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In motor drive applications, single-stage current source inverters (CSIs) can manage only a limited speed range when the output voltage is greater than input voltage, due to the intrinsic boost capability. The classical solution adopted in low-speed region to control the input dc current, consists in the insertion of a prestage power converter. This article proposes a single-stage CSI that replaces the input inductance $L_{\text{dc}}$ with coupled inductor. In this way, it is possible to add the needed time interval for the discharge of the magnetic energy of primary inductance $L_{m}$ when the converter works in low-speed region or at standstill, extending the operating region of the converter. This solution allows to increase the efficiency of traditional CSIs for applications when the motor works most of the time in the high-speed region, thanks to the single-stage power conversion. Experimental and simulation results driving a permanent magnet synchronous machine are shown, confirming the validity of the proposed architecture.

This article introduces a novel data acquisition system aimed at condition monitoring (CM) of complex industrial machinery and plants. Current commercial solutions can be divided into two groups: 1) high resolution and 2) data rate rack systems or distributed systems usually at the price of lower performance. The proposed solution aims at filling this gap. It relies on a daisy-chain digital bus architecture, featuring a main node and a series of subordinate nodes, which have been designed to collect data from both analog and digital transducers. It follows that the system is highly scalable and easily reconfigurable: the number and the type of transducers, ranging from low-cost micro electromechanical systems to high quality piezoelectric sensors, can be optimized to match each specific measurement requirements, even after the installation of the system. The proposed technology supports up to 32 channels at 48 kS/s, and guarantees the perfect synchronization of all signals regardless of the transducer type and its position along the bus, allowing to perform advanced data analysis. The system performance is at first evaluated with laboratory tests, then in the scenario of CM of rolling bearing faults, demonstrating good sensitivity and coherence between different accelerometer types.

•B-cell suppressor treatments are associated with the risk of breakthrough COVID-19 in our cohort.•We did not observe any case of severe COVID-19: vaccination fully protected our cohort of people with multiple sclerosis against severe breakthrough disease.•B-cell suppressor treatments and EDSS were factors associated with low antibody titers after vaccination.

Brain amyloid deposition is one of the main hallmarks of Alzheimer’s disease (AD) and two approaches are available for assessing amyloid pathology in vivo: cerebrospinal fluid (CSF) biomarkers levels and amyloid load visualized by amyloid beta positron emission tomography imaging (Amy-PET) probes. We aimed to investigate the concordance between CSF biomarkers and Amy-PET in a memory clinic cohort. Moreover, using a proper clinical follow-up, we wanted to assess the diagnostic accuracy of CSF and PET biomarkers in predicting the progression of patients with mild cognitive impairment (MCI) to AD dementia. We included 31 MCI patients who underwent [18F]florbetaben PET and CSF sampling (Aβ1–42, t-Tau, p-Tau). A semiquantitative visual scan assessment was used to quantify amyloid deposition in 5 brain regions, rating from 1 (negative), to 2 and 3 (positive). CSF biomarkers were considered abnormal if: Aβ1–42 < 600 pg/ml, p-Tau/Aβ1–42 > 0.08 and t-Tau/Aβ1–42 > 0.52. We also applied less lenient cutoffs of 550 pg/ml and 450 pg/ml for Aβ1–42. The concordance rate was 77% between Amy-PET and CSF Aβ1–42 levels, and 89% between Amy-PET and p-Tau/Aβ1–42 and t-Tau/Aβ1–42. According to the clinical follow-up, Amy-PET (sensitivity [SE] 93.7%, specificity [SP] 80%) exhibited the best diagnostic accuracy in discriminating AD from non-AD, followed by p-Tau/Aβ1–42 ratio and t-Tau/Aβ1–42 ratio (SE 93.7%, SP 66.6%), and Aβ1–42 levels (SE 81%, SP 60%). The regional uptake of [18F]florbetaben PET in the precuneus and the striatum showed the best SP (86.6%). In discordant cases, the clinical diagnosis was most often in agreement with PET results. In general, concordance between CSF biomarkers and Amy-PET was good, especially when the ratios between CSF amyloid and Tau biomarkers were used. However, Amy-PET proved to be superior to CSF Aβ1–42 in terms of diagnostic accuracy for AD, with the possibility to further increase its specificity by focusing the analysis in specific areas such as the precuneus/posterior cingulate cortex and the striatum.

