Numerical optimization for vibration and noise of the wheel based on PSO-GA method

Currently, those reported researches conducted optimal design for the wheel only in order to reduce the tread wear and increase the service life, but they did not consider the wheel vibration and radiation noise which seriously influence people’s life and did not achieve obvious noise reduction effects. Aiming at this question, a multi-body dynamic model of the high-speed train was established, and the vertical and radial force was extracted to input into the finite element model of the wheel to compute its vibration characteristics. Then, the wheel was conducted on a multi-objective optimization based on particle swarm optimization improved by genetic algorithm (PSO-GA) method. Finally, the optimized vibration results were mapped to the acoustic element model to compute the radiation noise of the wheel. The computational model was also validated by experimental test. In order to observe the optimized effect, the optimized results were compared with those of the traditional GA and PSO method. Solutions of the traditional GA and PSO method were relatively dispersed during iterations and the algorithm could easily fall into the locally optimal solution. The optimized results of PSO-GA method were obviously better. Compared with the original wheel, the vibration acceleration was reduced by 22.9 %, and the mass was reduced by 1.1 %. Finally, the optimized vibration was mapped to the boundary element model to compute the radiation noise of the wheel, and the computational results were compared with the original wheel. Radiation noises of the original wheel were obviously more than that of the optimized wheel, and there were a lot of obvious peak noises in the original wheel. Radiation noises of the optimized wheel only had two obvious noise peaks in the analyzed frequency. Therefore, a wheel with low noises and lightweight was achieved in this paper

Prevention and Treatment of Cardiac Surgery Associated Acute Kidney Injury.

AIM OF REVIEW: Acute kidney injury (AKI) after cardiac surgery is a relatively common postoperative complication and is independently related to increased mortality and morbidity. METHOD: In this review, we will focus on risk factors of developing AKI, early detection by biomarkers and preventive strategies for AKI after adult cardiac surgery. RECENT FINDINGS: Many perioperative factors affect renal function and acute AKI following cardiac surgery. Novel biomarkers of kidney injury such as neutrophil gelatinase-associated lipocalin (NGAL), interleukin-18 (IL-18), cystatin C (CysC), have the potential to facilitate the early diagnosis of cardiac surgery associated AKI (CSA-AKI). Pharmacological interventions have been inconsistent to their efficacy, and to date, there is no compelling pharmacologic agent known to reduce the risk of AKI or treat established AKI. SUMMARY: Preventive strategies of AKI focus on optimal perioperative management

Premedication with dexmedetomidine in pediatric patients: a systematic review and meta-analysis

Premedication is important in pediatric anesthesia. This meta-analysis aimed to investigate the role of dexmedetomidine as a premedicant for pediatric patients. A systematic literature search was conducted to identify randomized controlled trials comparing dexmedetomidine premedication with midazolam or ketamine premedication or placebo in children. Two reviewers independently performed the study selection, quality assessment and data extraction. The original data were pooled for the meta-analysis with Review Manager 5. The main parameters investigated included satisfactory separation from parents, satisfactory mask induction, postoperative rescue analgesia, emergence agitation and postoperative nausea and vomiting. Thirteen randomized controlled trials involving 1190 patients were included. When compared with midazolam, premedication with dexmedetomidine resulted in an increase in satisfactory separation from parents (RD = 0.18, 95% CI: 0.06 to 0.30, p = 0.003) and a decrease in the use of postoperative rescue analgesia (RD = -0.19, 95% CI: -0.29 to -0.09, p = 0.0003). Children treated with dexmedetomidine had a lower heart rate before induction. The incidence of satisfactory mask induction, emergence agitation and PONV did not differ between the groups. Dexmedetomidine was superior in providing satisfactory intravenous cannulation compared to placebo. This meta-analysis suggests that dexmedetomidine is superior to midazolam premedication because it resulted in enhanced preoperative sedation and decreased postoperative pain. Additional studies are needed to evaluate the dosing schemes and long-term outcomes of dexmedetomidine premedication in pediatric anesthesia

2-Meth­oxy-N′-(2-methoxy­benzyl­idene)benzohydrazide

The title Schiff base compound, C16H16N2O3, was derived from the condensation of 2-methoxy­benzaldehyde with 2-methoxy­benzohydrazide in an ethanol solution. The dihedral angle between the two aromatic rings is 87.5 (3)°. In the crystal structure, the mol­ecules are linked into chains running parallel to the a axis by inter­molecular N—H⋯O hydrogen bonds

