329 research outputs found

    Assessment of Failure Frequencies of Pipelines in Natech Events Triggered by Earthquakes

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    During a seismic event, underground pipelines can undergo to significant damages with severe implications in terms of life safety and economic impact. This type of scenarios falls under the definition of Natech. In recent years, quantitative risk analysis became a pivotal tool to assess and manage Natech risk. Among the tools required to perform the quantitative assessment of Natech risk, vulnerability models are required to characterize equipment damages from natural events. This contribution is focused on the review of the pipeline vulnerability models available for the case of earthquakes. Two main categories of models have been identified in the literature. A first category proposes the repair rate as performance indicator for the damage of pipeline due to seismic load, and gives as output the number of required repairs per unit length. A second category proposes fragility curves associated with risk states depending on the mechanism of ground failure. In the framework of Natech risk assessment, the latter have the important advantage of having clearly and unambiguously defined the risk status (and thus the extent of the release) with which they are associated. A subset of vulnerability models deemed more appropriate to be applied in the framework of Natech risk assessment is then identified. Their application to the assessment of the expected frequencies of release events due to pipeline damage is provided, enabling their comparison and the discussion of the relative strengths and weaknesses

    Chicory and Jerusalem artichoke productivity in different areas of Italy, in relation to water availability and time of harvest

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    Inulin is an important polysaccharide synthesised by different crops, which, in the EU has been included in the system of sugar quotas since 1994. Currently, one of the major problems of the agro-industry is the need to extend the length of the sugar crop harvest season. It was therefore decided, also in relation to the increased demand for inulin, to study the two main inulin producing crops in Italy (chicory and Jerusalem artichoke), to verify yield and quality potential and stability in relation to some important agronomic factors such as irrigation and time of harvest. The work was conducted in 1999 and 2000 in four areas of Italy (Udine, Rovigo, Bologna and Bari). The effects evaluated were time of harvest (3 for chicory and 2 for Jerusalem artichoke) and irrigation system (evapotranspiration replacement and dry regime, with irrigation applied only when strictly necessary) on the production of storage organs, sugars and inulin in the two crops. The highest chicory root yield was in Bologna, with an average production of 65.6 t ha -1 (fresh weight), compared to Rovigo (54.4 t ha -1 ), Bari (46.5 t ha -1 ) and Udine (38.7 t ha -1). For final tuber yield in Jerusalem artichoke, Bari was the most productive environment with an average of 80 t ha -1 , followed by Bologna (61 t ha -1 ) and Udine (55.5 t ha -1 ). However, when this crop is whole-plant harvested (stalks and tubers) at pre-flowering, Bologna, with high stalk yields (58.7 t ha -1) appeared to be the most suitable environment. This type of harvesting was also shown to be more productive in terms of sugar and inulin yield. The total sugar content in the different organs analysed (roots, stalk and tubers) was always higher in Udine compared to Bologna, for both crops. Lastly, the length of the inulin chain (average degree of polymerisation [DP]) diminishes with the delaying of the harvest in both crops. The Bologna area had the highest potential in terms of chicory root production, while for the tubers yield of Jerusalem artichoke, the Bari environment was the most productive. But, when Jerusalem artichoke is instead considered as a crop for whole-plant harvest (stalks and tubers), Bologna, with a very high stalk yields, becomes the most suitable area. The highest sugar content in roots, stalks and tubers of both crops was found in the Udine tria

    Genotype × Environment Interactions of Industrial Hemp Cultivars Highlight Diverse Responses to Environmental Factors

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    Starting with the 2014 Farm Bill, hemp (Cannabis sativa L.) is being re-introduced as an industrial crop in the United States. Since the crop has been absent for over 70 yr, little is known regarding the genetic mechanisms controlling economically relevant traits. Particularly, with federal legality of the crop hinging on a stringent tetrahydrocannabinol (THC) content of 0.3% or less, it is necessary to assess variance in this trait due to environmental effects and genotype × environment interactions (GEI) to avoid running afoul of federal law. Understanding how physical and biochemical traits respond to the environment also plays a strong role in selecting and developing appropriate cultivars for production in diverse growing regions. In 2016 we performed cultivar trials in multiple environments in Colorado to assess performance characteristics of a diverse set of germplasm from breeding programs across Europe and Asia. From these data, we were able to identify traits nearly entirely controlled by genetic factors, like days to maturity and THC and cannabidiol (CBD) production. We also identified traits strongly influenced by the environment and GEI, like grain yield, plant height, and water use. Individual cultivars also exhibited widely varying degrees of sensitivity to the environment. This underscores the importance of continued work to characterize genetic control of hemp traits to expedite breeding of cultivars that are well-adapted to target growing region

    New technologies for radioactive waste monitoring: Results and perspectives from recent experience

