Taking inspiration from a recent book by Marcello Verga, the present paper reaffirms the scientific status of genealogy and focuses on the importance of this autonomous subject, fundamental in ...carrying out correct research in many fields. The paper also underlines the crucial role played by all historical documentary sciences (once equivocally called ‘Auxiliary sciences of History’) and the reasons why their enhancement and development remains essential, especially in the academic world.
Dairy cows face several challenges during the transition period, and the administration of live yeast might be useful to mitigate this stressful condition. In the current study, the effects of live ...yeast administration on milk production, feed intake, and metabolic and inflammatory conditions were evaluated. Multiparous Holstein cows were enrolled in this randomized controlled trial and received either a control diet (CTR,
= 14) or the control diet plus 4 g/d of live
yeast (LSC,
= 14) from -21 to 56 days relative to calving. Dry matter intake, milk yield and composition, and rumination time were monitored daily. Blood samples were collected at -21, -7, 3, 14, 28, 42, and 56 days relative to calving to evaluate the metabolic profile. Fecal samples were collected at 56 days relative to calving to measure volatile fatty acids and feed digestibility. No differences between groups were observed in dry matter intake. Compared with CTR, rumination time was lower in LSC in after calving. Although there were no differences in milk components between groups, LSC had greater milk yield in the last three weeks of the study than CTR. No differences were observed in inflammatory markers or other plasma metabolites, except for β-hydroxybutyrate, which was higher in LSC, and reactive oxygen metabolites (ROMs), which were lower in LSC. Overall, these outcomes suggest that live yeast supplementation had some positive effects on milk yield and oxidative status.
In sub-Saharan Africa (SSA), stroke incidence is ~316 cases per 100,000 inhabitants and in 75% of SSA countries stroke is among the top three causes of death. This epidemiological evolution results ...from the exponential growth of the African population as well as the lack of policies for prevention and therapy. The Democratic Republic of Congo is one of the countries included as a “low-income country” in the 2023 Organization for Economic Co-operation and Development's Development Assistance Committee List; its capital, Kinshasa, is a megalopolis with more than 18 million inhabitants. According to our knowledge, no hospital in Kinshasa is currently capable of admitting and treating patients with stroke according to international guidelines. The Italian Stroke Association—Associazione Italiana Ictus (ISA-AII) is a multidisciplinary scientific society for the fight against cerebrovascular diseases. Some members of the ISA-AII joined to form a working group dedicated to the care of stroke in Africa. In this article, we explain the project designed by ISA Africa that, in collaboration with the referral hospital of a district of Kinshasa, has the aim of building a network for diagnosing and treating stroke, including ambulance services, a stroke team in the emergency room, a stroke unit, an outpatient clinic, and primary prevention activities among the population.
Structural health monitoring of civil infrastructure, such as bridges and buildings, has become a trending topic in the last few years. The key factor is the technological push given by new ...technologies that permit the acquisition, storage, processing and visualisation of data in real time, thus assessing a structure’s health condition. However, data related to anomaly conditions are difficult to retrieve, and, by the time those conditions are met, in general, it is too late. For this reason, the problem becomes unsupervised, since no labelled data are available, and anomaly detection algorithms are usually adopted in this context. This research proposes a novel algorithm that transforms the intrinsically unsupervised problem into a supervised one for condition monitoring purposes. Considering a bridge equipped with N sensors, which measure static structural quantities (rotations of the piers) and environmental parameters, exploiting the relationships between different physical variables and determining how these relationships change over time can indicate the bridge’s health status. In particular, this algorithm involves the training of N models, each of them able to estimate the quantity measured via a sensor by using the others’ N−1 measurements. Hence, the system can be represented by the ensemble of the N models. In this way, for each sensor, it is possible to compare the real measurement with the predicted one and evaluate the residual between the two; this difference can be addressed as a symptom of changes in the structure with respect to the condition regarded as nominal. This approach is applied to a real test case, i.e., Candia Bridge in Italy, and it is compared with a state-of-the-art anomaly detector (namely an autoencoder) in order to validate its robustness.
The present study deals with the structural safety evaluation of a 50-year-old river bridge, called Baghetto Bridge, located in north Italy on the Adda River. Generally speaking, hydraulic processes ...are the main cause of bridge failure. Scour and hydrodynamic loads have been largely studied by the hydraulic engineering community; however, in practice, integration with structural analysis is often missing. The aim of this research is to provide a multidisciplinary procedure based on hydraulic and dynamic investigations devoted to the structural verification and monitoring of river bridges with traditional mechanical bearings. The deck–river interaction is addressed, studying the influence of debris accumulation on the bridge and performing structural verification of the bearing supports. The actions exerted on the bridge deck by the river current were estimated following the recommendations of the Italian code and making some further assumptions. In addition, dynamic investigations and FE modelling were performed. The results show (1) a relatively fast procedure that can be applied by practitioners to perform structural verification of river bridges with traditional mechanical bearings, and (2) an investigation method to evaluate temperature–frequency correlation as a reference for future inspections.
