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This study was to elucidate longitudinally quantitative changes of hepatitis B virus (HBV) surface antigen (HBsAg) and HBV DNA in elder HBsAg carriers in a community. Among 1002 residents screened for HBsAg in 2005, 405 responded to this follow-up study in 2010. Fifty-nine (14.6%) were HBsAg carriers in 2005; HBsAg quantification and HBV DNA were measured. HBsAg quantification (cutoff 1600 IU/mL) and HBV DNA (cutoff 2000 IU/mL) were combined to stratify the participants between two screens. A total of 30 men and 29 women with a mean age of 63.9 ± 7.9 years were enrolled. Quantitative levels of HBsAg and HBV DNA were significantly correlated in 2005 (r = 0.509, p 0.001) and 2010 (r = 0.777, p 0.001). Concentrations of HBsAg (IU/mL) significantly decreased from 2.2 ± 1.0 log in 2005 to 1.7 ± 1.5 log in 2010 ( p 0.001). The level of HBsAg was decreased in 48 (81.4%) individuals and HBsAg was undetectable in eight (13.6%). The annual incidence of HBsAg clearance was 2.7%. These 59 HBsAg carriers in 2005 were divided into four groups: low HBsAg low HBV DNA ( n = 32), high HBsAg low HBV DNA ( n = 5), low HBsAg high HBV DNA ( n = 12) and high HBsAg high HBV DNA ( n = 10). All 32 individuals in the low HBsAg low HBV DNA group were still in that group in 2010, whereas only two of the high HBsAg high HBV DNA group became inactive. As with a younger cohort in hospital, HBsAg quantification was still well correlated with HBV DNA in elderly HBsAg carriers in the community. Lower levels of both HBsAg and HBV DNA might represent an inactive HBV infection.

Two genes are called synthetic lethal (SL) if their simultaneous mutations lead to cell death, but each individual mutation does not. Targeting SL partners of mutated cancer genes can kill cancer cells specifically, but leave normal cells intact. We present an integrated approach to uncovering SL pairs in colorectal cancer (CRC). Screening verified SL pairs using microarray gene expression data of cancerous and normal tissues, we first identified potential functionally relevant (simultaneously differentially expressed) gene pairs. From the top-ranked pairs, ~20 genes were chosen for immunohistochemistry (IHC) staining in 171 CRC patients. To find novel SL pairs, all 169 combined pairs from the individual IHC were synergistically correlated to five clinicopathological features, e.g. overall survival. Of the 11 predicted SL pairs, MSH2-POLB and CSNK1E-MYC were consistent with literature, and we validated the top two pairs, CSNK1E-TP53 and CTNNB1-TP53 using RNAi knockdown and small molecule inhibitors of CSNK1E in isogenic HCT-116 and RKO cells. Furthermore, synthetic lethality of CSNK1E and TP53 was verified in mouse model. Importantly, multivariate analysis revealed that CSNK1E-P53, CTNNB1-P53, MSH2-RB1, and BRCA1-WNT5A were independent prognosis markers from stage, with CSNK1E-P53 applicable to early-stage and the remaining three throughout all stages. Our findings suggest that CSNK1E is a promising target for TP53-mutant CRC patients which constitute ~40% to 50% of patients, while to date safety regarding inhibition of TP53 is controversial. Thus the integrated approach is useful in finding novel SL pairs for cancer therapeutics, and it is readily accessible and applicable to other cancers.

A Bayesian approach is considered to detect the number of change points in simple linear regression models. A normal-gamma empirical prior for the regression parameters based on maximum likelihood estimator (MLE) is employed in the analysis. Under mild conditions, consistency for the number of change points and boundedness between the estimated location and the true location of the change points are established. The Bayesian approach to the detection of the number of change points is suitable whether the switching simple regression is continuous or discontinuous. Some simulation results are given to confirm the accuracy of the proposed estimator.

