Immersive VR for upper-extremity rehabilitation in patients with neurological disorders: a scoping review

Background: Neurological disorders, such as stroke and chronic pain syndromes, profoundly impact independence and quality of life, especially when affecting upper extremity (UE) function. While conventional physical therapy has shown effectiveness in providing some neural recovery in affected individuals, there remains a need for improved interventions. Virtual reality (VR) has emerged as a promising technology-based approach for neurorehabilitation to make the patient’s experience more enjoyable. Among VR-based rehabilitation paradigms, those based on fully immersive systems with headsets have gained significant attention due to their potential to enhance patient’s engagement. Methods: This scoping review aims to investigate the current state of research on the use of immersive VR for UE rehabilitation in individuals with neurological diseases, highlighting benefits and limitations. We identified thirteen relevant studies through comprehensive searches in Scopus, PubMed, and IEEE Xplore databases. Eligible studies incorporated immersive VR for UE rehabilitation in patients with neurological disorders and evaluated participants’ neurological and motor functions before and after the intervention using clinical assessments. Results: Most of the included studies reported improvements in the participants rehabilitation outcomes, suggesting that immersive VR represents a valuable tool for UE rehabilitation in individuals with neurological disorders. In addition, immersive VR-based interventions hold the potential for personalized and intensive training within a telerehabilitation framework. However, further studies with better design are needed for true comparison with traditional therapy. Also, the potential side effects associated with VR head-mounted displays, such as dizziness and nausea, warrant careful consideration in the development and implementation of VR-based rehabilitation programs. Conclusion: This review provides valuable insights into the application of immersive VR in UE rehabilitation, offering the foundation for future research and clinical practice. By leveraging immersive VR’s potential, researchers and rehabilitation specialists can design more tailored and patient-centric rehabilitation strategies, ultimately improving the functional outcome and enhancing the quality of life of individuals with neurological diseases

Dynamic behaviour and seismic response of structures isolated with low shape factor bearings

This study investigates the mechanical behaviour of laminated elastomeric bearings with a low shape factor (LSF) and the dynamic response of structures mounted on them. Axial loads have a significant influence on the mechanical behaviour of the LSF bearings. Most of the existing theories and mechanical models for laminated bearings cannot be employed for LSF bearings because they disregard the important effects of axial shortening and bulging of the rubber layers on the horizontal bearing stiffness. In this study, a simplified model originally developed for slender rubber blocks is employed for describing the mechanical behaviour of LSF bearings, and validated against the experimental results on low-damping LSF bearings manufactured and tested at Tun Abdul Razak Research Center (TARRC). The proposed model is then used to simulate the seismic response of a structural prototype mounted on the low-damping LSF bearings and tested at University of Naples Federico II on a shaking table under horizontal seismic input. Further analyses are carried out to evaluate how the bearing shape factor affects the dynamic and seismic response of the prototype. The study provides some useful insight into the complex mechanical behaviour of LSF bearings and of structures mounted on them

Clinical Outcomes of Patients With Metastatic Urothelial Carcinoma After Progression to Immune Checkpoint Inhibitors: A Retrospective Analysis by the Meet-Uro Group (Meet-URO 1 Study)

Background: Immune checkpoint inhibitors (ICIs) are currently the standard of care for metastatic urothelial cancer (mUC) after the failure of previous platinum-based chemotherapy. The choice of further therapy after ICI progression is a new challenge, and scarce data support it. We aimed to examine the outcomes of mUC patients after progression to ICI, especially when receiving chemotherapy. Methods: Data were retrospectively collected from clinical records of mUC patients whose disease progressed to anti-programmed death 1 (PD-1)or programmed death ligand 1 (PD-L1) therapy at 14 Italian centers. Patients were grouped according to ICI therapy setting into SALVAGE (ie, ICI delivered ⩾ second-line therapy after platinum-based chemotherapy) and NAÏVE (ie, first-line therapy) groups. Progression-free survival (PFS) and overall survival (OS) rates were calculated using the Kaplan-Meier method and compared among subgroups. Cox regression assessed the effect of treatments after progression to ICI on OS. Objective response rate (ORR) was calculated as the sum of partial and complete radiologic responses. Results: The study population consisted of 201 mUC patients who progressed after ICI: 59 in the NAÏVE cohort and 142 in the SALVAGE cohort. Overall, 52 patients received chemotherapy after ICI progression (25.9%), 20 (9.9%) received ICI beyond progression, 115 (57.2%) received best supportive care only, and 14 (7.0%) received investigational drugs. Objective response rate to chemotherapy in the post-ICI setting was 23.1% (28.0% in the NAÏVE group and 18.5% in the SALVAGE group). Median PFS and OS to chemotherapy after ICI-PD was 5 months (95% confidence interval [CI]: 3-11) and 13 months (95% CI: 7-NA) for the NAÏVE group; 3 months (95% CI: 2-NA) and 9 months (95% CI: 6-NA) for the SALVAGE group, respectively. Overall survival from ICI initiation was 17 months for patients receiving chemotherapy (hazard ratio [HR] = 0.09, p < 0.001), versus 8 months for patients receiving ICI beyond progression (HR = 0.13, p < 0.001), and 2 months for patients who did not receive further active treatment (p < 0.001). Conclusions: Chemotherapy administered after ICI progression for mUC patients is advisable irrespective of the treatment line

