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This article addresses the classical problem of determining the extrinsic resistances ( $R_{G}$ , $R_{S}$ , and $R_{D}$ ) of field-effect transistors (FETs) and, in particular, of high-electron-mobility transistors (HEMTs). The presented approach relies on small-signal measurements of open-channel transistors, as often proposed both for traditional metal–semiconductor FETs (MESFETs) and HEMTs. Unlike what is common practice with HEMTs, the method proposed here does not oversimplify the model of the active channel. On the contrary, we retrieve from the literature a possible analytical model for the open-channel HEMT and use it to determine the triplet of extrinsic resistances without the need of stressing the gate junction with too high currents. Another result of the approach, valid both for MESFETs and HEMTs, is a deterministic way to remove the contribution of the gate junction from the small-signal parameters of the measured devices. All extractions process data that are available on suitable ranges in frequency or in bias voltage, without taking to the limit the sweep parameters or seeking specific resonances. Also, optimizations are only allowed to refine the nominal values, not as the main technique of extraction. These goals are achieved by setting up different subproblems in the form of overdetermined linear systems and then solving by pseudoinversion. The validity of the approach is demonstrated on the measurements of devices from advanced HEMT technologies realized by OMMIC, both GaAs-based (40-nm gate length) and GaN-based (100 and 60 nm).

In this letter, we present the design of a V- band low-noise amplifier for intersatellite crosslink receivers. The test vehicle, realized on industrial metamorphic gallium arsenide technology, operates from 57 to 66 GHz exhibiting 23-dB gain and an average 1.8-dB noise figure. Particular attention was devoted to the analysis and synthesis of an alternative bias injection topology to obtain a sharp gain roll-off at lower frequencies, thus avoiding the insertion, at system level, of an image-reject filter.

This work presents the design and characterization of an ultralow-power core chip for electronically scanned arrays at X-band, implemented in 0.25-/0.5-μm E-/D-mode gallium arsenide (GaAs) pHEMT technology. In particular, design details are given about the two core functional blocks embedded in the microwave monolithic integrated circuit (MMIC): a 12-bit phase and amplitude control circuit and an 18-bit serial-to-parallel (S2P) interface. The S2P interface was designed resorting to a custom symmetric device model, expressly conceived for the time-domain simulations required for digital circuits. Due to the adoption of a differential structure with resistive pull-ups, it achieves a state-of-the-art power consumption of 2.2 mW/bit and nearly 87% yield. The analog circuit includes a 6-bit phase shifter (PS) and a 6-bit attenuator. To mitigate risks, two different PS architectures have been developed and are compared in this work, discussing advantages and drawbacks of the different solutions. Since the two designs share the same target specifications, a truly fair comparison can be made not only in terms of performance but also concerning robustness and repeatability, thus providing useful guidelines for the selection of the most appropriate strategy. In particular, it is shown that one architecture outperforms the other by about 2 dB and 1.5° in terms of insertion loss and rms phase error, respectively.

To date, little is known regarding the transmission risks of SARS-CoV-2 infection for subjects involved in handling, transporting, and examining deceased persons with known or suspected COVID-19 positivity at the time of death. This experimental study aims to define if and/or how long SARS-CoV-2 persists with replication capacity in the tissues of individuals who died with/from COVID-19, thereby generating infectious hazards. Sixteen patients who died with/from COVID-19 who underwent autopsy between April 2020 and April 2021 were included in this study. Based on PMI, all samples were subdivided into two groups: ‘short PMI’ group (eight subjects who were autopsied between 12 to 72 h after death), ‘long PMI’ (eight subjects who were autopsied between 24 to 78 days after death). All patients tested positive for RT-PCR at nasopharyngeal swab both before death and on samples collected during post-mortem investigation. Moreover, a lung specimen was collected and frozen at −80 °C in order to perform viral culture. The result was defined based on the cytopathic effect (subjective reading) combined with the positivity of the RT-PCR test (objective reading) in the supernatant. Only in one sample (PMI 12 h), virus vitality was demonstrated. This study, supported by a literature review, suggests that the risk of cadaveric infection in cases of a person who died from/with COVID-19 is extremely low in the first hours after death, becoming null after 12 h after death, confirming the World Health Organization (WHO) assumed in March 2020 and suggesting that the corpse of a subject who died from/with COVID-19 should be generally considered not infectious.

