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Plants are recognized as sources of aerobically produced methane (CH4), but the seasonality, environmental drivers and significance of CH4 emissions from the canopies of evergreen boreal trees remain poorly understood. We measured the CH4 fluxes from the shoots of Pinus sylvestris (Scots pine) and Picea abies (Norway spruce) saplings in a static, non-steady-state chamber setup to investigate if the shoots of boreal conifers are a source of CH4 during spring. We found that the shoots of Scots pine emitted CH4 and these emissions correlated with the photosynthetically active radiation. For Norway spruce, the evidence for CH4 emissions from the shoots was inconclusive. Our study shows that the canopies of evergreen boreal trees are a potential source of CH4 in the spring and that these emissions are driven by a temperature-by-light interaction effect of solar radiation either directly or indirectly through its effects on tree physiological processes.

Plant shoots can act as sources or sinks of trace gases including methane and nitrous oxide. Accurate measurementsof these trace gas fluxes require enclosing of shoots in closed non-steady state chambers. Due to plant physiological activity, this type of enclosures, however, lead to CO2 depletion in the enclosed air volume, condensation of transpired water, and warmingof the enclosures exposed to sunlight, all of which may bias the flux measurements. Here, we present PlasTraGAS, ab novel measurement system designed for continuous and automated measurements of trace gas and volatile organic compound (VOC) fluxes from plant shoots. The system uses transparent shoot enclosures equipped with Peltier cooling elements and automatically replaces fixated CO2 and removes transpired water from the enclosure. The system is designed for measuring trace gasfluxes over extended periods, capturing diurnal and seasonal variations and linking trace gas exchange to plant physiologicalfunctioning and environmental drivers. Initial measurements show daytime CH4 emissions two pine shoots of 0.056 and 0.089 nmol g−1 foliage d.w.h−1or 7.80 and 13.1 nmol m−2 h−1. Simultaneously measured CO2 uptake rates were 9.2 and 7.6 mmol m−2 sec−1 and transpiration rates of 1.24 and 0.90 mol m−2 h−1. Concurrent measurement of VOC emissionsdemonstrated that potential effects of spectral interferences on CH4 flux measurements were at least ten-fold smaller than themeasured CH4 fluxes. Overall, this new system solves multiple technical problems that so far prevented automated plant shoottrace gas flux measurements, and holds the potential for providing important new insights into the role of plant foliage in the global CH4 and N2O cycles.

This study was aimed at assessing the anti-HBs persistence and immune memory 18–19 y after vaccination against hepatitis B in healthy individuals primed as infants or adolescents. We enrolled 405 teenagers (Group A) vaccinated as infants, and 409 young adults (Group B) vaccinated as adolescents. All vaccinees were tested for anti-HBs and anti-HBc antibodies; those found anti-HBc positive were further tested for HBsAg and HBV DNA. Eight individuals belonging to Group B were positive for anti-HBc alone, and were excluded from analysis. Individuals with anti-HBs concentration ≥ 10 mIU/ml were considered protected while those with anti-HBs concentration

In Italy nucleic acid testing (NAT) became mandatory for hepatitis C virus (HCV) in 2002 and for human immunodeficiency virus (HIV) and hepatitis B virus in 2008. The aim of this study was to monitor the incidence and prevalence of HIV and HCV infections in Italian blood donors and the current residual risk of these infections after the introduction of NAT.The Italian national blood surveillance system includes data from tests used to screen for transfusion-transmissible infections. During the period of this survey (2009-2015), the NAT methods used were the transcription-mediated amplification test, for individual donor testing, and polymerase chain reaction analysis, mainly for pools of six donors. Prevalence and incidence were calculated. Three published formulae were applied to estimate the residual risk (the window period ratio model and the formulae recommended by the European Medicines Agency and the World Health Organization).Overall, 12,258,587 blood donors and 21,808,352 donations were tested for HCV and HIV. The prevalence of HCV decreased from 110.3×10HCV infection has declined over time in both first-time and repeat donors, while the data for HIV infection are stable. All three methods employed in this study showed that the residual risk of transmitting HCV or HIV through an infected blood unit is currently very low in Italy, but there are considerable differences in estimates between methods. Thus, harmonisation of these methods is advisable.

