Search

To establish through analysis of the radial pressure pulse waveform the dose dependent effects of glyceryl trinitrate (GTN) on properties of different blood vessels.Radial pulse waveform was measured in randomised order before, during a five hour application of a GTN patch delivering 0.104-0.625 mg/h, and for two hours after patch removal. The radial pressure waveform (Millar applanation tonometer) was convolved into an ascending aortic wave using a generalised transfer function (SphygmoCor process) enabling measurement of aortic systolic, diastolic, pulse, mean, and augmented pressure and left ventricular ejection duration in addition to standard brachial cuff pressures.Fu Wai and Ren Ming hospitals in Beijing, China.46 recumbent hospitalised patients aged 56 (9) years, awaiting electrophysiological or other diagnostic studies, fasting, and with other treatments suspended.Conventional brachial pressure measures and data from the synthesised aortic pulse.There was no consistent change in heart rate or brachial pressures except for a decrease in systolic and pulse pressures (p0.01) at dose0.416 mg/h. In contrast, there were substantial and significant (p0.0001) decreases in aortic systolic, pulse, and augmented pressures at all doses, mean pressure (p0.001) at doses0.416 mg/h, and ejection duration (p0.001) at doses0.208 mg/h.Pulse waveform analysis exposes dose dependent effects of GTN on the aortic waveform, suggesting muscular conduit arterial dilatation with reduced wave reflection at the lowest dose, arteriolar dilatation and decreased peripheral resistance at the highest dose, and venous dilatation at the intermediate dose.

Due to the complexity of the numerical simulation of flow and/or water quality, there is an increasing demand for integration of recent knowledge management, artificial intelligence technology with the conventional hydraulic algorithmic models in order to assist novice application users in selection and manipulation of various mathematical tools. In this paper, a prototype knowledge management system on flow and water quality is addressed to simulate human expertise during the problem solving by incorporating artificial intelligence and coupling various descriptive knowledge, procedural knowledge and reasoning knowledge involved in the coastal hydraulic and transport processes. The system is developed through employing Visual Rule Studio, a hybrid expert system shell, as an ActiveX Designer under Microsoft Visual Basic 6.0 environment since it combines the advantages of both production rules and object-oriented programming technology. The architecture, the development and the implementation of the prototype system are delineated in details. Based on the succinct features and conditions of a variety of flow and water quality models, three kinds of class definitions, Section and Problem as well as Question are defined and the corresponding knowledge rule sets are also established. Both forward chaining and backward chaining are used collectively during the inference process. A typical example is also presented to demonstrate the application of the prototype knowledge management system.

Under the nondegenerate condition as in the diffusion case, see [14, 21, 6], the linear stochastic jump-diffusion process projected on the unit sphere is a strong Feller process and has a unique invariant measure which is also ergodic using the relation between the transition probabilities of jump-diffusions and the corresponding diffusions due to [22]. The unique deterministic Lyapunov exponent can be represented by the Furstenberg-Khas'minskii formula as an integral over the sphere or the projective space with respect to the ergodic invariant measure so that the almost sure asymptotic stability of linear stochastic systems with jumps depends on its sign. The critical case of zero Lyapunov exponent is discussed and a large deviations result for asymptotically stable systems is further investigated. Several examples are treated for illustration.

The challenge of achieving high resolution in binary reactions involving an outgoing high-energy neutron is solved by detecting the $ \gamma$ -ray decay of populated excited states in an array of escape-suppressed HPGe detectors in coincidence with fast neutrons. The selectivity of the arrangement is of the order of 1 in 1000 and is demonstrated by L = 0 two-proton stripping to 7/2- 2p-1h levels using the 59Co(3He, $n \gamma$ )61Cu reaction at E lab = 22.5 MeV. The observed relative two-proton stripping strengths are compared with large-basis shell-model calculations.

Numerical discretization schemes are developed to approximate functionals of stochastic differential equations with jumps, and the convergence is shown to have an appropriate order. For the Euler scheme and the second order weak scheme, the leading coefficient of their global errors are determined by the stochastic Taylor expansion. Based on the error expression, the extrapolation technique can be applied to get a higher order convergence. Numerical examples are provided to compare various weak schemes and extrapolations.

Based on the shuffle product expansion of exponential Lie series in terms of a Philip Hall basis for the stochastic differential equations of jump-diffusion type, we can establish Stratonovich–Taylor–Hall (STH) schemes. However, the STHr scheme converges only at order r in the mean-square sense. In order to have the almost sure Stratonovich–Taylor–Hall (ASTH) schemes, we have to include all the terms related to multiple Poissonian integrals as the moments of multiple Poissonian integrals always have lower orders of magnitudes as compared with those of multiple Brownian integrals.