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    With the initial support of the INFN-Energy committee throughout the last ten years a few activities have been pursued aimed at the improvement of radioactive waste management. Nowadays new technologies make possible the development of low-cost systems capable of monitoring the radioactivity coming out of (spent) nuclear fuel casks or radwaste drums. Simple, compact and effective radiation counters were developed at INFN for the detection of gamma rays and neutrons, suitable to be deployed as a distributed network for the real time monitoring of radioactive waste from the very low up to the highest level, and possibly preluding to a mass deployment benefitting both safety and security. Indeed, in such a framework any change in counting rates, or even a sensor blackout, could be interpreted as a possible safety or security breach. Techniques for sorting and segregating the radioactive waste have also been studied and a dedicated prototype for the gamma/visible imaging with spectroscopic features is currently being developed. On top of the new interesting technical features accessible by means of distributed networks of devices, one should also focus on the psychological impact they could have on the general public acceptability of a finely monitored repository. Tests performed on radioactive waste of all categories, including spent fuel, showed quite promising results

    Thermal neutron conversion by high purity 10B-enriched layers: PLD-growth, thickness-dependence and neutron-detection performances

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    Neutron applications and detection are of paramount importance in industry, medicine, scientific research, homeland security, production of extreme UV optics and so on. Neutron detection requires a converter element that, as a result of its interaction with neutrons, produces reaction products (mainly charged particles) whose detection can be correlated with the neutron flux. Reduced availability and increased cost of the most used converter element, 3He, have triggered research efforts for alternative materials, proper deposition methods and new detector architectures. 10B converter is a valid alternative to 3He thanks to its high thermal neutron cross section and relatively high Q value. In this paper we report on the room temperature Pulsed Laser Deposition (PLD) of high quality and uniform 10B films with the expected density, different thickness values (0.5, 1.0, 1.2, 1.5 and 2.0 μm) and uniform thickness over a circular area of about 30 mm in diameter. Additionally, they are adherent to the substrate with a negligible presence of contaminants. The conversion properties of such 10B coatings coupled to a Si solid state detector are studied upon exposure to a neutron flux from an Am-Be neutron source (2.2·106 n/s). The experimental results, compared with spectra simulated by using a GEANT4 code, present a good agreement and efficiencies of the order of a few percent

    Highly predictive genetic markers distinguish drug-type from fiber-type cannabis sativa L

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    Genetic markers can be used in seeds and in plants to distinguish drug-type from fiber-type Cannabis Sativa L. varieties even at early stages, including pre-germination when cannabinoids are not accumulated yet. With this aim, this paper reports sequencing results for tetrahydrocannabinolic acid synthase (THCAS) and cannabidiolic acid synthase (CBDAS) genes from 21 C. sativa L. varieties. Taking into account that THCAS- and CBDAS-derived enzymes compete for the same substrate, the novelty of this work relies in the identification of markers based on bothTHCASandCBDASrather than THCAS alone. Notably, in our panel, we achieved an adequate degree of discrimination (AUC 100%) between drug-type and fiber-type cannabis samples. Our sequencing approach allowed identifying multiple genetic markers (single-nucleotide polymorphisms\u2014SNPs\u2014and a deletion/insertion) that effectively discriminate between the two subgroups of cannabis, namely fiber type vs. drug type. We identified four functional SNPs that are likely to induce decreased THCAS activity in the fiber-type cannabis plants. We also report the finding on a deletion in the CBDAS gene sequence that produces a truncated protein, possibly resulting in loss of function of the enzyme in the drug-type varieties. Chemical analyses for the actual concentration of cannabinoids confirmed the identification of drug-type rather than fiber-type genotypes. Genetic markers permit an early identification process for forensic applications while simplifying the procedures related to detection of therapeutic or industrial hemp

    Metformin plus chemotherapy versus chemotherapy alone in the first-line treatment of HER2-negative metastatic breast cancer. The MYME randomized, phase 2 clinical trial

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    Purpose: To investigate the efficacy of metformin (M) plus chemotherapy versus chemotherapy alone in metastatic breast cancer (MBC). Methods: Non-diabetic women with HER2-negative MBC were randomized to receive non-pegylated liposomal doxorubicin (NPLD) 60 mg/m2 + cyclophosphamide (C) 600 mg/m2 × 8 cycles Q21 days plus M 2000 mg/day (arm A) versus NPLD/C (arm B). The primary endpoint was progression-free survival (PFS). Results: One-hundred-twenty-two patients were evaluable for PFS. At a median follow-up of 39.6 months (interquartile range [IQR] 24.6-50.7 months), 112 PFS events and 71 deaths have been registered. Median PFS was 9.4 months (95% CI 7.8-10.4) in arm A and 9.9 (95% CI 7.4-11.5) in arm B (P = 0.651). In patients with HOMA index < 2.5, median PFS was 10.4 months (95% CI 9.6-11.7) versus 8.5 (95% CI 5.8-9.7) in those with HOMA index ≥ 2.5 (P = 0.034). Grade 3/4 neutropenia was the most common toxicity, occurring in 54.4% of arm A patients and 72.3% of the arm B group (P = 0.019). M induced diarrhea (G2) was observed in 8.8% of patients in Arm A. The effect of M was similar in patients with HOMA index < 2.5 and ≥ 2.5, for PFS and OS. Conclusions: The MYME trial failed to provide evidence in support of an anticancer activity of M in combination with first line CT in MBC. A significantly shorter PFS was observed in insulin-resistant patients (HOMA ≥ 2.5). Noteworthy, M had a significant effect on CT induced severe neutropenia. Further development of M in combination with CT in the setting of MBC is not warranted
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