Design of a Power-Dense Aviation Motor With a Low-Loss Superconducting Slotted Armature

This article describes the design and analysis of a 2.5-MW, 5000-rpm electric motor with a slotted armature employing REBCO high-temperature superconductors (HTS). The alternating current and field in the armature induces AC losses in the superconductors, requiring cryogenic cooling. Therefore, the aim is to design a machine with sufficiently low losses to make this cooling realistic, which simultaneously outperforms the state-of-the-art. The reasoning behind the key design choices is presented before the model used for two-dimensional (2-D) finite element analysis (FEA) is described. Then, HTS AC losses are studied with the T-A-formulation, examining the impact of various operating conditions. Aligning the HTS tapes with the field was found to successfully reduce AC losses, while filamentization was only successful for more than 10 filaments. The final design had an active torque density of 50.9 Nm/kg and an estimated efficiency of 99.8% when the HTS are operated at 40 K.Design of a Power-Dense Aviation Motor With a Low-Loss Superconducting Slotted ArmaturepublishedVersio

Intranasal analgesia for acute moderate to severe pain in children – a systematic review and meta-analysis

Abstract Background Children in acute pain often receive inadequate pain relief, partly from difficulties administering injectable analgesics. A rapid-acting, intranasal (IN) analgesic may be an alternative to other parenteral routes of administration. Our review compares the efficacy, safety, and acceptability of intranasal analgesia to intravenous (IV) and intramuscular (IM) administration; and to compare different intranasal agents. Methods We searched Cochrane Library, MEDLINE/PubMed, Embase, Web of Knowledge, Clinicaltrials.gov, Controlled-trials.com/mrcr, Clinicaltrialsregister.eu, Apps.who.int/trialsearch. We also screened reference lists of included trials and relevant systematic reviews. Studies in English from any year were included. Two authors independently assessed all studies. We included randomised trials (RCTs) of children 0–16, with moderate to severe pain; comparing intranasal analgesia to intravenous or intramuscular analgesia, or to other intranasal agents. We excluded studies of procedural sedation or analgesia. We extracted study characteristics and outcome data and assessed risk of bias with the ROB 2.0-tool. We conducted meta-analysis and narrative review, evaluating the certainty of evidence using GRADE. Outcomes included pain reduction, adverse events, acceptability, rescue medication, ease of and time to administration. Results We included 12 RCTs with a total of 1163 children aged 3 to 20, most below 10 years old, with a variety of conditions. Our review shows that: - There may be little or no difference in pain relief (single dose IN vs IV fentanyl MD 4 mm, 95% CI -8 to 16 at 30 min by 100 mm VAS; multiple doses IN vs IV fentanyl MD 0, 95%CI -0.35 to 0.35 at 15 min by Hannallah score; single dose IN vs IV ketorolac MD 0.8, 95% CI -0.4 to 1.9 by Faces Pain Scale-Revised), adverse events (single dose IN vs IV fentanyl RR 3.09, 95% CI 0.34 to 28.28; multiple doses IN vs IV fentanyl RR 1.50, 95%CI 0.29 to 7.81); single dose IN vs IV ketorolac RR 0.716, 95% CI 0.23 to 2.26), or acceptability (single dose IN vs IV ketorolac RR 0.83, 95% CI 0.66 to 1.04) between intranasal and intravenous analgesia (low certainty evidence). - Intranasal diamorphine or fentanyl probably give similar pain relief to intramuscular morphine (narrative review), and are probably more acceptable (RR 1.60, 95% CI 1.42 to 1.81) and tolerated better (RR 0.061, 95% CI 0.03 to 0.13 for uncooperative/negative reaction) (moderate certainty); adverse events may be similar (narrative review) (low certainty). - Intranasal ketamine gives similar pain relief to intranasal fentanyl (SMD 0.05, 95% CI -0.20 to 0.29 at 30 min), while having a higher risk of light sedation (RR 1.74, 95% CI 1.30 to 2.35) and mild side effects (RR 2.16, 95% CI 1.72 to 2.71) (high certainty). Need for rescue analgesia is probably similar (RR 0.85, 95% CI 0.62 to 1.17) (moderate certainty), and acceptability may be similar (RR 1.15, 95% CI 0.89 to 1.48) (low certainty). Conclusions Our review suggests that intranasal analgesics are probably a good alternative to intramuscular analgesics in children with acute moderate to severe pain; and may be an alternative to intravenous administration. Intranasal ketamine gives similar pain relief to fentanyl, but causes more sedation, which should inform the choice of intranasal agent

Additional file 6 of Intranasal analgesia for acute moderate to severe pain in children – a systematic review and meta-analysis

Additional file 6. Meta-analyses for other rescue medication

Additional file 9 of Intranasal analgesia for acute moderate to severe pain in children – a systematic review and meta-analysis

Additional file 9. Meta-analysis for adverse events – INK vs INF, specific events

Additional file 4 of Intranasal analgesia for acute moderate to severe pain in children – a systematic review and meta-analysis

Additional file 4. Funnel plot – Pain – INK vs INF

Additional file 5 of Intranasal analgesia for acute moderate to severe pain in children – a systematic review and meta-analysis

Additional file 5. Ongoing and/or unfinished studies

Additional file 11 of Intranasal analgesia for acute moderate to severe pain in children – a systematic review and meta-analysis

Additional file 11. Departures from protocol

Additional file 1 of Intranasal analgesia for acute moderate to severe pain in children – a systematic review and meta-analysis

Additional file1. Search strategy

Additional file 10 of Intranasal analgesia for acute moderate to severe pain in children – a systematic review and meta-analysis

Additional file 10. Meta-analysis for sedation – INK vs INF

Additional file 2 of Intranasal analgesia for acute moderate to severe pain in children – a systematic review and meta-analysis

Additional file 2. Sensitivity analysis – Pain – INK vs INF