A focus on the new italian guidelines for safety assessment of existing bridges (Key-note lecture)

New Italian guidelines for safety assessment of existing bridges were recently approved. This achievement was reached after the increasing number of casualites which clearly demonstrated the need for an in deep consideration of existing bridges. Actually, most of italian bridges already spent around 50 years of their service life and may require extraordinary repairs to achieve satisfactory safety levels according to latest code provisions. The guidelines represent an unprecedented document in the international context: they provide with additional analysis cases with different traffic loads and partial safety factors to be adopted in order to establish the bridge safety class at ultimate limit state. After introducing the main scope of the work, a preliminary case-study bridge with relative outcomes is proposed

Fragility analysis of existing prestressed concrete bridges under traffic loads according to new Italian guidelines

After the 2018 collapse of Morandi highway bridge in Genova, new Italian guidelines (GL) were issued for prioritization of safety evaluations and retrofit interventions on existing bridges. Among several novelties, GL introduced new traffic load models (TLMs) which can be adopted for existing bridges in case of noncompliant safety checks according to the Italian building code (NTC) provisions. In this study, a class of simply supported, beam-type, prestressed concrete bridge decks built between 1970 and 1980 in Italy is considered. Assuming geometric, material, and load random variables together with consideration of capacity model uncertainty, Monte Carlo sampling technique was implemented in MATLAB in order to randomly generate deck models and to evaluate their traffic-load fragility. Fragility analysis was carried out to compare vulnerability levels of existing Italian bridges under different load patterns provided by GL and NTC. In addition to a prescribed TLM, the sensitivity of fragility to bridge usage limitations, such as reduced distance of external load lane from kerb or reduced number of lanes, was also quantified to support decision-making by road management companies. In the final part of the study, the annual failure probability of selected bridges was estimated using a European weigh-in-motion database and convolution of fragility and hazard. Analysis results show that structural fragility significantly depends on the load pattern, indicating that more realistic vehicle models should be developed to achieve a target safety level conforming to modern codes for constructions

Numerical investigation of rubber bearings with low shape factor under seismic excitation

This study illustrates the development of a modeling strategy for simulating the seismic response of structures mounted on elastomeric bearings with a low shape factor (LSF). These bearings can be employed to achieve a three-dimensional seismic isolation of structures, due to their low vertical and horizontal stiffness. The first part of this work investigates the mechanical behaviour of LSF bearings by means of three-dimensional Finite Element (FE) analysis in Abaqus. The FE results provide a numerical evaluation of the horizontal, vertical, and rotational stiffness of the bearings. These are used in the second part of the study to develop in SAP2000 a simplified model of a structure with LSF bearings tested experimentally on the shaking table at University of Naples Federico II. The study results show that the developed model can be effectively used to simulate the response of the isolated structure under different earthquake inputs

Traffic-load fragility models for prestressed concrete girder decks of existing Italian highway bridges

Even if previous studies investigated seismic fragility of existing bridges, some recent collapse cases set the need to investigate their vulnerability under gravity loads. In this study, the class of simply supported, beam-type, prestressed concrete bridges built between 1970 and 1980 was considered to carry out a fragility analysis of the most recurrent type of Italian bridges to traffic loads. Based on the literature and new data collected by the authors from real bridges, geometric, material and load variables were defined through probability distributions and regression models. Then, a code-based capacity modelling of bridge decks was carried out, followed by the implementation of a simplified deck analysis method that allows extensive simulations. In a first step, a sensitivity analysis was performed to identify the random variables that mostly affect the structural response, to be taken into account in the fragility analysis for the ultimate limit state. Then, a fragility analysis was carried through a fully automatic procedure implemented in MATLAB. The main output consists of fragility models that might be used by engineers, roadway management companies and decision-makers in large-scale risk assessments of existing highway bridges under code-based traffic loads, as a basis for prioritization of more refined performance evaluations and structural retrofitting programmes

