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Abstract PurposeBinucleate Rhizoctonia sp. (BNR), indigenous to old olive groves of the Apulia region (Southern Italy), and its relationship with olive trees were investigated to search for beneficial soil microorganisms suitable for supporting plant growth and crop productions in degraded semi-arid soils.MethodsBinucleate Rhizoctonia sp. was first isolated from five ancient olive groves using olive tree plantlets as \"living baits\". The functional relationship of BNR with olive trees was estimated with in-pot growth assays, using native soil amended with an artificial inoculum from the native BNR isolates. BNR was then quantified in the olive groves by digital PCR using a TaqMan assay specifically designed on the ITS regions of the native AG-A isolates.ResultsDigital PCR was able to discriminate BNR (Ceratobasidium sp.) from the phylogenetically close Basidiomycetes such as Rhizoctonia solani (Thanatephorus cucumeris). This assay detected an amount of BNR in five olive groves ranging from traces up to 105 target gene copies per µL of DNA. When artificially added to native soil samples, BNR AG-A increased olive tree growth by 50% and 25% respectively under constant optimal water availability and repeatedly induced water stress. Indole-3-acetic acid production was demonstrated for the BNR AG-A isolates, thus, in part, explaining growth promotion.ConclusionThanks to the absolute quantification of fungal DNA fragments in soil with digital PCR, findings suggest that new soil functional indicators, such as the growth promoting Rhizoctonia AG-A, may be identified with this research approach to be investigated as a biotic resource for enhancing soil ecosystem services.

Background This study started from typical replant disease symptoms limited to specific foci within three multigeneration orchards showing homogeneous growth. Methods A plant growth assay was conducted using soil from symptomatic and asymptomatic tree root zones along planted rows and from strip-rows. Root colonizing fungal communities were investigated, then the study turned to pathogenicity of Cylindrocarpon-like fungi (Dactylonectria and Ilyonectria spp) and their extracellular exudates. Results Growth of apple rootstock plantlets in soil from symptomatic trees was significantly lower than in those observed in soil from asymptomatic trees and from striprows. Among the main group of endophytic filamentous fungi isolated from roots, Cylindrocapon-like fungi (Dactylonectria torresensis and, to a lesser extent, Ilyonectria robusta), along with binucleate Rhizoctonia spp., prevailed mostly in plantlets grown in soil collected from planted rows. On the other hand, Fusarium spp. prevailed in plantlets grown in soil from the strip-rows. Cylindrocarpon-like fungi was found to be the most negatively correlated with plant growth. As findings of artificial inoculation with main root colonizing fungal species were not in line with what was observed in native soils, a further investigation was performed on secondary metabolites through which Dactylonectria torresensis exerts pathogenicity; this analysis revealed that both Phytotoxins (tentoxin, HC toxin and zearalenone) and cytotoxic compounds (rabelomycin and nidulin) may be involved. Conclusion Findings suggest that extracellular compounds released by D. torresensis may have contributed to the severe growth reduction associated with replant disease-like symptoms.

Composting technologies have progressed parallel to the growing interest in recycling organic waste over recent decades, whilst in-field compost application requires technical improvement and more experience in order to optimize their effect according to the agro-environment and the type of crop which follow their incorporation into the soil. In response to compost application, biological soil features were assessed in field by adopting precision agricultural machinery and by limiting soil incorporation to a depth of 15 cm. A 2-year trial was carried out on two sites in the East Po valley (Northern Italy), an agricultural district which, in 2000, was classified as being on the verge of desertification, and where efforts to counteract soil organic matter decline have been underway for some decades. A green-waste compost produced in accordance with current national directives was applied in autumn 2019 and 2020 to two organic fields using precision farming machinery for compost spreading and conventional harrows for incorporation. Fields were divided into two large plots to compare the effect of compost treatment to an untreated control and were managed according to organic farming practices. Seven months after application, microbial biomass, assessed in terms of DNA, and 17 enzymatic activities were estimated by sampling root-explored soil at the vegetative stage of different seed crops for organic horticulture. A significant overall increase of biological soil activity was detected after the second application. The qualitative response varied slightly between the two sites: a higher impact of microbial biomass was observed in the site that was poorer in soil organic matter; whilst in the other, an increase of phosphatase activities contributed more to the general increase of biological activity. Findings show that, in those agricultural soils, an agronomic advantage from compost can be obtained only after repeated applications; furthermore, precision farming technologies facilitate compost application even in small, specialized farms such as those which hosted this trial.

