687 research outputs found

    Gravitation and Electromagnetism as Geometrical Objects of a Riemann-Cartan Spacetime Structure

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    In this paper we first show that any coupled system consisting of a gravitational plus a free electromagnetic field can be described geometrically in the sense that both Maxwell equations and Einstein equation having as source term the energy-momentum of the electromagnetic field can be derived from a geometrical Lagrangian proportional to the scalar curvature R of a particular kind of Riemann-Cartan spacetime structure, where those fields are identified as geometrical objects of the structure. We show moreover that the contorsion tensor of the particular Riemann-Cartan spacetime structure of our theory encodes the same information as the one contained in Chern-Simons term that is proportional to the spin density of the electromagnetic field. Next we show that by adding to the geometrical Lagrangian a term describing the interaction of a electromagnetic current with a general electromagnetic plus the gravitational field and a term describing the matter carrier of the current we get Maxwell equations with source term and Einstein equation having as source term the sum of the energy-momentum tensors of the electromagnetic and matter terms. Finally modeling by dust charged matter the carrier of the electromagnetic current we get the Lorentz force equation. Moreover, we prove that our theory is gauge invariant. We also briefly discuss our reasons for the present enterprise.Comment: In this version some few misprints have been corrected and a remark has changed place. Paper will appear in Advances in Applied Clifford Algebra

    Sequence based typing of Legionella pneumophila sg 1 isolated in nosocomial acquired infections in Apulia, Southern Italy

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    Objective. The present report aims to molecularly characterize seven clinical L. pneumophila (L. pn.) sg 1 isolated from noso- comial acquired infections in Apulia region, using the European Working Group on Legionella Infections (EWGLI), sequence- based typing (SBT) and amplified fragment length polymorphism (AFLP) protocols and to compare the identified sequence types (STs) with those available in the EWGLI database. Methods. In the period, January 2000 - December 2012, 151 cases (136 of community and 15 of nosocomial origin) of Legion- naires? disease were notified to the Regional Center for Epide- miology. With regard to nosocomial cases, 8 were confirmed by the isolation of Legionella spp. from respiratory secretions. These clinical isolates were characterized by amplified fragment length polymorphism (AFLP) and sequence-based typing (SBT), using the EWGLI standardized protocol. Results. The clinical isolates belong to ST42, ST23 and ST1. The AFLP confirms the SBT results. Comparing the STs herein detected with those already in the EWGLI SBT database, the 3 STs are frequent in other European countries. Conclusions. The molecular analysis demonstrates that the 3 STs are the most frequent in Italy and in Europe, supporting the hypothesis that some specific L. pn. sg 1 clones have gained widespread dissemination probably due to a common ecological niche. Further researches are required to investigate the potential changing incidence of STs and the fitness of emerging strains or clonal groups in environmental strains

    Pepper mild mottle virus in different water matrices

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    Abstract Background Pepper mild mottle virus (PMMoV), a plant virus belonging to Virgoviridae, has recently been suggested as a potential viral indicator for faecal pollution in aquatic environments, since it has been found to be abundantly excreted from healthy human subjects. Methods The occurrence, amount and diversity of PMMoV was investigated in water environments by nested RT-PCR and TaqMan based quantitative PCR. During 2017-2019, 251 water samples (92 urban wastewaters, 32 treated effluents, 16 surface water samples, 9 estuarine samples, 20 seawater samples, 67 groundwater samples, and 15 drinking waters) were analysed. Results PMMoV was detected in 73/92 (79%) wastewater samples, 22/32 (69%) treated sewages, 11/16 (69%) river samples, 6/9 (67%) estuarine samples, 5/20 (25%) bathing waters, and 9/67 (13%) groundwaters, whilst drinking water samples tested always negative. Mean viral concentrations (genome copies/L) were: raw sewage 4.2 × 106, treated sewage 7.4 × 105, river 3.2 × 103, estuarine waters 9.6 × 102, seawaters 3.0 × 102, groundwaters 7.7 × 101. Conclusions This study highlights the significant occurrence of PMMoV in aquatic environment in Italy, and a clear gradient of viral prevalence and concentrations from polluted to clean waters (wastewaters to drinking waters). Key messages PMMoV is ubiquitous throughout the water cycle in Italy with different concentrations. Studies are needed to evaluate the suitability of PMMoV as a viral indicator for human fecal pollution in waters

