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Objective To investigate the effect of air pollution on gout development. Methods A total of 170318 participants were enrolled. These pollutants were considered: carbon monoxide (CO), fine particulate matter 2.5 (PM2.5), total hydrocarbons (THC) and methane (CH4). The yearly average concentrations were calculated from 2000 to 2011. Univariate and multivariate analyses by Cox proportional hazard regression models were adopted to estimate hazard ratios for gout in the Q2–Q4 concentrations of air pollutants compared with the Q1 concentration. Results In THC, relative to the Q1 concentration, the risk of gout was higher in participants exposed to the Q2–Q4 concentrations [adjusted hazard ratio (aHR), 1.10 with 95% confidence interval (CI), 1.01–1.19 in the Q2 concentration of THC; aHR, 4.20 with 95% CI, 3.93–4.49 in the Q3 concentration of THC; aHR, 5.65 with 95% CI, 5.29–6.04 in the Q4 concentration of THC]. In regard to CH4, when the Q1 concentration was defined as the reference, the risks of gout were increased for participants exposed to the Q2, Q3 and Q4 concentrations (aHR, 1.16 with 95% CI, 1.06–1.26 in the Q2 concentration of CH4; aHR, 2.37 with 95% CI, 2.20–2.55 in the Q3 concentration of CH4; aHR, 8.73 with 95% CI, 8.16–9.34 in the Q4 concentration of CH4). Conclusions Association between air pollution and risk of gout was noted. [ABSTRACT FROM AUTHOR]

The saturation magnetostriction of sputtered Co/Cu/Co thin films affected by preferred crystal orientation distribution of NiFe underlayers has been investigated. The experimental results indicated that preferred crystal orientation of NiFe underlayers plays a significant role in affecting the magnetoelastic behavior of coupled Co films separated by a thin Cu film. Negative value of saturation magnetostriction (-4.9x[10.sup.-6]) was obtained on sample film deposited on the NiFe underlayer with a more random crystal orientation distribution, while positive value of saturation magnetostriction (+11.6x[10.sup.-6]) was found on sample film deposited on highly [111] oriented NiFe film. It is clear that the preferred crystal orientation distribution of NiFe underlayers has a marked effect on the saturation magnetostriction of Co/Cu/Co films that [[Lambda].sub.s] is very sensitive to film structure and crystalline orientation texture.

The magnetic and electronic properties of composites consisting of oxidized multiwall carbon nantubes (MWNTs) dispersed in elastomeric poly(ether-ester) segmented block copolymer have been studied by means of electron spin resonance (ESR) and dc magnetization measurements. A marked reduction in the MWNT diamagnetic response is identified, indicative of substantial hole doping related to the oxygen functional groups on the oxidized carbon nanotube's surface. Both ESR and the static magnetization reveal considerable enhancement of the spin susceptibility due to an excessive increase in the density of paramagnetic defects, which are sensitive to the dynamical polymer relaxation and thus to the MWNT-polymer interfacial coupling. [ABSTRACT FROM AUTHOR]

The magnetic properties of two biogenic polyamine copper complexes were investigated by dc magnetization and electron paramagnetic resonance (EPR) measurements. The variation in temperature of the low field magnetization reveals that the absence or presence of water molecules in the copper coordination sphere results, respectively, in the enhancement or suppression of antiferromagnetic interactions between Cu[SUP2+] ions. Analysis of the EPR spectra shows considerable temperature dependence of both the g values and EPR linewidths that persist in the paramagnetic regime for both complexes. Such variation of EPR parameters is attributed to the interplay of demagnetizing field effects, pertinent to the purely paramagnetic compound, and to the presence of short-range magnetic order that applies to the antiferromagnetic polyamine complex. [ABSTRACT FROM AUTHOR]

