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The aim of this study was to evaluate the effectiveness of cricoid and paralaryngeal force for oesophageal entrance occlusion during induction of anaesthesia. Seventy-four patients were included in this randomised, crossover study. The relative position of the glottis and outer anteroposterior diameter of the upper oesophageal entrance were assessed at baseline, after the application of 30 N cricoid and paralaryngeal force, and after induction of anaesthesia. The occlusion rate of the oesophageal entrance with cricoid and paralaryngeal force was assessed during direct laryngoscopy. The relative position of the upper oesophageal entrance to the glottis changed in 45 out of 74 patients after induction of anaesthesia and during direct laryngoscopy compared with the awake state. The application of cricoid and paralaryngeal force decreased the mean (SD) diameter of the upper oesophageal entrance to a similar degree in awake (8.5 (2.1) mm to 6.4 (1.7) mm and 6.5 (1.6) mm, respectively; p < 0.001) and anaesthetised (8.7 (2.2) mm to 6.5 (1.7) mm and (6.7 (1.9) mm, respectively; p < 0.001) states. During direct laryngoscopy, the occlusion rate of the oesophageal entrance was greater with cricoid compared with paralaryngeal force (46/74 vs. 26/74, respectively; p = 0.002). The relative position of the upper oesophageal entrance to the glottis may change after induction of anaesthesia and during direct laryngoscopy. Cricoid and paralaryngeal force both decrease the diameter of the upper oesophageal entrance in awake and anaesthetised states. Occlusion of the oesophageal entrance is achieved more frequently with cricoid force compared with paralaryngeal force during direct laryngoscopy. [ABSTRACT FROM AUTHOR]

Securing a clear airway is important for successful fibreoptic intubation. We investigated whether the jaw-thrust manoeuvre in the 25° semi-sitting position improves airway clearance compared with the supine position in 88 anaesthetised patients randomly assigned to the two positions. After induction of anaesthesia, the fibreoptic bronchoscope was advanced into the mouth along the dorsum of the tongue during the jaw-thrust manoeuvre. Airway clearance was assessed at the level of the soft palate and epiglottis. Patients in the 25° semi-sitting position had clearer airways (judged subjectively by a three-level scale) than those in the supine position at the soft palate level (p = 0.012). At the level of the epiglottis, airway clearance was equally good in both positions. The mean (SD) times to view the vocal cord and carina were shorter in the 25° semi-sitting position (4 (1) s and 8 (1) s, respectively) compared with the supine position (6 (3) s and 11 (3) s; p < 0.001, respectively). The time to achieve intubation was also shorter in the 25° semi-sitting position (21 (5) s) than in the supine position (25 (7) s; p = 0.018). [ABSTRACT FROM AUTHOR]

Electrochemical oxidation of humic acid has been conducted to evaluate the efficacy of the process for the destruction of high-molecular-weight (HMW) compounds. Experimental results show that the destruction of humic acid obtained by the electrolysis supported by chloride ion is much better than that obtained by sulfate ion. Accordingly, HMW compound such as humic substance is suggested to be resistant to directly anodic oxidation, but to be readily destroyed by an indirect oxidation of chlorine/hypochlorite during an electrochemical treatment process. The effects of operating parameters, including anode material, current density, electrolyte concentration, have been investigated in this study. A tertiary-oxide of Sn, Pd, Ru coated titanium (SPR) anode with high electrocatalytic activity was found to have high efficiency for humic acid destruction, and the destruction efficacy of humic substance increased with increasing current density and chloride concentration. In this study, gel permeation chromatography (GPC) and adsorptive organic halide (AOX) had been performed to examine the variation of organic characteristics during the electrochemical oxidation of humic acid. The results from GPC and AOX show that HMW organic compounds could be effectively destroyed by electrochemical oxidation process, and the process also produced less undesirable chlorinated byproducts than the chlorination process. From the above results, the electrochemical oxidation conducted by indirect oxidation effect of chlorine/hypochlorite could be concluded to be a feasible method for the destruction of HMW compounds. [ABSTRACT FROM AUTHOR]

The influence of SiO2 and Si3N4 dielectric matrices on the structural, phonon, luminescence and thermal properties of Ge quantum dots (QDs) has been experimentally investigated. Compared with the case of QDs in SiO2 layers, Si3N4 matrix imposes large interfacial surface energy on QDs and enhances their Ostwald ripening rate, appearing to be conducive for an improvement in crystallinity and a morphology change to a more perfectly spherical shape of Ge QDs. Quantum confinement induced electronic structure modulation for Ge QDs is observed to be strongly influenced not only by the QD size but also by the embedded matrix. Both matrix and surface effects offer additional mechanisms to QD itself for controlling the optical and thermal properties of the QDs. [ABSTRACT FROM AUTHOR]

In this study, the long-term stability of KEtX/Cu(OH)2 matrix under early-period and late-period landfill leachates was evaluated using semi-dynamic leaching test (SDLT), X-ray diffractometer (XRD) and fourier transform infrared (FTIR) techniques. The results of SDLT after 60-day periods of extraction indicated that the cumulative leaching of Cu was only 0.72% and 3.34% of the total Cu in the KEtX/Cu(OH)2 matrix under early-period and late-period landfill leachates, respectively. The investigation of crystallinity and functional groups between the leached KEtX/Cu(OH)2 matrices after 1-day and 60-day periods of extraction using XRD and FTIR indicated that the KEtX/Cu(OH)2 matrices were perfectly unaffectedby the extraction using early-period and late-period landfill leachates during the 60-day leach time. Consequently, the KEtX/Cu(OH)2 matrix had a stabilizing behavior extracted in landfill leachates. [ABSTRACT FROM AUTHOR]

