Radial force control in electrical machines has been widely investigated for a variety of bearingless machines, as well as for the conventional structures featuring mechanical bearings. This paper ...takes advantage of the spatial distribution of the winding sets within the stator structure in a multisector permanent-magnet (MSPM) machine toward achieving a controllable radial force. An alternative force control technique for MSPM machines is presented. The mathematical model of the machine and the theoretical investigation of the force production principle are provided. A novel force control methodology based on the minimization of the copper losses is described and adopted to calculate the d-q axis current references. The predicted performances of the considered machine are benchmarked against finite-element analysis. The experimental validation of the proposed control strategy is presented, focusing on the suppression of selected vibration frequencies for different rotational speeds.
Some Lactobacillus strains may contribute to the health of the host when administered in adequate concentrations, demonstrating their probiotic potential. In contrast, Listeria monocytogenes is a ...foodborne pathogen that can cause enteropathy, meningoencephalitis, abortion, and septicemia. The aim of this survey was to evaluate the in vitro and in vivo probiotic potential of Lactobacillus plantarum B7 and Lactobacillus rhamnosus D1, isolated from Minas artisanal cheese of the Serra da Canastra (Minas Gerais, Brazil), against Lis. monocytogenes. We submitted B7 and D1 to in vitro testing (antibiogram, tolerance to bile salts and artificial gastric fluid, and spot-on-lawn) and in vivo testing (relative weight gain in mice). Both Lactobacillus strains demonstrated in vitro inhibitory activity against Lis. monocytogenes, as well as sensitivity to antimicrobials and resistance to gastric acids and bile salts. In the in vivo assays, mice treated with D1 gained more weight than mice in the other groups. These results indicate that D1 could have higher probiotic potential than B7 because improvements in feed conversion may help animals fight infection.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Treatment failure in pneumococcal meningitis due to antibiotic resistance is an increasing clinical challenge and alternatives to antibiotics warrant investigation. Phage-derived endolysins ...efficiently kill gram-positive bacteria including multi-drug resistant strains, making them attractive therapeutic candidates. The current study assessed the therapeutic potential of the novel endolysin PlyAZ3aT in an infant rat model of ceftriaxone-resistant pneumococcal meningitis.
Efficacy of PlyAZ3aT was assessed in a randomized, blinded and controlled experimental study in infant Wistar rats. Meningitis was induced by intracisternal infection with 5 x 107 CFU/ml of a ceftriaxone-resistant clinical strain of S. pneumoniae, serotype 19A. Seventeen hours post infection (hpi), animals were randomized into 3 treatment groups and received either (i) placebo (phosphate buffered saline PBS, n = 8), (ii) 50 mg/kg vancomycin (n = 10) or (iii) 400 mg/kg PlyAZ3aT (n = 8) via intraperitoneal injection. Treatments were repeated after 12 h. Survival at 42 hpi was the primary outcome; bacterial loads in cerebrospinal fluid (CSF) and blood were secondary outcomes. Additionally, pharmacokinetics of PlyAZ3aT in serum and CSF was assessed.
PlyAZ3aT did not improve survival compared to PBS, while survival for vancomycin treated animals was 70% which is a significant improvement when compared to PBS or PlyAZ3aT (p<0.05 each). PlyAZ3aT was not able to control the infection, reflected by the inability to reduce bacterial loads in the CSF, whereas Vancomycin sterilized the CSF and within 25 h. Pharmacokinetic studies indicated that PlyAZ3aT did not cross the blood brain barrier (BBB). In support, PlyAZ3aT showed a peak concentration of 785 μg/ml in serum 2 h after intraperitoneal injection but could not be detected in CSF.