    Quantitative Microbial Risk Assessment Applied to Legionella Contamination on Long‐Distance Public Transport

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    The quantitative microbial risk assessment (QMRA) framework is used for assessing health risk coming from pathogens in the environment. In this paper, we used QMRA to evaluate the infection risk of L. pneumophila attributable to sink usage in a toilet cabin on Italian long‐distance public transportation (LDT). LDT has water distribution systems with risk points for Legionella proliferation, as well as premise plumbing for drinking water, but they are not considered for risk assessment. Monitoring data revealed that approximately 55% of water samples (217/398) were positive for L. pneumophila, and the most frequently isolated was L. pneumophila sg1 (64%, 139/217); therefore, such data were fitted to the best probability distribution function to be used as a stochastic variable in the QMRA model. Then, a sink‐specific aerosolization ratio was applied to calculate the inhaled dose, also considering inhalation rate and exposure time, which were used as stochastic parameters based on literature data. At L. pneumophila sg1 concentration ≤100 CFU/L, health risk was approximately 1 infection per 1 million exposures, with an increase of up to 5 infections per 10,000 exposures when the concentrations were ≥10,000 CFU/L. Our QMRA results showed a low Legionella infection risk from faucets on LDT; however, it deserves consideration since LDT can be used by people highly susceptible for the development of a severe form of the disease, owing to their immunological status or other predisposing factors. Further investigations could also evaluate Legionella‐laden aerosols from toilet flushing

    How do Vaccinators Experience the Pandemic? Lifestyle Behaviors in a Sample of Italian Public Health Workers during the COVID-19 Era

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    Public health workers (PHWs) have experienced substantial workload changes because of their role in managing measures to limit the spread of COVID-19. The study’s aim was to assess lifestyle changes in Italian PHWs during the pandemic. PHWs attending an annual meeting completed an anonymous questionnaire assessing their sociodemographic and behavioral characteristics and lifestyle changes during the pandemic. A total of 1000 questionnaires were completed. Most participants (63.5% women, mean age 40 ± 13.1 years) were of normal weight (61.5%), non-smokers (81.9%), had a total screen time of ≥5 h/day (83.1%), and slept at least 6 h/night (88.7%). Approximately one-third consumed sweet foods every day (30%) and did not engage in physical activity (34.6%). Current sweet food consumption, physical activity, and sleep were associated with changes in these behaviors in the last 2 years (Tau-b = 0.155; Tau-b = −0.175; Tau-b = −0.276, respectively, p < 0.001). An increase in remote working was associated with worse sleep (odds ratio (OR) 2.065, 95% confidence interval (CI) 1.482–2.877) and diet (OR 1.982, 95% CI 1.385–2.838), and increased tablet/PC use (OR 3.314, 95% CI 2.358–4.656). Health promotion measures are needed to support the adoption of healthy lifestyles in this population during the current pandemic

    Knowledge and acceptance of COVID-19 vaccination among undergraduate students from central and southern Italy

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    At the end of 2020, the Italian Ministry of Health launched a national vaccination campaign to counteract the COVID-19 pandemic. The present study aimed at appraising levels of knowledge about and acceptance of COVID-19 vaccination in a sample of Italian undergraduates during the first phase of the immunization plan. A web-based questionnaire was administered to students attending universities in Bari, Naples, and Rome during the period February–April 2021. Of the total of 3226 participants, 91.9% were keen to receive a COVID-19 vaccination. More than 80% gave correct answers to questions about COVID-19 vaccine administration, functioning, and effects on community health. However, only 63.8% identified the correct composition of the available vaccines. Knowledge was found to be related to sociodemographic features and COVID-19 vaccination acceptance (p < 0.05). COVID-19 vaccination acceptance was found to be related to having a previous vaccination against influenza (OR 3.806, CI 95% 1.181–12.267; p = 0.025) and knowledge (OR 4.759, CI 95% 2.106– 10.753; p = 0.000). These results show a good level of awareness about COVID-19 vaccination in this population, which may indicate the effectiveness of communication strategies accompanying the COVID-19 immunization campaign in Italy