We derive a product expansion of the exponential Lie series in terms of a Philip Hall basis for the Chen series corresponding to the stochastic jump diffusion as in Sussmann (in: C.I. Byrnes and A. Lindquist (Eds.), Theory and Applications of Nonlinear Control Systems, North-Holland, Amsterdam, 1986, pp. 323–335) for the deterministic case. Based on the expansion, we establish the Stratonovich–Taylor–Hall (STH) schemes such that each scheme involves only the minimum number of multiple stochastic integrals, which can be regarded as systems of stochastic differential equations and approximated by a lower order scheme with an appropriate step size to ensure the necessary accuracy. Mean-square convergence of the STH schemes is shown and numerical examples are provided to illustrate the results.

Artificial instantaneous discharge of buoyant fluid in ambient waters is usually carried out at the time of maximum cross-flow so that the resulting dilution is optimal. The determination of the characteristics of this problem is important for environmental impact study but has seldom been studied. To investigate the transport, mixing, and dilution of an isolated cloud of buoyant fluid in cross-flow ambient, a three-dimensional buoyancy extended k-e model is employed. The computed results show that two flow regimes exist. First is the initial dumping regime in which the effect of crosscurrent and the associated turbulence on the longitudinal width and the average dilution is insignificant as compared to the effect of buoyancy on those quantities. The flow and mixing characteristics in this regime are close to those in the case of stagnant ambient. Second is the ultimate regime in which the effect of buoyancy on the longitudinal width and the average dilution is small as compared to the effect of cross-flo...

As multiple stochastic integrals are not very easy to simulate, we would like to treat them as solutions of systems of stochastic differential equations and solve them successively and recursively approximated by the stochastic Taylor expansion as a Chen series in terms of a Philip Hall basis or Lyndon basis. We can save sufficient values of multiple stochastic integrals with independent sample paths in a look-up table for future use. The table can be used to implement high order schemes to solve stochastic differential equations numerically. A numerical example will be shown to illustrate the efficiency.

In this paper, we extend the result of Gaines [4] to show that Lyndon set forms an algebraicbasis for the set of multiple stochastic integrals with respect to Brownian motions and Poissonprocesses, so that any multiple stochastic integral can be expressed as a polynomial of Lyndonbasis. The results for Philip Hall basis is similar. From the computational point of view, theadoption of either of the bases has the same effect on reducing much computing work of thenumerical approximation for stochastic differential equations of jump-diffusion type

Following the approach of Sussmann [16] to expand the Chen series as a product of an exponential Lie series based on a Philip Hall basis, this paper constructs the Stratonovich-Taylor-Hall (STH) discretization schemes of both integral and fractional orders for stochastic differential equations. The STH schemes are numerically efficient in the sense that they involve only the minimum numbers of multiple stochastic integrals. General multiple stochastic integrals are regarded as systems of stochastic differential equations that can be solved by lower order schemes. Convergence of the STH schemes is proved in the almost sure sense by means of the discrete stochastic Gronwall inequality

Proton decoupling and nuclear Overhauser effect (NOE) enhancement significantly improve the signal-to-noise ratio and enhance resolution of metabolites in in vivo 31P MRS. We obtained proton-decoupled, NOE-enhanced, phospholipid-saturated 31P spectra localized to defined regions within the normal liver using three-dimensional chemical shift imaging. Proton-decoupling resulted in the resolution of two major peaks in the phosphomonoester (PME) region, three peaks in the phosphodiester (PDE) region and a diphosphodiester peak. In order to obtain molar quantitation, we measured the NOE of all hepatic phosphorus resonances, and we corrected for saturation effects by measuring hepatic metabolite T1 using the variable nutation angle method with phase-cycled, B1-independent rotation, adiabatic pulses. After corrections for saturation effects, NOE enhancement, B1 variations and point spread effects, the following mean concentrations (mmol/l of liver) (+/-SD) were obtained: [PME1] = 1.2 +/- 0.4, [PME2 + 2,3-DPG] = 1.1 +/- 0.1, [Pi + 2,3-DPG] = 2.8 +/- 0.5, [GPEth] = 2.8 +/- 0.7, [GPChol] = 3.5 +/- 0.6 and [beta-NTP] = 3.8 +/- 0.3. T1 and NOE enhancement were strongly correlated (r = 90), and indicated that the fractional contribution of 1H-31P dipolar relaxation to total 31P relaxation is minimal for NTPs, moderate for PMEs and high for PDEs in liver. Proton-decoupling and NOE enhancement permit one to obtain more information about in vivo metabolism of liver than previously available and should enhance the utility of 31P MRS for the study of hepatic disorders.

