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Introduction Brucellosis is a widespread zoonosis of great economic importance for livestock farming in many areas of the world. It is a highly infectious disease which is diagnosed using conventional serological and microbiological methods. The aim of this study was to assess the efficiency of a specific real-time PCR in combination with broth cultivation in detecting Brucella spp. in organs of infected cattle, in order to compare the sensitivity of the two approaches and the time needed in them until a correct diagnosis is made. Material and Methods We examined 67 organs collected from 10 cattle slaughtered following a brucellosis outbreak which occurred in February 2016 in southern Italy. The research was carried out by enrichment broth cultivations in combination with a real-time PCR every week for six weeks. Results Brucella strains were isolated by cultivation from 44 enrichment broths of organs. All isolates were later identified as Brucella abortus by real-time PCR. Using this method in combination with cultivation made it possible to identify the same percentage of infected animals faster than by cultivation alone. Moreover, the same diagnostic results were obtained, on average two weeks before they would have been using only cultivation. In almost all cases, Brucella was detected by real-time PCR after the first week of cultivation in pre-enrichment Brucella broth, while the bacterial growth was evident usually after 2 or 3 weeks. Conclusion Real-time PCR has allowed results to be obtained faster than in the classical microbiological method, reducing the response times to identify positive animals by half.

The tightening trend of regulations on the levels of admitted pollutant emissions has given a great spur to the research work in the field of combustion and after-treatment devices. Despite the improvements that can be applied to the development of the combustion process, pollutant emissions cannot be reduced to zero; for this reason, the aftertreatment system will become a key component in the path to achieving near-zero emission levels.This study focuses on the numerical analysis and optimization of different metallic substrates, specifically developed for three-way catalyst (TWC) and Diesel oxidation catalyst (DOC) applications, to improve their thermal efficiency by reducing radial thermal losses through the outer mantle. The optimization process relies on computational fluid dynamics (CFD) simulations supported by experimental measurements to validate the numerical models carried out under uncoated conditions, where chemical reactions do not occur. Full-scale three-dimensional, multi-region models precisely describe the flow and temperature distributions allowing the evaluation of heat fluxes with the surrounding environment.A test cycle was designed to replicate the typical warm-up of a catalyst followed by a drop in the gas temperature and then a drop in the mass flow, replicating the engine switch-off condition.Different canning solutions and insulation strategies were considered at both numerical and experimental levels, and the results were compared. This allowed the validation of the numerical approach and identification of the best solution in terms of heat loss reduction and response time to heat up.

Source degenerative feedback is extensively applied in the low-noise amplifier design. The beneficial effects of this technique are well established in the open literature. However, the designer is often left to trial-and-error or optimization procedures to identify the adequate amount of feedback when other linear requirements, such as signal matching, come into play. This issue is even more relevant in multistage designs. In this article, we present a synthesis procedure and the relevant design chart to identify the optimum feedback inductor value on all transistors of an $N$ -stage amplifier to obtain a perfect match at its external ports in conjunction with amplifier noise figure minimization and a specified gain requirement. It is shown that the method is applicable to arbitrary $N$ values although it becomes more elaborate for $N$ greater than 6. The method is deterministic as opposed to optimization or trial-and-error-based procedures. The design flow is illustrated at first through a four-stage design with ideal matching elements and subsequently validated by an monolithic microwave integrated circuit (MMIC) test vehicle designed and realized in the WIN foundry’s Gallium Arsenide PIH1-10 process. The measured performance of the test vehicle is NF = 1.9 dB, 26 dB gain, typical I/O return loss of 15 dB in the 26.5–29.5-GHz bandwidth, and practically ideal behavior at the design frequency of 28 GHz.

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.

In this study, we cultured the

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.