The development of pedestrian detection techniques mainly focused on the research on suitable visual feature in the past decades. However, illumination is not only important to human visual ability to view the surroundings, but is also very critical to the choice of visual features in the vision-based detection methods. Since the visual information can be greatly affected by different illuminations, the resulting detection methods can produce unreliable results. Image-Range Fusion System (IRFS) is proposed by applying the image data from a camera and the range data from a radar simultaneously. For the image part, Logarithm Weighted Pattern (LWP) and a Dynamically Illuminated Object (DIO) detector is proposed to overcome the possible problem caused by the uncertain partial lighting condition within a low-illumination environment. To validate our results, several experiments have been conducted, and the overall system performance is shown to be 88.69%/82.81% of recall/ precision under real-time computing setting.

The optical polarization of GaN/AlGaN wurtzite quantum wells in various orientations is studied using an arbitrarily-oriented [ h k i l ] Hamiltonian potential matrix. The optical matrix elements in the wurtzite quantum wells are calculated using the k ⋅ p finite difference scheme. The results reveal the presence of giant in-plane optical anisotropy (polarized normal to [0001]) in the M-plane (i.e., the ( 10 1 ¯ 0 ) -oriented layer plane) GaN/Al0.2Ga0.8N quantum well, due to the positive crystal-field split energy effect ( Δ CR > 0 ). The present theoretical results are consistent with the photoluminescence measurements presented in the literature [B. Rau, et al., Appl. Phys. Lett. 77 (2000) 3343].

A new hepatitis C virus (HCV) core antigen (HCV Ag) assay was thought to have a good correlation with HCV RNA. The aim was to elucidate the usefulness of this HCV Ag assay in community screening. In a township where HCV is endemic, 405 residents aged 58 years or older responded to a follow-up community screening. All subjects were tested for anti-HCV (AxSYM, version 3.0; Abbott Diagnostics) and HCV Ag (Architect HCV Ag test; Abbott Diagnostics). For subjects with anti-HCV signal-to-cutoff ratios (S/CO) > 10 and/or HCV Ag > 3 fmol/liter, HCV RNA data (Taqman HCV RNA; Roche Diagnostics) were further checked. A total of 115 (28.4%) subjects had their serum HCV RNA levels measured, and 93 were HCV RNA positive. The other 290 subjects were supposed to be HCV RNA negative. HCV Ag was significantly correlated with HCV RNA according to the following equation: (log HCV RNA) = 2.08 + 1.03 (log HCV Ag) ( R 2 = 0.94; P < 0.001). As determined using a combination of the values for anti-HCV (S/CO > 40) and HCV Ag (>3 fmol/liter) as a cutoff to predict viremia, the sensitivity, specificity, accuracy, positive predictive value, and negative predictive value were 96.8%, 100%, 99.3%, 100%, and 99%, respectively. In conclusion, for a community study, HCV Ag showed good correlation with HCV RNA. In addition, anti-HCV or HCV Ag can predict HCV viremia well, while a combination of anti-HCV (>40 S/CO) and HCV Ag (>3 fmol/liter) can provide the best result validity.

A modeling framework is proposed to assess the detrimental effects of air sparging and other bubble phenomena (vortex entrainment, coalescence, bursting) on freely suspended cells in an aerated, agitated bioreactor. It is assumed that cells may be rendered nonviable by bubble breakup/coalescence within the medium, by bubble formation at the sparger, or by bubble bursting at the free surface. Some plausible mechanisms are argued from the energetic view point. The dominant parameters in each case are the cell-bubble encounter rate and the bubble breakup/bursting rate. These inactivation processes lead to a Michaelis-Menten expression for the specific cell death rate, which is shown to be linearly proportional to the specific bubble interfacial area (total bubble surface area per unit volume of media). By using published viable cell concentration data for retarded growth of mammalian cells due to sparging, the interfacial area correlation is demonstrated. The method is generalized to aerated bioreactor conditions. The article offers a unique, consistent perspective on how cell death can be viewed.