Simultaneous multivoxel 31 P and 19 F 3D localized NMR spectroscopy is demonstrated on a phantom and in the liver of patients undergoing bolus-infusion 5-fluorouracil chemotherapy. The 19 F and 31 P spectra were localized with 8 x 8 x 8 3D chemical-shift imaging, with both nuclei sharing the same field of view and voxel size (27 and 64 ml in phantom and liver, respectively) using a 1.5-Tesla clinical imager with two RF channels and a dual-tuned surface coil. The repetition time (TR = 0.26 s) and Ernst nutation angles (θ E = 32° for 19 F, 28° for 31 P) were chosen to optimize the signal-to-noise ratio (SNR) per-unit time for the 0.5- to 2-s T 1 range of the 19 F and 31 P metabolites of interest. The overall examination time, including tuning, imaging, shimming and dual-nuclear spectroscopy, was under 90 min. Simultaneous acquisition of 31 P and 19 F spectra will permit the study of the influence of hepatic and/or tumor metabolism on the uptake and catabolism of fluoropyrimidine drugs with no extra measurement time. 5-fluorouracil.

Tong's threshold models have been found useful in modelling nonlinearities in the conditional mean of a time series. The threshold model is extended to the so-called double-threshold ARCH(DTARCH) model, which can handle the situation where both the conditional mean and the conditional variance specifications are piecewise linear given previous information. Potential applications of such models include financial data with different (asymmetric) behaviour in a rising versus a falling market and business cycle modelling. Model identification, estimation and diagnostic checking techniques are developed. Maximum likelihood estimation can be achieved via an easy-to-use iteratively weighted least squares algorithm. Portmanteau-type statistics are also derived for checking model adequacy. An illustrative example demonstrates that asymmetric behaviour in the mean and the variance could be present in financial series and that the DTARCH model is capable of capturing these phenomena.

This paper examines the potential and limitations of peak area quantitation of biological NMR spectra using principal component analysis (PCA), including its requirement for prior knowledge. The principles of the method are presented without in-depth mathematical treatment. PCA is illustrated for simulated data, 31 P NMR spectra obtained consecutively over 1-2.5 days from perfused Rat-2 cells metabolizing the choline analogue phosphoniumcholine (Cho p ) and in vivo proton-decoupled, NOE-enhanced, three-dimensional CSI localized 31 P NMR spectra of the liver of healthy volunteers. The results show that PCA can be used to quantitate strongly overlapping peaks without prior knowledge of the peak shapes or positions and to reconstruct spectra with significantly reduced noise variance. Two major limitations of PCA are presented : (1) PCA cannot separate peaks whose intensities are well correlated ; (2) PCA is sensitive to differences in chemical shift and line-width of peaks between spectra. The discussion focusses on what knowledge of the biological and spectroscopic features of the samples and the principles of PCA is necessary for peak area quantitation via PCA.

The radula of the limpet, Cellana toreuma, consists of a continuous series of teeth in various stages of iron biomineralization. The major iron-binding protein of the limpet's iron-containing granule (siderosome) has been purified and identified as ferritin. Limpet ferritin has a M(r) of 575 kDa and can be resolved into two bands by SDS-PAGE analysis, with respective M(r)s of 26 and 21 kDa. The partial N-terminal amino acid sequences of these two subunits were confirmed, and antisera against them were respectively generated. The specifity of these two antisera shows no difference between them. By using transmission electron microscopy and immunogold staining techniques the following two events were revealed: (1) in the superior epithelial cell of the radula, ferritin was disassembled through autophagy or heterophagy before exocytosis; (2) of the limpet ferritin, at least the 26-kDa subunit was found to pass through the microvilli, resulting in the accumulation of iron in the extracellular tooth chamber and the formation of goethite needles. Intracellular ferritin being translocated to the extracellular environment is discussed in the text.

Cell, scaffold, and growth information are considered as the basic elements of tissue engineering. Scaffolds are expected to support cell colonization, migration, growth, and differentiation and to guide the development of the required tissue. This chapter discusses the state-of-the-art in scaffold design and fabrication issues based on microelectromechanical system (MEMS)-manufacturing techniques. It begins with a discussion of the tissue scaffold design considerations including surface characteristics and mechanical properties. The subsequent section then goes into details the main point of this chapter – tissue scaffold fabrication using MEMS approaches. Available applications of the MEMS-fabricated tissue scaffolds including cardiovascular, nervous, bone, and stem cell differentiation are illustrated in the succeeding section. A brief conclusion that covers the future work is given in the last section.

