ICONE18-29098 TESTING OF TRANSURANUS CODE FOR RIA ANALYSIS: THE FK-1 NSRR CASE

ABSTRACT -Reactivity Initiated Accident (RIA) leads to an unwanted increase in fission rate and power in a region In the FK-1 test, a STEP I BWR rodlet, previously irradiated in the Fukushima Daiichi Nuclear Power Station (Unit 3) operated by the Tokyo Electric Power COmpany (TEPCO) up to 45 MWd/kg HM , was subjected to a peak enthalpy insertion of 544 J/g. In this paper the code findings for the FK-1 test are discussed on the basis of the experimental data and the predictions of other stand-alone codes for transient analysis. The FK-1 predictions of FRAPTRAN (2001) , FALCON (2003) an

A combined fragment-based virtual screening and STD-NMR approach for the identification of E-cadherin ligands

Cadherins promote cell-cell adhesion by forming homophilic interactions via their N-terminal extracellular domains. Hence, they have broad-ranging physiological effects on tissue organization and homeostasis. When dysregulated, cadherins contribute to different aspects of cancer progression and metastasis; therefore, targeting the cadherin adhesive interface with small-molecule antagonists is expected to have potential therapeutic and diagnostic value. Here, we used molecular docking simulations to evaluate the propensity of three different libraries of commercially available drug-like fragments (nearly 18,000 compounds) to accommodate into the Trp2 binding pocket of E-cadherin, a crucial site for the orchestration of the protein's dimerization mechanism. Top-ranked fragments featuring five different aromatic chemotypes were expanded by means of a similarity search on the PubChem database (Tanimoto index >90%). Of this set, seven fragments containing an aromatic scaffold linked to an aliphatic chain bearing at least one amine group were finally selected for further analysis. Ligand-based NMR data (Saturation Transfer Difference, STD) and molecular dynamics simulations suggest that these fragments can bind E-cadherin mostly through their aromatic moiety, while their aliphatic portions may also diversely engage with the mobile regions of the binding site. A tetrahydro-β-carboline scaffold functionalized with an ethylamine emerged as the most promising fragment

Plutonia-Thoria Fuel Cycle as Starting Solution for a wider Thorium Use

This paper is focused on a description of thoria fuel option. Our opinion is that this option, beyond being a valuable way to exploit the energy content of plutonium without further breeding it, may be a starting point for introducing an Uranium-Thorium fuel cycle, based on a different strategic context with respect to past proposals. The option is based on the adoption of current or advanced PWRs, the latter characterised by a reduced fuel power density, always adopting conventional fuel rods and assemblies. A three-batches full core loading scheme is assumed. The thoria-plutonia composition is determined by the constraints to obtain at Beginning Of Life (BOL) a non positive void coefficient, and to reach a burnup as high as possible. Different fuel compositions and pellet radius are considered. The plutonium content is in the range of 4.5÷15%, mainly depending on the plutonium quality, namely Weapon Grade (WG) or Reactor Grade (RG). The results are in terms of dynamic coefficients, life duration, plutonium consumption and final isotopic compositions. These fuels show the capability to destroy about 40÷60% of total plutonium for RG, while this figure rises to 65÷70% for WG. These values are well above those obtained by MOX option. A variant to eliminate any proliferation concern foresees the addition of small quantities of 238U at the expenses of a reduction of the fuel burnup and its capacity in burning RG plutonium, while the opposite occurs for WG. The low boron worth is not different from the MOX one, being related mainly to the plutonium content, and much less to the chosen fertile isotope. Therefore, modifications of control devices for a full core strategy is not expected to be different in the two cases. The results confirm the viability of this proposal, apt to future variants, including those connected to accelerator actinide burning solution. An irradiation experiment, expe-cted to take place at Halden HWBR in the context of the ENEA participation to the Halden Project, is the main part of the Inert Matrix – Thoria fuel R&D activity presently underway as a Polytechnic of Milan–ENEA co-operation

Exploring E-cadherin-peptidomimetics interaction using NMR and computational studies