Diglycidyl ether of Tetrabromobisphenol A (DGETBA) is mainly for making copper clad laminate (CCL), which is the base of printed circuit board (PCB) in Taiwan. If not properly treated and disposed, waste printed circuit board would make the already polluted environment worse. The objective of this study is to pursue the chemical reaction kinetics for pyrolysis of DGETBA by molten salt. The molten salt used in this study composed of Sodium-nitrate (NaNO3) and Sodium-nitrite (NaNO2) with the ratio of 4:1. The following reaction rate equation has been obtained: dC/dt= -kC0.7, where k is the reaction rate constant, C is the reactant concentration, t is the reaction time, and which can further be obtained as follows: k=ATbexp (-E/RT)=33.9×T0.00034 exp (-2118/1.987T), where A is a frequency factor (1/s), b is a empirical parameter temperature function, E is the activation energy (cal/mol), R is universal gas constant (1.987 cal/mol K), andT is the reaction temperature (K). Key words: Diglycidyl ether of tetrabromobisphenol A (DGETBA), printed circuit board (PCB), kinetics, pyrolysis, molten salt.

In multiple change-points model, the dynamic programming (DP) algorithm can be use to obtain the maximum likelihood estimation for a sequence of data from multivariate normal distribution. Since the algorithm has a quadratic complexity in data size n, it is computationally burdensome if the data size n is large. In this paper we present a fast two-stage dynamic programming (TSDP) through the window method. In TSDP algorithm, the first stage is to use the window method based on the log-likelihood ratio measure to find a subset of candidate change points. The second stage is to apply DP algorithm on the chosen subset to detect the position of change points. The proposed algorithm of change-points will be used for the boundary detection of speech signal by finding the abrupt spectral difference change of adjacent frames. Some simulated data sets and the speech data are investigated for DP and TSDP algorithms. In comparison of CPU times, the TSDP algorithm can be up to 34.96 and 74.02 times faster than the DP algorithm for the simulated data and the speech data respectively. The results show that our algorithm works very well. It substantially reduces the computation load for large data size n.

The dynamic programming (DP) algorithm can be used to find an exact solution of the maximum likelihood estimation of change points in a sequence of data from exponential family. Since the algorithm has a quadratic complexity in data size n, it is computationally burdensome if the data size n is large. In this work, a fast two-stage (TS) algorithm by window method is proposed. The window method is simple and interesting. The first stage is to apply the window method based on the log likelihood ratio measure to find a subset of candidate change points, and use DP algorithm on the chosen subset to obtain good initial change points which will be proximate to the locations of the true change points. The second stage is to apply the segmental K-means (SKM) algorithm on the initial change points obtained in the first stage. Some simulated data sets are investigated for DP, SKM and TS three algorithms. We find that, in comparison of CPU times, the SKM algorithm is fastest than DP and TS algorithm with the largest error in the estimation of change points. For TS and DP algorithms, both yield the small errors, but in the speed of CPU times, our TS algorithm can be up to 18.94 times faster than the DP algorithm. The results show that our algorithm works very well. It substantially reduces the computation load for large data size n.

This paper investigates the electrokinetic instability (EKI) phenomenon in a T-type microchannel, in which two aqueous electrolyte solutions with a 10:1 conductivity ratio are driven electrokinetically into the mixing channel via the application of a DC electrical field. It is found that fluctuating, unstable waveforms are formed in the entrance region of the mixing channel and then propagate in the downstream direction when the intensity of the electrical field is increased beyond a certain critical threshold value. Electrical field intensity perturbations aligned in the direction of the conductivity gradient are then added to the DC electrical field at the upper inlet of the T-type microchannel. It is found that the application of the electrical field intensity perturbations induces flow instability conditions, and hence improves the mixing efficiency. Furthermore, these perturbations stir the microfluidic instability and can reduce the required critical threshold value of the applied DC electric field intensity.