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Background and aims The use of root-associated microorganisms emerge as a sustainable tool to enhance crop tolerance and productivity under climate change, particularly in drought-affected areas. Here, the impact of an inoculum based on arbuscular mycorrhizal fungi (AMF) was evaluated on pepper (Capsicum annuum L.) cultivation at varying water irrigation treatments (well-watered, reduced irrigation and rain-fed) under open-field conditions. Methods Agronomic and ecophysiological parameters, as well as biochemical analyses on stress markers and phytohormones in leaves and on fruit quality traits, were evaluated, along with the shifts in soil- and root-associated microbial communities. Results Rain-fed water treatment caused reduced fruit sizes, while no differences were detected among well-watered and reduced irrigation. Reduced irrigation did not cause a reduction in stomatal conductance. The highest AM fungal colonization rates were observed under reduced irrigation, and the enhanced flavonoid content and reduced oxidative stress markers in AMF-inoculated plants suggested a synergistic effect of AM fungal inoculation in boosting plant tolerance against stress. A shift in microbial community composition in the different irrigation treatments, associated with different enzymatic activity, highlighted the potential role of microbial dynamics in plant stress response under water-limited conditions. Conclusion The study suggests that a reduced irrigation comes along with beneficial impacts on pepper root associated microbes, while not impairing crop performance and yields, indicating a potential of saving water. All together, our results imply that optimization of irrigation and beneficial plant-microbe interactions, such as AM fungal symbiosis, can improve pepper physiological and productivity features under climate change.

Incidence and risk factors associated with the development of pressure ulcers in an Italian general intensive care unit. INTRODUCTION: Pressure ulcers (PU) represent one of the most frequent adverse event in intensive care units (ICU). Critical patients are at higher risk of developing a PU, with an incidence between 3.3-39.3%. AIM: To assess the incidence and risk factors for developing PUs in a general ICU of an Italian University hospital. METHODS: Retrospective observational study on a sample of 122 patients admitted to a general intensive care unit, from January to December 2015, with a length of ICU stay > 5 days. PUs were stadied according to the National Pressure Ulcer Advisory Panel. RESULTS: One hundred and twenty two patients were enrolled. The incidence of PUs was 33%, and the incidence rate was 23 PUs for 1.000 days of ICU stay; 29% of PUs were of stage I, 56% of stage II, 8% stage III and 6% stage IV. PUs mainly affected the sacrum (21%) with a very low incidence in the heels (1.6%). Despite several factors were associated to the development of PUs (being female, Sequential Organ Failure Assessment, length of stay, mechanical ventilation > 72 hours, administration of dobutamine, Admission pO 2/FiO2 ratio, mean Braden during ICU stay and admission diagnosis) only ICU lenght of day remained statistically significant. CONCLUSIONS: The incidence of PUs is comparable to other recent studies. Many factors are potentially involved in the onset of PUs. Identifying these factors can help nurses to plan interventions to prevent their development.

We propose a new numerical approach for the solution of the 2D acoustic wave equation to model the predicted data in the field of active-source seismic inverse problems. This method consists in using an explicit finite difference technique with an adaptive order of approximation of the spatial derivatives that takes into account the local velocity at the grid nodes. Testing our method to simulate the recorded seismograms in a marine seismic acquisition, we found that the low computational time and the low approximation error of the proposed approach make it suitable in the context of seismic inversion problems.

Finding an efficient procedure to solve a seismic inversion problem, such as Full Waveform Inversion, still remains an open question. This is mainly due to the non linearity of the misfit function, characterized by the presence of multiple local minima, that cause unsuccessful results of local optimization strategies when the starting model is not in the basin of attraction of the global minimum. Therefore, the use of a global optimization strategy in order to estimate a suitable starting velocity model for Full Waveform Inversion is a crucial point. In this work we propose a new method which is based on the application of the Adaptive Simulated Annealing algorithm using a coarse inversion grid, different from the domain modelling one, that allows the reduction of the number of unknowns. Numerical results show that the application of our strategy to an acoustic Full Waveform Inversion provides a good starting model for a local optimization procedure, lying in the basin of attraction of the global minimum.