This paper is focused on the extraction of the noise parameters of a linear active device by exploiting both forward and reverse noise power measurements associated with different terminations. In order for load-pull measurements to yield a significant marginal improvement (as compared to forward measurements only) it is expected that the device under test should appreciably deviate from unidirectionality. For this reason, the source/load-pull technique is applied to frequencies at which the considered devices are still usable but their reverse noise factor exhibits a measurable dependence on the output terminations. Details on the test bench set up to the purpose, covering the 20–40 GHz frequency range, are provided. A characterization campaign on a 60 nm gate length, 4×35 µm GaN-on-Si HEMT fabricated by OMMIC is illustrated.

Motivated by the growing interest towards low-cost, restriction-free MMIC processes suitable for multi-function, possibly space-qualified applications, this contribution reports the extraction of reliable linear models for two advanced GaN-on-Si HEMT technologies, namely OMMIC&rsquo, s D01GH (100 nm gate length) and D006GH (60 nm gate length). This objective is pursued by means of both classical and more novel approaches. In particular, the latter include a nondestructive method for determining the extrinsic resistances and an optimizaion-based approach to extracting the remaining parasitic elements: these support standard DC and RF measurements in order to obtain a scalable, bias-dependent equivalent-circuit model capturing the small-signal behavior of the two processes. As to the noise model, this is extracted by applying the well known noise-temperature approach to noise figure measurements performed in two different frequency ranges: a lower band, where a standard Y-factor test bench is used, and an upper band, where a custom cold-source test bench is set up and described in great detail. At 5 V drain-source voltage, minimum noise figures as low as 1.5 dB and 1.1 dB at 40 GHz have been extracted for the considered 100 nm and 60 nm HEMTs, respectively: this testifies the maturity of both processes and the effectiveness of the gate length reduction. The characterization and modeling campaign, here presented for the first time, has been repeatedly validated by published designs, a couple of which are reviewed for the Reader&rsquo, s convenience.

Background. The highly variable manifestation of the COVID-19 disease, from completely asymptomatic to fatal, is both a clinical and a public health issue. The criteria for discharge of hospitalized patients have been based so far on the negative result of Real-Time Reverse Transcriptase Polymerase Chain Reaction (RT-PCR) tests, but the persistence of viral fragments may exceed that of the integral virus by weeks. The aim of our study was to verify the clearance of the virus at viral culture in patients hospitalized for COVID-19 that have clinically recovered but are still positive on nasopharyngeal swab. Methods. The study was conducted in hospitalized patients with positive RT-PCR on nasopharyngeal swab. Patients included were from asymptomatic to severe cases and performed nasopharyngeal control swabbing on day 14 for asymptomatic patient or at least three days after remission of symptoms. RT-PCR positive specimens were sent to a biosafety level 3 laboratory for viral culture. Results. We performed a combined analysis of RT-PCR and a highly sensitive in vitro culture from 84 samples of hospitalized patients. The average age was 46 &plusmn, 20.29, and 40.5% of the subjects had radiologically confirmed pneumonia, with average PaO2 of 72.35 &plusmn, 12.12and P/F ratio of 315 &plusmn, 83.15. Ct values for the N gene were lower in the first swab than in the control one (p &lt, 0.001). The samples from 83 patients were negative at viral culture, and RT-PCR on the respective supernatants always confirmed the absence of viral growth. Conclusions. Our preliminary results demonstrate that patients clinically recovered for at least three days show the viral clearance at viral culture, and presumably they continued to not be contagious.

In this work, a Ka-Band MMIC LNA designed with two different gate length GaN-on-Si devices is shown. Measurements show a gain higher than 29dB, 2.1dB average NF in the 34÷37.5GHz design band and a 1dBcp around 23-24dBm in the 35÷36.5GHz target band, showing a good suitability to highgain, low-noise and medium-power requests. Comparison with GaN-on-SiC-based similar works confirms the feasibility of the adoption of GaN-on-Si technology for space-borne applications.

Design solutions and technology considerations of a 6–52 GHz cascode distributed amplifier are presented in this paper. The amplifier is designed in a Gallium Nitride on Silicon process with two different gate length transistors, namely 60 nm and 100 nm, connected in cascode configuration. The test vehicle, whose additional aim is to show the possibility to integrate transistors with different gate lengths onto the same chip, demonstrates 9 dB gain, 28 dBm saturated output power, 20% PAE and 37 dBm IP3, on average. Comparison with Gallium Nitride on Silicon Carbide based similar works reveals satisfactory performance obtained however on a cost effective and high volume production substrate.