Cadherins are homophilic cell-cell adhesion molecules whose aberrant expression has often been shown to correlate with different stages of tumor progression. In this work, we investigate the interaction of two peptidomimetic ligands with the extracellular portion of human E-cadherin using a combination of NMR and computational techniques. Both ligands have been previously developed as mimics of the tetrapeptide sequence Asp1-Trp2-Val3-Ile4 of the cadherin adhesion arm, and have been shown to inhibit E-cadherin-mediated adhesion in epithelial ovarian cancer cells with millimolar potency. To sample a set of possible interactions of these ligands with the E-cadherin extracellular portion, STD-NMR experiments in the presence of two slightly different constructs, the wild type E-cadherin-EC1-EC2 fragment and the truncated E-cadherin-(Val3)-EC1-EC2 fragment, were carried out at three temperatures. Depending on the protein construct, a different binding epitope of the ligand and also a different temperature effect on STD signals were observed, both suggesting an involvement of the Asp1-Trp2 protein sequence among all the possible binding events. To interpret the experimental results at the atomic level and to probe the role of the cadherin adhesion arm in the dynamic interaction with the peptidomimetic ligand, a computational protocol based on docking calculations and molecular dynamics simulations was applied. In agreement with NMR data, the simulations at different temperatures unveil high variability/dynamism in ligand-cadherin binding, thus explaining the differences in ligand binding epitopes. In particular, the modulation of the signals seems to be dependent on the protein flexibility, especially at the level of the adhesive arm, which appears to participate in the interaction with the ligand. Overall, these results will help the design of novel cadherin inhibitors that might prevent the swap dimer formation by targeting both the Trp2 binding pocket and the adhesive arm residues. Author summary Classical cadherins are the main adhesive proteins at the intercellular junctions and play an essential role in tissue morphogenesis and homeostasis. A large number of studies have shown that cadherin aberrant expression and/or dysregulation often correlate with pathological processes, such as tumor development and progression. Notwithstanding the emerging role played by cadherins in a number of solid tumors, the rational design of small inhibitors targeting these proteins is still in its infancy, likely due to the challenges posed by the development of small drug-like molecules that modulate protein-protein interactions and to the structural complexity of the various cadherin dimerization interfaces that constantly form and disappear as the protein moves along its highly dynamic and reversible homo-dimerization trajectory. In this work, we study the interaction of two small molecules with the extracellular portion of human E-cadherin using a combination of spectroscopic and computational techniques. The availability of molecules interfering in the cadherin homophilic interactions could provide a useful tool for the investigation of cadherin function in tumors, and potentially pave the way to the development of novel alternative diagnostic and therapeutic interventions in cadherin-expressing solid tumors

Distribution and diversity of Phytophthora across Australia

The introduction and subsequent impact of Phytophthora cinnamomi within native vegetation is one of the major conservation issues for biodiversity in Australia. Recently, many new Phytophthora species have been described from Australia's native ecosystems; however, their distribution, origin, and potential impact remain unknown. Historical bias in Phytophthora detection has been towards sites showing symptoms of disease, and traditional isolation methods show variable effectiveness of detecting different Phytophthora species. However, we now have at our disposal new techniques based on the sampling of environmental DNA and metabarcoding through the use of high-throughput sequencing. Here, we report on the diversity and distribution of Phytophthora in Australia using metabarcoding of 640 soil samples and we compare the diversity detected using this technique with that available in curated databases. Phytophthora was detected in 65% of sites, and phylogenetic analysis revealed 68 distinct Phytophthora phylotypes. Of these, 21 were identified as potentially unique taxa and 25 were new detections in natural areas and/or new introductions to Australia. There are 66Phytophthora taxa listed in Australian databases, 43 of which were also detected in this metabarcoding study. This study revealed high Phytophthora richness within native vegetation and the additional records provide a valuable baseline resource for future studies. Many of the Phytophthora species now uncovered in Australia's native ecosystems are newly described and until more is known we need to be cautious with regard to the spread and conservation management of these new species in Australia's unique ecosystems

Transferability of PCR-based diagnostic protocols: An international collaborative case study assessing protocols targeting the quarantine pine pathogen Fusarium circinatum