Background Identifying colorectal cancer associated risks is important for conducting a program for the survey and prevention of colorectal cancer. Aim To investigate the association between use of insulin or metformin with colorectal cancer (CRC) in type 2 diabetes (T2DM). Design Population-based cohort study. Methods Through analysis of National Health Insurance (NHI) database between 1998 and 2010 in Taiwan, we identified 66 324 T2DM patients aged ≥ 20 years and selected subjects without diabetes by 1: 1 randomly matching with the study cohort based on age, sex and index date. We followed up the participants until 31 December 2011 or when they withdrew from the NHI program. Results Compared with non-diabetic subjects, the T2DM patients exhibited an increased risk of CRC [adjusted HR (aHR) = 1.56, 95% confidence interval (CI) = 1.39–1.75], after adjustment for age, sex, urbanization level, comorbidities and examinations of colonoscopy, sigmoidoscopy, or stool occult blood test. Among the T2DM patients, insulin usage increased the risk of CRC (aHR = 1.86, 95% CI = 1.58–0–2.19) after adjustment for age, sex, urbanization level, comorbidities, metformin usage and examinations; nevertheless, metformin decreased the risk of CRC (aHR = 0.65, 95% CI = 0.54–0.77) after adjustment for age, sex, urbanization level, comorbidities, insulin usage and examinations. Compared with the non-insulin cohort, the risk of CRC tended to increase with the incremental dosage of insulin exposure. Conclusion Our population-based cohort study demonstrated an association between T2DM and CRC. Among the T2DM patients, insulin use was associated with an increased risk of CRC and metformin use was associated with a decreased risk of CRC. Inability to obtain information on several potential confounding factors, such as lifestyle and dietary habits, is the major limitation of the study. [ABSTRACT FROM AUTHOR]

Aim To evaluate the relationship between dipeptidyl peptidase-4 inhibitor (DPP4i) treatment and chronic rhinosinusitis (CRS) in diabetic patients. Methods We used the Longitudinal Health Insurance Database for this population-based and population-matched cohort design study. Chi-square and Wilcoxon rank-sum tests were used to evaluate the association between categorical and continuous variables, respectively. The Kaplan–Meier method with the log-rank test was used to estimate the risk of CRS and DPP4i users. Results A total of 6198 diabetic patients were included in this cohort study. DPP4i users had a lower risk of developing CRS. The risk of CRS was significantly lower in women, patients with a Diabetes Complications Severity Index score higher than 4, patients with comorbidities, and patients with higher cumulative defined daily dose in the DPP4i group. Conclusion The results of our study demonstrate that the use of DPP4i treatment could decrease CRS risk in diabetic patients in Taiwan. [ABSTRACT FROM AUTHOR]

The most critical parameters for the efficient design of coal processing operations depend on the assessment of coal breakage and washability characteristics of the coal resource. X-ray computed tomography (XCT) technology has been demonstrated to have the capability of analyzing washability and fragmentation parameters (particle size, energy, coal type). In this regard, progeny size distributions are obtained from sequential modified drop shatter tests (different input energy levels) and from XCT analysis. In this way, the breakage characteristics (selection and breakage functions) of coal particles are established and the prediction of particle size distribution (PSD) for different levels of energy input is demonstrated. [ABSTRACT FROM AUTHOR]

InAs/GaSb superlattices sandwiched between conventional InAs layers were grown by low pressure metal organic chemical vapor deposition. Period and roughness of the superlattices were examined by field emission transmission electron microscopy. Room temperature infrared absorption spectra for InAs/GaSb superlattices were obtained by Fourier-transform infrared spectroscopy. The effects of varying the doping levels and thicknesses of the InAs sandwiching layers on the absorption spectra of InAs/GaSb superlattices were studied. It was found that by choice of suitable doping levels and cap/buffer thicknesses, the resulting fermi level equalization (as in normal homo or heterojunctions) thereby allowed the setting or “pinning” of the superlattice Fermi level to any desired value within the range made available by the original bulk material characteristics in conjunction with the doping conditions. When the thicknesses of the InAs sandwiching layers became less than 1 μm, the sandwiching effect and the intersubband transition decreased dramatically. The structure of the interfaces inside the superlattice was also studied. Energy dispersive spectroscopy was used to estimate interdiffusion conditions within the superlattice. The effects of different periods and purge gases on the absorption spectra were also studied. [ABSTRACT FROM AUTHOR]

