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This study presents the development and rigorous evaluation of a Fiber Bragg Grating (FBG)-based Outside Air Temperature (OAT) sensor designed for aircraft applications. Employing a Design of Experiments (DoE) approach, the research optimized the sensor's performance for reliability, accuracy, and durability in aviation environments. Experimental assessment covered detailed installation of the FBG sensor on an aircraft, considering influential parameters such as outside dimensions and varying temperature. The OAT sensor's design focused on robustness and precision for accurate real-time temperature recording, vital for operational efficiency and safety. Extensive statistical analysis assessed the sensor's performance under differing conditions, providing valuable insights into operational capabilities and overall efficacy. Thermo-climatic chamber tests simulated extreme environmental conditions to validate the sensor's durability and function under potential aircraft operational scenarios. This research enhances understanding of FBG-based OAT sensors for aircraft applications, demonstrating their superior robustness and performance capabilities, thereby contributing to aviation safety, operational efficiency, and data precision.© 2017 Elsevier Inc. All rights reserved. more...

OBJECTIVES: Cytomegalovirus (CMV) infection represents a serious post-transplantation complication, particularly among transplant recipients with resistant or refractory (R/R) infection. Despite the improvement made in CMV prevention and treatment, remains a need for new therapies that are better tolerated and safer for patients, especially for refractory or resistant (R/R) infections. This analysis investigates the cost-effectiveness of maribavir versus investigator-assigned therapy (IAT) for treatment of post-transplant R/R CMV in the Italian context. METHODS: The analysis was conducted from the National Health Service (NHS) perspective using a Markov model previously developed in Excel® to evaluate the cost-effectiveness of maribavir versus IAT for the treatment of post-transplant R/R CMV. Health event rates and transition probabilities were informed by data from observational studies and from SOLSTICE clinical trial, which compared maribavir to conventional antiviral treatments for transplant patients with R/R CMV infections. Utilities were from SOLSTICE and a utility vignette study. Costs inputs were derived from published literature and Italian national tariffs for outpatient and hospital services. Costs and outcomes were discounted by 3%. RESULTS: Maribavir compared to the IAT used for the treatment of post-transplant R/R CMV achieved an incremental cost of € 11,455 for an incremental quality adjusted life year (QALY) gain of 0.313. This resulted in an incremental cost-effectiveness ratio of € 36,626/QALY, for maribavir compared to IAT, which is below the generally accepted, national willingness-to-pay threshold for orphan drugs (€ 37,000/QALY). CONCLUSIONS: This analysis showed that maribavir, an orphan drug treatment, is cost-effective compared to the current antiviral treatments used for treatment of post-transplant R/R CMV. more...

Purpose: Motor outputs are governed by dynamics organized around stable states and spontaneous transitions: we seek to investigate the swimmers' motor behavior flexibility as a function of speed and aquatic environment manipulations. Method: Eight elite male swimmers partook an eight-level incremental test (4% increment from 76% to 104% of their mean speed on 200 m front crawl) in a quasi-static aquatic environment (pool). Swimmers then partook another incremental test at similar effort in a dynamic aquatic environment (swimming flume) up to maximal speed. Stroke rate (SR), index of coordination (IdC) and intersegmental coupling of the upper limbs were computed from the inertial sensors located on the upper limbs and the sacrum. Results: With speed increase, SR values presented a steeper linear increase in the pool than in the flume. IdC values increased also in the pool but remained stable in the flume. Individual SR and IdC vs. speed increase displayed second-order polynomial dynamics, indicative of adaptive flexibility with a range of extremum values more restricted in the flume. Finally, a reduction of the in-phase coordination pattern was noted with flume speed increase. Conclusions: Action possibilities were strongly constrained in the flume at the highest speeds as the fluid flow led to discontinuity in the propulsive actions of the upper limbs and lack of in-phase inter-segmental coordination. This highlights that the behavioral flexibility was restricted in the flume in comparison to the pool, in which the exploitation of opportunities for action involved a larger number of degrees of freedom in the movement. more...