[EN] Fusarium circinatum is a harmful pathogenic fungus mostly attacking Pinus species and also Pseudotsuga menziesii, causing cankers in trees of all ages, damping-off in seedlings, and mortality in cuttings and mother plants for clonal production. This fungus is listed as a quarantine pest in several parts of the world and the trade of potentially contaminated pine material such as cuttings, seedlings or seeds is restricted in order to prevent its spread to disease-free areas. Inspection of plant material often relies on DNA testing and several conventional or real-time PCR based tests targeting F. circinatum are available in the literature. In this work, an international collaborative study joined 23 partners to assess the transferability and the performance of nine molecular protocols, using a wide panel of DNA from 71 representative strains of F. circinatum and related Fusarium species. Diagnostic sensitivity, specificity and accuracy of the nine protocols all reached values >80%, and the diagnostic specificity was the only parameter differing significantly between protocols. The rates of false positives and of false negatives were computed and only the false positive rates differed significantly, ranging from 3.0% to 17.3%. The difference between protocols for some of the performance values were mainly due to cross-reactions with DNA from non-target species, which were either not tested or documented in the original articles. Considering that participating laboratories were free to use their own reagents and equipment, this study demonstrated that the diagnostic protocols for F. circinatum were not easily transferable to end-users. More generally, our results suggest that the use of protocols using conventional or real-time PCR outside their initial development and validation conditions should require careful characterization of the performance data prior to use under modified conditions (i.e. reagents and equipment). Suggestions to improve the transfer are proposed.This work was supported by COST action FP1406 Pinestrength . The work of the Estonian team was supported by the Estonian Science Foundation grants PSG136 and IUT21-04. The work of Portuguese team from INIAV was financed by INIAV I.P. Institute. The work at U. Aveiro (Portugal) was financed by European Funds through COMPETE and National Funds through the Portuguese Foundation for Science and Technology (FCT) to CESAM (UID/AMB/50017/2013 POCI-01- 0145-FEDER-007638). The work of Slovenian team was financed through Slovenian Research Agency (P4-0107) and by the Slovenian Ministry of Agriculture, Forestry and Food (Public Forestry Service). The British work was financially supported by the Forestry Commission, UK. The French work was financially supported by the French Agency for Food, environmental and occupational health safety (ANSES). The work in New Zealand was funded by Operational Research Programmes, Ministry for Primary Industries, New Zealand.Ioos, R.; Aloi, F.; Piskur, B.; Guinet, C.; Mullett, M.; Berbegal Martinez, M.; Bragança, H.... (2019). Transferability of PCR-based diagnostic protocols: An international collaborative case study assessing protocols targeting the quarantine pine pathogen Fusarium circinatum. Scientific Reports. 9:1-17. https://doi.org/10.1038/s41598-019-44672-8S1179Schmale, D. G. III & Gordon, T. R. Variation in susceptibility to pitch canker disease, caused by Fusarium circinatum, in native stands of Pinus muricata. Plant Pathol. 52, 720–725 (2003).Gordon, T. R., Kirkpatrick, S. C., Aegerter, B. J., Wood, D. L. & Storer, A. J. Susceptibility of Douglas fir (Pseudotsuga menziesii) to pitch canker, caused by Gibberella circinata (anamorph = Fusarium circinatum). Plant Pathol. 55, 231–237 (2006).Martínez‐Álvarez, P., Pando, V. & Diez, J. J. Alternative species to replace Monterey pine plantations affected by pitch canker caused by Fusarium circinatum in northern Spain. Plant Pathol. 