This article addresses the problem of the position of equity holders in restructuring proceedings, tackling a new issue in the overall European scenario of insolvency law, where innovative rules have ...been introduced on this topic in Germany (ESUG), France (loi Macron), Spain (ley concursal), besides the new provisions laid down by the EU Preventive Restructuring Directive. Overall, these rules target the same outcome, while relying on different tools, namely, to overcome the veto power of shareholders in the enforcement of an approved and confirmed restructuring plan. Shareholders can in fact resort to their veto power pursuant to company law when dealing with structural operations having an impact on the property structure of a distressed company, that is, a debt‐equity‐swap. This article focuses on the rules governing the position of shareholders as laid down in Article 163, paragraph 5 and Article 185, paragraph 6 of the Italian Insolvency Law (IIL), in force since 2015, which will be probably amended in September 2021 by Articles 90 and 118 of the new Italian Crisis and Insolvency Code (ICC). The article ultimately provides a comparison with the legal framework in other European countries as well as in the EU Preventive Restructuring Directive. Many issues arise from the new Italian regulation, in particular regarding its field of application, its relationship and its coordination with company law and the protection of shareholders' property in the shares.
This paper presents the application of a stabilized mixed strain/displacement finite element formulation for the solution of nonlinear solid mechanics problems involving compressible and ...incompressible plasticity. The variational multiscale stabilization introduced allows the use of equal order interpolations in a consistent way. Such formulation presents two advantages when compared to the standard, displacement based, irreducible formulation: (a) it provides enhanced rate of convergence for the strain (and stress) field and (b) it is able to deal with incompressible situations. The first advantage also applies to the comparison with the mixed pressure/displacement formulation. The paper investigates the effect of the improved strain and stress fields in problems involving strain softening and localization leading to failure, using low order finite elements with continuous strain and displacement fields (P1P1 triangles or tetrahedra and Q1Q1 quadrilaterals, hexahedra, and triangular prisms) in conjunction with an associative frictional Drucker–Prager plastic model. The performance of the strain/displacement formulation under compressible and nearly incompressible deformation patterns is assessed and compared to a previously proposed pressure/displacement formulation. Benchmark numerical examples show the capacity of the mixed formulation to predict correctly failure mechanisms with localized patterns of strain, virtually free from any dependence of the mesh directional bias. No auxiliary crack tracking technique is necessary.
Bridges and viaducts are facing growing traffic, increasing loads as well as ageing and deterioration. Nowadays, vibration‐based Structural Health Monitoring (SHM) represents an effective solution to ...extract quantitative information regarding bridge structural condition. Bridge frequencies are fundamental parameters capable to reflect and summarize bridge dynamics and health condition. Typically, their identification is performed by direct approaches, which rely on the use of sensors installed on the structure under analysis. A cost‐efficient, movable, and flexible alternative is offered by drive‐by methods, consisting in the use of instrumented vehicles to extract bridge frequencies. This paper presents an experimental campaign carried out on a multiple‐span mixed railroad bridge, with the aim to identify its frequencies through onboard measurements. A set of MEMS wireless accelerometers is deployed on the vehicle, firstly allowing for vehicle pitch component mitigation. Vehicle accelerations were then used to extract bridge frequencies, by means of a Most Probable Modal Frequencies approach, relying on synchrosqueezed wavelet transform. At a cruise speed of 30 km/h promising results in terms of indirect frequency estimation were found, with no traffic disruption.
•Mixed FEM is applied to mode III and mixed mode failure in quasi-brittle materials.•A mixed strain displacement formulation is used in plasticity and continuum damage.•The material behavior is ...described via Rankine and Drucker-Prager failure criteria.•Exploiting compatibility conditions it is possible to reduce the computational time.•Numerical results show good agreement with experiments on skew-notched beams.
The testing of mode III and mixed mode failure is every so often encountered in the dedicated literature of mechanical characterization of brittle and quasi-brittle materials. In this work, the application of the mixed strain displacement ε-u finite element formulation to three examples involving skew notched beams is presented. The use of this FE technology is effective in problems involving localization of strains in softening materials.
The objectives of the paper are: (i) to test the mixed formulation in mode III and mixed mode failure and (ii) to present an enhancement in terms of computational time given by the kinematic compatibility between irreducible displacement-based and the mixed strain-displacement elements.
Three tests of skew-notched beams are presented: firstly, a three point bending test of a PolyMethyl MethaAcrylate beam; secondly, a torsion test of a plain concrete prismatic beam with square base; finally, a torsion test of a cylindrical beam made of plain concrete as well. To describe the mechanical behavior of the material in the inelastic range, Rankine and Drucker-Prager failure criteria are used in both plasticity and isotropic continuum damage formats.
The proposed mixed formulation is capable of yielding results close to the experimental ones in terms of fracture surface, peak load and global loss of carrying capability. In addition, the symmetric secant formulation and the compatibility condition between the standard irreducible method and the strain-displacement one is exploited, resulting in a significant speedup of the computational procedure.
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