In experimental pneumococcal meningitis, PlyAZ3aT failed to cure the infection due to an inability to reach the CSF. Optimization of the galenic formulation e.g. using liposomes might enable crossing of the BBB and improve treatment efficacy.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Context. Radio loud active galactic nuclei (AGN) are episodic in nature, cycling through periods of activity and quiescence. The study of this duty cycle has recently gained new relevance because of ...the importance of AGN feedback for galaxy evolution. Aims. In this work we investigate the duty cycle of the radio galaxy B2 0258+35, which was previously suggested to be a restarted radio galaxy based on its morphology. The radio source consists of a pair of kpc-scale jets embedded in two large-scale lobes (∼240 kpc) with relaxed shape and very low surface brightness, which resemble remnants of a past AGN activity. Methods. We have combined new LOFAR data at 145 MHz and new Sardinia Radio Telescope data at 6600 MHz with available WSRT data at 1400 MHz to investigate the spectral properties of the outer lobes and derive their age. Results. Interestingly, the spectrum of both the outer northern and southern lobes is not ultra-steep as expected for an old ageing plasma with spectral index values equal to α1451400 = 0.48 ± 0.11 α 1400 145 = 0.48 ± 0.11 ${\rm {\alpha}}_{1400}^{145} = 0.48 \pm 0.11$ and α14006600 = 0.69 ± 0.20 α 6600 1400 = 0.69 ± 0.20 ${\rm {\alpha}}_{6600}^{1400} {=} 0.69\pm0.20$ in the outer northern lobe, and α1451400 = 0.73 ± 0.07 α 1400 145 = 0.73 ± 0.07 ${\rm {\alpha}}_{1400}^{145} {=} 0.73\pm0.07$ in the outer southern lobe. Moreover, despite the wide frequency coverage available for the outer northern lobe (145–6600 MHz), we do not identify a significant spectral curvature (SPC ≃ 0.2 ± 0.2). Conclusions. While mechanisms such as in-situ particle reacceleration, mixing or compression can temporarily play a role in preventing the spectrum from steepening, in no case seem the outer lobes to be compatible with being very old remnants of past activity as previously suggested (with age ≳ 80 Myr). We conclude that either the large-scale lobes are still fuelled by the nuclear engine or the jets have switched off no more than a few tens of Myr ago, allowing us to observe both the inner and outer structure simultaneously. Our study shows the importance of combining morphological and spectral properties to reliably classify the evolutionary stage of low surface brightness, diffuse emission that low frequency observations are revealing around a growing number of radio sources.
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FMFMET, NUK, UL, UM, UPUK
Honeycomb structures are frequently used as energy absorption devices in the automotive and aerospace industry. Many studies have been conducted to optimise these structures and improve ...crashworthiness behaviour. This paper attempts to improve the crashworthiness behaviour of a honeycomb crash box by filling the cells with open-cell aluminium foams. Experimental tests were conducted to develop the honeycomb and aluminium foam material model and, also, to validate the finite element model by experimental data. The finite element model was developed in ABAQUS, and different variables were parameterised to aim a quick implementation. The empty aluminium honeycomb crash box is used as a term of comparison with the foam-filled ones. Foam-filling the crash box allows the control of the densification zone for different impact energies using open-cell aluminium foam, which shows the main novelty of this research. In the end, the optimised structure is presented concerning the optimum number of foam-filled cells and, also, to the aluminium foam’s density that best fits this application.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
We report the detection of diffuse radio emission which might be connected to a large-scale filament of the cosmic web covering a 8° × 8° area in the sky, likely associated with a z ≈ 0.1 overdensity ...traced by nine massive galaxy clusters. In this work, we present radio observations of this region taken with the Sardinia Radio Telescope. Two of the clusters in the field host a powerful radio halo sustained by violent ongoing mergers and provide direct proof of intracluster magnetic fields. In order to investigate the presence of large-scale diffuse radio synchrotron emission in and beyond the galaxy clusters in this complex system, we combined the data taken at 1.4 GHz with the Sardinia Radio Telescope with higher resolution data taken with the NRAO VLA Sky Survey. We found 28 candidate new sources with a size larger and X-ray emission fainter than known diffuse large-scale synchrotron cluster sources for a given radio power. This new population is potentially the tip of the iceberg of a class of diffuse large-scale synchrotron sources associated with the filaments of the cosmic web. In addition, we found in the field a candidate new giant radio galaxy.
Two different approaches to characterize the torque and radial force production in a bearingless multisector permanent magnet machine are presented in this paper. The first method consists of ...modeling the motor in terms of torque and force production as a function of the stationary reference frame <inline-formula><tex-math notation="LaTeX"> \alpha \hbox{--}\beta</tex-math></inline-formula> currents. The current control reference signals are then evaluated adopting the Joule losses minimization as constrain by means of the pseudoinverse matrix. The second method is based on the control of the magnetic field harmonics in the airgap through the current space vector (SV) technique. Once the magnetic field harmonics involved in the torque and force production are determined, the SV transformation can be defined to obtain the reference current SVs. The methods are validated by numerical simulations, finite-element analysis, and experimental tests. The differences in terms of two degrees of freedom levitation performance and efficiency are highlighted in order to give the reader an in-depth comparison of the two methods.
Purpose
The finding of mTOR overactivation in patients affected by pancreatic neuroendocrine tumors (Pa-NETs) led to their treatment with the mTOR inhibitor everolimus. Unfortunately, the efficacy of ...everolimus is restricted by the occurrence of resistance. The mechanisms leading to Pa-NETs’ progression and resistance are not well understood. Notably, chronic inflammation is implicated in NET development. NF-kB is involved in inflammation and drug resistance mechanisms through the activation of several mediators, including STAT3. In this respect, NF-κB and STAT3 interaction is implicated in the crosstalk between inflammatory and tumor cells.