63, 1086–1094, https://doi.org/10.1111/ppa.12187 (2014).Wingfield, M. J. et al. Pitch canker caused by Fusarium circinatum - a growing threat to pine plantations and forests worldwide. Australas. Plant Path. 37, 319–334 (2008).Bezos, D., Martinez-Alvarez, P., Fernandez, M. & Diez, J. J. Epidemiology and management of pine pitch canker disease in Europe - a review. Balt. For. 23, 279–293 (2017).Landeras, E. et al. Outbreak of pitch canker caused by Fusarium circinatum on Pinus spp. in Northern Spain. Plant Dis. 89, 1015 (2005).Bragança, H., Diogo, E., Moniz, F. & Amaro, P. First report of pitch canker on pines caused by Fusarium circinatum in Portugal. Plant Dis. 93, 1079–1079, https://doi.org/10.1094/PDIS-93-10-1079A (2009).EFSA. Risk assessment of Gibberella circinata for the EU territory and identification and evaluation of risk management options. EFSA Journal 8, 1620 (2010).Carlucci, A., Colatruglio, L. & Frisullo, S. First report of pitch canker caused by Fusarium circinatum on Pinus halepensis and P. pinea in Apulia (Southern Italy). Plant Dis. 91, 1683 (2007).Vettraino, A., Potting, R. & Raposo, R. EU legislation on forest plant health: an overview with a focus on Fusarium circinatum. Forests 9, 568 (2018).Möykkynen, T., Capretti, P. & Pukkala, T. Modelling the potential spread of Fusarium circinatum, the causal agent of pitch canker in Europe. Annals of Forest Sciences 72, 169–181 (2015).Bustin, S. A. et al. The MIQE guidelines: minimum information for publication of quantitative real-time PCR experiments. Clin Chem 55, https://doi.org/10.1373/clinchem.2008.112797 (2009).EPPO. PM 7/91(1): Gibberella circinata. EPPO Bull. 39, 298–309 (2009).ISTA. 7-009: Detection of Gibberella circinata on Pinus spp. (pine) and Pseudotsuga menziesii (Douglas-fir) seed. Validated Seed Health Testing Methods (2015).IPPC. ISPM 27, Diagnostic protocols for regulated pests, DP 22: Fusarium circinatum (2017).EPPO. PM 7/98 (2) Specific requirements for laboratories preparing accreditation for a plant pest diagnostic activity. EPPO Bull. 44, 117–147, https://doi.org/10.1111/epp.12118 (2014).Nirenberg, H. I. & O’Donnell, K. New Fusarium species and combinations within the Gibberella fujikuroi species complex. Mycologia 90, 434–458 (1998).Britz, H., Coutinho, T. A., Wingfield, M. J. & Marasas, W. F. O. Validation of the description of Gibberella circinata and morphological differentiation of the anamorph Fusarium circinatum. Sydowia 54, 9–22 (2002).Mullett, M., Pérez-Sierra, A., Armengol, J. & Berbegal, M. Phenotypical and molecular characterisation of Fusarium circinatum: correlation with virulence and fungicide sensitivity. Forests 8, 458 (2017).Herron, D. A. et al. Novel taxa in the Fusarium fujikuroi species complex from Pinus spp. Stud. Mycol. 80, 131–150, https://doi.org/10.1016/j.simyco.2014.12.001 (2015).Storer, G. & Clark, S. L. Association of the pitch canker fungus, Fusarium subglutinans f.sp. pini, with Monterey pine seeds and seedlings in California. Plant Pathol. 47, 649–656, https://doi.org/10.1046/j.1365-3059.1998.00288.x (1998).Schweigkofler, W., O’Donnell, K. & Garbelotto, M. Detection and quantification of airborne conidia of Fusarium circinatum, the causal agent of pine pitch canker, from two California sites by using a real-time PCR approach combined with a simple spore trapping method. Appl. Environ. Microbiol. 70, 3512–3520 (2004).Ramsfield, T. D., Dobbie, K., Dick, M. A. & Ball, R. D. Polymerase chain reaction-based detection of Fusarium circinatum, the causal agent of pitch canker disease. Molecular Ecology Resources 8, 1270–1273 (2008).Ioos, R., Fourrier, C., Iancu, G. & Gordon, T. R. Sensitive Detection of Fusarium circinatum in Pine Seed by Combining an Enrichment Procedure with a Real-Time Polymerase Chain Reaction Using Dual-Labeled Probe Chemistry. Phytopathology 99, 582–590, https://doi.org/10.1094/PHYTO-99-5-0582 (2009).Dreaden, T. J., Smith, J. A., Barnard, E. L. & Blakeslee, G. Development and evaluation of a real-time PCR seed lot screening method for Fusarium circinatum, causal agent of pitch canker disease. For. Path. 42, 405–411, https://doi.org/10.1111/j.1439-0329.2012.00774.x (2012).Fourie, G. et al. Culture-independent detection and quantification of Fusarium circinatum in a pine-producing seedling nursery. Southern Forests: a Journal of Forest Science 76, 137–143, https://doi.org/10.2989/20702620.2014.899058 (2014).Lamarche, J. et al. Molecular detection of 10 of the most unwanted alien forest pathogens in Canada using Real-Time PCR. PLoS ONE 10, e0134265, https://doi.org/10.1371/journal.pone.0134265 (2015).Luchi, N., Pepori, A. L., Bartolini, P., Ioos, R. & Santini, A. Duplex real-time PCR assay for the simultaneous detection of Caliciopsis pinea and Fusarium circinatum in pine samples. Applied Microbiology and Biotechnology 102, 7135–7146, https://doi.org/10.1007/s00253-018-9184-1 (2018).Sandoval-Denis, M., Swart, W. J. & Crous, P. W. New Fusarium species from the Kruger National Park, South Africa. MycoKeys 34, https://doi.org/10.3897/mycokeys.34.25974 (2018).Steenkamp, E. T., Wingfield, B. D., Desjardins, A. E., Marasas, W. F. & Wingfield, M. J. Cryptic speciation in Fusarium subglutinans. Mycologia 94, 1032–1043 (2002).Garcia-Benitez, C. et al. Proficiency of real-time PCR detection of latent Monilinia spp. infection in nectarine flowers and fruit. Phytopathologia Mediterranea 56, 242–250 (2017).Ebentier, D. L. et al. Evaluation of the repeatability and reproducibility of a suite of qPCR-based microbial source tracking methods. Water Research 47, 6839–6848, https://doi.org/10.1016/j.watres.2013.01.060 (2013).Bustin, S. & Huggett, J. qPCR primer design revisited. Biomolecular Detection and Quantification 14, 19–28, https://doi.org/10.1016/j.bdq.2017.11.001 (2017).Grosdidier, M., Aguayo, J., Marçais, B. & Ioos, R. Detection of plant pathogens using real-time PCR: how reliable are late Ct values? Plant Pathol. 66, 359–367, https://doi.org/10.1111/ppa.12591 (2017).Al-Soud, W. A. & Rådström, P. Capacity of nine thermostable DNA polymerases to mediate DNA amplification in the presence of PCR-inhibiting samples. Applied and environmental microbiology 64, 3748–3753 (1998).Saunders, G. C., Dukes, J., Parkes, H. C. & Cornett, J. H. Interlaboratory study on thermal cycler performance in controlled PCR and random amplified polymorphic DNA analyses. Clinical chemistry 47, 47–55 (2001).Boutigny, A.-L. et al. Optimization of a real-time PCR assay for the detection of the quarantine pathogen Melampsora medusae f. sp. deltoidae. Fungal Biology 117, 389–398, https://doi.org/10.1016/j.funbio.2013.04.001 (2013).Guinet, C., Fourrier-Jeandel, C., Cerf-Wendling, I. & Ioos, R. One-step detection of Monilinia fructicola, M. fructigena, and M. laxa on Prunus and Malus by a multiplex real-time PCR assay. Plant Dis. 100, 2465–2474, https://doi.org/10.1094/PDIS-05-16-0655-RE (2016).Aguayo, J. et al. Development of a hydrolysis probe-based real-time assay for the detection of tropical strains of Fusarium oxysporum f. sp. cubense race 4. PLoS ONE 12, e0171767, https://doi.org/10.1371/journal.pone.0171767 (2017).Broeders, S. et al. Guidelines for validation of qualitative real-time PCR methods. Trends in Food Science & Technology 37, 115–126, https://doi.org/10.1016/j.tifs.2014.03.008 (2014).Pelloux, H. et al. A second European collaborative study on polymerase chain reaction for Toxoplasma gondii, involving 15 teams. FEMS Microbiology Letters 165, 231–237, https://doi.org/10.1111/j.1574-6968.1998.tb13151.x (1998).Leslie, J. F. & Summerell, B. A. The Fusarium laboratory manual. (Blackwell Publishing, 2006).Ioos, R. et al. Test performance study of diagnostic procedures for identification and detection of Gibberella circinata in pine seeds in the framework of a EUPHRESCO project. EPPO Bull. 43, 267–275, https://doi.org/10.1111/epp.12037 (2013).Geiser, D. M. FUSARIUM-ID v. 1.0: a DNA sequence database for identifying Fusarium. Eur. J. Plant Pathol. 110, 473–479 (2004).White, T. J., Bruns, T., Lee, S. & Taylor, J. In PCR protocols: a guide to method and applications (eds Gelfand, D. H., Innis M. A., Sninsky, J. J. and White, T. J.) 315–322 (Academic Press, 1990).Nirenberg, H. I. A simplified method for identifying Fusarium spp. occurring on wheat. Canadian Journal of Botany 59, 1599–1609 (1981).Chabirand, A., Loiseau, M., Renaudin, I. & Poliakoff, F. Data processing of qualitative results from an interlaboratory comparison for the detection of “Flavescence dorée” phytoplasma: How the use of statistics can improve the reliability of the method validation process in plant pathology. PLoS ONE 12, e0175247, https://doi.org/10.1371/journal.pone.0175247 (2017).Loreti, S. et al. Performance of diagnostic tests for the detection and identification of Pseudomonas syringae pv. actinidiae (Psa) from woody samples. European Journal of Plant Pathology, https://doi.org/10.1007/s10658-018-1509-5 (2018).International Standardization Organization. ISO 16140:2003 Microbiology of food and animal feeding stuffs - Protocol for the validation of alternative methods (2003).Langton, S., Chevennement, R., Nagelkerke, N. & Lombard, B. Analysing collaborative trials for qualitative microbiological methods: accordance and concordance. International Journal of Food Microbiology 79, 175–181 (2002).R: A Language and Environment for Statistical Computing. R Foundation for Statistical Computing, Vienna (2014). R Foundation for Statistical Computing (2017).Wickham, H. ggplot2 : elegant graphics for data analysis. (Springer, 2016)

