A methodology for the evaluation of morphology-based constitutive laws of corroded steel rebars

The assessment of degraded reinforced concrete (RC) existing structures is nowadays a topical problem since several ones have an age close to or higher than their design life. The degradation state of the structure needs to be properly assessed and included in the adopted numerical or analytical models. In this framework, rebars corrosion phenomena can modify the structural behavior of RC members, especially when the corrosive attack is localized in specific areas. As an example, in presence of localized concentrations of chlorides, pitting corrosion of the steel bars occurs, with a localized reduction of the bar section through pits. In this work, the results of a preliminary experimental survey performed on artificially corroded steel rebars are shown, to define an integrated methodology for the definition of material constitutive laws, accounting for morphological aspects of the corrosion phenomenon. A set of steel rebars, embedded in concrete prisms, have been artificially corroded with an accelerated process through electrolytic cells, to obtain local marked pits. The steel rebars have been extracted, cleaned, weighed and subjected to 3D scanning using two different techniques (one based on laser scanning and the other based on structured-light scanning) to evaluate the effective corrosion amount and morphology. Finally, tensile tests were carried out to evaluate the stress-strain curves and the values of yielding, ultimate strengths and elongation to fracture. The presented data and methodology can represent a useful reference for the definition of phenomenological constitutive laws for steel rebars affected by pitting corrosion

SARS-CoV-2 infection predicts larger infarct volume in patients with acute ischemic stroke

Background and purpose: Acute ischemic stroke (AIS) is a fearful complication of Coronavirus Disease-2019 (COVID-19). Aims of this study were to compare clinical/radiological characteristics, endothelial and coagulation dysfunction between acute ischemic stroke (AIS) patients with and without COVID-19 and to investigate if and how the SARS-CoV-2 spike protein (SP) was implicated in triggering platelet activation. Methods: We enrolled AIS patients with COVID-19 within 12 h from onset and compared them with an age- and sex-matched cohort of AIS controls without COVID-19. Neuroimaging studies were performed within 24 h. Blood samples were collected in a subset of 10 patients. Results: Of 39 AIS patients, 22 had COVID-19 and 17 did not. Admission levels of Factor VIII and von Willebrand factor antigen were significantly higher in COVID-19 patients and positively correlated with the infarct volume. In multivariate linear regression analyses, COVID-19 was an independent predictor of infarct volume (B 20.318, Beta 0.576, 95%CI 6.077-34.559; p = 0.011). SP was found in serum of 2 of the 10 examined COVID-19 patients. Platelets from healthy donors showed a similar degree of procoagulant activation induced by COVID-19 and non-COVID-19 patients' sera. The anti-SP and anti-FcγRIIA blocking antibodies had no effect in modulating platelet activity in both groups. Conclusions: SARS-CoV-2 infection seems to play a major role in endothelium activation and infarct volume extension during AIS

Psychological treatments and psychotherapies in the neurorehabilitation of pain. Evidences and recommendations from the italian consensus conference on pain in neurorehabilitation

BACKGROUND: It is increasingly recognized that treating pain is crucial for effective care within neurological rehabilitation in the setting of the neurological rehabilitation. The Italian Consensus Conference on Pain in Neurorehabilitation was constituted with the purpose identifying best practices for us in this context. Along with drug therapies and physical interventions, psychological treatments have been proven to be some of the most valuable tools that can be used within a multidisciplinary approach for fostering a reduction in pain intensity. However, there is a need to elucidate what forms of psychotherapy could be effectively matched with the specific pathologies that are typically addressed by neurorehabilitation teams. OBJECTIVES: To extensively assess the available evidence which supports the use of psychological therapies for pain reduction in neurological diseases. METHODS: A systematic review of the studies evaluating the effect of psychotherapies on pain intensity in neurological disorders was performed through an electronic search using PUBMED, EMBASE, and the Cochrane Database of Systematic Reviews. Based on the level of evidence of the included studies, recommendations were outlined separately for the different conditions. RESULTS: The literature search yielded 2352 results and the final database included 400 articles. The overall strength of the recommendations was medium/low. The different forms of psychological interventions, including Cognitive-Behavioral Therapy, cognitive or behavioral techniques, Mindfulness, hypnosis, Acceptance and Commitment Therapy (ACT), Brief Interpersonal Therapy, virtual reality interventions, various forms of biofeedback and mirror therapy were found to be effective for pain reduction in pathologies such as musculoskeletal pain, fibromyalgia, Complex Regional Pain Syndrome, Central Post-Stroke pain, Phantom Limb Pain, pain secondary to Spinal Cord Injury, multiple sclerosis and other debilitating syndromes, diabetic neuropathy, Medically Unexplained Symptoms, migraine and headache. CONCLUSIONS: Psychological interventions and psychotherapies are safe and effective treatments that can be used within an integrated approach for patients undergoing neurological rehabilitation for pain. The different interventions can be specifically selected depending on the disease being treated. A table of evidence and recommendations from the Italian Consensus Conference on Pain in Neurorehabilitation is also provided in the final part of the pape