Streptococcus agalactiae (Group B streptococcus) has emerged as an important pathogen that affects humans and animals, including aquatic species. S. agalactiae infections are becoming an increasing problem in aquaculture and have been reported worldwide in a variety of fish species, especially those living in warm water. Recently, a very serious infectious disease of unknown aetiology broke out in ya-fish (Schizothorax prenanti) farms in Sichuan Province. A Gram-positive, chain-forming coccus was isolated from moribund cultured ya-fish. The goals of this study were to identify the bacterial strains isolated from diseased fish between 2009 and 2011 in Sichuan Province, China, to evaluate the pathogenicity of the pathogen in ya-fish, crucian carp (Carassius carassius) and the Nile tilapia (Oreochromis niloticus); and to determine the susceptibility of the pathogen strains to many currently available anti-microbial agents. The virulence tests were conducted by intraperitoneal injection of bacterial suspensions. In this study, four strains of a Gram-positive, chain-forming coccus were isolated from moribund cultured ya-fish (S. prenanti). The coccoid microorganism was identified as S. agalactiae using a commercial streptococcal grouping kit and 16S rDNA sequencing analysis. Susceptibility of the isolates to 22 antibiotics was tested using the disc diffusion method. All isolates showed a similar antibiotic susceptibility, which were sensitive to amoxicillin, ciprofloxacin, lomefloxacin, chloramphenicol, rifampin, vancomycin, azithromycin, florfenicol, cefalexin, cefradine and deoxycycline and resistant to gentamicin, sinomin (SMZ/TMP), penicillin, tenemycin, fradiomycin and streptomycin. Furthermore, the virulence tests were conducted by intraperitoneal injection of the isolated strain GY101 in ya-fish, crucian carp and the Nile tilapia. This coccus was lethal to ya-fish, Nile tilapia and crucian carp. The mortality rates of infected ya-fish were 100%, 100%, 60% and 20% at doses of 1.0 × 10⁷, 1.0 × 10⁶, 1.0 × 10⁵ and 1.0 × 10⁴ CFU/fish, respectively. The values were 100%, 80%, 60% and 30% for Nile tilapia and 100%, 60%, 10% and 0% for crucian carp. To our knowledge, this is the first report of S. agalactiae as a pathogen of ya-fish.

An experimental system for single-phase gas flow in microtubes has been developed. Theeffects of viscous heating and compressibility on the flow and temperature field were stud-ied for a wide range of governing parameters. Also, an analytical=numerical model ofthe flow was developed. Numerical results for the flow and heat transfer in the slip flowregion were found to agree quite well with the experimental data, lending support to themodel. The study provides greater physical insight into and understanding the effects ofviscous dissipation and compressibility in microtube flow and the associated heat trans-fer. In addition, the combined experimental and numerical simulation approaches of theprocess can be used for control and optimization of systems based on microtube heattransfer. [DOI: 10.1115/1.4004391]Keywords: microtube, compressibility, viscous heating, temperature field

A Reynolds‐averaged Navier‐stokes equations (RANS) model using the body force method (BFM) has been developed to simulate open‐channel flows over gravel beds. The momentum equation is modified by introducing the form drag as an extra body force term to represent the gravel‐bed resistance. By applying the body force within the roughness layer of the flow over small‐scale roughness, it is found that the body force coefficient frk varies inversely with the roughness length scale ks. The method is robust, not sensitive to mesh resolution and is easily extended to deal with large scale roughness.

The honeybee is one of the few organisms that can deposit iron minerals intracellularly. Numerous iron granules are formed in the trophocytes, which are located in the abdomen, beginning on the second day after eclosion. The sequential events of iron deposition in honeybees have been determined and the special features of this biomineralization system are (1) that iron deposition vesicles (IDVs) enlarge by fusing with one another; (2) that dense particles (approx. 7.5nm in diameter) are the basic building blocks in the formation of iron granules; and (3) that a cloudy layer just beneath the membrane of IDVs may play an important role in the formation of the dense particles. The iron granules seem to be randomly distributed in the trophocytes of the worker and drone. In the queen, however, they are clustered and peripherally located. This distinct difference in the iron granule distribution between members of the hive suggests that these iron granules may have some biological functions. A detailed analysis of total iron content during the life cycle of honeybees has shown that iron granules in the adult worker contain approximately 1% of the total iron content and also account for approximately 3% of the increase in iron content that occurs between the newly eclosed worker stage and the adult worker stage.

The current study aims to identify the type of cell-matrix adhesions of hMSCs in 3D collagen constructs and to investigate the effects of dynamic compression on the type, morphology and composition of cell-matrix adhesions, particularly to observe whether the compression stimulates the maturation or evolvement of 3D matrix adhesion in hMSC-collagen constructs. Preliminary results demonstrated the colocalization of integrin α 5 β 1 and fibronectin in cell-matrix adhesions in loaded constructs, partially fulfilling the requirements for 3D matrix adhesion to evolve. In addition, fibronectin was shown to be organized into tiny-dotted adhesions in loaded constructs in a loading duration dependent way, suggesting dynamic compression may be able to mature adhesions in the constructs, hopefully into 3D matrix adhesions. It was also demonstrated that hMSCs plated onto their own cell-derived matrices form elongated adhesions which are similar to 3D matrix adhesions formed by fibroblasts. Further characterization on the cell-matrix adhesions of hMSCs in 3D collagen constructs and identification of differences in adhesions between loaded and unloaded constructs are underway.

This paper is concerned with the ℋ ∞ dynamic output feedback (DOF) control problem for continuous-time switched stochastic systems. By applying the average dwell time method and the piecewise Lyapunov function technique, a sufficient condition is first proposed, which guarantees the closed-loop switched stochastic system to be mean-square exponentially stable with a weighted ℋ ∞ performance. The ℋ ∞ DOF controller can be found by solving a set of linear matrix inequalities (LMIs). A numerical example is provided to illustrate the effectiveness of the proposed theories.