Background and aims A study was performed to investigate the role of fungal metabolites released into the rhizosphere of replanted orchards as a potential biotic component of tree growth decline. Methods The phytotoxicity of the gamma ray-sterilized crude culture filtrates of sixteen fungal species originating from replanted apple orchards was tested in a bioassay. Low molecular weight compounds released by Fusarium spp. were analyzed. Results The fungal culture filtrates affected seedling growth and health with an activity that varied from growth inhibition to promotion. Three out of the six species of Fusarium tested produced species-specific mycotoxins such as equisetin and enniatin B and D (<1 μg ml⁻¹ and <6 μg ml⁻¹, respectively) associated with root-tip necrosis, whereas fusaric acid (80–230 μg ml⁻¹) was associated with asymptomatic plant growth inhibition. These findings were consistent with those obtained using pure compounds. Moreover, methoxyconidiol, paecilaminol, integrastatin B and other biologically active compounds, whose fungal origin and phytotoxicity have not yet been reported, were found. in all fungal filtrates. Conclusions Findings suggest that i) phytopathogenicity of soil borne fungi can be expressed regardless of root infection; ii) a synergistic interaction between cooccurring mycotoxins and other biologically active compounds may explain plant growth inhibition. Iii) fungal metabolites released into soil may represent an underestimated component of nonspecific replant disease.

Intervention to achieve alcohol abstinence represents the most effective treatment for alcohol-dependent patients with liver cirrhosis; however, anticraving drugs might worsen liver disease. We aimed to investigate the effectiveness and safety of baclofen in achieving and maintaining alcohol abstinence in patients with liver cirrhosis. Between October, 2003, and November, 2006, 148 alcohol-dependent patients with liver cirrhosis were referred to the Institute of Internal Medicine, Rome, Italy. 84 were randomly allocated either oral baclofen or placebo for 12 weeks. Primary outcome was proportion of patients achieving and maintaining alcohol abstinence. Measures of this outcome were total alcohol abstinence and cumulative abstinence duration, which were assessed at outpatient visits. Relapse was defined as alcohol intake of more than four drinks per day or overall consumption of 14 or more drinks per week over a period of at least 4 weeks. Analysis was by intention to treat. This study is registered with ClinicalTrials.gov, number NCT00525252. Of 42 patients allocated baclofen, 30 (71%) achieved and maintained abstinence compared with 12 (29%) of 42 assigned placebo (odds ratio 6·3 [95% CI 2·4–16·1]; p=0·0001). The number of dropouts (termination of treatment) did not differ between the baclofen (6/42 [14%]) and placebo (13/42 [31%]) groups (p=0·12). Cumulative abstinence duration was about twofold higher in patients allocated baclofen than in those assigned placebo (mean 62·8 [SE 5·4] vs 30·8 [5·5] days; p=0·001). No hepatic side-effects were recorded. Baclofen is effective at promoting alcohol abstinence in alcohol-dependent patients with liver cirrhosis. The drug is well tolerated and could have an important role in treatment of these individuals.

Soil suppressiveness which is the natural ability of soil to support optimal plant growth and health is the resultant of multiple soil microbial components; which implies many difficulties when estimating this soil condition. Microbial benefits for plant health from repeated digestate applications were assessed in three experimental sites surrounding anaerobic biogas plants in an intensively cultivated area of northern Italy. A 2-yr trial was performed in 2017 and 2018 by performing an in-pot plant growth assay, using soil samples taken from two fields for each experimental site, of which one had been repeatedly amended with anaerobic biogas digestate and the other had not. These fields were similar in management and crop sequences (maize was the recurrent crop) for the last 10 yr. Plant growth response in the bioassay was expressed as plant biomass production, root colonization frequency by soil-borne fungi were estimated to evaluate the impact of soil-borne pathogens on plant growth, abundance of Pseudomonas and actinomycetes populations in rhizosphere were estimated as beneficial soil microbial indicators. Repeated soil amendment with digestate increased significantly soil capacity to support plant biomass production as compared to unamended control in both the years. Findings supported evidence that this increase was principally attributable to a higher natural ability of digestate-amended soils to reduce root infection by saprophytic soil-borne pathogens whose inoculum was increased by the recurrent maize cultivation. Pseudomonas and actinomycetes were always more abundant in digestate-amended soils suggesting that both these large bacterial groups were involved in the increase of their natural capacity to control soil-borne pathogens (soil suppressiveness).