The Online Data Quality Monitoring System at BESIII

The online Data Quality Monitoring (DQM) plays an important role in the data taking process of HEP experiments. BESIII DQM samples data from online data flow, reconstructs them with offline reconstruction software, and automatically analyzes the reconstructed data with user-defined algorithms. The DQM software is a scalable distributed system. The monitored results are gathered and displayed in various formats, which provides the shifter with current run information that can be used to find problems early. This paper gives an overview of DQM system at BESIII.Comment: Already submit to Chinese Physics

Oxycodone vs. sufentanil combined with quadratus lumborum block vs. transverse abdominis plane block in laparoscopic major gastrointestinal surgery: A randomized factorial trial protocol

Background: Multimodal analgesia plays a key role in enhanced recovery after surgery. Herein, we describe a trial protocol investigating the effects of oxycodone-vs. sufentanil-based patient-controlled analgesia in combination with quadratus lumborum block (QLB) vs. transverse abdominis plane block (TAPB) on quality of recovery following major laparoscopic gastrointestinal surgery. Methods: and analysis: This is a prospective, randomized, controlled clinical trial with a 2 × 2 factorial design. A total of 120 adult patients undergoing laparoscopic major gastrointestinal surgery will be randomized, in a 1:1:1:1 ratio, to receive one of two patient-controlled analgesia regimens (based on oxycodone or sufentanil) and one of two regional blocks (QLB or TAPB). The primary outcome measure of this trial is the quality of recovery at 24 h after surgery, assessed using the 15-item quality of recovery (QoR-15) scale. The secondary outcomes include QoR-15 scores at 48 and 72 h after surgery; visceral and incisional pain at rest and while coughing at 1, 6, 24 and 48 h postoperatively; analgesic consumption within 0–24 h and 24–48 h postoperatively; need for rescue analgesia; postoperative flatus time; postoperative adverse events (sedation, nausea and vomiting, use of antiemetics, respiratory depression, and dizziness); and length of postoperative hospital stay. Discussion: The results of this trial will provide evidence for the optimal multimodal analgesic strategy to improve the quality of recovery for patients undergoing laparoscopic major gastrointestinal surgery. Trial registration: This trial was registered at the Chinese Clinical Trial Registry (www.chictr.org.cn, identifier: ChiCTR2400080766)

Dexmedetomidine post-treatment attenuates cardiac ischaemia/reperfusion injury by inhibiting apoptosis through HIF-1α signalling.

Hypoxia-inducible factor 1α (HIF-1α) plays a critical role in the apoptotic process during cardiac ischaemia/reperfusion (I/R) injury. This study aimed to investigate whether post-treatment with dexmedetomidine (DEX) could protect against I/R-induced cardiac apoptosis in vivo and in vitro via regulating HIF-1α signalling pathway. Rat myocardial I/R was induced by occluding the left anterior descending artery for 30 minutes followed by 6-hours reperfusion, and cardiomyocyte hypoxia/reoxygenation (H/R) was induced by oxygen-glucose deprivation for 6 hours followed by 3-hours reoxygenation. Dexmedetomidine administration at the beginning of reperfusion or reoxygenation attenuated I/R-induced myocardial injury or H/R-induced cell death, alleviated mitochondrial dysfunction, reduced the number of apoptotic cardiomyocytes, inhibited the activation of HIF-1α and modulated the expressions of apoptosis-related proteins including BCL-2, BAX, BNIP3, cleaved caspase-3 and cleaved PARP. Conversely, the HIF-1α prolyl hydroxylase-2 inhibitor IOX2 partly blocked DEX-mediated cardioprotection both in vivo and in vitro. Mechanistically, DEX down-regulated HIF-1α expression at the post-transcriptional level and inhibited the transcriptional activation of the target gene BNIP3. Post-treatment with DEX protects against cardiac I/R injury in vivo and H/R injury in vitro. These effects are, at least in part, mediated via the inhibition of cell apoptosis by targeting HIF-1α signalling

Ventricular fibrillation induced by fever in structurally normal hearts

Ventricular fibrillation (VF) is a life-threatening arrhythmia that usually happens in patients with structural heart diseases. However, fever-induced ventricular fibrillation in structurally normal hearts was reported, and the four main diseases associated with these cases were Brugada syndrome, long QT syndrome, idiopathic ventricular fibrillation, and non-cardiovascular diseases. In this review, we analyzed this phenomenon and its clinical characteristics

Responsiveness of stroke volume variation and central venous pressure during acute normovolemic and hypervolemic hemodilution.