Low pressure fast flow measurements of the emission from CF2(3B1) generated in mixtures of O with C2F4 in Ar and similar measurements using the air afterglow to follow oxygen atoms were made. From measurements of the exponential decay of air afterglow emission, it is concluded that the reaction proceeds through a C2F4O* intermediary. From the intensity and time evolution of the CF2(3B1) emission it is found, contrary to existing belief, that the yield of CF2(3B1) is small (less than 1%) and its radiative lifetime is much shorter than 1 s. The overall loss of O atoms at low C2F4 densities is characterized by a rate constant of 1.2×10-12 cm3 s-1. Both NO and O2 strongly quench the CF2(3B1) while quenching the precursor much less effectively. C2F4 quenches the precursor regenerating O, but does not quench CF2(3B1) significantly. [ABSTRACT FROM AUTHOR]

The collisional quenching of NF(b 1Σ) by F2, IF, and I2 has been studied over the temperature range of 330 through 572 K. The extent of reaction was monitored by measurement of the emission intensity in the b→X transition near 529 nm. A laser-induced fluorescence technique was used to monitor the concentration of the transient species IF and to estimate the gas temperature. Essentially, the data shows that IF and I2 reactively quench NF(b 1Σ) at a gas kinetic rate proportional to T1/2 while F2 quenches less effectively by a factor of 20. At 300 K, the rate constants are 1.2×10-10, 1.4×10-10, and 4.4×10-12 cm3 s-1 for IF, I2, and F2, respectively. These results are correlated with the results of others to give estimates of the product branching ratio for formation of the electronically excited halogen molecules at elevated temperatures. [ABSTRACT FROM AUTHOR]

An efficient predictive model is proposed for analysing the throughput rate of balanced serial production lines where all stations are identical and buffers between stations have the same capacity. The predictive model is based on the simulation data. The experimental design and analysis technique is used to conduct the simulation experiments and the regression analysis method is used to build the predictive model. The model can be applied to a wide range of values in terms of the coefficient of variation of processing times at stations, the buffer size between stations and the number of stations in a system. Comparisons are made with simulation results and previous works. The model can also be extended to account for situations where different stations have different coefficients of variation of processing times. [ABSTRACT FROM AUTHOR]

Here an efficient approximation method is proposed to evaluate the throughput rate of unbalanced serial production lines. The approximation method analyses successive pairs of adjacent stations, and then the solution of a previous two-station system is used in the analysis of the next pair. A number of experiments were performed by simulation for the two-station system. Predictive models of the throughput and the coefficient of variation of interdeparture times for the two- station system have been derived from regression analysis. The line throughput rate of a larger system can be evaluated by repetitively applying these models. Numerical results show that the proposed method works very well even for long production lines. Based on these results, the problem of buffer capacity design is also discussed. Dynamic programming algorithms are proposed to determine the minimum number of total buffer units required and to provide guidelines for buffer allocation to achieve a given target throughput rate. [ABSTRACT FROM AUTHOR]

Discusses a study on the control of the in-plane epitaxy for bi-epitaxial grain boundary junctions using a new multilayer structure. Details of the experimental procedures; Density of the junctions made on the boundary; Current-voltage characteristics of the junctions.

Presents a study which characterized the microstructures of a textured bulk YBa[sub2]Cu[sub3] superconductor using x-ray diffraction, polarized optical microscopy and scanning electron microscopy. Experimental details; Results and discussion; Conclusions.

The velocity fields of nonpremixed circular-disk stabilized flames are measured by a two-component laser Doppler velocimeter. The results are presented in different flow regimes: prepenetration, penetration, and large shear flow. The velocity-vector fields, streamline patterns, corresponding flame appearances, and axial length of recirculation bubble in different flow regimes are illustrated and compared. Mean velocity and turbulent stresses along the central axis are presented and discussed. The combustion characteristics in different characteristic flow regimes are presented through the discussion of entrainment, diffusion, mixing capabilities, flow patterns, and turbulence properties. The detached flames, particularly operating in the transition flow regime, offer a relatively efficient combustion situation. Operating the concentric-jets burner in the regime of high shear flow do not benefit mixing and flame stability through the bluff-body effect. [S0195-0738(00)00102-3]