What is the role of the placebo effect for pain relief in neurorehabilitation? Clinical implications from the Italian consensus conference on pain in neurorehabilitation

Background: It is increasingly acknowledged that the outcomes of medical treatments are influenced by the context of the clinical encounter through the mechanisms of the placebo effect. The phenomenon of placebo analgesia might be exploited to maximize the efficacy of neurorehabilitation treatments. Since its intensity varies across neurological disorders, the Italian Consensus Conference on Pain in Neurorehabilitation (ICCP) summarized the studies on this field to provide guidance on its use. Methods: A review of the existing reviews and meta-analyses was performed to assess the magnitude of the placebo effect in disorders that may undergo neurorehabilitation treatment. The search was performed on Pubmed using placebo, pain, and the names of neurological disorders as keywords. Methodological quality was assessed using a pre-existing checklist. Data about the magnitude of the placebo effect were extracted from the included reviews and were commented in a narrative form. Results: 11 articles were included in this review. Placebo treatments showed weak effects in central neuropathic pain (pain reduction from 0.44 to 0.66 on a 0-10 scale) and moderate effects in postherpetic neuralgia (1.16), in diabetic peripheral neuropathy (1.45), and in pain associated to HIV (1.82). Moderate effects were also found on pain due to fibromyalgia and migraine; only weak short-term effects were found in complex regional pain syndrome. Confounding variables might have influenced these results. Clinical implications: These estimates should be interpreted with caution, but underscore that the placebo effect can be exploited in neurorehabilitation programs. It is not necessary to conceal its use from the patient. Knowledge of placebo mechanisms can be used to shape the doctor-patient relationship, to reduce the use of analgesic drugs and to train the patient to become an active agent of the therapy

Vulnerability assessment methods for rocking and overturning of free standing elements

This paper presents a comparison between different methods for assessing the probability of rocking and overturning of free standing elements, under the action of ground motions of given intensities. The classical Ishiyama criterion is considered and compared with both kinematic linear and non linear analyses recommended by the Italian Standard (i.e. KL and KNL respectively) and with the displacement based approach proposed by Lam-Gad. The main differences among these methods are highlighted and validated on the basis of experimental tests available in literature, by using real seismic records. Then, the different stability criteria are used to obtain overturning stability charts, based on conventional spectra assumed by Eurocode 8 and some considerations concerning the applicability conditions of each method are given

Comparing outcomes of ‘voluntary’ and ‘quasi-compulsory’ treatment of substance dependence in Europe

Aim: This study evaluates quasi-compulsory drug treatment (QCT) arrangements for substance-dependent offenders receiving treatment instead of imprisonment in comparison to voluntary treatment within five European countries. Methods: Participants were interviewed with the European Addiction Severity Index, the ASI-crime module, questions on perception of pressure and self-efficacy, and the Readinessto- Change Questionnaire at treatment entry and after 6, 12, and 18 months. Results: Reductions in substance use and crime as well as improvements in health and social integration were observed in QCT and voluntary treatment groups. After controlling for various factors, subjects in the QCT and the comparison group showed similar reductions in substance use and crime over time. Study retention was comparable in both groups. Conclusion: QCT is as effective as voluntary treatment provided in the same services in reducing substance use and crime

Rocking activation of free standing elements in real conditions: A safe experimentally-based acceleration limit

