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Combining the multivariate probit models with the multivariate partially linear single-index models, we propose new semiparametric latent variable models for multivariate ordinal response data. Based on the reversible jump Markov chain Monte Carlo technique, we develop a fully Bayesian method with free-knot splines to analyse the proposed models. To address the problem that the ordinary Gibbs sampler usually converges slowly, we make use of the partial-collapse and parameter-expansion techniques in our algorithm. The proposed methodology are demonstrated by simulated and real data examples. [ABSTRACT FROM AUTHOR]

Three new drimane sesquiterpenoids, 12-hydroxyalbrassitriol (1), drim-8(12)-en-6β,7α, 9α,11-tetraol (2), and drim-68(12)-dien-9α,11-diol (3), along with one known analog albrassitriol (4), were isolated from cultures of the tin mine tailings-associated fungusPenicillium sp.The new structures were determined on the basis of extensive spectroscopic analyses. All compounds were tested for their cytotoxicities against five human cancer cell lines. [ABSTRACT FROM PUBLISHER]

As flow improvers for heavy crude oil, two oil-soluble copolymers (DM-S-VA, DA-S-VA) were successfully synthesized and characterized by1H NMR and GPC. A rich alkyl chain and appropriate molecular weight of copolymer play fundamental role in viscosity reduction of heavy oil. Furthermore, synergistic effect of surfactants on polymers can promote the viscosity reduction, and the best formulation can increase the viscosity reduction rate to 78% to oil A. Comparing with the apparent viscosity of the different heavy oil mixing system in a wide shear rate range (0.1–200 s−1), the results show good stability and viscosity reducing effect. [ABSTRACT FROM AUTHOR]

The four polymers with different contents of alkyl chain (C12–C18), styrene, and vinyl acetate were synthesized and employed as the viscosity reducers for super heavy oils A and B. Compared with the apparent viscosity of heavy oil in a wide share rate range (0–200 s−1) at 50°C, it can be seen that the optimal efficiency could be achieved to reduce viscosity when the polymers have suitable length of alkyl chain in the permeation of small molecules (vinyl acetate). Furthermore, the adaptation of the polymers to different oil samples and application temperature of polymers were also studied. [ABSTRACT FROM PUBLISHER]

Objective: To investigate the associations between obesity and any significant improvements in glycemic control, blood pressure, and lipid targets in Chinese patients with concomitant type 2 diabetes mellitus (T2DM) and hypertension.Methods and Results: A total of 3041 dyslipidemia patients with an average age of 65.7 ± 10.53 years and comorbid conditions of T2DM and hypertension from the DYSlipidemia International Study (DYSIS) - China were included in the present subgroup analysis. Patients' demographic data, medication use, blood glucose, and lipid parameters were analyzed retrospectively. Body mass index (BMI), waist circumference (WC), and waist-to-height ratio (WtHR) differed significantly among participants according to the attainment of treatment targets. Among female patients, significant differences in the rate of target attainment were observed among different WC, WtHR, and BMI quartile groups, whereas no significant differences in goal attainment were found according to WC and WtHR quartiles in male patients. Among the female patients, the results of logistic regression supported a significant association of anthropometric indices and the achievement of targets.Conclusion: A considerable proportion of dyslipidemia patients failed to achieve guideline-recommended targets in China, and this apparent treatment gap was more pronounced among women with central adiposity and patients with an elevated BMI. Based on the limitations of this cross-sectional study, further investigation of the mechanism at the molecular level is necessary. [ABSTRACT FROM AUTHOR]

Based on free-knot splines techniques, we develop a fully Bayesian method to make inference about the autoregressive and functional-coefficient moving-average models, including estimation and prediction. We approximate different functional-coefficients by polynomial splines with different orders to adapt to different smoothness. To make the estimation and prediction robust, we assign heavy-tailed student-tpriors on the coefficients of both the splines and the autoregressive terms. The posterior predictive distribution is derived from a Bayesian model average over all of the possible models. The proposed method is demonstrated by both simulated and real data examples. [ABSTRACT FROM AUTHOR]

