793 research outputs found
Fast Acceleration of Transrelativistic Electrons in Astrophysical Turbulence
Highly energetic, relativistic electrons are commonly present in many
astrophysical systems, from solar flares to the intra-cluster medium, as
indicated by observed electromagnetic radiation. However, open questions remain
about the mechanisms responsible for their acceleration, and possible
re-acceleration. Ubiquitous plasma turbulence is one of the possible universal
mechanisms. We study the energization of transrelativistic electrons in
turbulence using hybrid particle-in-cell, which provide a realistic model of
Alfv\'{e}nic turbulence from MHD to sub-ion scales, and test particle
simulations for electrons. We find that, depending on the electron initial
energy and turbulence strength, electrons may undergo a fast and efficient
phase of energization due to the magnetic curvature drift during the time they
are trapped in dynamic magnetic structures. In addition, electrons are
accelerated stochastically which is a slower process that yields lower maximum
energies. The combined effect of these two processes determines the overall
electron acceleration. With appropriate turbulence parameters, we find that
superthermal electrons can be accelerated up to relativistic energies. For
example, with heliospheric parameters and a relatively high turbulence level,
rapid energization to MeV energies is possible.Comment: Accepted for publication in The Astrophysical Journa
Thoracic epidural anaesthesia vs intrathecal morphine in dogs undergoing major thoracic and abdominal surgery: clinical study
A comparison of 0.375% ropivacaine psoas compartment block and 2% prilocaine spinal anaesthesia in dogs undergoing tibial plateau levelling osteotomy
BACKGROUND: In dogs undergoing routine elective orthopaedic surgeries carried out as same-day surgeries regional anaesthetic techniques (RATs) should aim to produce analgesia but minimising the postoperative motor dysfunction. Our objective was to compare the perioperative analgesic effects and the time to motor recovery between spinal anaesthesia (SA) with hyperbaric solution of prilocaine 2% (mg = 4 x [0.3 × BW (kg) + 0.05 × SCL (cm)]) and morphine (0.03 mg/kg) and combined ultrasound (US) and electro stimulator-guided psoas compartment and ischiatic nerve block (PB) with ropivacaine 0.375% (0.45 mL/kg). Dogs undergoing tibial plateau levelling osteotomy (TPLO) were randomly assigned to receive either SA or PB. Procedural failure, perioperative rescue analgesia, motor block recovery and complications were recorded. RESULTS: Procedural failure rate (PFR) was 19% (7 out of 36) for SA and 9% (3 out of 32) for PB (p = 0.31). Intraoperative rescue analgesia was administered to 6/29 (21%) SA group dogs and in 15/29 (52%) PB group dogs, respectively (p = 0.03). At 3 h after RAT, percentage of dogs with complete block recovery was 25/29 (86%) and 25/29 (86%) in group SA and PB, respectively (p = 1). Two cases of pruritus and one case of urinary retention were recorded in the SA group. Residual ischiatic nerve block was noted at 12 h after RAT in 2/15 (13%) of dogs in group PB; it completely resolved 24 h after RAT. CONCLUSIONS: SA with prilocaine 2% and PB with ropivacaine 0.37% were found suitable for dogs undergoing same-day TPLO surgery. Pruritus and urinary retention in SA and residual block in both groups might occasionally delay the time of discharge. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s12917-022-03277-6
Natural Formulations Based on Olea europaea L. Fruit Extract for the Topical Treatment of HSV-1 Infections
In the present study, a hydroxytyrosol-rich Olea europaea L. fruit extract (OFE) was added to three thoroughly green formulations—hydrogel, oleogel, and cream—in order to evaluate their antiviral activity against HSV-1. The extract was characterized by different analytical techniques, i.e., FT-IR, XPS, and TGA. HPLC analyses were carried out to monitor the content and release of hydroxytyrosol in the prepared formulations. The total polyphenol content and antioxidant activity were investigated through Folin–Ciocâlteu’s reagent, DPPH, and ABTS assays. The ability of the three formulations to convey active principles to the skin was evaluated using a Franz cell, showing that the number of permeated polyphenols in the hydrogel (272.1 ± 1.8 GAE/g) was significantly higher than those in the oleogel and cream (174 ± 10 and 179.6 ± 2 GAE/g, respectively), even if a negligible amount of hydroxytyrosol crossed the membrane for all the formulations. The cell viability assay indicated that the OFE and the three formulations were not toxic to cultured Vero cells. The antiviral activity tests highlighted that the OFE had a strong inhibitory effect against HSV-1 with a 50% inhibitory concentration (IC50) at 25 µg/mL, interfering directly with the viral particles. Among the three formulations, the hydrogel exhibited the highest antiviral activity also against the acyclovir-resistant strain