Background Health policy makers often have to face decisions on whether and how to incorporate new vaccines into immunisation plans. This study aims to review and catalogue the relevant current frameworks and taxonomies on vaccines and connect these to the DECIDE Evidence to Decision framework (EtD), a general framework based on evidence-based criteria to guide decision-making on intervention adoption. Methods We systematically searched MEDLINE, EMBASE, Cochrane Library and funding agency websites from 1990 to 2013. We included systematic reviews and primary studies presenting decision-making tools for community vaccine adoption. We qualitatively summarised the reports by purpose, targeted country, principal results, and decisional models. We then extracted and compared the dimensions adopted by vaccine frameworks across studies. Results Fourteen studies (five systematic reviews and nine primary studies) were included. Several factors frequently influenced decision-makers’ views on vaccines: the most frequent political-context factors considered were Importance of illness or problem, Vaccine characteristics, Resource use, and Feasibility. Others such as Values and preferences and Acceptability were less consistently reported. We did not find evidence on the reasons why a framework for vaccine adoption differs from that for decisions on the adoption of an intervention in general, such as the EtD. There are limited data on how dimensions are explained in practical factors and directly linked to coverage decisions. Conclusions This review summarises conceptual models and taxonomy of a heterogeneous and evolving area in health policy decisions. A shared and comprehensive framework on vaccine coverage remains to be achieved with its single dimensions (epidemiologic, effectiveness, economic, and social) valued differently across studies. A generic tool such as the EtD conceptualises all relevant dimensions, and might reduce inconsistencies.

Background Foodborne Hepatitis A Virus (HAV) outbreaks are being recognized as an emerging public health problem in industrialized countries. In 2013 three foodborne HAV outbreaks occurred in Europe and one in USA. During the largest of the three European outbreaks, most cases occurred in Italy (>1,200 cases as of March 31, 2014). A national Task Force was established at the beginning of the outbreak by the Ministry of Health. Mixed frozen berries were early demonstrated to be the source of infection by the identity of viral sequences in patients and in food. In the present study the molecular characterization of HAV isolates from 355 Italian cases is reported. Methods Molecular characterization was carried out by PCR/sequencing (VP1/2A region), comparison with reference strains and phylogenetic analysis. Results A unique strain was responsible for most characterized cases (235/355, 66.1%). Molecular data had a key role in tracing this outbreak, allowing 110 out of the 235 outbreak cases (46.8%) to be recognized in absence of any other link. The data also showed background circulation of further unrelated strains, both autochthonous and travel related, whose sequence comparison highlighted minor outbreaks and small clusters, most of them unrecognized on the basis of epidemiological data. Phylogenetic analysis showed most isolates from travel related cases clustering with reference strains originating from the same geographical area of travel. Conclusions In conclusion, the study documents, in a real outbreak context, the crucial role of molecular analysis in investigating an old but re-emerging pathogen. Improving the molecular knowledge of HAV strains, both autochthonous and circulating in countries from which potentially contaminated foods are imported, will become increasingly important to control outbreaks by supporting trace back activities, aiming to identify the geographical source(s) of contaminated food, as well as public health interventions.