BackgroundStroke volume variation (SVV) is a robust indicator of fluid responsiveness during volume change. We compared the sensibility of SVV by Vigileo/Flotrac to central venous pressure (CVP) when volume changes in patients undergoing intraoperative acute normovolemic hemodilution (ANH) and acute hypervolemic hemodilution (AHH).MethodsForty patients were randomly divided into an ANH group (n = 20) and an AHH group (n = 20). All patients received general anesthesia and were mechanically ventilated. Data were collected from 7 different time-points in the ANH group: baseline, after withdrawal of 5%, 10%, and 15% of the estimated blood volume (EBV) and after replacement with an equal volume of 6% hydroxyethyl starch 130/0.4 (HES) in 5% EBV increments to baseline. There were four time points in the AHH group: baseline, after 5%, 10%, and 15% expansion of the EBV with 6% HES. At each time-point, CVP, SVV and other hemodynamic parameters measurements were obtained.ResultsAfter removal of 10% and 15% EBV, SVV significantly increased from 10.9 ± 3.0 to 14.1 ± 3.4 and 10.9 ± 3.0 to 16.0 ± 3.3 (P < 0.01), and returned to a final value of 10.6 ± 3.4 after volume replacement. The CVP value was unchanged after removal and replacement of 15% of the EBV. There were no significant changes in SVV after 5%, 10% whereas there was a significant reduction after 15% (8.2 ± 1.7) expansion of the EBV compared with baseline (9.9 ± 1.8) (P = 0.033). However, there was a significant increase in CVP after 10% (10.3 ± 2.4), 15% (11.3 ± 2.2) expansion of the EBV compared with baseline (8.2 ± 2.7) (P < 0.01).ConclusionSVV is a more sensitive parameter for volume than CVP during hypovolemia, on the contrary CVP is more sensitive than SVV during hypervolemia

Protective efficacy of a broadly cross-reactive swine influenza DNA vaccine encoding M2e, cytotoxic T lymphocyte epitope and consensus H3 hemagglutinin

BACKGROUND: Pigs have been implicated as mixing reservoir for the generation of new pandemic influenza strains, control of swine influenza has both veterinary and public health significance. Unlike human influenza vaccines, strains used for commercially available swine influenza vaccines are not regularly replaced, making the vaccines provide limited protection against antigenically diverse viruses. It is therefore necessary to develop broadly protective swine influenza vaccines that are efficacious to both homologous and heterologous virus infections. In this study, two forms of DNA vaccines were constructed, one was made by fusing M2e to consensus H3HA (MHa), which represents the majority of the HA sequences of H3N2 swine influenza viruses. Another was made by fusing M2e and a conserved CTL epitope (NP147-155) to consensus H3HA (MNHa). Their protective efficacies against homologous and heterologous challenges were tested. RESULTS: BALB/c mice were immunized twice by particle-mediated epidermal delivery (gene gun) with the two DNA vaccines. It was shown that the two vaccines elicited substantial antibody responses, and MNHa induced more significant T cell-mediated immune response than MHa did. Then two H3N2 strains representative of different evolutional and antigenic clusters were used to challenge the vaccine-immunized mice (homosubtypic challenge). Results indicated that both of the DNA vaccines prevented homosubtypic virus infections completely. The vaccines’ heterologous protective efficacies were further tested by challenging with a H1N1 swine influenza virus and a reassortant 2009 pandemic strain. It was found that MNHa reduced the lung viral titers significantly in both challenge groups, histopathological observation showed obvious reduction of lung pathogenesis as compared to MHa and control groups. CONCLUSIONS: The combined utility of the consensus HA and the conserved M2e and CTL epitope can confer complete and partial protection against homologous and heterologous challenges, respectively, in mouse model. This may provide a basis for the development of universal swine influenza vaccines