Application of the Maximum Power Extrapolation Procedure for Human Exposure Assessment to 5G Millimeter Waves: Challenges and Possible Solutions
Application of the Maximum Power Extrapolation Procedure for Human Exposure Assessment to 5G Millimeter Waves: Challenges and Possible Solutions
This paper describes an investigation on the application of the Maximum Power Extrapolation (MPE) technique on a fully operational Fixed Wireless Access (FWA) FR2-band 5G gNB. The data was acquired in [27.1-27.3] GHz band using a network scanner over nearly 10 minutes periods to allow a statistical analysis and an accurate estimation of the role of each contribution to the total uncertainty, including the fading affecting the 5G FR2 reference signal. The results show that the level of the electromagnetic field is well below the limits imposed by Italian legislation. However the goal of the paper is more fundamental, and shows an approach that can be used to identify the critical elements of the measurement set-up, suggesting where to concentrate efforts to improve the measurement procedure. In particular, the uncertainty budget highlights three contributions, (i.e. estimation of the traffic beam level, of the probe response and of the 5G FR2 reference signal) that deserve further investigations
Massive measurements of 5G exposure in a town: methodology and results
We target the problem of performing a large set of measurements over the territory to characterize the exposure from a 5G deployment. Since using a single Spectrum Analyzer (SA) is not practically feasible (due to the limited battery duration), in this work we adopt an integrated approach, based on the massive measurement of 5G metrics with a 5G smartphone, followed by a detailed analysis done with the SA and an ElectroMagnetic Field (EMF) meter in selected locations. Results, obtained over a real territory covered by 5G signal, reveal that 5G exposure is overall very limited for most of measurement locations, both in terms of field strength (up to 0.7 [V/m]) and as share w.r.t. other wireless technologies (typically lower than 15%). Moreover, our approach allows easily spotting measurement outliers, e.g., due to the exploitation of Dynamic Spectrum Sharing (DSS) techniques between 4G and 5G. In addition, the exposure metrics collected with the smartphone are overall a good proxy of the total exposure measured over the whole 5G channel. Moreover, the sight conditions and the distance from 5G base station play a great role in determining the level of exposure. Finally, a maximum of 130 [W] of power radiated by a 5G base station is estimated in the scenario under consideration
Experimental investigation in controlled conditions of the impact of dynamic spectrum sharing on maximum-power extrapolation techniques for the assessment of human exposure to electromagnetic fields generated by 5G gNodeB
Experimental investigation in controlled conditions of the impact of dynamic spectrum sharing on maximum-power extrapolation techniques for the assessment of human exposure to electromagnetic fields generated by 5G gNodeB
Effect of pasture in oak and chestnut groves on chemical and sensorial traits of cured lard of Cinta Senese pigs
The objective of this study was to evaluate the effect of pasture in oak and chestnut groves on the chemical and sensorial traits of cured lard. Thirty Cinta Senese barrows (124kg of l.w. on average) were allotted to three groups: one group (CONC) was reared outdoors in a confined area and fed commercial feedstuff. The other two groups were raised under free-range conditions on acorns (AC) or chestnuts (CH). At slaughtering (148kg of LW) the backfat was seasoned for 60 days to obtained cured lard. Results demonstrated that the lard of CH and AC respect to CONC group was the richest in MUFA (46.9 and 47.76 vs 44.78% respectively) because of the higher content of oleic acid (44.2 and 44.91 vs 42.05%, P<0.05, respectively). CH showed a higher percentage of PUFA-n3 than AC and CONC (1.18 vs 1.06 and 1.03%, P<0.05, respectively), a lower content of α-tocopherol (9.77 vs 14.46 and 13.31μ/g, P<0.05 respectively) and a higher content of γ-tocopherol (13.73 vs 6.02 and 4.32μ/g, P<0.05, respectively). As regards sensorial traits, the lard of CH and AC groups exhibited a lower value of pinkness than CONC (29.3 and 32.4 vs 49.2, P<0.05, respectively) and higher scores of yellowness (31.4 and 28.6 vs 18.6, P<0.05, respectively) and oiliness (37.0 and 33.7 vs 24.0, P<0.05, respectively). The pasture in the acorn and chestnut groves affected the chemical traits of lard, prevalently the composition of fatty acids . The consumption of acorns or chestnuts led to a higher content of oleic acid with respect to concentrate, affecting some sensorial traits of lard
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