The utilization of Fiber Bragg Grating (FBG) sensors in innovative optical sensor networks has displayed remarkable potential in providing precise and dependable thermal measurements in hostile environments on Earth. Multi-Layer Insulation (MLI) blankets serve as critical components of spacecraft and are employed to regulate the temperature of sensitive components by reflecting or absorbing thermal radiation. To enable accurate and continuous monitoring of temperature along the length of the insulative barrier without compromising its flexibility and low weight, FBG sensors can be embedded within the thermal blanket, thereby enabling distributed temperature sensing. This capability can aid in optimizing the thermal regulation of the spacecraft and ensuring the reliable and safe operation of vital components. Furthermore, FBG sensors offer sev eral advantages over traditional temperature sensors, including high sensitivity, immunity to electromagnetic interference, and the ability to operate in harsh environments. These properties make FBG sensors an excellent option for thermal blankets in space applications, where precise temperature regulation is crucial for mission success. Nevertheless, the calibration of temperature sensors in vacuum conditions poses a significant challenge due to the lack of an appropriate calibration reference. Therefore, this paper aimed to investigate innovative solutions for calibrating temperature sensors in vacuum conditions. The proposed solutions have the potential to enhance the accuracy and reliability of temperature measurements in space applications, which can enable engineers to develop more resilient and dependable spacecraft systems. more...

The deployment of electro-mechanical actuators plays an important role towards the adoption of the more electric aircraft (MEA) philosophy. On the other hand, a seamless substitution of EMAs, in place of more traditional hydraulic solutions, is still set back, due to the shortage of real-life and reliability data regarding their failure modes. One way to work around this problem is providing a capillary EMA prognostics and health management (PHM) system capable of recognizing failures before they actually undermine the ability of the safety-critical system to perform its functions. The aim of this work is the development of a model-based prognostic framework for PMSM-based EMAs leveraging a metaheuristic algorithm: the evolutionary (differential evolution (DE)) and swarm intelligence (particle swarm (PSO), grey wolf (GWO)) methods are considered. Several failures (dry friction, backlash, short circuit, eccentricity, and proportional gain) are simulated by a reference model, and then detected and identified by the envisioned prognostic method, which employs a low fidelity monitoring model. The paper findings are analysed, showing good results and proving that this strategy could be executed and integrated in more complex routines, supporting EMAs adoption, with positive impacts on system safety and reliability in the aerospace and industrial field. more...

Adoption of electromechanical actuation systems in aerospace is increasing, and so reliable diagnostic and prognostics schemes are required to ensure safe operations, especially in key, safety-critical systems such as primary flight controls. Furthermore, the use of prognostics methods can increase the system availability during the life cycle and thus reduce costs if implemented in a predictive maintenance framework. In this work, an improvement of an already presented algorithm will be introduced, whose scope is to predict the actual degradation state of a motor in an electromechanical actuator, also providing a temperature estimation. This objective is achieved by using a properly processed back-electromotive force signal and a simple feed-forward neural network. Good prediction of the motor health status is achieved with a small degree of inaccuracy. more...

The endocannabinoid system is involved in the nociceptive and anti-inflammatory pathways, and a lowered expression of CB2 receptors has been associated with inflammatory conditions, such as osteoarthritis (OA). This suggests that CB2 modulators could be novel therapeutic tools to treat OA. In the present study, the involvement of Harpagophytum procumbens root extract, a common ingredient of nutraceuticals used to treat joint disorders, in CB2 modulation has been evaluated. Moreover, to clarify the effects of the pure single components, the bioactive constituent, harpagoside, and the main volatile compounds were studied alone or in a reconstituted mixture. Human fibroblast-like synoviocytes, extracted by joints of patients, who underwent a total knee replacement, were treated with an H. procumbens root extract dissolved in DMSO (HPEDMSO). The effectiveness of HPEDMSO to affect CB2 pathways was studied by analyzing the modulation of cAMP, the activation of PKA and ERK MAP kinase, and the modulation of MMP-13 production. HPEDMSO was able to inhibit the cAMP production and MAP kinase activation and to down-regulate the MMP-13 production. Pure compounds were less effective than the whole phytocomplex, thus suggesting the involvement of synergistic interactions. Present findings encourage further mechanistic studies and support the scientific basis of the use of H. procumbens in joint disorders. more...