Multiphase CT angiography (CTA) in collateral assessment provides time-resolved cerebral angiograms of the intracranial vasculature, requiring a high-speed multidetector CT (MDCT) scanner with ≥ 64 slices. Unfortunately, many hospitals are equipped with lower speed MDCT scanners. Herein, we present our experience performing dual-phase CTA (d-CTA) on a 16 slice MDCT with a biphasic rate injection to grade intracranial collaterals as predictor of clinical outcome. 42 patients were evaluated with both dual-phase CTA (d-CTA) and single-phase CTA (s-CTA) for occluded anterior intracranial circulation and collaterals. They were treated with endovascular reperfusion. Univariate and multivariate analyses were performed to define the independent predictors for favorable outcome at 3 months. Good collateral circulation status on d-CTA was associated with a lower median 24-h (5 vs. 7.5, p= 0.03) and discharge (2 vs. 4.6, p= 0.04) NIHSS. A logistic regression model showed that only age (OR 0.95, 95% CI 0.91–0.98, p= 0.03) and good collateral circulation status at d-CTA (OR 4.3, 95% CI 1.87–11.3, p< 0.01) were independent predictors of favorable functional outcome at 3 months, but that s-CTA was not. The collateral status on d-CTA can be a useful predictor for clinical outcome in acute stroke patients. The proposed protocol adapted to a low-speed MDCT scanner could be of particular interest in hospitals without access to the more up-to-date technology.

Backgroound It’s Known that atrial fibrillation ( AF) is related to 20 % of ischemic stroke, but it is also found in one third of cryptogenetic, lacunar, atherotrombotic stroke. After stroke cardiac test are reccomended . 24 h holter ECG has a diagnostic yield about 1 – 5 % .Nowadays exists diagnostic test for ECG monitoring with a major diagnostic yield, but they are reccomended only in selected stroke patients

•PM2.5, PM10 and NO2 are risk factors for Covid-19 pneumonia among MS patients.•We studied the joint exposure to the three pollutants as an environmental mixture.•The most dangerous pollutants within the mixture were NO2 and PM2.5.

•The aim of this study was to construct such score and to evaluate its performance.•3852 patients were included in the study and 17% of the patients required hospitalization.•This score can be used as an additional instrument to identify high-risk patients and persuade them to take important measures to prevent Covid-19 infection.

•Cognitive profile and physician-based and patients-reported outcomes could have a considerable impact on the disease management and on treatment decision making•According to the Control Preference Scale, more than 50% of patients who needed to change therapy chose a “collaborative” role in making treatment decision.•Cognitive profile with SDMT seems to influence patients’ preference on treatment decision.

Interferon-ββ1a (IFN-ββ1a) and pentoxifylline (PTX) are reported to be active in relapsing-remitting multiple sclerosis (RRMS), but the mechanisms are not completely understood. In two groups of RRMS patients, we studied the phenotype of peripheral lymphocytes and the level of several cytokines both in sera and in supernatants of activated peripheral blood mononuclear cells (PBMC) before and after 8 months of therapy with IFN-ββ1a alone or associated with PTX. Our data indicate that patients with RRMS, treated with IFN-ββ1a, exhibited a significant increase in CD4+CD25++T suppressor cells, accompanied by a significant decrease in cytotoxic lymphocytes (CD8+CD28−−and natural killer [NK] cells) and IFN-γγ production, which could both contribute to an explanation of the previously described beneficial effects of IFN-ββ treatment in MS. The addition of PTX to IFN-ββ1a treatment did not modify the immunomodulatory effects obtained with IFN-ββ1a alone. Future studies are needed to demonstrate which immunologic parameters correlate with the clinical benefit of IFN-ββ1a treatment.