This study discussed the optical pumping effects by two trapped electrons competition in optical stimulated luminescence processes. In simulation, quantum probability concept was recruited as the criterion of pumping electron mechanism and the optical luminescence properties could be obtained by solving the dynamics equations. The result not only indicated the optically stimulated luminescence which was dominantly affected by initial trapped concentration, trapped energy levels, the profile of pumping photon energy but predicted the optically stimulated luminescence material's behavior in clean-down electrons process.

An experimental system for single-phase gas flow in microchannels was set up. The effects of viscous heating on the temperature field in the flow were studied experimentally. Also, a theoretical model for the flow and heat transfer in the slip flow region was developed and the resulting equations were solved analytically by using a method based on the superposition principle. The results obtained agree well with the experimental data. The study also provides greater insight into microchannel flow and the associated heat transfer.Copyright © 2009 by ASME

Flooding in a street network may occur under an extremely heavy rainfall. The determination of flow distribution in street networks thus is important for the design of flood protection measures. The junction of streets is generally a cross and the flow there is highly three-dimensional. If the slopes of the streets are steep, the inflows will be supercritical and hydraulic jumps will occur close to the junction. To reduce the degree of empiricism, a 3D RANS (Reynolds Averaged Navier-Stokes equation) model has been implemented in this study to investigate the steep flow phenomena in a channel crossing. The numerical model utilizes the split-operator approach, in which the advection, diffusion and pressure propagation are solved separately. The free surface elevation is determined by solving the vertically integrated mass conservation equation. The numerical model has been validated for the case of a hydraulic jump in an open channel. The model is then applied to simulate the flow in a channel crossing. The results reproduce the hydraulic jump and hydraulic drop phenomena and predict accurately the relationship between the input power ratio and the outflow discharge ratio of the channel crossing.

Aimed at the problems, such as the poor synchronization performance of heavy crane being operated coordinately and huge amounts of on-line calculation using the existed relative coupling strategy, a position synchronization controller based on adjacent relative coupling strategy and backstepping is designed. The simulation model is constructed in Matlab/Simulink environment, and the Simulink results show the position synchronization control system has a better position synchronization behavior and a quick convergence rate.

This prospective self-controlled study was designed to evaluate the influences of head flexion on airway seal, quality of ventilation, and orogastric tube placement through the ProSeal laryngeal mask airway (ProSeal LMA) in 80 anaesthetised, paralysed adult patients. After the ProSeal LMA was inserted and the cuff pressure was set at 5.9 kPa, ventilation quality, airway seal pressure, fibreoptic positions of the cuff and the drainage tube, orogastric tube placement and efficacy of intermittent positive pressure ventilation (IPPV) were assessed in two randomly selected positions: neutral and flexed position. When compared to the neutral head position, the head flexed significantly improved the airway seal pressure and the quality of ventilation of the ProSeal LMA (p0.05). Fibreoptic scores of the cuff position did not correlate with either the ability to obtain excellent or adequate ventilation through the ProSeal LMA or the ability to generate an airway seal pressure ofor= 2 kPa. Orogastric tube placement via the drainage tube was successful on the first attempt in all patients in the neutral position compared with seven failures following three attempts in the flexed position (p0.05). There were no significant differences between the two head positions in the volume of air required to obtain an intracuff pressure of 5.9 kPa, fibreoptic score of the drainage tube position, and expiratory tidal volume and peak inspiratory pressure during IPPV (p0.05). In conclusion, head flexion improves airway seal and ventilation quality of the ProSeal LMA. However, placement of an orogastric tube via the drainage tube is impaired in the flexed position compared to the neutral position. Fibreoptic scoring of the ProSeal cuff position is not an accurate test to assess the airway seal and ventilation function.

Tensile creep studies were carried out to evaluate the creep performance of AS800 silicon nitride samples extracted from the surface and bulk regions of as-processed billets at 1350 C in air. The objective of this study was to understand the creep properties of the silicon nitride in the as-processed surface region and determine if they are comparable to those obtained from the bulk region. The results indicated that samples from the as-processed surface region exhibited higher creep rates and shorter lifetimes as compared with those obtained from the bulk region. The poor creep performance of material from the as-processed surface region was due to the higher content of glassy phase enriched with oxygen and sintering additive elements.