A prospective, 1-year study was performed among Italian first-time, volunteer blood donors, who account for 12% of all donations, in order to assess the frequency and serological patterns of hepatitis B virus infection and the presence of occult infection.Consecutive donors (n=31,190) from 21 blood transfusion centres, from age classes not subjected to universal HBV vaccination, were tested for HBsAg and anti-HBc by commercial immunoassays. Other HBV serological markers were searched for and qualitative and quantitative assessments of HBV-DNA were made in HBsAg and/or anti-HBc-positive individuals.Of the 31,190 donors studied, 100 (0.32%) were positive for both HBsAg and anti-HBc, 2 for HBsAg (0.01%) alone, and 2,593 (8.3%) for anti-HBc. Of these last, 86.7% were also positive for anti-HBs (with or without anti-HBe), 2.9% were positive for anti-HBe without anti-HBs and 10.4% had no other HBV markers (anti-HBc alone). A general north-south increasing gradient of HBV prevalence was observed. Circulating HBV-DNA was found in 96.8% of HBsAg-positive subjects as compared to 0.55% (12/2,186) of anti-HBc-positive/HBsAg-negative subjects, with higher frequencies among anti-HBs-negative than among anti-HBs-positive ones (1.68% vs. 0.37%; p0.01) and among the 57 cases positive for both anti-HBc and anti-HBe (7%). HBV-DNA levels were significantly higher in HBsAg-positive subjects than in HBsAg-negative ones (median: 456 IU/mL vs. 38 IU/mL).The prevalence of HBV infection among Italian first-time blood donors is much lower than in the past. The presence of occult infections in this group was confirmed (frequency: 1 in 2,599), supporting the hypothesis of long-term persistence of HBV infection after clearance of HBsAg. HBsAg and nucleic acid amplification testing for blood screening and vaccination against HBV are crucial in order to further reduce the risk of transfusion-transmitted HBV towards zero.

Dissertação (mestrado) - Pontifícia Universidade Católica de Minas Gerais, Programa de Pós-Graduação em Engenharia Mecânica. Bibliografia: f. 128-134 Resumo: A importância dos sistemas de refrigeração por absorção nos dias de hoje se faz evidente, tendo em vista a crise no setor energético e os apelos ecológicos que vão tomando força diante dos problemas de ordem climática atuais. Este trabalho propõe a utilização de um ciclo refrigeração por absorção aplicado a um veículo automotor para o funcionamento de seu sistema de ar condicionado. A fonte de calor utilizada do sistema foi oriunda do calor rejeitado no sistema de arrefecimento do motor do veículo. A modelagem do sistema foi desenvolvida com o auxílio do software EES (Engineering Equation Solver) e tem como objetivo atender aos requisitos de carga térmica de um automóvel de passeio de pequeno porte. O modelo foi utilizado para simular variações nos diversos componentes e avaliar seu impacto no desempenho do sistema. O projeto englobou a simulação de todos os componentes do sistema observando as limitações da fonte energética disponível. Através de todas as análises, pode-se concluir que a aplicação do sistema de absorção para ar condicionado automotivo é possível, apesar da modelagem apresentada ter obtido como resultado de troca térmica no evaporador equivalente a 4,014 kW, que representa 52,6 % do valor considerado como objetivo, 7,627 kW. Abstract: The importance of absorption applied to refrigeration systems in our times is evident in view of the crisis in the energy sector and environmental demands that will take strength to face ecological and climate problems. This work proposes an absorption cycle applied to an automotive vehicle for operating the air conditioning. The heat source used in the system was the heat rejected in cooling engine system. The modeling system was developed using the software EES (Engineering Equation Solver) and aims to meet the thermal load requirements of a small car. The project includes the design of all components observing the space, energy source and lay out limitations. The model can be used to simulate changes in various components and their impact on the performance of the apparatus. After all the analysis, we could deduce that the application of the absorption cycle to the automotive air conditioning system is viable although the calculations results showed that the heat exchange in the evaporator reached 4,014 kW, that is 52,6 % of the target 7,627 kW.

The overall situation on viral hepatitis prevention and control in Italy was reviewed and evaluated at a Viral Hepatitis Prevention Board (VHPB) meeting in Catania, Sicily, on 7-8 November 2002. Several specific conclusions, drawn from the presentations and discussions, were considered to constitute an example of how to handle these issues in other European and industrialized countries.