Experimental testing of full-scale fiber reinforced elastomeric isolators (FREIs) in unbounded configuration

Fiber reinforced elastomeric isolators (FREIs) have shown to be a promising option as an alternative to classical steel reinforced elastomeric isolators (SREIs). Previous investigations were limited to scaled-geometries without any attempt to test such devices under code-compliant protocols as per international standards. In the present study the authors investigated two circular full-scale (diameter 620 mm) FREIs manufactured with a non-standard process adopting a soft rubber compound and polyester fibers. Experimental tests were performed in unbounded configuration through the large anti-seismic device test facility at the EUROLAB of the University of Messina, Italy. A significant number of protocols were imposed to the prototypes in order to demonstrate the effect of different loading conditions, i.e., strain level, frequency of the excitation, axial load and repeated loading. The tests confirmed the significant dependency of mechanical behavior on axial load which tends to increase damping (i.e., higher friction mechanisms) while reducing stiffness (i.e., lower stability limits). Due to internal slippage at the fiber-rubber layers interface, damping capacity of FREIs achieved 20% of critical, i.e., significantly higher than that commonly achieved in SREIs with the same rubber compound. Even if adequate capacity was reached in compression, the run-in effect would limit the axial stiffness of FREIs. A significant roll-over phenomenon was detected under lateral loading up to a maximum shear strain of 100% without damage and permanent deformation after unloading. A numerical study finally demonstrated the effectiveness of FREIs when compared to SREIs in a base isolation system designed for a 3-storey reinforced concrete frame located in a high seismicity region in Italy. Lower axial stiffness of FREIs did not affect the seismic performance of the building due to limited rocking motion component and beneficial higher damping mechanism. This paper provides a significant contribution to the standardization of FREIs to be adopted in base isolation of conventional buildings

Fragility of existing Italian bridges to traffic loads

Fragility curves are a well-established tool to define probabilistically the vulnerability of an asset to a prescribed hazard. The majority of previous studies have investigated the seismic fragility of structures and infrastructures. Nonetheless, recent disasters have highlighted the need to assess the vulnerability of aging bridges to gravity loads. Based on existing data from the literature and novel data from some real case studies, the present work presents analytical fragility curves of Italian bridges to traffic loads. The class of simply supported, beam-type, prestressed concrete bridges constructed between 1960 and 1980 was considered, given that those structures are the most recurrent type of existing Italian bridges. Then, a fragility analysis was performed through a fully automated procedure implemented in MATLAB. Geometric, material and load parameters were defined as random variables considering their probability distribution and correlation through either univariate or multivariate models. Structural fragility was evaluated with respect to the limit state of collapse. The output of this study can be of interest to engineers and decisions makers who must manage existing bridges, considering their probability of collapse under traffic loads and eventually limiting their use before structural retrofitting

Experimental behavior of full-scale unbounded polyester-fiber reinforced rubber isolators for residential buildings

This paper presents the results of an investigation on full-scale innovative low-cost unbounded polyester-fiber reinforced high-damping elastomeric isolators (UPFREIs) to be used for seismic protection of residential buildings in Colombia, South America. In order to characterize the mechanical behavior of the UPFREIs, two full-scale prototypes were manufactured and tested at the Structures Laboratory of the Universidad del Valle. The experimental results were compared with results from the same test performed with two traditional connected steel reinforced isolators (SREIs). Both isolation systems were designed for a residential 5-story building with a target period of 2,5s located in a medium-high seismicity region. A dedicated set-up was designed and built specifically for the experimental tests. Results from shear tests up to 100% shear strain with sustained axial load exhibited very satisfactory behavior of the UPFREIs versus the SREIs with no residual deformation after unloading. An enhanced damping mechanism with damping ratio between 10 and 15 % was provided by the frictional fiber interface. Lower horizontal stiffness of the UPFREIs was obtained at higher deformation levels due to the typical rollover deformation. Despite the higher axial flexibility with respect to SREIs, UPFREIs also provided an adequate vertical to horizontal stiffness ratio. The results show that the developed UPFREIs have great potential to be implemented as a low-cost seismic isolation system of residential buildings