The evaluation was done between 1300 and 1425 C in ambient air. Minimum creep rate was evaluated vs tensile stress and temperature, and measured tensile creep performances of two different specimen geometries (buttonhead and dogbone - machined from same billet) were compared. This Si nitride exhibited comparable or better creep resistance than other Si nitrides described in the literature. Measured creep response of the material and lifetime were observed to be geometry dependent; the smaller cross-sectioned dogbone samples exhibited faster creep rates and shorter lives, presumably due to faster oxidation-induced damage in this geometry. The tensile creep rates and lifetimes were found to be well represented by the Monkman- Grant relation between 1350 and 1425 C, with some evidence suggesting stratification of the data for the 1300 C tests and a change in dominant failure mode between 1300 and 1350 C. Lastly, values of the temperature-compensated stress exponent and activation energy for tensile creep were found to decrease by 80 and 75% in compression, respectively, illustrating anisotropic creep behavior in this Si nitride.

Summary Background Parental atopy and environmental exposure are recognized risk factors for atopic eczema (AE) in childhood. However, the relative contributions of specific risk factors and the overall contributions of hereditary and environmental exposure remain unexplored. Objectives To identify risk factors, estimate the population attributable risk (PAR) of environmental exposure, and compare the AE data for boys vs. girls in primary-school children. Methods During a February to June 2001 cross-sectional, Taiwan-based questionnaire survey, we investigated 23 980 children from 22 primary schools, all located within 1 km of an air-monitoring station. Results The 12-month prevalence of AE was reported as 6·1% in boys and 4·9% in girls. In both sexes, the risk of AE was strongly associated with parental atopy and perceived ambient air pollution. The presence of cockroaches [odds ratio (OR) 1·18, 95% confidence interval (CI) 1·00–1·40] and visible mould on walls at home (OR 1·46, 95% CI 1·22–1·70) were also significantly related to AE for girls; however, only visible mould on walls (and not the presence of cockroaches) at home was related to AE for boys (OR 1·40, 95% CI 1·18–1·66). While mutually adjusted models were applied, we found adjusted ORs and PARs were similar in boys and girls in hereditary and outdoor environmental factors. The PAR of indoor environmental factors was higher in girls (8·4%) than in boys (5·5%). There was no interaction between parental atopy and environmental factors. Conclusions Parental atopy contributed more to AE than indoor or outdoor environmental factors. Girls may be more susceptible to indoor environmental factors than boys.

The available data provide inconsistent results on the efficacy of small-dose remifentanil attenuating the cardiovascular response to intubation in children. Therefore, this randomized double-blind study was designed to assess the ability of different small doses of remifentanil on the cardiovascular intubation response in children, with the aim of determining the optimal dose of remifentanil for this purpose.One hundred and twenty-four children aged 3-9 yr were randomized to one of four groups to receive the following in a double-blind manner: normal saline (Group 1), remifentanil 0.75 microg kg(-1) (Group 2), remifentanil 1 microg kg(-1) (Group 3) and remifentanil 1.25 microg kg(-1) (Group 4). Non-invasive blood pressure and heart rate were recorded before anaesthesia induction (baseline value), immediately before intubation (postinduction values), at intubation and at 1 min intervals for 5 min after intubation.Tracheal intubation caused significant increases in systolic blood pressure and heart rate in Groups 1-3 compared with the baseline values. The maximum percent increases of systolic blood pressure and heart rate were 10% and 26% of the baseline values, respectively, in Group 2; 5% and 14% in Group 3; and 1% and 8% in Group 4 compared with 27% and 37% in Group 1. Except for the Group 3 vs. Group 4 comparison, there were significant differences among the four groups in the maximum percent increases of systolic blood pressure and heart rate.When used as part of anaesthesia induction with propofol and vecuronium in children, bolus administration of remifentanil resulted in a dose-related attenuation of the cardiovascular intubation response.

The aims of this study were to further evaluate the efficacy and safety of the GlideScope as a device to aid orotracheal intubation, and to further determine whether the GlideScope can provide a better laryngeal view in patients predicted to have a difficult laryngoscopy compared to the Macintosh laryngoscope.Ninety-one adult patients, ASA physical status I-II, scheduled for elective plastic and intraoral surgery under general anesthesia requiring orotracheal intubation were included in this study. The laryngeal view was estimated by the classification of Cormack-Lehane and the orotracheal intubation was then performed using a GlideScope. The times required for full visualization of the glottis and for the successful tracheal intubation were recorded, respectively. Noninvasive blood pressure and heart rate were also recorded before (baseline values) and immediately after induction (postinduction values), at intubation and every minute for 5 min after intubation. In patients preoperatively predicted to have a difficult laryngoscopy, the laryngeal views obtained by a GlideScope and a Macintosh laryngoscope were also compared.All patients were successfully intubated using a GlideScope, of which 97% (88/91) required only one attempt. In the patients with successful intubation at one attempt, the times required for full visualization of the glottis and for successful tracheal intubation were 21+/-9 s and 38+/-11 s, respectively. The orotracheal intubation caused significant increases in blood pressure and heart rate compared to the postinduction values, and the maximal values of blood pressure and heart rate during the observation were significantly higher than the baseline values. In 27 patients preoperatively predicted to have a difficult laryngoscopy, the laryngeal views in using the GlideScope were significantly better than those in using the Macintosh laryngoscope. The incidence of minor upper airway trauma was 3.4% in all patients.The orotracheal intubation using a GlideScope had advantages of easy and simple operation, excellent laryngeal view, and the ability to provide an improved laryngeal view in the patients with a difficult laryngoscopy. The general anesthesia of clinical standard depth was able to suppress the pressor response, but not temporary tachycardiac response to the orotracheal intubation using a GlideScope.

