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Background: Propofol is associated with pain during injection, which is stressful to patients. The present study was designed to investigate the analgesic effect of pretreatment with remifentanil and esmolol in minimizing propofol injection pain, compared with placebo.Methods: In a randomized, double-blind, prospective trial, 120 patients, scheduled for elective dental surgery under general anesthesia, were randomized to 1 of the 4 treatment arms (n = 30 each) receiving normal saline, remifentanil 0.35 mg/kg, esmolol 0.5 mg/kg, and 1 mg/kg before administration of propofol. During injection of 1% propofol 0.5 mg/kg, pain was evaluated by a 4-point score (0 = none, 1 = mild, 2 = moderate, 3 = severe). Any adverse effects such as hypotension and bradycardia were recorded during the perioperative periods.Results: In all, 120 patients completed this study. There were no significant differences in terms of demographic data. The incidence of pain on injection of propofol was 11 (36.7%) with remifentanil 0.35 mg/kg, 12 (40%) with esmolol 0.5 mg/kg, and 11 (36.7%) with esmolol 1 mg/kg, compared with 25 (83.3%) with normal saline (respectively, P < 0.05). There were no significant differences in the incidence of pain between groups with remifentanil 0.35 mg/kg, and esmolol 0.5 mg/kg and 1 mg/kg. There were no emergence reactions such as hypotension and bradycardia in all groups.Conclusions: Pretreatment with esmolol 0.5 mg/kg and 1 mg/kg and remifentanil 0.35 mg/kg equally decreased pain during propofol injection.Abbreviations: LCT = long-chain triglyceride, MCT = medium-chain triglyceride, NMDA = N-methyl-d-aspartate.

This paper introduces biocarbon, referred to as biochar, as a novel eco‐friendly and cost‐effective additive to increase interactions among bitumen components while facilitating carbon management in roadway infrastructures. It is hypothesized that functional groups on biochar surfaces enhance interactions between biochar and bitumen constituents. This in turn enhances mechanical properties and durability of asphalt pavements. This study uses biochars derived from six different types of woody biomass and one type of algae, and polyethylene terephthalate granules as a carrier to introduce biochar to bitumen. Quantum‐based molecular modeling and noncovalent interaction analysis show that algal biochar interacts more effectively with bitumen components. The enhanced interaction of algal biochar is attributed to its surface functional groups including reactive nitrogen‐ and oxygen‐carrying functional groups. The rheological characterization of bitumen doped with different biochars confirms that the lowest separation index occurs for bitumen containing algal biochar, which also exhibits the highest percent of elastic recovery and resistance to permanent deformation. The study suggests that asphalt pavement durability can be enhanced by selection of the proper biochar to increase intermolecular interactions. Promising results for the algae biochar promote its use in carbon management for roadway infrastructure by sequestering CO2 from air through photosynthesis of algae biomass.

Background Sub-umbilical surgery under caudal block in conjunction with sevoflurane sedation may be safe in terms of maintaining spontaneous breathing and avoiding complications associated with general anesthesia. However, sevoflurane-induced emergence agitation (EA) continues to be a clinically important phenomenon in children. To compare the incidence of EA in children undergoing sub-umbilical surgery under caudal block with two different doses of sevoflurane. Methods Forty children (aged 1–5 years) scheduled to undergo inguinal hernia repair under caudal block with sevoflurane sedation via a face mask were randomized into either the low-dose (1.0%) end-tidal sevoflurane concentration group (Group LS) or the high-dose (2.5%) end-tidal sevoflurane concentration group (Group HS). We monitored EA episodes at 5 and 30 min in the post-anesthetic care unit (PACU) by using the fourpoint agitation scale and the Pediatric Anesthesia Emergence Delirium (PAED) scale. Results The four-point agitation scale scores and PAED scores were not different between the groups at 5 min. However, the agitation score was higher in Group HS than in Group LS at 30 min after arriving in the PACU. The time required to recover from sedation was longer in Group HS than in Group LS. Conclusions Face-mask sedation with 1.0% sevoflurane in conjunction with caudal block may be more effective than that with 2.5% sevoflurane in preventing EA.

In this paper, a charge equalization converter using a multi-winding transformer is proposed. The proposed scheme achieves the cell-to-cell charge transportation by buck-boost and flyback operation. In this operation, adjacent two cells share a current path or secondary tap of multi-winding transformer. Therefore, the number of windings cuts in half in comparison to conventional multi-winding charge equalization converter, resulting small circuit size. To verify the operation of the proposed charge equalization converter, experiment for lithium-ion battery stack is performed. Index Terms--battery equalizer, Multi-winding Transformer