Matrix-Assisted Laser Desorption/Ionization Time Of Flight Mass Spectrometry (MALDI-TOF MS) technology is currently increasingly used in diagnostic laboratories as a cost effective, rapid and reliable routine technique for the identification and typing of microorganisms. In this study, we used MALDI-TOF MS to analyze a collection of 160 strains belonging to the Bacillus cereus group (57 B. anthracis, 49 B. cereus, 1 B. mycoides, 18 B. wiedmannii, 27 B. thuringiensis, 7 B. toyonensis and 1 B. weihenstephanensis) and to detect specific biomarkers which would allow an unequivocal identification. The Main Spectra Profiles (MSPs) were added to an in-house reference library, expanding the current commercial library which does not include B. toyonensis and B. wiedmannii mass spectra. The obtained mass spectra were statistically compared by Principal Component Analysis (PCA) that revealed seven different clusters. Moreover, for the identification purpose, were generated dedicate algorithms for a rapid and automatic detection of characteristic ion peaks after the mass spectra acquisition. The presence of specific biomarkers can be used to differentiate strains within the B. cereus group and to make a reliable identification of Bacillus anthracis, etiologic agent of anthrax, which is the most pathogenic and feared bacterium of the group. This could offer a critical time advantage for the diagnosis and for the clinical management of human anthrax even in case of bioterror attacks.

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.

This work is focused on the design of broadband amplifiers by exploiting dissipative reciprocal matching networks. Unlike the classical approach, which makes use of lossless reciprocal matching networks, there is no need to trade-off the gain flatness with the input/output matching levels. In this contribution the flat gain condition is obtained partially by exploiting the mismatch loss at a certain section and partially by leveraging on ohmic losses. In particular, two different matching schemes have been analytically studied. Taking advantage of the more promising scheme of the two presented, the design of a linear power amplifier operating over the 4–40 GHz decade, is illustrated. The amplifier showed measured input/output return loss better than 9/10 dB respectively, a gain of 8 ± 0.6 dB and an output power level of 25.5 ± 0.5 dBm at 1 dB compression point. Incidentally, unconditional stability is obtained without considering additional stabilization networks or components devoted to the purpose.

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.

Recently, insulin-like growth factor binding protein 6 (IGFBP-6) has been shown to play a putative role in the immune system, as monocyte-derived dendritic cells (Mo-DCs) are stimulated by hyperthermia to express IGFBP-6 at both the mRNA and protein levels. However, the presence of IGFBP-6 in extracellular vesicles (EVs) and whether other pro-inflammatory stimuli can induce IGFBP-6 expression in Mo-DCs are not known yet. In this brief report, we show that hyperthermia (39°C) induces IGFBP-6 secretion associated with microvesicles and exosomes as early as 3 h. Moreover, free IGFBP-6 is found in conditioned media (CM) of hyperthermia- and H2O2-treated Mo-DCs, but not in CM obtained from monocytes similarly treated. These results show that diverse inflammatory stimuli can induce IGFBP-6 association with EVs and secretion in conditioned medium, indicating a role for IGFBP-6 in communication between immune cells.

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.

Global automotive fuel economy and emissions pressures mean that 48 V hybridisation will become a significant presence in the passenger car market. The complexity of powertrain solutions is increasing in order to further improve fuel economy for hybrid vehicles and maintain robust emissions performance. However, this results in complex interactions between technologies which are difficult to identify through traditional development approaches, resulting in sub-optimal solutions for either vehicle attributes or cost. The results presented in this paper are from a simulation programme focussed on the optimisation of various advanced powertrain technologies on 48 V hybrid vehicle platforms. The technologies assessed include an electrically heated catalyst, an insulated turbocharger, an electric water pump and a thermal management module. The novel simulation approach undertaken uses an integrated toolchain capturing thermal, electrical and mechanical energy usage across all powertrain sub-systems. Through integrating 0-D and 1-D sub-models into a single modelling environment, the operating strategy of the technologies can be optimised while capturing the synergies that exist between them. This approach enables improved and more informed cost/benefit ratios for the technologies to be produced and better attributes by identifying the optimum strategy for the vehicle. The results show the potential for CO2 reductions in the range of 2-5% at no additional cost, through co-optimisation of the technologies in a single simulation environment. The simulation work forms part of the THOMSON project, a collaborative research project aiming to develop cost effective 48 V solutions, in order to reduce the environmental impact of the transportation sector.