BACKGROUND: We designed this prospective self-controlled study to assess whether cricoid pressure hampers placement of and ventilation through the ProSeal laryngeal mask airway (ProSeal LMA) in anesthetized, paralyzed adult patients. METHODS: After induction of anesthesia, the ProSeal LMA was inserted using the introducer tool with cricoid pressure advanced as far as possible, and the cuff pressure was set at 60 cm H 2 O. Ventilation adequacy and anatomic position were scored using measures previously described for ProSeal LMA assessment. Airway seal pressure was recorded. Cricoid pressure was then released, the ProSeal LMA further advanced and reseated, and the assessment repeated. RESULTS: Lung ventilation scores, anatomic position scores, and airway seal pressure were significantly better after release of cricoid pressure and reseating of the ProSeal LMA than in the first position, where the ProSeal LMA was seated with cricoid pressure (P < 0.05). Expiratory tidal volume during intermittent positive pressure ventilation was similar with and without cricoid pressure, but peak inspiratory pressure decreased from 28 cm H 2 O with cricoid pressure to 14 cm H 2 O without cricoid pressure (P < 0.05). CONCLUSIONS: Cricoid pressure applied before insertion hampered proper placement of the ProSeal LMA. Temporary cricoid pressure release during insertion allowed the device to be advanced to the proper position. After correct placement of the ProSeal LMA, application of cricoid pressure did not change tidal volume, but produced a significant increase in peak inspiratory pressure.

Previously, we and others have demonstrated the association of a C/T single nucleotide polymorphism (SNP), in the Kozak sequence of CD40, with Graves' disease (GD). Here, using an expanded data set of patients, we confirm the association of the CD40 SNP with GD (n=210, P=0.002, odds ratio (OR)=1.8). Subset analysis of patients with persistently elevated thyroid peroxidase (TPO) and/or thyroglobulin (Tg) antibodies (Abs), (TPO/Tg Abs), after treatment (n=126), revealed a significantly stronger association of the SNP with disease (P=5.2 x 10(-5), OR=2.5) than in GD patients who were thyroid antibody-negative. However, the CD40 SNP was not associated with TPO/Tg Abs in healthy individuals. Next, we tested the CD40 SNP for association with Myasthenia Gravis (MG), which, like GD is an antibody-mediated autoimmune condition. Analysis of 81 MG patients found no association of the SNP with disease. Functional studies revealed significant expression of CD40 mRNA and protein in the thyroid (target tissue in GD) but not in skeletal muscle (target tissue in MG). Combined, our genetic and tissue expression data suggest that the CD40 Kozak SNP is specific for thyroid antibody production involved in the etiology of GD. Increased thyroidal expression of CD40 driven by the SNP may contribute to this disease specificity.

Background Previous studies have demonstrated a significant difference in the circulatory responses in adults to fiberoptic nasotracheal intubation (FNI) and fiberoptic orotracheal intubation (FOI). But, it is unknown whether there is a clinically relevant difference in the circulatory responses in children to these two intubation methods. Methods In this randomized clinical study, we compared the arterial blood pressure and heart rate changes during FNI and FOI in 66 children, ASA physical status I-II, aged 3-9 yr scheduled for elective plastic surgery. After anesthesia induction with fentanyl-propofol and vecuronium, fiberoptic intubation was performed. Noninvasive arterial blood pressure and heart rate were recorded before (baseline values) and after anesthesia induction (postinduction values), at intubation, and every minute for the first 5 min after intubation. The maximum values of arterial blood pressure and heart rate during the observation were also recorded. Results The total intubation time was significantly longer in the FNI group than in the FOI group. Both FOI and FNI caused significant increases in arterial blood pressure and heart rate compared with the baseline and postinduction values. Arterial blood pressure and heart rate at intubation and after intubation, and their maximum values during the observed periods were significantly lower in the FNI group compared with the FOI group. The times required to reach the maximum values of systolic blood pressure and heart rate were significantly longer in the FNI group than in the FOI group, but the times required for recovery of systolic blood pressure and heart rate to postinduction values were significantly shorter in the FNI group than in the FOI group. After the intubation, the times required to reach the peak levels of systolic blood pressure and heart rate were not significantly different between the two groups. Conclusions Both FOI and FNI can cause significant circulatory responses in healthy anesthetized children, and the circulatory responses to FNI are fewer and of a shorter duration than those to FOI.