    Sars‐cov‐2 and public transport in Italy

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    Although direct contact is considered the main mode of transmission of SARS‐CoV‐2, environmental factors play an important role. In this study, we evaluated the presence of SARS‐ CoV‐2 on bus and train surfaces. From the buses, we took samples from the following areas: handrails used to enter or exit the bus, stop request buttons and handles next to the seats. From the trains, the sampled surfaces were handrails used to enter or exit the train, door open/close buttons, handles next to the seats, tables and toilet handles. SARS‐CoV‐2 was detected on 10.7% of the tested surfaces overall, 19.3% of bus surfaces and 2% of train surfaces (p < 0.0001). On the buses, the most contaminated surfaces were the handles near the seats (12.8%), followed by door open/close buttons (12.5%) and handrails (10.5%). Of the five analyzed transport companies, bus companies were the most contaminated, in particular, companies C (40%) and B (23.3%). A greater number of positive samples were found among those taken at 10:00 a.m. and 10:55 a.m. (45% and 40%, respectively). The presence of the virus on many bus surfaces highlights how the sanitation systems on public transport currently in use are not sufficient to limit the spread of SARS‐CoV‐2

    First detection of severe acute respiratory syndrome coronavirus 2 on the surfaces of tourist-recreational facilities in Italy

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    A Coronavirus disease (COVID-19), caused by a new virus called severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), spreads via direct contact through droplets produced by infected individuals. The transmission of this virus can also occur via indirect contact if objects and surfaces are contaminated by secretions from individuals with COVID-19 or asymptomatic carriers. Environmental contamination with SARS-CoV-2 is high in hospital settings; on the contrary, surface contamination in non-healthcare settings is still poorly studied. In this study, the presence of SARS-CoV-2 on the surfaces of 20 tourist-recreational facilities was investigated by performing a total of 100 swabs on surfaces, including refrigerator handles, handrails, counters, tables, and bathroom access doors. Six (6%) swabs from four (20%) tourist-recreational facilities tested positive for SARS-CoV-2; the surfaces that were involved were toilet door handles, refrigerator handles, handrails, and bar counters. This study highlights that SARS-CoV-2 is also present in non-healthcare environments; therefore, in order to limit this worrying pandemic, compliance with behavioral rules and the adoption of preventive and protective measures are of fundamental importance not only in healthcare or work environments but also in life environments

    Safety in wine production. A pilot study on the quality evaluation of prosecco wine in the framework of ue regulation

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    In Italy, wine production is considered a sector of excellence, where the wines’ appreciable sensory features are favored by environmental factors, including weather and climate conditions, which benefit territories with a specific vocation. The whole chain involves many economic and agri-food sector operators, and requires an in-depth assessment of specific risks for identifying critical points, keeping the entire production process under control, and ensuring product traceability. This article describes the results of a pilot study conducted in the Prosecco DOCG (Designations of Controlled and Guaranteed Origin) area, concerning the detection of residues of plant protection products in fifty wine bottles. Although considerably below the maximum residue levels, all the samples tested were positive, ranging from two to five active substances detected in each sample. In addition to the provisions of the European Community legislation, this paper critically evaluates some best practices models that are already used by the Wine Federations of Italy, with the aim of identifying advantages of and areas for improvement in production methods, applicable to raw materials reception, rasping, storage, and bottling phases, in order to guarantee product safety and quality

    Evaluation of air contamination in orthopaedic operating theatres in hospitals in Southern Italy: The IMPACT project

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    Postoperative infections are a concern, especially in total knee and total hip arthroplasty. We evaluated the air quality in orthopaedic operating theatres in southeastern Italy to determine the level of bacterial contamination as a risk factor for postoperative infection. Thirty-five hospitals with operating theatres focused on total knee and total hip arthroplasty participated. We sampled the air passively and actively before surgeries began for the day (at rest) and 15 min after the surgical incision (in operation). We evaluated bacterial counts, particle size, mixed vs turbulent airflow systems, the number of doors, number of door openings during procedures and number of people in the operating theatre. We found no bacterial contamination at rest for all sampling methods, and significantly different contamination levels at rest vs in operation. We found no association between the number of people in the surgical team and bacteria counts for both mixed and turbulent airflow systems, and low bacterial loads, even when doors were always open. Overall, the air quality sampling method and type of ventilation system did not affect air quality
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