In this paper the contrasting effects of transmission impairments and capture on both the network and single user performance of a slotted Aloha system are investigated in a mobile radio environment, accounting for frequency non-selective random propagation phenomena, and employing the packet error probability in order to define packet losses and capture. With this study we demonstrate that it is possible to generalize in a real propagation context a method previously proposed in literature for evaluating the network behavior in terms of steady-state throughput, backlog and stability in conventional transmission conditions, i.e., when all the transmission channels were error-free and the collisions caused the loss of all the packets involved. Moreover, we indicate under which specific constraints on the terminal mobility we can apply this method to analytically predict the single user performance, which we show being an important design parameter. Through the numerical results reported we quantitatively point out that in the absence of coding capture increases system stability and moderately improves the overall system throughput and backlog. We also outline the trade-off between an increased capture gain obtained by means of coding and the corresponding system cost in terms of complexity and bandwidth occupancy. Furthermore, we demonstrate the unfairness which affects the single user performance and the consequent need for countermeasures in order not to discriminate among users differently located within the network; yet, this last solution is detrimental as regards the positive capture effects.

This work shows it is possible to apply for the performance evaluation of FDMA‐CDMA cellular mobile systems a simple analytical approximated method, previously successfully proposed by two of the authors with reference to FDMA‐TDMA systems. The distinctive feature of the methodology we describe is that it allows for an immediate determination of both the indexes traditionally employed to define system performance, i.e., average bit error probability eand outage probability Poutat a very low computational cost. The hypothesis required to apply the proposed approximation is that the examined spread spectrum system be characterized by a bandwidth occupancy lower than the coherence bandwidth of the transmission channel. This could be the case of a wireless DS‐CDMA system envisioned to provide voice service and exploiting a processing gain of the order of a hundred. We apply our methodology to determine the performance improvements in both eand Poutintroduced increasing the protection of the transmitted information through error correcting codes and interleaving, in different operating conditions as regards the functioning of the power control loops. A comparison is also satisfyingly carried out with some other approximated analytical methods found in literature. We strongly point out that the corresponding results are achieved at a much more modest computational cost than in traditional approaches.

AbstractThe objective of the present work was to develop calibration equations for the prediction of chemical composition and forage digestibility from different populations of alfalfa hay harvested in Parmigiano-Reggiano cheese production area of Northern Italy. Due to annual climatic variations that affect soil and growing conditions and consequently cause high variability in chemical and physical composition, 319 hay samples from four years were used to build robust calibration. NIRS calibration equations were developed for the prediction of in vitroNDF digestibility (IVNDFd) and 20 chemical parameters (dry matter, starch, fat, sugar, fiber fractions, crude protein, nitrogen fractions and some minerals) of Italian hay. The results obtained show that NIRS equations greatly explain the variation in the composition existing in alfalfa hays grown in Northern Italy, except for a few parameters characterized by low variability range value. The equations obtained for the prediction of biological and chemical parameters explain the major part of the variation existing in the reference data, which open great prospects for the use of NIRS in planning feeding strategies of livestock, based on alfalfa forage.

•The introduction of increasingly effective treatments has changed the MS scenario.•This study investigated the reasons that brought about modification of treatment.•In our study, out of 13,657 patients, 336 (3%) modified treatment.•90.2% switched, 8.9% temporarily discontinued, and 0.9% permanently discontinued.•Efficacy remains the main driving force behind switching in 58.4% of patients.

A simulation program has been carried out to further check the simplified method proposed by Immovilli and Merani for the analytical evaluation of outage probability in cellular mobile radio systems, due to cochannel interference and random propagation phenomena, nonselective in type. The results of the two different procedures show an excellent agreement.

The effects of cochannel interference in a mobile radio network are investigated, to highlight a method with which to analytically evaluate the corresponding outage probability in an extremely simplified manner. The general methodology presented can in particular be applied when Rayleigh fading, log-normal shadowing and path losses larger than those in free space are considered.

A Bi2O3compound which is unknown to date has been synthesized at 800 ?C on a BeO substrate. ?-Bi2O3at 800 ?C undergoes a phase transition to a metastable new compound named ?-Bi2O3which in turn transforms to stable ?-Bi2O3at 900 ?C. X-ray powder diffraction data were collected, indexed, and refined in order to obtain a unit cell (probable space group P1?: a=7.2688(4), b=8.6390(6), c=11.9698(8) ?, ?=87.713(6), ?=93.227(6), ? =86.653(4)?. This compound is of interest for the thick films circuits and sensors technology.