Abstract: The Taiwan universities laboratory hazardous wastes have been treated by incineration at the temperature range of 1173–1273K. By X-ray absorption near edge structure (XANES) spectroscopy, mainly CuO and CuSO4 are found in the incineration bottom and fly ashes. The incineration fly ash can be stabilized thermally at 1773K in the plasma melting reaction chamber (integrated with the incinerator), and converted to slag. The concentration of leachable copper in the slag is reduced significantly mainly due to the fact that copper is encapsulated in the SiO2 matrix. In addition, the refined extended X-ray adsorption fine structure (EXAFS) spectra of copper also indicate formation of the Cu–O–Si species in the slag as the bond distances of 1.95Å for Cu–O and 2.67Å for O–Si are observed. This work exemplifies utilization of the synchrotron X-ray absorption spectroscopy to facilitate the thermal stabilization treatments of the fly ash hazardous waste using the plasma melting method. [Copyright &y& Elsevier]

During nasotracheal intubation, the tracheal tube passes through either the upper or lower pathway in the nasal cavity, and it has been reported to be safer that the tracheal tube passes though the lower pathway, just below the inferior turbinate. We evaluated the use of a nasogastric tube as a guide to facilitate tracheal tube passage through the lower pathway, compared with the 'conventional' technique (blind insertion of the tracheal tube into the nasal cavity). A total of 60 adult patients undergoing oral and maxillofacial surgery were included in the study. In 20 out of 30 patients (66.7%) with the nasogastric tube-guided technique, the tracheal tube passed through the lower pathway, compared with 8 out of 30 patients (26.7%) with the 'conventional' technique (p = 0.004). Use of the nasogastric tube-guided technique reduced the incidence and severity of epistaxis (p = 0.027), improved navigability (p = 0.034) and required fewer manipulations (p = 0.001) than the 'conventional' technique. [ABSTRACT FROM AUTHOR]

Interleukin (IL)-12 is a key factor that induces T helper cell type 1-mediated immunity and inflammatory diseases. In some colitis models, such as IL-10 knock-out (KO) mice, IL-12 triggers intestinal inflammation. An abundant amount of IL-12 is produced by intestinal macrophages in response to stimulation by commensal bacteria in IL-10 KO mice. Intact bacteria are more potent inducers of macrophage IL-12 production than cell surface components in this model. This suggested that cell surface receptor signalling and intracellular pathogen recognition mechanisms are important for the induction of IL-12. We addressed the importance of intracellular recognition mechanisms and demonstrated that signal transducers and activator of transcription 1 (STAT1) signalling activated bacterial phagocytosis and was involved in the induction of abnormal IL-12 production. In IL-10 KO mouse bone marrow-derived (BM) macrophages, Escherichia coli stimulation induced increased IL-12p70 production compared to lipopolysaccharide combined with interferon (IFN)-γ treatment. Significant repression of IL-12 production was achieved by inhibition of phagocytosis with cytochalasin D, and inhibition of de novo protein synthesis with cycloheximide. Induction of IFN regulatory factors-1 and -8, downstream molecules of STAT1 and the key transcription factors for IK-12 transcription, following E. coli stimulation, were mediated by phagocytosis. Interestingly, STAT1 was activated after stimulation with E. coli in IL-10 KO BM macrophages, although IFN-γ could not be detected. These data suggest that molecules other than IFN-γ are involved in hyper-production mechanisms of IL-12 induced by E. coli stimulation. In conclusion, enteric bacteria stimulate excessive IL-12p70 production in IL-10 KO BM macrophages via phagocytosis-dependent signalling. [ABSTRACT FROM AUTHOR]

Refractory pollutants, including lignin, tannic acid, chlortetracycline, and EDTA, were destroyed by an electrochemical oxidation method to evaluate the applicability of this method for industrial wastewater pretreatment. Operation parameters, such as supporting electrolyte,current density, and electrolyte concentration, have been investigated for their influences on COD removal efficiencies during electrolysis. In addition, gel permeation chromatography (GPC), Microtox test. and total organic halogen (TOX) analyses were performed to monitor the changes of organic characteristics of these refractory pollutants. Experimental results show that, among sulfate, nitrate, and chloride,chloride was the best supporting electrolyte, and during electrolysis, both COD and color removal efficiencies were improved by increasing current density and chloride concentration. From GPC analysis results, the electrochemical oxidation process readily destroys high-molecular-weight (HMW) organics. Microtox test results also show that the process can reduce the toxicity of these refractory organic compounds. In addition, TOX concentrations were found to increase at the beginning but then decline during the electrolysis. The above results suggest that the electrochemical oxidation process, which has good efficacy for detoxification and destruction of refractory pollutants, is a promising method for wastewater pretreatment. [ABSTRACT FROM AUTHOR]

Abstract: To better understand diffusion of copper in the micro- and mesopores, speciation of copper in a bi-porous molecular sieve (BPMS) possessing inter-connecting 3-D micropores (0.50–0.55nm) and 2-D mesopores (4.1nm) has been studied by X-ray absorption near edge structure (XANES) spectroscopy. It is found that about 77% (16% of CuO nanoparticles and 61% of CuO clusters) and 23% (CuOads) of copper can be diffused into the meso- and micropores, respectively, in the BPMS. At least two diffusion steps in the BPMS may be involved: (i) free diffusion of copper in the mesopores and (ii) diffusion-controlled copper migrating into the micropores of the BPMS. The XANES data also indicate that diffusion rate of copper in the BPMS (4.68×10−5 g/s) is greater than that in the ZSM-5 (1.11×10−6 g/s) or MCM-41 (1.17×10−5 g/s). [Copyright &y& Elsevier]