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Improving the soil health before native plant reintroduction: a pipeline for the restoration of plant habitats.
No full textSoils are the fundament of terrestrial ecosystems, playing a key role in habitat formation and maintenance. Soils host
a huge variety of life forms (bacteria, fungi, protozoa, and animals), many of which establish close relationships with
plants, the most represented taxa in soil. The interactions between plant roots and soil create favorable physical and
chemical conditions, which are essential for both plant growth and reproduction, and for soil health maintenance.
Such a relationship depends on the plant community composition, and environment disturbance may easily bring to
the disruption of such an equilibrium. Plant conservation is tightly connected with the conservation of habitats, so
the success of restoration actions largely depends on the restoration of a rich and diverse belowground life, which in
turn is sustained by a healthy soil in terms of mineral nutrients, organic matter, and bearable presence of xenobiotic
substances. Actions for an efficient plant conservation should thus start from the requalification of soil health. The
maintenance or restoration of over-exploited soils according to ecological principles has been recognized a pillar for
future agriculture and large efforts have been dedicated to developing sustainable soil and crop management practices
and identifying the most appropriate and measured inputs of either organic or mineral fertilizers. The European
Soil Mission defines ‘healthy’ the soil with a continued capacity to support ecosystem services and indicates the
improvement of soil structure and concentration of the stable soil organic carbon as necessary to enhance habitat
quality for soil biota and crops. The restoration of soil in natural ecosystems pose special challenges, because of the
need to limit soil disturbance, to reduce the input of xenobiotic and to avoid or limit the introduction of alien organisms,
primary plants, which could become direct competitors of the target species or change habitat conditions.
We present here a pipeline of actions developed for the establishment of native trees on a degraded sandy soil, which
starts from the restoration of soil health and the establishment of a ground vegetation cover prior the transplanting of
target shrubs and trees. Preliminary actions should assess the soil physical, chemical, and biological properties, and
the abundance and composition of the soil seed bank, in order to obtain information on nutrient availability and recruitment
potential. In addition, the potential vegetation should be assessed through literature, when available, or the
floristic inventory of close areas. As degraded soils generally lack in organic matter and the soil seed bank is poor or
contains undesired ruderal and alien species, external inputs are often necessary. In natural ecosystems, soil amendment
with manure is not to recommend because it may contain foreign seeds. Thus, better options are either litter and
composted vegetation debris collected in close areas, or inert products like biochar. In case the seed bank is not sufficient
for recruiting a ground cover vegetation, artificial seeding should be performed with seeds of species collected in
the surroundings, preferably grass and legume mixtures, because the former reduce erosion and leaching, and the latter
increase soil nitrogen through biological N2-fixation. To foster symbiosis, seeds should be mixed with the soil collected
where legume species were growing. The transplanting of shrubs and finally trees should proceed once an herbaceous
ground cover has established. To spare time and to overcome difficulties in seed collection, the first ground cover could
be obtained also with commercial mixtures of annual species, which should, however, be overthrown before seed production,
thus improving the input of organic matter into the soil, without the risk of introducing foreign seeds.
This pipeline demonstrates that, because of the huge complexity of ecosystems, the conservation of plants within their
natural habitats needs a multidisciplinary approach, and the cooperation with the agricultural sector is essential because
of its deep know-how in the techniques for soil health improvement and plant management. Within this framework,
the SHARIng-Med project (PRIMA foundation) may provide a useful tool to estimate the level of soil degradation
and guide the steps of restoration, as it has the objective of developing a standardized database of soil information for
the Mediterranean area which integrates data on soil and land management with environmental indicators
Numerical simulation of deployable cable nets for the active removal of orbital debris
No full textActive debris removal (ADR) will be part of any future strategy for sustainable space activities in low Earth orbits. The development of effective and adaptable capture devices is one of the main difficulties faced by ADR mission developers, together with the high costs expected. Tethered cable nets are a promising concept for the capture of derelict non-cooperative vehicles, but their modelling, analysis, and design is a non-trivial task. In fact, the net is a kinematically indeterminate, flexible structure undergoing both large displacements and finite strains. Cables have different responses to tensile and compressive forces. The tumbling target constitutes a rheonomic constraint for the net. During the capture phase, multiple unilateral contacts are expected between net and target.
