Harvesting mechanical energy is an important route in obtaining cost-effective, clean and sustainable electric energy. Here we report a two-dimensional planar-structured triboelectric generator on the basis of contact electrification. The radial arrays of micro-sized sectors on the contact surfaces enable a high output power of 1.5 W (area power density of 19 mW cm À 2 ) at an efficiency of 24%. The triboelectric generator can effectively harness various ambient motions, including light wind, tap water flow and normal body movement. Through a power management circuit, a triboelectric-generator-based power-supplying system can provide a constant direct-current source for sustainably driving and charging commercial electronics, immediately demonstrating the feasibility of the triboelectric generator as a practical power source. Given exceptional power density, extremely low cost and unique applicability resulting from distinctive mechanism and structure, the triboelectric generator can be applied not only to self-powered electronics but also possibly to power generation at a large scale.

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BackgroundTo determine whether continuous intravenous infusion of dexmedetomidine (DEX) can affect the incidence of Emergence Agitation (EA) after general anesthesia in infant undergoing cleft palate repair surgery.MethodsForty infants underwent cleft palate repair surgery under general anesthesia were randomly divided into the DEX (D) group and Placebo (P) groups. Patients in group D received continuous intravenous infusion of DEX 0.8 μg · kg-1 · min-1 after the induction. Patients in group P were administered with continuous intravenous infusion of the equivalent volume of normal saline. Both groups were induced with fentanyl 0.005 mg/Kg, propofol 2 mg/Kg and cisatracurium 0.2 mg/Kg. Anaesthesia was maintained with continuous intravenous infusion of propofol (2 mg/Kg · h), remifentanil (0.1 μg/Kg · h), and inhalation of 1 to 3 % sevoflurane.ResultThe heart rate (HR) in group P was significant higher than that in group D at the time of operation (P < 0.05), postoperative 15 min, 30 min and the time of extubation (P < 0.01). The mean arterial pressure (MAP) in group P was higher comparing with MAP in group D at the time of extubation (P < 0.05). The spontaneous eye opening times and spontaneous arm or leg motion times were longer in group D (P < 0.05). The mean agitation scores of patients in group D were significantly lower than that in group P (P < 0.01). However, the incidence of EA in group P and group D was 90 % and 15 % (P <0.05).ConclusionThe continuous intravenous infusion of DEX after induction could significantly reduce the occurrence of EA.Trial registrationThe Chinese Clinical Trial Register ChiCTR-TRC-13003865

The aim of this study was to investigate the effects of different general anaesthesia techniques on immune responses in patients undergoing surgery for tongue cancer. Sixty American Society of Anesthesiologists physical status 1 or 2 patients undergoing elective reconstructive surgery for tongue cancer were randomised to three groups. Group 1 received propofol induction and maintenance (TIVA), group 2 received propofol induction and sevoflurane maintenance (MIXED) and group 3 received sevoflurane induction and maintenance (SEVO). All patients received an infusion of remifentanil. Blood samples were obtained at eight time-points: 30 minutes before induction (T 0); one hour (T 1), three hours (T 2) and five hours (T 3) after induction; at the end of the operation (T 4); and 24 hours (T 5), 48 hours (T 6) and 72 hours (T 7) after operation. The T lymphocyte subsets (including CD3 + cells, CD3 + CD4 + cells and CD3 + CD8 + cells) and CD4 + /CD8 + ratio, natural killer cells and B lymphocytes were analysed by flow cytometry. All immunological indicators except CD3 + CD8 + cells were significantly decreased in all groups at T 1~T5 compared to T 0 (P <0.05). The percentages of CD3 + cells, CD3 + / CD4 + cells and natural killer cells, and the CD4 + /CD8 + ratios were significantly lower in the MIXED groups and SEVO groups but not the TIVA group at T 6 as compared with T 0 (P <0.05). There were minor but statistically significant differences in the percentages of CD3 + cells, CD3 + CD4 + cells and natural killer cells, and the CD4 + / CD8 + ratios between the SEVO group and the TIVA group at T 2~T6 (P <0.05). These findings suggest that propofol has slightly less effect on cellular immune responses than sevoflurane.

In a cold atomic ensemble the weak Raman scattering of an incident laser beam writes a spin-wave grating by transferring an atom between ground-level hyperfine states. These spin-waves serve as a basis for a quantum memory. For clock states, where magnetic dephasing is suppressed, thermal motion of the atoms across the spin-wave is the principal source of dephasing on the sub-millisecond timescale, limiting the quantum memory time achievable. An investigation of the role of the optical lattice in reducing motional dephasing is presented, using Monte Carlo simulations to study the influence of ensemble temperature, trap depth and differential ac Stark shifts in the case of rubidium.

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Purpose: This study aimed to evaluate the suppressive effects of a small dose of butorphanol on sufentanil-induced cough during general anesthesia induction. Methods: 120 patients who were scheduled for elective maxillofacial surgery of American Society of Anesthesiologists I∼II, aged 18∼65 years were randomly divided into 3 groups (n = 40). Patients received butorphanol 0.1 mg (group I), 1 mg (group II) or an equal volume of 0.9% normal saline (group III) 5 seconds right before sufentanil bolus (0.5ug/kg). Sufentanil was diluted into 5ug/mL and administrated within 5 seconds. The incidence and reflex degree of cough in all groups were evaluated within 2 minutes after the injection of sufentanil during anesthesia induction. Mean arterial pressure (MAP) and heart rate (HR) were recorded at T0 (before the injection of butorphanol or normal saline), T1 (before the injection of sufentanil) and T2 (2 minutes after sufentanil injection). Results: The HR and MAP values were no significant difference among the 3 groups at the same observation point. In group II, the HR decreased significantly at T2 compared with T0 and T1 (P <0.05, T2 VS T0, T1). None of the patients in group I and group II had cough, and 33 patients in group III developed cough, of which 12.5% were mild, 40% were moderate, and 30% were severe. Conclusions: The results of present study suggest that a small dose of butorphanol 0.1 mg can prevent sufentanil-induced cough and ensure a relatively stable hemodynamic state during general anesthesia induction.