In this paper, a Single-Chip Front-End (SCFE) operating in Ka-Band (35–36.5 GHz) is presented. Chip is designed exploiting a GaN-on-Si technology featured by 100nm gate length provided by OMMIC foundry. This MMIC integrates high-power, low-noise amplification functionalities enabled by a couple of synchronous Single-Pole Double-Throw (SPDT) switches, occupying a total surface of 4.7×3 mm2. Transmit-mode (Tx) performance present a 36 dBm output power, a Power Added Efficiency (PAE) higher than 25% and a 20dB power gain at 2 dB compression. Regarding the receiving-mode (Rx) performance, a sub-3.2 dB Noise Figure (NF) and a linear gain just below the 32 dB level is obtained, with a I/O matching better than 20 dB, as well.

Cannabis sativa, commonly known as marijuana, contains a pool of secondary plant metabolites with therapeutic effects. Besides Δ9-tetrahydrocannabinol that is the principal psychoactive constituent of Cannabis, cannabidiol (CBD) is the most abundant nonpsychoactive phytocannabinoid and may represent a prototype for anti-inflammatory drug development for human pathologies where both the inflammation and oxidative stress (OS) play an important role to their etiology and progression. To this regard, Alzheimer's disease (AD), Parkinson's disease (PD), the most common neurodegenerative disorders, are characterized by extensive oxidative damage to different biological substrates that can cause cell death by different pathways. Most cases of neurodegenerative diseases have a complex etiology with a variety of factors contributing to the progression of the neurodegenerative processes; therefore, promising treatment strategies should simultaneously target multiple substrates in order to stop and/or slow down the neurodegeneration. In this context, CBD, which interacts with the eCB system, but has also cannabinoid receptor-independent mechanism, might be a good candidate as a prototype for anti-oxidant drug development for the major neurodegenerative disorders, such as PD and AD. This review summarizes the multiple molecular pathways that underlie the positive effects of CBD, which may have a considerable impact on the progression of the major neurodegenerative disorders.

In an aging society, Alzheimer’s disease (AD) exerts an increasingly serious health and economic burden. Current treatments provide inadequate symptomatic relief as several distinct pathological processes are thought to underlie the decline of cognitive and neural function seen in AD. This suggests that the efficacy of treatment requires a multitargeted approach. In this context, palmitoylethanolamide (PEA) provides a novel potential adjunct therapy that can be incorporated into a multitargeted treatment strategy. We used young (6-month-old) and adult (12-month-old) 3×Tg-AD mice that received ultramicronized PEA (um-PEA) for 3 months via a subcutaneous delivery system. Mice were tested with a range of cognitive and noncognitive tasks, scanned with magnetic resonance imaging/magnetic resonance spectroscopy (MRI/MRS), and neurochemical release was assessed by microdialysis. Potential neuropathological mechanisms were assessed postmortem by western blot, reverse transcription–polymerase chain reaction (RT-PCR), and immunofluorescence. Our data demonstrate that um-PEA improves learning and memory, and ameliorates both the depressive and anhedonia-like phenotype of 3×Tg-AD mice. Moreover, it reduces Aβ formation, the phosphorylation of tau proteins, and promotes neuronal survival in the CA1 subregion of the hippocampus. Finally, um-PEA normalizes astrocytic function, rebalances glutamatergic transmission, and restrains neuroinflammation. The efficacy of um-PEA is particularly potent in younger mice, suggesting its potential as an early treatment. These data demonstrate that um-PEA is a novel and effective promising treatment for AD with the potential to be integrated into a multitargeted treatment strategy in combination with other drugs. Um-PEA is already registered for human use. This, in combination with our data, suggests the potential to rapidly proceed to clinical use.

In this paper a GaN-on-Si MMIC Low-Noise Amplifier (LNA) working in the Ka-band is shown. The chosen technology for the design is a 100 nm gate length HEMT provided by OMMIC foundry. Both small-signal and noise models had been previously extracted by the means of an extensive measurement campaign, and were then employed in the design of the presented LNA. The amplifier presents an average noise figure of 2.4 dB, a 30 dB average gain value, and input/output matching higher than 10 dB in the whole 34&ndash, 37.5 Ghz design band, while non-linear measurements testify a minimum output 1 dB compression point of 23 dBm in the specific 35&ndash, 36.5 GHz target band. This shows the suitability of the chosen technology for low-noise applications.

