644 research outputs found
CleAir monitoring system for particulate matter. A case in the Napoleonic Museum in Rome
Monitoring the air particulate concentration both outdoors and indoors is becoming a more relevant issue in the past few decades. An innovative, fully automatic, monitoring system called CleAir is presented. Such a system wants to go beyond the traditional technique (gravimetric analysis), allowing for a double monitoring approach: the traditional gravimetric analysis as well as the optical spectroscopic analysis of the scattering on the same filters in steady-state conditions. The experimental data are interpreted in terms of light percolation through highly scattering matter by means of the stretched exponential evolution. CleAir has been applied to investigate the daily distribution of particulate matter within the Napoleonic Museum in Rome as a test case
Geopolymer composites for potential applications in cultural heritage
A new class of geopolymer composites, as materials alternative to traditional binders, was synthesized and its potentialities as restoration material in Cultural Heritage has been explored. This material has been prepared through a co-reticulation reaction in mild conditions of a metakaolin-based geopolymer inorganic matrix and a commercial epoxy resin. The freshly prepared slurry displays a consistency, workability and thixotropic behavior that make it suitable to be spread on different substrates in restoration, repair and reinforcement actions, even on walls and ceilings. Applicability and compatibility tests on tuff and concrete substrates were carried out and the microstructure of the samples in correspondence of the transition zone was analyzed by means of scanning electron microscope (SEM) observations and energy dispersive spectroscopy (EDS) mapping. Our studies pointed out the formation of a continuous phase between the geopolymer composite and tuff and concrete substrates, highlighting a high compatibility of the geopolymer binder with different kinds of materials. These features indicate a large potential for applications of these materials in Cultural Heritage
Antiplasmodial triterpenoids from the fruits of neem, Azadirachta indica.
J Nat Prod. 2010 Aug 27;73(8):1448-52.
Antiplasmodial triterpenoids from the fruits of neem, Azadirachta indica.
Chianese G, Yerbanga SR, Lucantoni L, Habluetzel A, Basilico N, Taramelli D, Fattorusso E, Taglialatela-Scafati O.
Abstract
Eight known and two new triterpenoid derivatives, neemfruitins A (9) and B (10), have been isolated from the fruits of neem, Azadirachta indica, a traditional antimalarial plant used by Asian and African populations. In vitro antiplasmodial tests evidenced a significant activity of the known gedunin and azadirone and the new neemfruitin A and provided useful information about the structure-antimalarial activity relationships in the limonoid class
Antarctic Special Protected Area 161 as a Reference to Assess the Effects of Anthropogenic and Natural Impacts on Meiobenthic Assemblages
The Antarctic region is usually considered a pristine area. Nevertheless, regional warming
effects and increasing human activities, including the presence of several research stations, are
inducing considerable environmental changes that may affect the ecosystem’s functions. Therefore,
during the XXXIII Antarctic expedition, we carried out an investigation in Terra Nova bay (Ross
Sea), close to the Antarctic Specially Protected Area (ASPA) n.161. In particular, we compared the
effects of two different types of impacts on the meiobenthic assemblages: anthropogenic impact
(AI), associated with the activity of Mario Zucchelli Research Station (MZS), and natural impact
(NI) attributable to a large colony of Adélie penguins (Pygoscelis adeliae) in Adelie Cove. For each
impacted site, a respective control site and two sampling depths (20 and 50 m) were selected. Several
environmental variables (pH, dissolved oxygen, major and minor ions, heavy metals, organic load,
and sediment grain size) were measured and analysed, to allow a comprehensive characterization
of the sampling areas. According to the criteria defined by Unites States Environmental Protection
Agency (US EPA 2009), heavy metal concentrations did not reveal critical conditions. However,
both the MZS (AI20) and penguin colony (NI20) sites showed higher heavy metal concentrations,
the former due to human activities related to the Italian research station, with the latter caused by
the penguins excrements. Meiobenthic richness and abundance values suggested that the worst
ecological condition was consistently related to the Adélie penguins colony. Furthermore, the higher
contribution of r-strategists corroborates the hypothesis that the chronic impact of the penguin
colonies may have stronger effects on the meiobenthos than the human activities at the MZS. Food
is not limited in shallow Antarctic bottoms, and microscale differences in primary and secondary
production processes can likely explain the greater spatial heterogeneity, highlighted both by the
univariate and multivariate attributes of meiobenthic assemblage (i.e., richness, diversity, abundance,
whole structure assemblage, and rare taxa) at the deeper stations. As reported in other geographical
regions, the assemblage structure of rare meiobenthic taxa is confirmed to be more susceptible to
environmental variations, rather than the whole assemblage structure
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