The circulatory responses to fibreoptic intubation under general anaesthesia were studied in 60 adult female patients who were randomly assigned to receive either the oral or nasal route for insertion. Non-invasive blood pressure and heart rate were recorded before anaesthesia induction (baseline values), immediately after anaesthesia induction (post-induction values), at intubation and every minute for a further 5 min. The product of heart rate and systolic blood pressure (rate pressure product) at every time point was also calculated. The results showed that both fibreoptic orotracheal intubation and fibreoptic nasotracheal intubation resulted in significant increases in blood pressure, heart rate and rate pressure product compared to baseline and post-induction values. The times required to reach the maximum values of systolic blood pressure and heart rate were significantly longer in the fibreoptic nasotracheal intubation group than in the fibreoptic orotracheal intubation group. There were no significant differences between the two groups in blood pressure, heart rate and rate pressure product at any measuring point, or in the maximum values during observation. The time required for recovery of systolic blood pressure to the post-induction value was not significantly different between the two groups, but the time required for recovery of heart rate to post-induction value was significantly longer in the fibreoptic orotracheal intubation group than in the fibreoptic nasotracheal intubation group. It was concluded that both fibreoptic orotracheal and fibreoptic nasotracheal intubations could cause a similar magnitude of circulatory responses in general anaesthetised, female adults, but the tachycardic response to fibreoptic orotracheal intubation lasted longer than that to fibreoptic nasotracheal intubation.

Blood pressure and heart rate changes during nasotracheal intubation under general anaesthesia were studied in 100 patients who were randomly allocated to fibreoptic bronchoscope or direct laryngoscopy intubation. Noninvasive blood pressure and heart rate were recorded before and immediately after anaesthesia induction, at anaesthesia intubation and every minute thereafter for 5 min. Nasotracheal intubation was accompanied by significant increases in blood pressure and heart rate compared to baseline values in both groups. Blood pressure and heart rate at intubation, and the maximum values of blood pressure during the observation were significantly higher in the fibreoptic bronchoscope group. However, the maximum values of heart rate were not significantly different between the two groups. Fibreoptic nasotracheal intubation may result in more severe pressor and tachycardiac responses than direct laryngoscopic nasotracheal intubation.

Summary Background and objectives: Autonomic circulatory regulation and airway anatomy in children are significantly different from those in adults. There is no available published data to compare whether there is a clinically relevant difference in the haemodynamic responses to fibreoptic orotracheal intubation (FOI) under the same conditions between children and adults. In this randomized clinical study, we compared the blood pressure (BP) and heart rate (HR) changes during FOI in 40 children aged 3.5–9 yr and 40 adults aged 21–57 yr, ASA 1 scheduled for elective plastic surgery under general anaesthesia requiring orotracheal intubation. Methods: Anaesthesia was induced with intravenous (i.v.) injection of fentanyl and propofol, and face mask inhalation of isoflurane before FOI. Noninvasive BP and HR were recorded before induction (baseline values), after induction (postinduction values), at intubation and for 5 min after intubation at 1-min intervals. The percentage changes of BP and HR at each time point were calculated. Results: In children and adults, HR at intubation and 1–3 min after intubation were significantly higher than baseline and postinduction values. In adults, BP at intubation increased significantly compared to the postinduction values but did not exceed baseline values. In children, BP at intubation and 1 min after intubation were significantly higher than postinduction and baseline values. As compared to adults, FOI caused a more significant pressor response in children. The percentage changes of BP at intubation and 1 min after intubation were larger in children than in adults. However, there was no significant difference in the percentage change of HR during the observation between children and adults. Conclusions: Under general anaesthesia, FOI might cause a more significant pressor response in children than in adults.

Summary Background: The aims of this study were to evaluate the incidence of difficult laryngoscopy in infants with cleft lip and palate and to observe its relationships with age, sites, and degrees of deformities. Methods: A total of 985 infants aged 1 month to 3 years, undergoing repair of cleft lip and palate were included in this study. The infants suffering from unilateral cleft lip, simple cleft palate, and combined bilateral cleft lip and palate were 465, 421, and 79 respectively. They were divided into three groups according to age; 1–6 months group, 6–12 months group and 1–3 years group. Results: The total incidence of difficult laryngoscopy was 4.77%. The incidence of difficult laryngoscopy was closely related to age, sites and degrees of deformities, and micrognathia. The incidence of difficult laryngoscopy was 7.06% in 1–6 months group, 2.90% in 6–12 months group, and 3.13% in 1–3 years group, and was greatest for infants with combined bilateral cleft lip and palate, less for those with left cleft lip and least for those with right cleft lip and simple cleft palate. The incidences of difficult laryngoscopy in infants with and without micrognathia were 50% and 3.83% respectively. The incidences of moderately difficult, difficult, and failed intubations were 1.02%, 0.91%, and 0.102% respectively. Conclusions: Infants with cleft lip and palate, left cleft lip and alveolus, combined bilateral cleft lip and palate, micrognathia, and age