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Europe is the largest producer of wheat, the second most widely grown cereal crop after rice. The increased occurrence and magnitude of adverse and extreme agroclimatic events are considered a major threat for wheat production. We present an analysis that accounts for a range of adverse weather events that might significantly affect wheat yield in Europe. For this purpose we analysed changes in the frequency of the occurrence of 11 adverse weather events. Using climate scenarios based on the most recent ensemble of climate models and greenhouse gases emission estimates, we assessed the probability of single and multiple adverse events occurring within one season. We showed that the occurrence of adverse conditions for 14 sites representing the main European wheat-growing areas might substantially increase by 2060 compared to the present (1981–2010). This is likely to result in more frequent crop failure across Europe. This study provides essential information for developing adaptation strategies. Studies into the effects of climate change on crop yields have tended to focus on the average state of the climate. Now, research into the effects of adverse weather events on wheat yields in Europe suggests that the probability of single and multiple adverse events occurring within a season is expected to increase substantially by the year 2060.

Fungi play central roles in many biological processes, influencing soil fertility, decomposition, cycling of minerals, and organic matter, plant health, and nutrition. They produce a wide spectrum of molecules, which are exploited in a range of industrial processes to manufacture foods, food preservatives, flavoring agents, and other useful biological products. Fungi can also be used as biological control agents of microbial pathogens, nematodes or insect pests, and affect plant growth, stress tolerance, and nutrient acquisition. Successful exploitation of fungi requires better understanding of the mechanisms that fungi use to cope with stress as well as the way in which they mediate stress tolerance in other organisms. It is against this backdrop that a scientific meeting on fungal stress was held in São José dos Campos, Brazil, in October 2014. The meeting, hosted by Drauzio E. N. Rangel and Alene E. Alder-Rangel, and supported by the São Paulo Research Foundation (FAPESP), brought together more than 30 young, mid-career, and highly accomplished scientists from ten different countries. Here we summarize the highlights of the meeting.

A thorough density functional theory study is performed for the three carboxyl-based derivatives of the exTTF-TCF chromophore, where the π-extended tetrathiafulvalene (exTTF) electron-donor is linked to the tricyanofuran (TCF) electron-acceptor through an ethylene bridge, as dyes for dye-sensitized solar cells. Calculations predict that the carboxyl group in the acceptor moiety adopts an adequate orientation for an efficient anchoring on the semiconductor TiO₂ surface. The carboxylic acid group holds a negative charge twice larger than the cyano moiety that favors the electron injection to the semiconductor. Time-dependent calculations allow for the assignment of the absorption bands in the UV-vis spectrum of exTTF-TCF and confirm the presence of two low-lying charge-transfer electronic transitions that account for the moderately-intense absorption in the 450-800 nm range. The striking optical absorption properties of exTTF-TCF are preserved for the carboxylic analogues. Finally, periodic calculations show relevant topological differences between the carboxylic derivatives anchored on the TiO₂ surface, which would notably influence in the power conversion efficiency of a dye-sensitized solar cell.

The present work investigates the thermochemical valorization of camelina straw, which is a waste generated during the harvesting of Camelina sativa, an oilseed crop for the production of biodiesel or hydrotreated vegetable oil (HVO). In particular, it is focused on obtaining bio-oil via thermal or catalytic fast pyrolysis, which would be the first stage on a sequence of chemical processes for biofuel production. The catalytic interference of the inorganic matter present in the biomass was studied by preparing a batch of de-ashed camelina straw by washing with diluted nitric acid. Chemical analysis revealed this treatment effectively removed alkaline (K and Na) and alkaline earth (Ca and Mg) metals. Pyrolysis of de-ashed camelina straw led to higher mass and energy yields of bio-oil in water-free basis (bio-oil*), but with higher oxygen concentration. Catalytic pyrolysis over HZSM-5 was also studied in both raw and de-ashed feedstocks. This catalyst promoted mainly decarbonylation and decarboxylation reactions of the pyrolysis vapors, leading to much higher gas yields and lower of bio-oil*, but with better quality. Catalytic pyrolysis of untreated camelina straw exhibited a synergetic effect between both the inorganic matter and the external HZSM-5 catalyst, so that bio-oil* yield was the lowest (20 wt%) due to an extensive deoxygenation (18 wt% oxygen content), which resulted in the highest HHV obtained (37.3 MJ/kgdb). Significant differences were also found on the molecular composition of the bio-oils* with larger proportion of anhydro sugars when the biomass was de-ashed, while HZSM-5 strongly promoted the formation of oxygenated aromatics and aromatic hydrocarbons.