Methods
We investigated the expression of NF-kB in different Pa-NETs by RT-qPCR and immunohistochemistry. Then, we studied the role of NF-κB and STAT3 interplay in QGP-1 cells. Subsequently, we assessed the impact of NF-κB and STAT3 inhibitors in QGP-1 cell proliferation and spheroids growth. Finally, we evaluated the implication of the NF-kB pathway in everolimus-resistant Pa-NET cells.
Results
We found that the increased NF-kB expression correlates with a higher grade in Pa-NETs. The activation of the STAT3 pathway induced by TNFα is mediated by NF-kB p65. NF-kB p65 and STAT3 inhibitors decrease QGP-1 viability, spheroids growth, and Pa-NETs cell proliferation. These effects are maintained in everolimus-resistant QGP-1R cells. Interestingly, we found that NF-kB, STAT3, IL-8, and SOCS3 are overexpressed in QGP-1R compared to QGP-1.
Conclusion
Since the NF-kB pathway is implicated in Pa-NETs’ progression and resistance to everolimus, these data could explain the potential use of NF-kB as a novel therapeutic target in Pa-NET patients.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
BACKGROUND
Important causes of endogenous hyperinsulinaemic hypoglycaemia (EHH) in adult patients are insulinoma and adult nesidioblastosis. Data on main symptoms in EHH are scarce and controversial. ...We analysed main symptoms of patients with EHH in the framework of two prospective studies investigating glucagon-like peptide-1 receptor imaging.
METHODS
Patients were referred from secondary European endocrine centres and endocrinologists. Inclusion criteria were biochemically proven EHH (glucose <2.5 mmol/l in the presence of inadequate insulin and C-peptide levels) with neurological hypoglycaemic symptoms. Demographic characteristics and aetiologies of the patients with EHH were retrieved. Main symptoms were categorised into neurological, sympathicoadrenal (sweating, tremor, palpitation, hunger, shivering and pallor) and nonspecific other symptoms (nonspecific asthenia, weight gain, gastrointestinal symptoms and headaches). Neurological symptoms were subdivided into moderately impaired consciousness (confusion, dizziness, somnolence and delirium), visual, speech and sensorimotor impairment, severely impaired consciousness (loss of consciousness and apathy), attention deficit, seizures and personality changes. Biochemical assessment and duration of EHH at the end of a fasting test were recorded.
RESULTS
Fifty-four patients with full documentation were included in the analysis (74% female; mean age 54 years, range 22–84). Median duration from onset of symptoms to diagnosis of EHH was 12 months (range 0–120). Fifty (92.6%) patients had neurological symptoms, including moderately impaired consciousness (46.3%), visual, speech and sensorimotor function impairment (44.4%), severely impaired consciousness (37%), attention deficit (31.5%), seizures (16.7%) and personality change (13%). Sympathicoadrenal symptoms were present in 33 (61.1%) patients. Nonspecific other symptoms occurred in 36 (66.7%) patients. 43 patients (79.6%) suffered from symptoms of at least two different categories.
CONCLUSIONS
Clinical symptoms of EHH are characterised by a wide variety of mainly different neurological symptoms (“neurological chameleon”). EHH should be considered as a differential diagnosis in many neurological disorders.
Trial registration numbers
NCT00937079 & NCT02127541
Liver transplant (LT) patients need regular follow-up both by ultrasonography and elastography. Shear wave elastography is now available in high-end ultrasound systems that, however, may yield ...different values for any given liver, reflecting technological differences. The aim of this study was to establish whether the point shear wave elastography QElaXto® (QEpSWE), available on Esaote (Genoa, Italy) systems, is comparable to the standard Fibroscan® (vibration-controlled transient elastography, VCTE) in the real-life setting of liver transplant (LT) patients.
We prospectively examined with QEpSWE 196 consecutive LT patients referred for VCTE and ultrasound examination. The agreement between QEpSWE and VCTE was assessed with Lin concordance correlation coefficient (CCC) and Bland-Altman analysis. The performance of QEpSWE was assessed with the ROC curves using the VCTE cut-offs of 7 and 12 kPa for F2-F3 and F4, respectively.
The two methods showed 100% of successful and reliable liver stiffness measurements (LSM), similar median LSM in the whole group and in the two subgroups F2-F3 and F4 of fibrosis, with a disagreement in categorization of liver fibrosis in only 2% of cases, and never more than 1 stage of fibrosis. Further, they presented the same degree of higher LSMs in clinically unstable LT patients and an excellent overall agreement (CCC=0.91, accuracy=0.95, precision=0.96), even if agreement was less satisfactory in the range of severe fibrosis. The optimal cutoffs of QEpSWE were 6.7 and 11.6 kPa for F2-F3 and F4, respectively.
The values of VCTE and QEpSWE showed a very high correlation in the staging of liver fibrosis. QEpSWE seems a promising method for staging liver fibrosis in LT patients.
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