We developed a finite element model for the cable net, adopting the nodal positions as the main unknowns in line with the position-based finite element formulation (PFEF). Large displacements and finite deformations are considered through the Green-Lagrange strain tensor. Cable elements are assumed to react only in tension according to a relaxed hyper-elastic constitutive law. Global damping is introduced into the model according to Rayleigh’s hypothesis. Contact with the target is considered applying the method of Lagrange multipliers and by introducing slack variables to treat the inequality constraint equations. The governing equations for the nonlinear dynamical problem are solved numerically by means of the Newmark method.
The case of a steady obstacle of spherical shape is presented. The proposed approach turns out to be computationally effective to simulate both the deployment of the net and the capture of the debris
Design and Effect of a Resin Infiltration Method to Enhance the Interlayer Adhesion of Additively Manufactured PEEK Parts
No full textThis study investigates post-processing treatments aimed at enhancing the mechanical properties of Polyether Ether Ketone (PEEK) parts fabricated via Fused Filament Fabrication (FFF). FFF-printed PEEK components often exhibit anisotropy and weak interlayer adhesion, which limit their structural performance. To address these issues, a resin infiltration treatment is proposed that yields improvements in flexural strength and strength-to-weight ratio across specimens with different infill percentages. The effectiveness of resin infiltration is compared to that of a thermal post-processing treatment. Experimental results indicate that, although thermal treatment enhances crystallinity, it does not substantially improve interlayer bonding or mitigate anisotropy. In contrast, resin infiltration significantly enhances flexural strength, particularly in specimens with lower infill percentages, by effectively filling pores and reinforcing interlayer adhesion. Overall, the findings demonstrate that vacuum-assisted thermosetting resin infiltration is a promising post-processing technique for improving the mechanical performance of 3D-printed PEEK, achieving a mean flexural strength of up to 34 MPa, approximately 80% higher than that of untreated specimens with 100% infill. Additionally, a cost analysis comparing both post-processing methods is presented, highlighting the cost-effectiveness of resin infiltration as a viable solution to overcome the inherent limitations of FFF-printed PEEK
Precipitation field reconstruction and tracking using opportunistic rain sensors: the Summer 2021 catastrophic event in Germany as a case study
No full textQuantitative precipitation estimates are usually derived based on the measurements collected by
professional instruments, such as weather stations, weather radars, disdrometers, and rain gauges,
with different time/space resolutions, and accuracies.
Recently, the opportunistic use of pre-existing microwave communication links has been investigated
to retrieve precipitation estimates. In particular, satellite-based opportunistic systems for rain
monitoring, are particularly appealing due to: i) the widespread presence of existing DTH satellite
receivers across the territory, which can potentially function as rain-sensing devices, offering significant
geographical coverage, especially in densely populated areas; ii) the ease of installation of new
terminals to obtain higher spatial density; and iii) the low cost of commercial-grade satellite receive
equipment.
In this work, we present a practical application of an opportunistic technique for the estimation of
rainfall intensity. It is based on signal strength measurements made by commercial-grade interactive
satellite terminals. By applying some processing, the rain-induced attenuation on the microwave
downlink from the satellite is first evaluated; then the rain attenuation is mapped into a rainfall rate
estimate via a tropospheric model.
This methodology has been applied to a test area of 30x30 km2 around the city of Dortmund (North
Rhine-Westphalia, upper basin of Ermscher river), for the heavy rain event that devastated Western
Germany in July, 2021.