Instruction memory organisations have been pointed out as one of the major sources of energy consumption in embedded systems. As embedded systems are characterised by restrictive resources and a low-energy budget, any enhancement that is introduced into this component of the system will allow embedded designers not only to decrease the total energy consumption, but also to have a better distribution of the energy budget throughout the whole system. The work that is presented in this paper provides a synthesis on the low-energy techniques that are used in instruction memory organisations, outlining their comparative advantages, drawbacks, and trade-offs. Apart from giving the reader a first grasp on the fundamental characteristics and design constraints of various types of instruction memory organisations, the architectural classification that is presented in this paper has the advantage of clearly exhibiting lesser explored techniques, and hence providing hints for future research on instructions memory organisations that are used in embedded systems.

The decline of arable species characteristic of winter cereal fields has often been attributed to different factors related to agricultural intensification but most importantly to herbicide use. Herbicide phytotoxicity is most frequently assessed using short-term endpoints, primarily aboveground biomass. However, short-term sensitivity is usually not sufficient to detect actual effects because plants may or may not recover over time following sublethal herbicide exposures. Therefore, it is important to assess the long-term effects of herbicide applications. Annual species rely on renewable seed production to ensure their persistence; hence, assessment of herbicide sensitivity is more accurately estimated through effects on reproduction. Here we aim to assess the phytotoxicity of two commonly used herbicides: tribenuron and 2,4-D on eight plant species belonging to four families, each with one rare and one more common species. Specifically we examined the pattern of sensitivity using short-term and long-term endpoints (total aboveground biomass, total seed biomass and number of seeds) of these species; we determined the levels of and time to recovery in terms of stem length and fruit number, and assessed whether their rarity relates to their sensitivity to herbicide application. Our results suggest that although differences in herbicide sensitivity are not a direct cause of rarity for all species, it may be an important driver of declining arable plants.

The reactivity of Cu, Ag, and Au nanoparticles and of the corresponding (111) surfaces of these elements toward CO oxidation and NO(2) reduction has been investigated by means of DFT and DFT-D calculations. The co-adsorption energies of CO and O on Ag and Au surfaces are smaller than that corresponding to Cu surface but the oxidation reaction is energetically more favored for the heavier metals. The adsorption energy of NO(2), E(ads), is about 50 % larger on nanoparticles than on the metal perfect surfaces, following the almost general rule stating that the lower coordinated sites are those where the interaction is the largest. Interestingly for the co-adsorption and oxidation of CO an increase of reactivity is found for the Au nanoparticles, which is attributed to the large number of low coordinated sites due to the specific shape of this nanoparticle induced by the adsorbates.

We evaluated the effect of compost amendment and/or bacterial inoculants on the growth and metal accumulation of Salix caprea (clone BOKU 01 AT-004) and Nicotiana tabacum (in vitro-bred clone NBCu10-8). Soil was collected from an abandoned Pb/Zn mine and rhizobacterial inoculants were previously isolated from plants growing at the same site. Plants were grown in untreated or compost-amended (5% w/w) soil and were inoculated with five rhizobacterial strains. Non-inoculated plants were also established as a control. Compost addition increased the shoot DW yield of N. tabacum but not S. caprea, while it decreased soil metal availability and lowered shoot Cd/Zn concentrations in tobacco plants. Compost amendment enhanced the shoot Cd/Zn removal due to the growth promotion of N. tabacum or to the increase in metal concentration in S. caprea leaves. Bacterial inoculants increased photosynthetic efficiency (particularly in N. tabacum) and sometimes modified soil metal availability, but this did not lead to a significant increase in Cd/Zn removal. Compost amendment was more effective in improving the Cd and Zn phytoextraction efficiency than bioaugmentation.