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Plant autoecology and population genetics provide a perspective on the likelihood of natural regeneration, which is critical when designing conservation strategies for endangered species. The threatened coastal plant Malcolmia littorea (Brassicaceae) was sampled across its European distribution and studied for genetic diversity and seed fitness, with the aim of providing information for the conservation of isolated and declining populations., Nine microsatellite markers (five chloroplast and four nuclear) were analysed to assess population genetic diversity and structure and to conduct a spatial analysis using the software DIVA-GIS. Germination percentages and rates were assessed by incubating the seeds under eight constant temperatures (0-27 °C)., The genetic diversity was found to be similar among subpopulations (chloroplast H = 0.04-0.17; nuclear Ho = 0.20-0.37), with no correlation between subpopulation diversity and the area of occupancy (AOO). The subpopulations were found to be clustered in three genetic groups, and three of them were identified as conservation priorities due to their unique genetic composition. The germination study revealed a significant influence of the maternal environment and AOO on seed germination, with the smaller subpopulations showing lower germination percentages ( P < 0.05)., These results highlight the importance of obtaining information on isolated subpopulations through different experimental approaches ( e.g. seed germination plus population genetics) to enable planning of effective conservation actions. For M. littorea, seed collection for both in situ and ex situ conservation should take into account the local adaptation of the subpopulation and the genetic structure of the species. [ABSTRACT FROM AUTHOR]

Integral test facilities (ITFs) are one of the main tools for the validation of best estimate thermalhydraulic system codes. The experimental data are also of great value when compared to the experiment-scaled conditions in a full NPP. The LOBI was a single plus a triple-loop (simulated by one loop) test facility electrically heated to simulate a 1300MWe PWR. The scaling factor was 712 for the core power, volume, and mass flow. Primary and secondary sides contained all main active elements. Tests were performed for the characterization of phenomenologies relevant to large and small break LOCAs and special transients in PWRs. The paper presents the results of three posttest calculations of LOBI experiments. The selected experiments are BL-30, BL-44, and A1-84. They are LOCA scenarios of different break sizes and with different availability of safety injection components. The goal of the analysis is to improve the knowledge of the phenomena occurred in the facility in order to use it in further studies related to qualifying nodalizations of actual plants or to establish accuracy data bases for uncertainty methodologies. An example of procedure of implementing changes in a common nodalization valid for simulating tests occurred in a specific ITF is presented along with its confirmation based on posttests results. [ABSTRACT FROM AUTHOR]

European chestnut ( Castanea sativa) is an important multipurpose tree that has been cultivated for wood and fruit in the Mediterranean basin since ancient times. Cultivation of traditional chestnut varieties has a long tradition in Italy, where cultivars have been selected over centuries as a function of the best nut traits. In this study, 94 grafted chestnuts corresponding to 26 representative cultivars from Italy were evaluated by seven simple sequence repeat (SSR) markers to establish whether they corresponded to varieties in the narrow sense. The results allowed 20 genotypes to be identified that corresponded to the same number of clones. In total, 52 alleles were identified, eight of which were exclusive. Cases of homonymies and synonymies were detected. Moreover, our results highlighted a considerable genetic uniformity among ‘Marrone-type’ cultivars and, on the contrary, a high genetic diversity among the evaluated cultivars demonstrating that this is a valuable germplasm and an important genetic resource to be preserved. [ABSTRACT FROM AUTHOR]

The maintenance of plant genetic resources requires the identification of places and agroforestry systems that support high levels of genetic diversity. The aim of this work was to clarify the number and names of chestnut ( Castanea sativa) cultivars in the south of Spain. Accordingly, 100 grafted chestnut trees corresponding to 34 traditional names were evaluated using 10 qualitative morphological traits and seven simple sequence repeat (SSRs) markers. We identified 38 varieties, 12 in the Huelva region and 26 in Malaga, and synonymies and homonymies were discussed. This work demonstrated that the joint use of morphological traits and SSR markers is an efficient method to evaluate the agrobiodiversity of chestnut in this region. It was also stated that chestnut production in the south of Spain is a traditional system using varieties developed ‘ in situ’. This constitutes a genuine system of on-farm conservation, which is now threatened. Consequently, adopting strategies for its safeguarding are urgently recommended. [ABSTRACT FROM AUTHOR]

The article focuses on the use of the natural circulation flow map for the evaluation of the natural circulation systems. It discusses the work done to build and develop an engineering tool related to the natural circulation conducted at the University of Pisa in Italy. It explores the different loop flow regimes in single phase and in two phase, as well as the derivation of a suitable tool to judge the natural circulation performance in a generic system. It highlights the comparison among the natural circulation performance of various nuclear power plants having different designs done to show a practical application of the natural circulation flow map.

The article presents a review of an investigation study on accident management in VVER-1000 reactor type which was conducted in the framework of a European Commission funded project. It looks into wide-ranged analysis of accident management in VVER-1000, with main regard to the qualification of the computational tool utilized in the study. The proposal for an optimal accident management strategy for this kind of nuclear power plant which involved the depressurization of steam generators and primary system depressurization is also discussed.

The article focuses on the thermal-hydraulic analysis of coolant flow in the Smolensk-3 RBMK nuclear power plant (NPP). The coolant flow rate blockage of group distribution header (GDH) could lead an excessive heat-up of the pressure tubes and multiple fuel channels (FC) ruptures. The study applied the concept of neutron kinetic models. It is found that the mass flow rate is altered according to the power distribution which established in the schematization of FC. In addition, the author asserts that the time of oscillations in mass flow rate is dependent to the attributed power of FC.