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A transient model for devolatilization of a dry or wet cylindrical wood log is developed. The model is mesh-based and 1D even though the extension to 2D or 3D can easily be done. The stiff solid matrix of porous wood contains the gas phase (non-condensable gases, condensable gases and air). The gas is assumed to be ideal and Darcy's law is applied to define the gas phase motion within the pores. Devolatilization is described with a primary three independent competitive reactions model which is followed by secondary tar cracking and re-polymerization reactions. Overall good agreement between measurements and modeling results was found. This model can accurately predict the solid mass loss behavior, temperature history at the surface and in the wood log center. The model was applied to predict the pressure in the wood log center with respect to time. Special focus is on the identification of parameters that influence the pressure peak formation in the center of the wood log., Proceedings of the 25th European Biomass Conference and Exhibition, 12-15 June 2017, Stockholm, Sweden, pp. 561-565

MnTBAP is often referred to as an SOD mimic in numerous models of oxidative stress. We have recently reported that pure MnTBAP does not dismute superoxide, but commercial or poorly purified samples are able to perform O 2 ·− dismutation with low-to-moderate efficacy via non-innocent Mn-containing impurities. Herein, we show that neither commercial nor pure MnTBAP could substitute for SOD enzyme in a SOD-deficient Escherichia coli model, whereas MnTE-2-PyP-treated SOD-deficient E. coli grew as well as a wild-type strain. This SOD-specific system indicates that MnTBAP does not act as an SOD mimic in vivo. In another model, carrageenan-induced pleurisy in mice, inflammation was evidenced by increased pleural fluid exudate and neutrophil infiltration and activation: these events were blocked by 0.3 mg/kg MnTE-2-PyP and, to a slightly lesser extent, by 10 mg/kg of either MnTBAP. Also, 3-nitrotyrosine formation, an indication of peroxynitrite existence in vivo, was blocked by both compounds; again MnTE-2-PyP was 33-fold more effective. Pleurisy model data indicate that MnTBAP exerts some protective actions in common with MnTE-2-PyP, which are not O 2 ·− related and can be fully rationalized if one considers that the common biological role shared by MnTBAP and MnTE-2-PyP is related to their reduction of peroxynitrite and carbonate radical, the latter arising from ONOOCO 2 adduct. The log k cat (O 2 ·− ) value for MnTBAP is estimated to be about 3.16, which is ~ 5 and ~ 6 orders of magnitude smaller than the SOD activities of the potent SOD mimic MnTE-2-PyP and Cu,Zn-SOD, respectively. This very low value indicates that MnTBAP is too inefficient at dismuting superoxide to be of any biological impact, which was confirmed in the SOD-deficient E. coli model. The peroxynitrite scavenging ability of MnTBAP, however, is only ~ 2.5 orders of magnitude smaller than that of MnTE-2-PyP and is not significantly affected by the presence of the SOD-active impurities in the commercial MnTBAP sample (log k red (ONOO − ) = 5.06 for pure and 4.97 for commercial sample). The reduction of carbonate radical is equally fast with MnTBAP and MnTE-2-PyP. The dose of MnTBAP required to yield oxidative stress protection and block nitrotyrosine formation in the pleurisy model is > 1.5 orders of magnitude higher than that of MnTE-2-PyP, which could be related to the lower ability of MnTBAP to scavenge peroxynitrite. The slightly better protection observed with the commercial MnTBAP sample (relative to the pure MnTBAP) could arise from its impurities, which, by scavenging O 2 ·− , reduce consequently the overall peroxynitrite and secondary ROS/RNS levels. These observations have profound biological repercussions as they may suggest that the effect of MnTBAP observed in numerous studies may conceivably relate to peroxynitrite scavenging. Moreover, provided that pure MnTBAP is unable to dismute superoxide at any significant extent, but is able to partially scavenge peroxynitrite and carbonate radical, this compound may prove valuable in distinguishing ONOO − /CO 3 ·− from O 2 ·− pathways.

The Dodecanese region has a high prevalence of marine alien species due to its close proximity to the Suez Canal and associated Suez shipping lanes, as well as its location at biogeographical border between sub-tropical and tropical biota. This region is therefore very important for the early detection of alien species entering the Mediterranean Sea via the Suez Canal and it is imperative that monitoring of alien species is continued in order to assess the levels of biological invasion. We present results of marine alien surveys, carried out in April 2014 on the island of Rodos. Surveys were performed by a team of marine taxonomic experts and students as part of an EU wide training school, coordinated by the COST Action TD1209 “Alien Challenge”. A variety of survey methods were employed to cover a number of coastal habitats. These included: rapid assessment surveys of epibiota on artificial structures in harbours, rapid assessment snorkelling surveys of biota on sublittoral bedrock, and quantified fishing surveys (both boat-seine and trammel net fishing methods). A total of 33 alien and cryptogenic species were recorded across all the survey techniques. Of these species, 9 represented first records for Rodos: the foraminiferan Amphisorus hemprichii, the polychaetes Branchiomma bairdi, Dorvillea similis, Hydroides dirampha and Pseudonereis anomala, the molluscs Aplysia parvula, Chama pacifica and Septifer cumingii, and the bryozoan Hippopodina feegeensis. Of note the record of the Lessepsian invader Dorvillea similis represents the second record in the Mediterranean Sea. Alien fish species represented a small but notable proportion of the diversity, biomass and number of individuals in fishing catch of both fishing methods. All alien fish species observed were already known to be present in Rodos. The addition of species firstly recorded in this study brings the total number of marine alien and cryptogenic species in the Dodecanese region up to 129 species. The vast majority of these alien species have entered unaided via the Suez Canal, but an increasing number have been introduced through hull fouling or ballast water transfer from shipping. The results highlight the value of conducting marine alien surveys with teams of a diverse range of taxonomic expertise, both in its scientific output and student training. © 2015 The Author(s) and 2015 REABIC.

Acrylamide (AA) is a well-known industrial chemical classified as a probable human carcinogen. Benign and malignant tumours at different sites, including the mammary gland, have been reported in rodents exposed to AA. This xenobiotic is also formed in many carbohydrate-rich foods prepared at high temperatures. For this reason, AA is an issue of concern in terms of human cancer risk. The epoxide glycidamide (GA) is thought to be the ultimate genotoxic AA metabolite. Despite extensive experimental and epidemiological data focused on AA-induced breast cancer, there is still lack of information on the deleterious effects induced by GA in mammary cells. The work reported here addresses the characterisation and modulation of cytotoxicity, generation of reactive oxygen species, formation of micronuclei (MN) and quantification of specific GA-DNA adducts in human MCF10A epithelial cells exposed to GA. The results show that GA significantly induces MN, impairs cell proliferation kinetics and decreases cell viability at high concentrations by mechanisms not involving oxidative stress. KU55933, an inhibitor of ataxia telangiectasia mutated kinase, enhanced the cytotoxicity of GA (P < 0.05), supporting a role of this enzyme in regulating the repair of GA-induced DNA lesions. Moreover, even at low GA levels, N7-GA-Gua adducts were generated in a linear dose-response manner in MCF10A cells. These results confirm that human mammary cells are susceptible to GA toxicity and reinforce the need for additional studies to clarify the potential correlation between dietary AA exposure and breast cancer risk in human populations.