A MMIC demonstrator for RF phase and amplitude control with on board 18-bit serial to parallel conversion (Multi-Functional Chip) is presented. Thanks to an alternative digital building block topology, the DC power consumption of the digital serial to parallel converter is noteworthy: less than 43 mW (2 mW/bit). The main RF performances are 0° – 360° phase coverage and 0 dB – 31.5 dB attenuation setting, in the 7.6 GHz – 9.1 GHz operating bandwidth. The circuit, whose area is 6 mm2, is realised in an industrial and commercially available GaAs technology. This component can be used in active electronically scanned arrays for beam steering.

The feasibility of a W-band (81-86 GHz) downconverter for space-borne communications is verified in this paper through the design of a custom MMIC chip-set. The latter is composed of three functionalities: a low-noise amplifier (LNA), a sub-harmonically pumped mixer (SHM), and an active frequency doubler that provides the local oscillator (LO) pump to the mixer. The MMICs have been designed with OMMIC’s 70 nm and UMS’s 100nm GaAs technologies, in order to exploit the best-of-both technologies (low-noise and power-handling at millimetre-wave). The LNA features 23 dB gain and sub-2.5 dB Noise Figure in the whole operating band, while the mixer shows 13 dB conversion loss (CL). Finally, the active doubler provides > +10dBm pump at the necessary LO frequency.

In this paper, the feasibility of a V-band MMIC chipset is tested by the design of a Low-Noise Amplifier (LNA) operating in the 59-66 GHz frequency band and two Mixers exploiting two different topologies that convert signals from the 60-60.4 GHz band to 8-8.4 GHz band and vice versa. The MMICs have been designed exploiting OMMIC’s 70 nm and 130 nm GaAs technologies. LNA shows a 23 dB gain and a sub-2 dB Noise Figure in the whole operating band, while the two Mixers show a 11-12 dB conversion loss, along with LO isolation towards RF and IF port higher than 22 dB and a simulated Input 1 dB Compression Point of 10 dBm.

This paper provides an assessment between two MMIC foundry processes for millimetre-wave high-performance receiver applications, namely, OMMIC’s 70 nm GaAs and 60 nm GaN-on-Si processes. To do so, a characterization and modelling campaign was carried out on transistors provided by OMMIC for the two processes, whose commercial names are D007IH (70 nm GaAs) and D006GH (60 nm GaN). The resulting models were employed to design several test vehicle Low-Noise Amplifiers (LNA) operating above 30 GHz. The GaAs LNAs have been manufactured and characterized, while the GaN-on-Si LNAs are being manufactured. The initial outcome of the assessment is that GaAs is still ahead if Noise Figure is the crucial and mandatory requirement. GaN-on-Si, on the other hand, proves to be a viable solution if a – slightly – higher Noise Figure is acceptable. Moreover, the benefits of GaN-on-Si, with respect to GaAs, are higher robustness, output power, linearity, and higher integration capability with CMOS technologies.

In this paper a MMIC Low-Noise Amplifier operating in Ka-band is presented. The chosen technology is a 100 nm GaN HEMT on a High Resistivity Silicon substrate. A fully deterministic approach based on constant mismatch circles has been used for the preliminary synthesis of matching networks. The designed four-stages LNA presents a 33 dB gain, Input/Output matching better than 21 dB and a Noise Figure of no more than 2.3 dB in the whole operating band, showing the suitability of the chosen technology to low-noise, high gain and linearity applications.

In this paper, a times four K- to W-Band frequency multiplier involved in the generation of a Local Oscillator signal is presented. The chosen technology for this design is the D01MH, a metamorphic GaAs mHEMT with a 0.13 µm channel length. The designed MMIC is expected to convert a 5 dBm, 23–24 GHz input signal into a 11 dBm, 92–96 GHz output signal. Simulations show an output power harmonic suppression over 50 dBc between the desired and unwanted ones. Input and Output matching respectively better than 13 and 16 dB is expected. The MMIC occupies an area of 3 × 2 mm2, and is currently being manufactured.

Highlights • This is the first described case of isolation of Sars-CoV-2 in Vero E6 cell-culture from a 10-day-old newborn in Italy. • The infection was detected in the mother after the child was born and therefore a vertical transmission can be excluded. • Despite the presence of the virus, the newborn showed mild symptoms of the disease., This report describes the evolution of COVID-19 in a 10 day-old-baby. The mother developed the disease immediately after childbirth and therefore a vertical transmission can be excluded. The isolation of the virus in cell culture with a cytopathic effect already visible after 48 h, indicates that the viral load of the newborn was quite high, but not serious course of the disease was observed. This paper wants to highlight the possible role of newborns and children in the spread of the disease.