Abstract Several studies have suggested a possible relationship between polymorphic variants of the taste receptors genes and the acceptance, liking and intake of food and beverages. In the last decade investigators have attempted to link the individual ability to taste 6-n-propylthiouracil (PROP) and the sensations, such as astringency and bitterness, elicited by wine or its components, but with contradictory results. We have used the genotype instead of the phenotype (responsiveness to PROP or other tastants), to test the possible relation between genetic variability and the perception of wine characteristic in 528 subjects from Italy and the Czech Republic. We observed several interesting associations, among which the association between several TAS2R38 gene single nucleotide polymorphisms (P = 0.002) and the TAS2R16-rs6466849 polymorphism with wine sourness P = 0.0003). These associations were consistent in both populations, even though the country of origin was an important factor in the two models, thus indicating therefore that genetics alongside cultural factors also play a significant role in the individual liking of wine. more...

The increasing interest for adopting electromechanical actuators (EMAs) on aircraft demands improved diagnostic and prognostic methodologies to be applied to such systems in order to guarantee acceptable levels of reliability and safety. While diagnostics methods and techniques can help prevent fault propagation and performance degradation, prognostic methods can be applied in tandem to reduce maintenance costs and increase overall safety by enabling predictive and condition-based maintenance schedules. In this work, a predictive approach for EMAs friction torque estimation is proposed. The algorithm is based on the reconstruction of the residual torque in mechanical transmissions. The quantity is then sampled and an artificial neural network (ANN) is used to obtain an estimation of the current health status of the transmission. Early results demonstrate that such an approach can predict the transmission health status with good accuracy. more...

The ever increasing adoption of electrical power as secondary form of on-board power is leading to an increase in the usage of electromechanical actuators (EMAs). Thus, in order to maintain an acceptable level of safety and reliability, innovative prognostics and diagnostics methodologies are needed to prevent performance degradation and/or faults propagation. Furthermore, the use of effective prognostics methodologies carries several benefits, including improved maintenance schedule capability and relative cost decrease, better knowledge of systems health status and performance estimation. In this work, a novel, real-time approach to EMAs prognostics is proposed. The reconstructed back electromotive force (back-EMF), determined using a virtual sensor approach, is sampled and then used to train an artificial neural network (ANN) in order to evaluate the current system status and to detect possible coils partial shorts and rotor imbalances. more...

The development and validation of prognostic algorithms and digital twins for Electromechanical Actuators (EMAs) requires datasets of operating parameters that are not commonly available. In this context, we are assembling a test bench able to simulate different operating scenarios and environmental conditions for an EMA in order to collect the operating parameters of the actuator both in nominal conditions and under the effect of incipient progressive faults. This paper presents the design and manufacturing of a planetary gearbox for the EMA test bench. Mechanical components were conceived making extensive use of Fused Deposition Modelling (FDM) additive manufacturing and off-the-shelf hardware in order to limit the costs and time involved in prototyping. Given the poor mechanical properties of the materials commonly employed for FDM, the gears were not sized for the maximum torque of the electric motor, and a secondary torque path was placed in parallel of the planetary gearbox to load the motor through a disc brake. The architecture of the gearbox allowed a high gear ratio within a small form factor, and a bearingless construction with a very low number of moving parts. more...

Cell culture is usually performed in 2D polymer surfaces; however, several studies are conducted with the aim to screen functional coating molecules to find substrates more suitable for cell adhesion and proliferation. The aim of this manuscript is to compare the cell adhesion and cytoskeleton organization of different cell types on different surfaces. Human primary fibroblasts, chondrocytes and osteoblasts isolated from patients undergoing surgery were seeded on polystyrene, poly-d-lysine-coated glass and titanium carbide slides and left to grow for several days. Then their cytoskeleton was analyzed, both by staining cells with phalloidin, which highlights actin fibers, and using Atomic Force Microscopy. We also monitored the production of Fibroblast Growth Factor-2, Bone Morphogenetic Protein-2 and Osteocalcin, using ELISA, and we highlighted production of Collagen type I in fibroblasts and osteoblasts and Collagen type II in chondrocytes by immunofluorescences. Fibroblasts, chondrocytes and osteoblasts showed both an improved proliferative activity and a good adhesion ability when cultured on titanium carbide slides, compared to polystyrene and poly-d-lysine-coated glass. In conclusion, we propose titanium carbide as a suitable surface to cultivate cells such as fibroblasts, chondrocytes and osteoblasts, allowing the preservation of their differentiated state and good adhesion properties. more...