657 research outputs found
Improving Knowledge of Risk in Dangerous Goods Transport
In order to increase safety as far as dangerous goods transport is concerned, the DESTINATION project has been developed since 2010 in the framework of the Italy/Switzerland Operational Program for Transfrontier Co-operation 2007-2013. The project was born to satisfy the increasing needs of public bodies to share data on hazardous material land transportation and to develop instruments and methodologies to ensure territorial and environmental protection. The project aims to reach this purpose through the increased knowledge of the vulnerable subjects, people and environment, and of the transport activity itself, by using and defining an architecture of data acquisition based on “On Ground Units” (OGU) and “On Board Units” (OBU). These data will be used as an input for a new information system called GIIS (Global Integrated Information System), which manages a risk analysis model of the land transportation of hazardous materials to assess human and environmental vulnerabilities. The GIIS will provide a more effective management of land planning by providing authorities with the possibility of implementing a rational restriction to vehicles transporting dangerous goods within specific areas
Arbuscular mycorrhizal fungi as a tool to ameliorate the phytoremediation potential of poplar: biochemical and molecular aspects
Poplar is a suitable species for phytoremediation, able to tolerate high concentrations of heavy metals (HMs). Arbuscular mycorrhizal fungi (AMF) form symbiotic associations with the roots of most land plants; they improve nutrient uptake and enhance phytoextraction of HMs while alleviating stress in the host plant. This review summarizes previous results from field and greenhouse studies conducted by us and dealing with this topic. In a field trial on a highly Zn- and Cu-contaminated site, differences in plant survival and growth were observed among 168 clones originating from natural populations of Populus alba L. and Populus nigra L. from northern Italy. After two and a half years from planting, the density, activity and metabolic versatility of the culturable fraction of the soil bacteria in the HM-polluted field was higher in the soil close to where larger poplar plants were growing, in spite of comparable HM concentrations recorded in these soils. One well-performing clone of P. alba (AL35), which accumulated a higher concentration of both metals and had high foliar polyamine (PA) levels, was used for further investigation. In a greenhouse study, AL35 cuttings pre-inoculated with AMF (Glomus mosseae or Glomus intraradices) and then transferred to pots containing soil, collected from the HM-polluted site, displayed growth comparable to that of controls grown on unpolluted soil, in spite of higher Cu and Zn accumulation. Such plants also showed an overall up-regulation of metallothionein (MT) and PA biosynthetic genes, together with increased PA levels. A genome-wide transcriptomic (cDNA-AFLP) analysis allowed the identification of a number of genes, mostly belonging to stress-related functional categories of defense and secondary metabolism, that were differentially regulated in mycorrhizal vs. non mycorrhizal plants. A proteomic analysis revealed that, depending on sampling time, changes in protein profiles were differentially affected by AMF and/or HMs. It is concluded that soil-borne microorganisms affect plant performance on HM-polluted soil. In particular, mycorrhizal plants exhibited increased capacity for phytostabilization of HMs, together with improved growth. Their greater stress tolerance may derive from the protective role of PAs, and from the strong modulation in the expression profiles of stress-related genes and proteins
Corrected overlap weight and clustering coefficient
We discuss two well known network measures: the overlap weight of an edge and
the clustering coefficient of a node. For both of them it turns out that they
are not very useful for data analytic task to identify important elements
(nodes or links) of a given network. The reason for this is that they attain
their largest values on maximal subgraphs of relatively small size that are
more probable to appear in a network than that of larger size. We show how the
definitions of these measures can be corrected in such a way that they give the
expected results. We illustrate the proposed corrected measures by applying
them on the US Airports network using the program Pajek.Comment: The paper is a detailed and extended version of the talk presented at
the CMStatistics (ERCIM) 2015 Conferenc
Impact of Phosphatic Nutrition on Growth Parameters and Artemisinin Production in Artemisia annua Plants Inoculated or Not with Funneliformis mosseae
