299 research outputs found

    Unraveling the Metabolic Potential of Asgardarchaeota in a Sediment from the Mediterranean Hydrocarbon-Contaminated Water Basin Mar Piccolo (Taranto, Italy)

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    Increasing number of metagenome sequencing studies have proposed a central metabolic role of still understudied Archaeal members in natural and artificial ecosystems. However, their role in hydrocarbon cycling, particularly in the anaerobic biodegradation of aliphatic and aromatic hydrocarbons, is still mostly unknown in both marine and terrestrial environments. In this work, we focused our study on the metagenomic characterization of the archaeal community inhabiting the Mar Piccolo (Taranto, Italy, central Mediterranean) sediments heavily contaminated by petroleum hydrocarbons and polychlorinated biphenyls (PCB). Among metagenomic bins reconstructed from Mar Piccolo microbial community, we have identified members of the Asgardarchaeota superphylum that has been recently proposed to play a central role in hydrocarbon cycling in natural ecosystems under anoxic conditions. In particular, we found members affiliated with Thorarchaeota, Heimdallarchaeota, and Lokiarchaeota phyla and analyzed their genomic potential involved in central metabolism and hydrocarbon biodegradation. Metabolic prediction based on metagenomic analysis identified the malonyl-CoA and benzoyl-CoA routes as the pathways involved in aliphatic and aromatic biodegradation in these Asgardarchaeota members. This is the first study to give insight into the archaeal community functionality and connection to hydrocarbon degradation in marine sediment historically contaminated by hydrocarbons

    Optimization of government subsidization strategies for building stock energy refurbishment

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    The high initial investment required in existing building refurbishment can limit the initiative of the building owners and prevent the full exploitation of a huge energy saving potential. Public incentives can play an essential role in fostering the energy retrofitting of the existing buildings and in increasing the renovation rate of the building stock, effectively reducing the energy final uses, the dependence on the fossil fuels, and helping meet the national efficiency targets. Public subsidization are intended to enhance the economic performance in terms of global cost of the energy efficiency measures for the owner, in order to induce positive actions and move optimality from low to high energy efficient solution. In contrast, the overall economic efficiency is obtained with combinations of interventions, able to achieve a certain energy saving target for the entire building stock at the minimum initial Investment Costs (IC). This paper tries to identify the overall economic efficiency in reducing the energy consumption of the existing stock and compares it with the efficiency of solutions optimal from the owner’s perspective, in order to support more efficient subsidization strategies. Different mixes of three reference building archetypes, representative of the existing buildings, are considered to define different possible stocks, in order to analyse their impact on the efficiency of energy renovation solutions. Four groups of energy efficiency measures (EEMs) dealing with respectively the opaque envelope insulation, the windows substitution, the heat generating system replacement, and the mechanical ventilation introduction are defined and their combinations considered

    Internal Versus External Shading Devices Performance in Office Buildings

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    Abstract In this paper different configurations of an open-space office located in Rome has been simulated with EnergyPlus 8 to compare the performance of outdoor and indoor shading devices concerning the thermal and visual comfort and the overall primary energy use. The standard PMV indices [1] have been calculated considering also the effect of the diffuse and beam solar radiation directly reaching the occupants through the windows. Although the use of shades always improves the thermal comfort, the energy demand could increase as an effect of the internal position of shades in combination with particular orientations and glazing types

    Ruptured middle cerebral artery aneurysms. retrospective study and multivariate analysis of 105 patients treated by surgical clipping