Background As yet, no population-based prospective studies have been conducted to investigate the incidence and clinical outcome of glioblastoma (GBM) or the diffusion and impact of the current standard therapeutic approach in newly diagnosed patients younger than aged 70 years. Methods Data on all new cases of primary brain tumors observed from January 1, 2009, to December 31, 2010, in adults residing within the Emilia-Romagna region were recorded in a prospective registry in the Project of Emilia Romagna on Neuro-Oncology (PERNO). Based on the data from this registry, a prospective evaluation was made of the treatment efficacy and outcome in GBM patients. Results Two hundred sixty-seven GBM patients (median age, 64 y; range, 29–84 y) were enrolled. The median overall survival (OS) was 10.7 months (95% CI, 9.2–12.4). The 139 patients ≤aged 70 years who were given standard temozolomide treatment concomitant with and adjuvant to radiotherapy had a median OS of 16.4 months (95% CI, 14.0–18.5). With multivariate analysis, OS correlated significantly with KPS (HR = 0.458; 95% CI, 0.248–0.847; P = .0127), MGMT methylation status (HR = 0.612; 95% CI, 0.388–0.966; P = .0350), and treatment received in a high versus low-volume center (HR = 0.56; 95% CI, 0.328–0.986; P = .0446). Conclusions The median OS following standard temozolomide treatment concurrent with and adjuvant to radiotherapy given to (72.8% of) patients aged ≤70 years is consistent with findings reported from randomized phase III trials. The volume and expertise of the treatment center should be further investigated as a prognostic factor.

Defibrotide has been shown to be effective in the treatment and prophylaxis of the VOD,a relatively common complication after allogeneic hematopoietic stem cell transplantation(SCT).We report our experience in 41 consecutive patients(pts) for a total of 43 SCT.The analysis,closed at day +35 after BMT,is limited to 39 SCT,since 4 pts not affected by VOD died on day +3,+11,+13 and +24,respectively.The pts(mean age 42 yrs,range 16–65) were affected by acute leukemia(14), chronic myeloid leukemia(5),lymphoma(15),multiple myeloma(2),myelodisplasia(1) and solid tumor(2).Other relevant clinical characteristics were:resistant or metastatic disease 9,previous autologous BMT 6,previous allogeneic SCT 2,previous B virus hepatitis 5,liver metastases 1 and lymphoma of the liver 1.All were transplanted from their HLA-identical sibling;the conditioning regimen was defined as reduced in 15(thiotepa,fludarabine and cyclophosphamide),while it was conventional in the other 24 SCT with use of busulphan(oral 13 and iv 11) and cyclophosphamide(VP16 added in few cases;never TBI). Thirteen received bone marrow and 26 peripheral blood as source of stem cells.No T-cell depletion was done and the GVHD prophylaxis regimen was CsA+MTX for 36 pts, CsA alone for 2 pts and FK506+MTX for 1 patient.For VOD prophylaxis no Heparin was administered,while Defibrotide was given at the dosage of 10 mg/Kg in continuous iv infusion starting on day +1 until day +21 after the SCT.Defibrotide was very well tolerated,and no hemorrhagic complications were observed.Blood coagulation significant alterations were:prolonged PT(4/39),prolonged aPTT(3/39),fibrinogen elevated(23/39,never over 800 mg/dl),low level(less than 50%) of ATIII,and/or protein C,and/or protein S(2/39).By using the VOD Baltimore criteria,only 1 case of VOD was observed at day +29 in a patient who died at day +36 with VOD,aspergillosis and CMV pneumonia.The bilirubin was more than 2 times the normal value in 20/39;US scan of the liver and Doppler,performed in 15 pts with a possibile sign of VOD,was positive only in the patient who died for VOD.We documented 29 infectious complications(14 FUO,9 gram positive bacteremias,2 pneumonia and 4 invasive aspergillosis).We observed acute GVHD in 10 pts(9 grade I–II and 1 grade III).Five pts died between +36 and +100 but none for VOD(3 for progression of their disease and 2 for aspergillosis).Since in this at risk transplanted population only 1 VOD has been observed,Defibrotide low-dose continous infusion, not associated with Heparin,seems able to play a relevant role in the VOD prophylaxis.On considering the favourable results obtained by us and Others,the absence of toxicity and the low cost of Defibrotide,we intend to continue this experience with defibrotide as VOD prophylaxis,even if we foretell a large randomized study to find better indications.