Commodity risk assessment of black pine (Pinus thunbergii Parl.) bonsai from Japan

The EFSA Panel on Plant health was requested to deliver a scientific opinion on how far the existing requirements for the bonsai pine species subject to derogation in Commission Decision 2002/887/EC would cover all plant health risks from black pine (Pinus thunbergii Parl.) bonsai (the commodity defined in the EU legislation as naturally or artificially dwarfed plants) imported from Japan, taking into account the available scientific information, including the technical information provided by Japan. The relevance of an EU-regulated pest for this opinion was based on: (a) evidence of the presence of the pest in Japan; (b) evidence that P.\ua0thunbergii is a host of the pest and (c) evidence that the pest can be associated with the commodity. Sixteen pests that fulfilled all three criteria were selected for further evaluation. The relevance of other pests present in Japan (not regulated in the EU) for this opinion was based on (i) evidence of the absence of the pest in the EU; (ii) evidence that P.\ua0thunbergii is a host of the pest; (iii) evidence that the pest can be associated with the commodity and (iv) evidence that the pest may have an impact in the EU. Three pests fulfilled all four criteria and were selected for further evaluation (Crisicoccus pini, Sirex nitobei and Urocerus japonicus). For the selected 19 pests, the risk mitigation measures proposed in the technical dossier were evaluated. Limiting factors on the effectiveness of the measures were documented. For each of the 19 pests, an expert judgement is given on the likelihood of pest freedom taking into consideration the risk mitigation measures acting on the pest, including any uncertainties. For all evaluated pests, the median likelihood of the pest freedom is 99.5% or higher and within the 90% uncertainty range it is 99% or higher

Impacts of climate change on plant diseases – opinions and trends

There has been a remarkable scientific output on the topic of how climate change is likely to affect plant diseases in the coming decades. This review addresses the need for review of this burgeoning literature by summarizing opinions of previous reviews and trends in recent studies on the impacts of climate change on plant health. Sudden Oak Death is used as an introductory case study: Californian forests could become even more susceptible to this emerging plant disease, if spring precipitations will be accompanied by warmer temperatures, although climate shifts may also affect the current synchronicity between host cambium activity and pathogen colonization rate. A summary of observed and predicted climate changes, as well as of direct effects of climate change on pathosystems, is provided. Prediction and management of climate change effects on plant health are complicated by indirect effects and the interactions with global change drivers. Uncertainty in models of plant disease development under climate change calls for a diversity of management strategies, from more participatory approaches to interdisciplinary science. Involvement of stakeholders and scientists from outside plant pathology shows the importance of trade-offs, for example in the land-sharing vs. sparing debate. Further research is needed on climate change and plant health in mountain, boreal, Mediterranean and tropical regions, with multiple climate change factors and scenarios (including our responses to it, e.g. the assisted migration of plants), in relation to endophytes, viruses and mycorrhiza, using long-term and large-scale datasets and considering various plant disease control methods