Partially linear single-index models play important roles in advanced non-/semi-parametric statistics due to their generality and flexibility. We generalise these models from univariate response to multivariate responses. A Bayesian method with free-knot spline is used to analyse the proposed models, including the estimation and the prediction, and a Metropolis-within-Gibbs sampler is provided for posterior exploration. We also utilise the partially collapsed idea in our algorithm to speed up the convergence. The proposed models and methods of analysis are demonstrated by simulation studies and are applied to a real data set. [ABSTRACT FROM AUTHOR]

As a continuous work to find more epothilone congeners produced by the epothilones A and B producing Sorangium cellulosum strain So0157-2 in the large-scale fermentation (5000 L), we reinvestigated the chemical compositions of the fermentation broth. Consequently, two new epothilone variants (1–2) and one new natural epothilone derivative (3) were isolated from the fermentation broth. Their structures were established as 16-ethyl epothilone B (1), 6-desmethyl-16-hydroxymethyl epothilone C (2) and 20-ethyl epothilone A (3), respectively, by an extensive NMR analysis. [ABSTRACT FROM PUBLISHER]

Background and objective: The treatment of infantile hemangioma must address both the effectiveness of the treatment and have as few adverse events as possible for the patient as a result of the therapy. The intense pulsed light (IPL) source can be useful in this regard in treating infantile hemangioma. IPL with optimal pulse technology (OPT) represents a new generation of IPLs and in this clinical investigation, the efficacy and adverse event profiles of treating infantile hemangiomas with an IPL with OPT will be reviewed. Methods: A total of 62 patients with infantile hemangiomas were included in this clinical trial. The mean age of the patients was 6 months old. The Fitzpatrick skin types for those enrolled was either Type III or Type IV. Each patient was subjected to a treatment protocol which included four to five IPL treatments at 4-week intervals. The patients were then assessed at 3 months following their last IPL treatment and clinical improvement was determined by comparisons of pre- and post-therapy photographs. The parents of the patients were asked to score their overall satisfaction with the treatments. Results: From the clinical trial presented, 76% of the infantile hemangiomas were noted to improve with great satisfaction in this clinical trial. A clearance rate of more than 80% was observed. Adverse events, as a result of the IPL treatment, was minimal with less than 5% of the treatments resulting in an adverse event, all of which were noted to be transient in nature. No scarring or pigmentary disturbances were seen in any of the patients evaluated. Conclusions: This new generation IPL with OPT can be considered a safe and effective modality for the treatment of infantile hemangioma. Marked improvement was noted in the majority of study patients and adverse events were noted to be minimal. [ABSTRACT FROM AUTHOR]

It is a standard assumption for regression models that all the random errors are mutually independent and have equal variances. However, in some situations, the assumption is untenable. Tsai (Tsai, C. L. (1986). Score test for the first-order autoregreesive model with heteroscedasticity. Biometrika 73:455–460) introduced a composite test for heteroscedasticity and autocorrelation in linear regression models with AR(1) errors. In this article, we extend Tsai's (Tsai, C. L. (1986). Score test for the first-order autoregreesive model with heteroscedasticity. Biometrika 73:455–460) results to more general case. For the underlying model, we consider nonlinear regression rather than the linear one. For the random error, we extend it from AR(1) process to AR(p) process. Moreover, since the random error may behave nonlinearity sometime, we put a bilinear term in it, which is a simple way to indicate the nonlinearity. So we discuss the test of heteroscedasticity, autocorrelation and bilinearity for nonlinear regression with DBL (p, 0, 1) random errors. Several test statistics based on the score test are obtained, and expressed in simple matrix formulas. The simulation study is performed to investigate the powers of the test statistics. [ABSTRACT FROM AUTHOR]