A spatial and temporal reconstruction of the event was obtained from a set of satellite terminals deployed
in the region, using a classical spatialization method, based on the inverse distance weighting
interpolation. The resulting rainfall maps were successfully compared with those provided by radar
climatology of the Deutscher Wetterdienst (DWD), the national German weather service
What Is the Optimal Sampling Time of Environmental Parameters? Fourier Analysis and Energy Harvesting to Reduce Sensors Consumption in Smart Greenhouses
No full textSmart greenhouses offer crucial solutions for reducing our atmospheric impact and resource waste. However, two fundamental challenges persist in their implementation, massive energy consumption and a high level of human intervention, particularly for sensor battery replacement or recharging. Unfortunately, sensors are indispensable in greenhouses and agriculture, such as for monitoring environmental parameters for air quality assessment. Therefore, while sensors cannot be eliminated, it is essential to optimize their energy consumption. This work introduces an energy-efficient monitoring system for smart greenhouses, aiming to reduce the energy consumption of individual sensors and enhance system sustainability. This study focuses on optimizing the sampling intervals of commonly monitored environmental parameters to minimize sensor energy usage while maintaining data acquisition accuracy adequate for the intended purpose. Additionally, to further reduce battery energy draw, an energy harvesting system using solar panels was implemented. In conclusion, adopting an optimal sampling strategy for each parameter significantly reduces energy consumption compared to fixed, inefficient sampling intervals commonly used in commercial weather stations. Furthermore, by employing an energy harvesting system for each sensor, leveraging the light emitted by greenhouse lamps and external sources ensures the autonomy of sensors within the greenhouse, thereby minimizing the need for human intervention for battery replacement and recharging
Esperienze cliniche con encorafenib e cetuximab in pazienti con carcinoma metastatico del colon-retto con mutazione BRAFV600E dopo recidiva precoce alla chemioterapia adiuvante
No full textMetastatic colorectal cancer (mCRC) is constituted of several biological subgroups characterized by molecular alterations activating specific proliferative pathways. These alterations have, for a long time, lacked targeted therapies capable of inactivating these signalling pathways and eventually modifying the course of the disease. This scenario has rapidly been evolving in recent years, thanks to a better understanding of mCRC biology and advances in drug development, that have turned these alternations into “actionable” targets. BRAFV600E is a landmark example of this process. Conceived for roughly a decade as a negative prognostic factor of outcome and as a predictor of resistance to anti-EGFRs, today it is also a predictor of response to the combination of the anti-BRAF encorafenib and of the anti-EGFR cetuximab, and a standard of care in patients with BRAFV600E-mutated mCRC, after failure of previous systemic therapy. In this work, we report three clinical scenarios where encorafenib and cetuximab are used in label as first-line of treatment, at the diagnosis of mCRC, after early relapse occurring at the end of adjuvant chemotherapy
Improving gender diversity through financial resilience
No full textThis study examines the relationship between gender diversity and financial resilience in a company.
Over the years, the issue of gender diversity in corporate governance has received increasing
attention from both academic and empirical studies. Financial resilience is the ability of a company (entrepreneur and manager) to ‘bounce back’ after adverse events, progressively adapt to not-temporary changes in circumstances, and face environmental stress. This study aims to explain how financial companies are committing to building the pipeline necessary to increase gender diversity. The qualitative approach for collecting information was considered useful in the first step of the research to describe and interpret how a bank can influence financial resilience, which is notably influenced by dominant factors such as income, family size and company size, age, and gender. The research provided a few intriguing results. Specific subjects may influence an individual's capacity for resilience. Laws and corporate rules prevent certain organizations from maintaining diverse practices, such as prohibiting the stereotyping of men and women during the hiring process. In the meantime, these organizations strive to bridge the gender gap by providing both financial and general knowledge and information, such as laws and family policies. Societal differences in gender-based human capital may affect resilience, even though the selection process of financial products does not require stereotyping of men and women. However, there is a positive relationship between information-sharing and problem-solving abilities
in: M.Pisani, Designcafè - Tecniche mimetiche
No full textrecensione del volume Camouflage. Dalla città sotterranea alla città superficial
The clinical significance of artery of Percheron in cerebral ischemia: a summary overview
No full textThe artery of Percheron (AOP) infarction is a rare vascular condition and a pattern of ischemia where a single arterial trunk supplies blood to the rostral midbrain and paramedian thalamic areas, causing neurological deficits. Due to its rarity and atypical presentation, AOP infarction is frequently overlooked in initial assessments, particularly on computed tomography (CT) scans. In addition, different types of AOP infarction have been identified, and it is shown that there can be four significant distinct types of this disease, which may manifest some different symptoms and have various vascular alterations. Knowledge of these variants in the AOP multisystem disorder is imperative to the diagnosis and treatment of infarctions in the condition, hence improving prognosis. To manage this uncommon but important condition, we need to increase awareness among healthcare providers and carry out more research on diagnosis and treatment