The surveys of the excavation area of the Pauciuri archaeological site, carried out with geomatic techniques, are described. 3D models of the site and of some particularly interesting remains have been obtained. For an early medieval burial both TLS and photogrammetric surveys were carried out, which allowed the development of two 3D models. The comparison between the two techniques has been made: the results are discussed.

In this paper, a new methodology supporting the design of landing gears is proposed. Generally, a preliminary step is performed with simplified FE model, usually one-dimensional, to achieve the reaction forces involving each component during all aforementioned aircraft operations. Though this approach gives a valid support to the designer, it is characterized by several problems, such as the related approximations. So, it is important, by a numerical point of view, to develop an isostatic FE model equivalent to the real one. In fact, if the landing gear is modelled as hyperstatic, the static equilibrium equations are insufficient for determining the internal forces and reactions on each sub-component; so, the modelled material properties and geometries assume an increasing importance, which gets the model too approximating. The proposed methodology consists of achieving the reaction forces by means of multibody simulations, by overcoming such problems, since each component is modelled as rigid. In this paper, also a FE model for the investigation of the structural response is proposed. Aimed to Certification by Analysis purposes, the developed multibody and the FE models have been assessed against an experimental landing gear drop test carried out by Magnaghi Aeronautica S.p.A., according to the EASA CS 25 regulations.

The investigation of the mechanical response of fibre-reinforced composite laminates under impact loads can be very difficult due to the occurrence of simultaneous failure phenomena. Indeed, as a consequence of low velocity impacts, intra-laminar damages, like fibre and matrix cracking, and inter-laminar damages, such as delaminations, can take place simultaneously. These damage mechanisms can lead to significant reductions in strength and stability of the composite structure. In this paper a joint numerical-experimental study is proposed which, by means of non-destructive testing techniques (Ultra-sound and thermography) and non-linear explicit FEM analyses, aims to completely characterise the impact induced damage in composite laminates under low velocity impacts. Indeed the proposed numerical tool has been used to improve the understanding of the experimental data obtained by Non-Destructive Techniques. Applications on samples tested according to the AECMA (European Association of Aerospace Manufacturers) prEn6038 standard at three different impact energies are presented. The interaction between numerical and experimental investigation allowed to obtain an exhaustive insight on the different phases of the impact event considering the inter-laminar damage formation and evolution.

Usually during the design of landing gear, simplified Finite Element (FE) models, based on one-dimensional finite elements (stick model), are used to investigate the in-service reaction forces involving each subcomponent. After that, the design of such subcomponent is carried out through detailed Global/Local FE analyses where, once at time, each component, modelled with three-dimensional finite elements, is assembled into a one-dimensional finite elements based FE model, representing the whole landing gear under the investigated loading conditions. Moreover, the landing gears are usually investigated also under a kinematic point of view, through the multibody (MB) methods, which allow achieving the reaction forces involving each subcomponent in a very short time. However, simplified stick (FE) and MB models introduce several approximations, providing results far from the real behaviour of the landing gear. Therefore, the first goal of this paper consists of assessing the effectiveness of such approaches against a 3D full-FE model. Three numerical models of the main landing gear of a regional airliner have been developed, according to MB, “stick,” and 3D full-FE methods, respectively. The former has been developed by means of ADAMS® software, the other two by means of NASTRAN® software. Once this assessment phase has been carried out, also the Global/Local technique has verified with regard to the results achieved by the 3D full-FE model. Finally, the dynamic behaviour of the landing gear has been investigated both numerically and experimentally. In particular, Magnaghi Aeronautica S.p.A. Company performed the experimental test, consisting of a drop test according to EASA CS 25 regulations. Concerning the 3D full-FE investigation, the analysis has been simulated by means of Ls-Dyna® software. A good level of accuracy has been achieved by all the developed numerical methods.