Wildfire promotes the invasion of Robinia pseudoacacia in the unmanaged Mediterranean Castanea sativa coppice forests

In the Mediterranean region of southern Europe, Castanea sativa Mill. (Castanea) coppice stands are being invaded by non-native pioneer tree species due to recurrent coppicing and wildfire disturbances. There is a need to control the spread of non-native tree species in Castanea coppices due to their pivotal socio-economic role, however, to facilitate this, further research into invasive strategies and their interactions with disturbances is required. The non-native Robinia pseudoacacia L. (Robinia) has widely colonized the overaged and unmanaged Castanea coppice forests in Vesuvius National Park, which were disturbed by the low-severity fires in the summer of 2017. Here, we aimed to assess the functional traits conferring a competitive advantage to the Robinia over Castanea and the changes in spatial stand patterns driven by wildfire disturbance. To achieve this we assessed the spatial stem patterns, regeneration strategies, and conducted field-assessments and remote sensing of the spring leaf phenology of both Castanea and Robinia in five 300–600 m2 plots. After the 2017 wildfire, root suckers constituted 72% (±12) of the Robinia vegetative living sprouts and occurred up to a distance of 10 m from the adult parent trees under the canopy of the Castanea trees. NDVI-based estimates at the start of the growing season (sos) in Castanea occurred over a 7 day period, from DOY 118–124, increasing at a rate (rsp) of 0.10–0.16, in agreement with the field-based assessment of spring leaf phenology. In Robinia, the sos estimated at DOY 109 from the NDVI seasonal trajectory disagreed with the field-based observations, which started later than Castanea, after approximately DOY 133. Here, the high percentage cover (∼90%) of the understory species influenced NDVI-based estimates of Robinia leaf spring phenology. The results suggest that low-severity wildfires increased the invasiveness of Robinia, and that vegetative regeneration strategies, rather than earlier spring phenology, conferred a competitive advantage in the fire-disturbed Castanea coppice stands. The results thus suggest that appropriate management of invasive Robinia trees to conserve the continuous canopy cover of Castanea stands should guide nature-based solutions to control the spread of non-native tree species

Can Peat Amendment of Mars Regolith Simulant Allow Soybean Cultivation in Mars Bioregenerative Life Support Systems?

Higher plants will play a key role in human survival in Space, being able to regenerate resources and produce fresh food. However, the creation of a fertile substrate based on extra-terrestrial soils is still a challenge for space cultivation. We evaluated the adaptability of soybean (Glycine max (L.) Merr.) cultivar ‘Pr91M10′ to three substrates, the Mojave Mars regolith Simulant MMS-1, alone (R100), and in a mixture with blond sphagnum peat at two different volumes, 85:15 (R85P15) and 70:30 (R70P30), in plants directly sown on the substrates or transplanted after sowing on peat. The low pH of peat (4.34) allowed the mitigation of the alkalinity of the Mars regolith simulant (pH 8.86), lowering the initial pH to neutral (6.98, R85P15), or subacid to neutral (6.33, R70P30) values. Seed germination reached the highest percentage in the shortest time in the mixture of regolith simulant with 15% of peat. The cultivation substrate did not affect the plant growth and nutritional status. However, a significant interaction between the substrate and planting method was found in several growth parameters, with the highest positive effects observed in plants resulting from direct sowing on the regolith mixture with peat

Green compost amendment improves potato plant performance on Mars regolith simulant as substrate for cultivation in space

Background and Aims: Higher plants represent an optimal tool to regenerate resources while producing food in Space. However, the configuration of fertile cultivation substrates based on extraterrestrial resources is still a challenge. We evaluated the adaptability of potato (Solanum tuberosum L., cv. ‘Colomba’) to the growth on six substrates: the MMS-1 Mars regolith simulant, alone (R100) and in mixture with 30% in vol. of green compost (R70C30), a fluvial sand, alone or mixed with 30% of compost (S100 and S70C30), a red soil from Sicily (RS), and a volcanic soil from Campania (VS). Methods: We assessed the physicochemical properties of the substrates, and the physiological and biometric parameters of potato plants grown in pot on these substrates, in cold glasshouse. Results: Both R100 and S100 were alkaline (pH ≥8.6) and coarse-textured, lacking organic matter and pivotal macronutrients. The amendment with compost significantly lowered their alkaline pH and improved the chemical fertility. The sandy-loam textured VS was sub-alkaline, slightly calcareous, with higher organic C and nutrient availability than RS. This latter was neutral-to-sub-alkaline, clay textured, poorly calcareous, with significantly higher CEC than VS. Leaf CO2 assimilation rate was higher in plants grown in terrestrial soils and S100. Plant growth was greater in VS, R70C30 and S70C30, while it was reduced on R100. Plants produced healthy tubers on all the substrates. Conclusion: MMS-1 regolith simulant was found poor in nutrients and unsuitable to sustain adequately the plant growth. Amendment with organic compost improved MMS-1 physiochemical properties and fertility and plant performance

Tocilizumab for patients with COVID-19 pneumonia. The single-arm TOCIVID-19 prospective trial

BackgroundTocilizumab blocks pro-inflammatory activity of interleukin-6 (IL-6), involved in pathogenesis of pneumonia the most frequent cause of death in COVID-19 patients.MethodsA multicenter, single-arm, hypothesis-driven trial was planned, according to a phase 2 design, to study the effect of tocilizumab on lethality rates at 14 and 30 days (co-primary endpoints, a priori expected rates being 20 and 35%, respectively). A further prospective cohort of patients, consecutively enrolled after the first cohort was accomplished, was used as a secondary validation dataset. The two cohorts were evaluated jointly in an exploratory multivariable logistic regression model to assess prognostic variables on survival.ResultsIn the primary intention-to-treat (ITT) phase 2 population, 180/301 (59.8%) subjects received tocilizumab, and 67 deaths were observed overall. Lethality rates were equal to 18.4% (97.5% CI: 13.6-24.0, P=0.52) and 22.4% (97.5% CI: 17.2-28.3, P<0.001) at 14 and 30 days, respectively. Lethality rates were lower in the validation dataset, that included 920 patients. No signal of specific drug toxicity was reported. In the exploratory multivariable logistic regression analysis, older age and lower PaO2/FiO2 ratio negatively affected survival, while the concurrent use of steroids was associated with greater survival. A statistically significant interaction was found between tocilizumab and respiratory support, suggesting that tocilizumab might be more effective in patients not requiring mechanical respiratory support at baseline.ConclusionsTocilizumab reduced lethality rate at 30 days compared with null hypothesis, without significant toxicity. Possibly, this effect could be limited to patients not requiring mechanical respiratory support at baseline.Registration EudraCT (2020-001110-38); clinicaltrials.gov (NCT04317092)