This paper presents an experimental campaign aimed to characterize rocking conditions of free-standing elements. Focus is given on the minimum horizontal acceleration required to activate rocking. The proposed experimental campaign mainly regards prismatic samples, that differ in size R (ranging from 6.30 cm to 23.0 cm), aspect ratio B/H (mostly 0.20 and 0.33) and material (wood, marble, steel). Small scale specimens are tested since no scale effect is expected in the rocking activation phenomenon. Both harmonic (continuous and pulse) and seismic input signals are applied for a total of more than three hundred tests. Experimental results evidence that, in most cases, rocking occurs for acceleration lower than the value generally assumed as the rocking limit, which is proportional, by acceleration gravity, to the aspect ratio. Therefore, a different value is proposed for the acceleration that triggers rocking phenomenon, with the aim of defining a safe acceleration threshold usable in vulnerability assessment of free standing elements. Actually, this limit takes into account the real conditions of rocking behavior, e.g. element imperfections, not perfectly rigid conditions for both block and supporting floor, not planarity of the contact surfaces

Vulnerability assessment and seismic mitigation intervention for artistic assets : from theory to practice

This paper deals with the vulnerability assessment of artistic assets, aiming at exploiting the potential of specifically designed seismic-isolation strategy to mitigate their seismic risk. In detail, starting from a review of the multidisciplinary procedure proposed by some of the authors for evaluating the safety level of art objects, this paper focuses on the required steps necessary to effectively design proper seismic mitigation intervention. For this purpose, the case study of the bust of Francesco I d'Este is investigated. This sculpture is housed at the second floor of Palazzo dei Musei in Modena, one of the cities hit by the seismic events occurred in May 2012 in Italy, which brought up to date the need of preserving this valuable object from seismic risk. After a preliminary vulnerability analysis carried out to assess the safety of the bust, a specific intervention of seismic isolation is conceived and realized by adopting Double Concave Curved Surface Sliders (DCCSS), which combine a strong flexibility to different museum contexts, with the possibility of standardizing the production process. To this aim, some operative charts are proposed as useful tool for the design phase of the seismic devices. Then special attention is devoted to an accurate evaluation of the seismic action, considering the location of the artistic asset at upper floors, also by means of different strategies for numerical modeling of the host masonry building. Finally, a series of non linear dynamic analyses are carried out to assess the effectiveness of the whole isolated syste

Structural response of corroded RC beams: a comprehensive damage approach

In this work, a comprehensive approach to model the structural behaviour of Reinforced Concrete (RC) beams subjected to reinforcement corrosion is proposed. The coupled environmental – mechanical damage model developed by some of the authors is enhanced for considering the main effects of corrosion on concrete, on composite interaction between reinforcement bars and concrete and on steel reinforcement. This approach is adopted for reproducing a set of experimental tests on RC beams with different corrosion degrees. After the simulation of the sound beams, the main parameters involved in the relationships characterizing the effects of corrosion are calibrated and tested, referring to one degraded beam. Then, in order to validate the proposed approach and to assess its ability to predict the structural response of deteriorated elements, several corroded beams are analyzed. The numerical results show a good agreement with the experimental ones: in particular, the proposed model properly predicts the structural response in terms of both failure mode and load-deflection curves, with increasing corrosion level

Valutazioni preliminari su base sperimentale per un criterio di stabilit\ue0 di oggetti appoggiati

In questo lavoro vengono presentati alcuni risultati di una campagna di prove sperimentali eseguita su una serie di campioni, diversi per forma e materiale, semplicemente appoggiati e sollecitati da forzanti armoniche e da segnalisismici. Vengono discussi i limiti usualmente assunti per la definizione dei criteri di oscillazione e ribaltamentoottenuti in base all\u2019ipotesi di corpo rigido. Sulla base dei risultati delle prove, vengono proposte alcune valutazioni preliminari per la definizione diun criterio di stabilit\ue0che tenga conto della presenza di imperfezioni dei campioni, utilizzabile per la valutazione di sicurezza di elementi non strutturali reali, in condizioni di semplice appoggio, quali sono la maggior parte degli elementi che appartengono alla categoria\u201cbeni contenuti negli edifici\u201d