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    Objective of the study: We analyze in this study only patients with surgically treated ruptured aneurysms in order to identify statistical significance of each predictive factor in terms of outcome of patients with ruptured MCAAs. Materials and methods: In this retrospective study, we analyzed 105 cases of ruptured MCAAs, admitted from January 2001 to December 2015 at Neurosurgical Department of Umberto I University Hospital of Rome, Italy. Predictive factors evaluated are: Patient’s features (age, sex, co-morbidities), aneurysmal location (proximal, bifurcation or distal) and size of aneurysmal dome (small, large or giant); surgical timing (ultra-early, early, delayed), and Intracerebral Hemorrhage (ICH) volume. For each parameter we calculated mean and standard deviation, covariance and relation coefficient (through the linear regression model). Results: The clinical evaluation of patients assessed through the World Federation of Neurological Surgeons (WFSN) grading scale, that is 5 for 37 patients (35.3%), 4 for 28 patients. In 40% of cases the maximum sac diameter was between 7 mm and 12 mm, while in 67% of the cases the aneurysms concerned the bifurcation of the middle cerebral artery. ICH was associated in 57 cases (54.3%). As far as outcome is concerned, at 3 months, 32 patients (30.47%) had a favourable outcome, while 73 (69.52%) patients had not favourable outcome. To one year, 46 patients (43.8%) had favourable outcomes, while 59 patients (56.19%) had not favourable outcome. The mean outcomes as mean mRS are significantly less favourable in patients with ICH. Conclusion: In MCAAs patients, the presence of ICH strongly affects the outcome with a marked increase in mortality and morbidity. Surgical timing significantly influences the outcomes and ultra-early surgery should always be taken into account

    Comparison of Different Glare Indices through Metrics for Long Term and Zonal Visual Comfort Assessment

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    Nowadays different indices are used for the assessment of the visual discomfort related to glare, such as Daylight Glare Index, Daylight Glare Probability, and Vertical Eye illuminance. Regardless of their effectiveness in detecting glare perception, all these indices are intended to be local and instantaneous, not summarizing the long term glare perception through the space (Carlucci et al. 2015). In this work, a set of metrics able to express both the time constancy, i.e. availability, and the spatial uniformity, i.e. usability, has been used for detecting discrepancies and inconsistencies between the glare indices when dealing with time and space distribution. Results confirm that different glare indices can lead to different conclusions not only when considering point and instantaneous values but also when analysing availability and usability. Moreover, the availability and usability representations, indirectly confirm themselves effective in providing a global assessment of the confined space analysed, even when visual comfort is concerned

    Indoor monitoring and long-term survey to identify the risks of Energy Poverty: the case of social housing in Northern Italy

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    Low-income families often live in poorly heated houses belonging to social housing programs. Tenants’ wellbeing and health in social housing is typically threatened by problems associated with energy inefficiency and poor Indoor Environmental Quality (IEQ). These conditions are among the symptoms of a social issue known as Energy Poverty (EP), which occurs when residents face difficulty in paying energy bills. In 2020 about 2.1 million households (8% of the total) were suffering from energy poverty in Italy. The risk of EP is mainly favored by three factors: the low income of the family, the high final price of energy and the poor technical construction characteristics of the building which can lead to poor IEQ. Four indicators have been proposed by the European Commission and some others developed in the scientific literature, but often neither the thresholds to assess the status of EP nor the methodology to collect data have been defined. This study aims to assess some of the recommended European indicators on a case study. The risks of EP have been investigated in social housing located in Northern Italy by means of an integrated methodology based on a site inspection, a survey, and the continuous monitoring of the indoor environmental parameters during the winter season. The proposed method allowed detecting the presence of EP in 5 dwellings out of 8

    η\eta-Einstein Sasakian immersions in non-compact Sasakian space forms

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    The aim of this paper is to study Sasakian immersions of (non-compact) complete regular Sasakian manifolds into the Heisenberg group and into BN×R \mathbb{B}^N\times \mathbb{R} equipped with their standard Sasakian structures. We obtain a complete classification of such manifolds in the η\eta-Einstein case.Comment: To appear on Annali di Matematica Pura ed Applicata, minor corrections. arXiv admin note: text overlap with arXiv:1810.0077

    On codimension-1 submanifolds of the real and complex projective space

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    Inspired by the analogous result in the algebraic setting (Theorem1) we show (Theorem2) that the product M 7 RP^n of a closed and orientable topological manifold M with the n-dimensional real projective space cannot be embedded into RP^(m+n+1) for all even n > m

    η-Einstein Sasakian immersions in non-compact Sasakian space forms

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    The aim of this paper is to study Sasakian immersions of (non-compact) complete regular Sasakian manifolds into the Heisenberg group and into BN× R equipped with their standard Sasakian structures. We obtain a complete classification of such manifolds in the η-Einstein case
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