The discovery that mammalian target of rapamycin (mTOR) inhibition increases lifespan in mice and restores/delays many aging phenotypes has led to the identification of a novel potential therapeutic target for the treatment of Alzheimer's disease (AD). Among mTOR inhibitors, everolimus, which has been developed to improve the pharmacokinetic characteristics of rapamycin, has been extensively profiled in preclinical and clinical studies as anticancer and immunosuppressive agent, but no information is available about its potential effects on neurodegenerative disorders. Using a reliable mouse model of AD (3 × Tg-AD mice), we explored whether short-term treatment with everolimus injected directly into the brain by osmotic pumps was able to modify AD-like pathology with low impact on peripheral organs. We first established in non-transgenic mice the stability of everolimus at 37 °C in comparison with rapamycin and, then, evaluated its pharmacokinetics and pharmacodynamics profiles through either a single peripheral (i.p.) or central (i.c.v.) route of administration. Finally, 6-month-old (symptomatic phase) 3 × Tg-AD mice were treated with continuous infusion of either vehicle or everolimus (0.167 μg/μl/day, i.c.v.) using the osmotic pumps. Four weeks after the beginning of infusion, we tested our hypothesis following an integrated approach, including behavioral (tests for cognitive and depressive-like alterations), biochemical and immunohistochemical analyses. Everolimus (i) showed higher stability than rapamycin at 37 °C, (ii) poorly crossed the blood-brain barrier after i.p. injection, (iii) was slowly metabolized in the brain due to a longer t1/2 in the brain compared to blood, and (iv) was more effective in the CNS when administered centrally compared to a peripheral route. Moreover, the everolimus-induced mTOR inhibition reduced human APP/Aβ and human tau levels and improved cognitive function and depressive-like phenotype in the 3 × Tg-AD mice. The intrathecal infusion of everolimus may be effective to treat early stages of AD-pathology through a short and cyclic administration regimen, with short-term outcomes and a low impact on peripheral organs.

Future stringent emission legislation will require high efficient catalytical systems. Along with engine out emission reduction and advanced wash coat solution the substrate technology will play a key role in order to keep system costs as low as possible. The development of metallic substrates over the past few years has shown that turbulent-like substrates increase specific catalytic efficiency. This has made it possible to enhance overall performance for a specific catalytic volume or reduce the volume while keeping catalytic efficiency constant. This paper focuses on the emission efficiency of standard, TS (Transversal Structure) and LS (Longitudinal Structure) metallic substrates. In a first measurement program, standard TS and LS substrates have been compared using a 150cc 4 Stroke engine in dynamic (ECE R40) conditions. In a second test standard and LS substrate have been tested. Both TS and LS technologies show advantage compared to standard technology but have different application fields: TS is a cost effective solution for next emission limits while LS is a possible solution for future stringent emission limits.

Exposure to atmospheric pollution is a major concern for urban populations. Currently, no effective strategy has been adopted to tackle the problem. The paper presents the Smart Clean Air City project, a pilot experiment concerning the improvement in urban air quality. Small wet scrubber systems will be operating in a network configuration in suitable urban areas of L’Aquila city (Italy). The purpose of this work is to describe the project and show the preliminary results obtained in the characterization of two urban sites before the remediation test; the main operating principles of the wet scrubber system will be discussed, as well as the design of the mobile treatment plant for the processing of wastewater resulting from scrubber operation. Measurements of particle size distributions in the range of 0.30–25 µm took place in the two sites of interest, an urban background and a traffic area in the city of L’Aquila. The mean number concentration detected was 2.4 × 107 and 4.5 × 107 particles/m3, respectively. Finally, theoretical assessments, performed by Computational Fluid Dynamics (CFD) codes, will show the effects of the wet scrubber operation on air pollutants under different environmental conditions and in several urban usage patterns.

Modern Diesel Engines equipped with Common-Rail Direct Injection and EGR are characterized by an increasingly high combustion efficiency. Consequently the exhaust gas temperature, especially during a cold start, is significantly reduced compared to typical values measured in previous engine generations. This leads to a potential problem with CO emission limit compliance. The present paper deals with an experimental investigation of turbulent-flow metal substrates, carried out on a vehicle roller bench using a production 1.3 Liter diesel engine equipped passenger car. The tested metal supported catalysts proved to yield extremely high conversion rates both during cold start and in warm operation phase. The improved mass transfer efficiency of the advanced metal substrates is related on one hand to the optimized coating technology and, on the other hand, to the enhanced flow performance in the single converter channels which is caused by structured metal foils. Additionally different cost saving scenarios have been analyzed by means of both catalyst volume reduction and decreased PGM loading.