Artemisia annua L. is a medicinal plant appreciated for the production of artemisinin, a molecule used for malaria treatment. However, the natural concentration of artemisinin in planta is low. Plant nutrition, in particular phosphorus, and arbuscular mycorrhizal (AM) fungi can affect both plant biomass and secondary metabolite production. In this work, A. annua plants were inoculated or not with the AM fungus Funneliformis mosseae BEG12 and cultivated for 2 months in controlled conditions at three different phosphatic (P) concentrations (32, 96, and 288 µM). Plant growth parameters, leaf photosynthetic pigment concentrations, artemisinin production, and mineral uptake were evaluated. The different P levels significantly affected the plant shoot growth, AM fungal colonization, and mineral acquisition. High P levels negatively influenced mycorrhizal colonization. The artemisinin concentration was inversely correlated to the P level in the substrate. The fungus mainly affected root growth and nutrient uptake and significantly lowered leaf artemisinin concentration. In conclusion, P nutrition can influence plant biomass production and the lowest phosphate level led to the highest artemisinin concentration, irrespective of the plant mineral uptake. Plant responses to AM fungi can be modulated by cost–benefit ratios of the mutualistic exchange between the partners and soil nutrient availability
Phosphatic nutrition affects biomass production, photosynthetic pigment concentration and artemisinin biosynthesis in A. annua plants grown in presence or not of F. mosseae
Increasing Feeder PV Hosting Capacity by Regulating Secondary Circuit Voltages
Voltage rise is one of the major concerns that limits the photovoltaic (PV) hosting capacity or the maximum amount of PV generation that a distribution circuit can accommodate. This paper examines the effectiveness of low-voltage distribution static compensators (LV-DSTATCOMs) in increasing the PV hosting capacity of distribution circuits by mitigating voltage rise. Stochastic analysis framework is used to determine the PV hosting capacity while an iterative placement technique is used to identify effective device locations. To provide insights on the optimal device size, number, and control settings, sensitivity analysis is carried out. The results show that, with appropriate size and control settings, installation of few LV-DSTATCOMs in a distribution circuit can significantly increase its PV hosting capacity. For the circuit under consideration, a set of 23 devices has increased the PV hosting capacity from 15% to 100% of the median day time peak load
Metaproteomic characterization of the Vitis vinifera rhizosphere
The rhizosphere is a hotspot of microbial activity where the release of root exudates stimulates bacterial density and diversity. The majority of the bacterial cells in soil are viable, unculturable, but active. Proteomic tools could be useful in gaining information about microbial community activity and to better understand the real interactions between roots and soil. The aim of this work was to characterize the bacterial community associated with Vitis vinifera cv. Pinot Noir roots using a metaproteome approach. Our results confirmed the large potential of proteomics in describing the environmental microbial communities and their activities: in particular, we showed that bacteria belonging to Streptomyces, Bacillus, Bradyrhizobium, Burkholderia and Pseudomonas genera are the most active in protein expression. Concerning the biological activity of these genera in the rhizosphere, we observed the exclusive presence of the phosphorus metabolic process and the regulation of primary metabolic processes. To our knowledge, this is the first study reporting the rhizosphere proteome of V. vinifera, describing the bacterial community structure and activity of an important ecosystem for the Italian landscape, agriculture and economy
Climatic zone and soil properties determine the biodiversity of the soil bacterial communities associated to native plants from desert areas of north-central algeria
Algeria is the largest country in Africa characterized by semi-arid and arid sites, located in the North, and hypersaline zones in the center and South of the country. Several autochthonous plants are well known as medicinal plants, having in common tolerance to aridity, drought and salinity. In their natural environment, they live with a great amount of microbial species that altogether are indicated as plant microbiota, while the plants are now viewed as a \u201cholobiont\u201d. In this work, the microbiota of the soil associated to the roots of fourteen economically relevant autochthonous plants from Algeria have been characterized by an innovative metagenomic approach with a dual purpose: (i) to deepen the knowledge of the arid and semi-arid environment and (ii) to characterize the composition of bacterial communities associated with indigenous plants with a strong economic/commercial interest, in order to make possible the improvement of their cultivation. The results presented in this work highlighted specific signatures which are mainly determined by climatic zone and soil properties more than by the plant species
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