

A weekly monitoring campaign of volatile organic compounds (VOC), with single sampling of 24 h, was carried out in non-residential indoor environments such as libraries, pharmacies, offices, gymnasiums, etc., in order to evaluate the VOC concentrations to which people are exposed. Moreover, an outdoor sample was coupled to each indoor site to point out the influence of indoor sources. They were sampled with Radiello® diffusive samplers for thermal desorption and analyzed by GC-MS. As already described in other papers, the VOC levels of most of the indoor sites were higher than that observed in the corresponding outdoor sites. For example, some sites showed a level of pollution that is ten times higher than their corresponding outdoor site. The monitored environments that had higher concentrations of the investigated VOC were the pharmacies, a newspaper stand, a copy center, and the coffee shops. Analysis of the weekly average concentrations of each pollutant and the use of literature allowed pointing out some site-specific characteristics that singled out possible sources of VOC. These results were verified analyzing the indoor-outdoor ratio (I/O) too. Newspaper stands were characterized by very high concentrations of toluene and pharmacies were characterized by high concentrations of aromatic compounds. Practical Implications Indoor air pollution caused by volatile organic compounds (VOC) might affect human health at home as well as in public and commercial buildings. The main VOC sources in indoor environments are human activities, personal care products, smoking, house cleaning products, building products, and outside pollution. To preserve human health it is necessary to evaluate the average concentrations of VOC to which people are exposed and to identify the main sources of indoor pollution by means of suitable indoor monitoring campaigns in several environments. These investigations allow pointing out the characteristic critical situations of some indoor environments or some other types of environments. [ABSTRACT FROM AUTHOR]

The core structure of the cell-wall lipooligosaccharide (LOS) fraction of an Antarctic Gram-negative bacterium, Pseudoalteromonas haloplanktis TAC 125 strain, was determined to be deacetylated alditols. These were obtained from native LOS fraction by O-deacylation, dephosphorylation, reduction and finally N-deacylation. Two novel structures were detected, the more highly represented molecule consisting of the following hexasaccharide chain: α‐d‐ManpNH2-(1→3)‐β‐d‐Galp-(1→4)‐α‐l‐glycero‐d‐manno‐Hepp‐(1→5)‐α‐d‐Kdo‐(2→6)‐β‐d‐GlcpNH2‐(1→6)‐d‐GlcNH2(ol) while the corresponding pentasaccharide, lacking the ManpNH2 residue, was less abundant. To the best of our knowledge, the structural investigation presented here, mainly performed by NMR and MS methods, is the first report of the lipopolysaccharide fraction of a psychrophilic bacterium. [ABSTRACT FROM AUTHOR]

Examines the gene encoding aspartate aminotransferase from psychrophilic bacterium Pseudoalteromonas haloplanktis in Escherichia coli. Stability of thermal proteins in tryptophan fluorescence and amide ellipticity; Affinity of recombinant protein for both amino acid and 2-oxo-acid substrates; Steps in the catalytic mechanism in external aldimine.

Microorganisms encounter diverse stress conditions in their native habitats but also during fermentation processes, which have an impact on industrial process performance. These environmental stresses and the physiological reactions they trigger, including changes in the protein folding/secretion machinery, are highly interrelated. Thus, the investigation of environmental factors, which influence protein expression and secretion is still of great importance. Among all the possible stresses, temperature appears particularly important for bioreactor cultivation of recombinant hosts, as reductions of growth temperature have been reported to increase recombinant protein production in various host organisms. Therefore, the impact of temperature on the secretion of proteins with therapeutic interest, exemplified by a model antibody Fab fragment, was analyzed in five different microbial protein production hosts growing under steady-state conditions in carbon-limited chemostat cultivations. Secretory expression of the heterodimeric antibody Fab fragment was successful in all five microbial host systems, namely Saccharomyces cerevisiae, Pichia pastoris, Trichoderma reesei, Escherichia coli and Pseudoalteromonas haloplanktis. In this comparative analysis we show that a reduction of cultivation temperature during growth at constant growth rate had a positive effect on Fab 3H6 production in three of four analyzed microorganisms, indicating common physiological responses, which favor recombinant protein production in prokaryotic as well as eukaryotic microbes., (Copyright © 2010 American Institute of Chemical Engineers (AIChE).)