Future stringent emission levels for NOx and PM will lead to the introduction of innovative combustion processes for diesel engines, such as premixed combustion, with the results to enhance the engine out emission of HC and CO. Therefore very efficient oxidation catalyst will be needed to face this possible issue. This paper deals with the optimization of a EU IV exhaust system by means of innovative metal supported catalyst, as for example the Pre Turbo Catalyst and the Hybrid Catalyst in combination with dedicated catalyst coatings. Moreover a base study over the use of PMFilter Catalyst has been made, to show the efficiency of such a device with EU IV engine calibration. The second part of the paper deals with the turbulent like structured foils substrates to have an even more efficient diesel oxidation catalyst with very high volumetric efficiency.

Future emission legislation can be met through substantial improvement in the effectiveness of the exhaust gas after-treatment system, the engine and the engine management system. For the catalytic converter, differentiation is necessary between the cold start behavior and the effectiveness at operating temperature. To be catalytically effective, a converter must be heated by the exhaust gas up to its light-off temperature. The major influential parameter for the light-off still is the supply of heat from the exhaust gas. Modification of the cold start calibration of engine control such as spark retard or increased idle speed can increase the temperature level of the exhaust gas. One further possibility is represented by a reduction of the critical mass ahead of the catalyst (exhaust manifold and pipe). Nevertheless the best measure to obtain optimal cold start effectiveness still seems to be locating the converter close to the engine. Depending on the individual application, limited installation space may only be available. Therefore the design target is a low volume, high effective catalyst with optimized thermodynamic properties to obtain maximum advantage of the thermal energy coming from the exhaust gases. The present paper deals with the cold start of a generic test cycle that can be subdivided in different phases, each characterized by different design parameters of the converter that are to be specifically tailored in order to achieve the maximum possible overall efficiency for the whole test.

The effects of the internal geometry of catalytic converter channels on flow characteristics; exhaust backpressure and overall conversion efficiency have been investigated by means of both numerical simulations and experimental investigations. The numerical work has been carried out by means of a micro scale numerical tool specifically tailored for flow characteristics within converter channels. The results are discussed with aid of flow distribution patterns within the single cell and backpressure figures along the catalyst channel.

The aim of this work was to obtain the correct hydraulic proprieties of a hydraulic spool servo-valve using computational fluid-dynamics (CFD) techniques and adopting an accurate enough mesh to analyse the flow pattern inside the valve. The zones where thickening of the mesh is necessary have been detected and a method to generate the mesh, based on Reynolds numbers and spool stroke, has successfully been used to minimize computational resources. A comparison with numerical and experimental results (Dong and Ueno, 1999) confirms the accurate description of the behaviour of the valve. The results have been compared with the theoretical behaviour, through a 1D multi-physics model simulation, in order to understand in which conditions the theoretical model is not able to describe the valve properties carefully enough and a more accurate CFD model should be used. As CFD analysis requires high computational resources, a method to improve 1D model accuracy through CFD techniques has been proposed, so th...

In order to identify incipient failures due to a progressive wear of a primary flight command electromechanical actuator, several approaches could be employed; the choice of the best ones is driven by the efficacy shown in fault detection/identification, since not all the algorithms might be useful for the proposed purpose. In other words, some of them could be suitable only for certain applications while they could not give useful results for others. Developing a fault detection algorithm able to identify the precursors of the abovementioned electromechanical actuator (EMA) failure and its degradation pattern is thus beneficial for anticipating the incoming malfunction and alerting the maintenance crew such to properly schedule the servomechanism replacement. The research presented in the paper was focused to develop a fault detection/identification technique, able to identify symptoms alerting that an EMA component is degrading and will eventually exhibit an anomalous behavior, and to evaluate its potential use as prognostic indicator for the considered progressive faults (i.e. frictions and mechanical backlash acting on transmission, stator coil short circuit, rotor static eccentricity). To this purpose, an innovative model based fault detection technique has been developed merging several information achieved by means of Fast Fourier Transform (FFT) analysis and proper "failure precursors" (calculated by comparing the actual EMA responses with the expected ones). To assess the performance of the proposed technique, an appropriate simulation test environment was developed: the results showed an adequaterobustness and confidence was gained in the ability to early identify an eventual EMA malfunctioning with low risk of false alarms or missed failures.