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The planting of the vegetation on the floodplain helps the ecological restoration, which is the main form of the river's ecological corridor. Therefore, the current research of the river dynamics focuses on the water movement under a compound channel with the vegetated floodplains. Two simulated vegetation species are selected in this paper for the flume simulation experiments of the floodplain vegetation, and the compound channel is divided into three subregions in the transverse direction. The Navier-Stokes equation and the eddy viscosity theory are applied to obtain the transverse distribution of the depth-averaged velocity and the results agree well with the experimental data. This paper proposes a new method based on the analytical solution of the flow velocity distribution to calculate the average flow velocity in each section. Calculation results can effectively simulate the average flow velocity of the measured sections. The description of the pollutant transport processes in a moving stream requires a refined determination of the dispersion coefficients in the compound channel. The process of the pollutant concentrations in each zone and the reasons for their occurrence are elucidated on the basis of the experimental results. Simultaneously, the measured values of the longitudinal dispersion coefficients are obtained by the "routing procedure," and a two-zone model of the pollutant dispersion is constructed on the basis of the hydrodynamic study. The prediction method for the longitudinal dispersion coefficients is also presented. Applying the predicted and measured section average flow velocities to the two-zone model to predict the longitudinal dispersion coefficient, and the average relative errors are only 4.17%, 7.15%, respectively. This result indicates that the two-zone model can effectively predict the longitudinal dispersion coefficients. The calculation methods for the longitudinal dispersion coefficients from—various studies are compared. The results reveal that the predicted values of these calculation methods are all larger than the measured values, indicating that the vegetation has a considerable influence on the dispersion process. This study comprehensively shows the dispersion features of the pollutants and provides a theoretical basis for the planning and the design of the vegetated ecological corridors. [ABSTRACT FROM AUTHOR]

Purpose: The burden of non-communicable diseases (NCDs) has increased in China. However, the contribution of dietary risks to the NCD burden has not been evaluated. This study aimed to estimate the burden of ischemic heart disease (IHD) and colorectal cancer (CRC) attributable to a diet low in fiber in China from 1990 to 2017. Methods: China data from the Global Burden of Disease Study (GBD) 2017 were used to assess the age-, sex-, and province-specific mortality and disability-adjusted life-years (DALYs) of IHD and CRC related to a diet low in fiber. Results: In 2017, a diet low in fiber contributed 170,143 [95% uncertainty interval (UI): 99,623–256,806] IHD deaths and 25,561 (95% UI: 13,726–39,215) CRC deaths, with the population attributable fractions (PAFs) were 9.7 and 13.7%, respectively. Males had higher risk-attributable mortality and DALY rates for IHD and CRC than females. An upward trend with age in rates of mortality and DALY was observed. All-age risk-attributable mortality and DALY rates increased significantly by 111.4 and 53.2% for IHD, and 94.4 and 59.6% for CRC from 1990 to 2017, respectively; however, the corresponding age-standardized rates for IHD and CRC showed relatively stable trends. Heilongjiang, Xinjiang, and Inner Mongolia were ranked as the top three provinces in terms of total risk-attributable NCD burden in 2017. Conclusions: China has a large and growing NCD burden attributable to a diet low in fiber. Greater priority in disease prevention and control should be given to male and older adults throughout China, particularly in some western provinces. [ABSTRACT FROM AUTHOR]

otrA resembles elongation factor G (EF-G) and is considered to be an oxytetracycline (OTC)-resistance determinant in Streptomyces rimosus. In order to determine whether otrA also conferred resistance to OTC and other aminoglycosides to Streptomyces coelicolor, the otrA gene from S. rimosus M527 was cloned under the control of the strong ermE* promoter. The resulting plasmid, pIB139-otrA, was introduced into S. coelicolor M145 by intergeneric conjugation, yielding the recombinant strain S. coelicolor M145-OA. As expected S. coelicolor M145-OA exhibited higher resistance levels specifically to OTC and aminoglycosides gentamycin, hygromycin, streptomycin, and spectinomycin. However, unexpectedly, S. coelicolor M145-OA on solid medium showed an accelerated aerial mycelia formation, a precocious sporulation, and an enhanced actinorhodin (Act) production. Upon growth in 5-L fermentor, the amount of intra- and extracellular Act production was 6-fold and 2-fold higher, respectively, than that of the original strain. Consistently, reverse transcription polymerase chain reaction (RT-PCR) analysis revealed that the transcriptional level of pathway-specific regulatory gene actII-orf4 was significantly enhanced in S. coelicolor M145-OA compared with in S. coelicolor M145. [ABSTRACT FROM AUTHOR]

A rapid and simple short-end injection microemulsion electrokinetic chromatography (MEEKC) method was developed for the routine analysis of alpinetin and cardamonin in Alpinia katsumadai Hayata in combination with microwave-assisted extraction (MAE). The key parameters affecting separation and extraction were investigated and optimized. The optimal MAE was performed at 800 W for 12 min with 100% ethanol as the extraction solvent, which gave a better extraction efficiency and required a significantly shorter time than conventional heat reflux extraction (HRE) and ultrasonic extraction (USE). When this detection system based on ethyl acetate oil-based MEEKC and short-end injection was applied, the analysis was completed in less than 1.5 min. In the method validation, the relative standard deviations of the migration times and peak areas of the two constituents were 0.74, 1.86% for alpinetin and 0.63, 2.05% for cardamonin, respectively. The recoveries ranged from 94.6 to 105.8%. Compared with previously reported methods, the present method offers a dramatic decrease in overall analysis time, and has the further advantages of easy operation and low running costs. Graphical abstract: [ABSTRACT FROM AUTHOR]

Background: Single-incision laparoscopic surgery (SILS) was developed as a novel minimally invasive surgical approach. Aims: The aim of this meta-analysis was to compare SILS and conventional laparoscopy (CL) for colorectal diseases with respect to perioperative and oncologic outcomes. Methods: An electronic search was performed to retrieve all relevant articles published in the English language between 2008 and 2012 comparing SILS and CL for colorectal diseases. The data were analyzed with fixed-effect or random-effects models using review manager version 5.0. Results: A total of 14 studies (one randomized controlled trial and 13 nonrandomized controlled trials) were found to be eligible and reported on 1,155 subjects, of whom 521 underwent SILS and 634 underwent CL for colorectal diseases. Concerning the perioperative outcomes, no differences were observed in conversion rate, operating time, and postoperative adverse events; however, patients who underwent SILS had lower blood loss, decreased blood transfusion requirement, shorter time to flatus, shorter hospital stay, and smaller incision. Concerning the oncologic outcomes, length of resected specimens, number of harvested lymph nodes, proximal margin, and distal margin, were comparable between two groups. Conclusions: Single-incision laparoscopic surgery (SILS) is a safe, feasible, and oncological efficient alternative to CL for colorectal diseases. Further larger, multi-centred, randomised controlled trial is indicated. [ABSTRACT FROM AUTHOR]

Recently, TiO nanotube layers are widely used in orthopedics and dental applications because of their good promotion effect on bone cells. Furthermore, peptide sequences such as arginine-glycine-aspartic acid are used to modify Ti implant for binding to cell surface integrins through motif. In this study, a cellular adhesive peptide of arginine-glycine-aspartic acid-cysteine (RGDC) was immobilized onto anodized TiO nanotubes on Ti to examine its in vitro responses on rat bone marrow stromal cells (BMSCs). Materials were characterized by scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy techniques. High-resolution C1s scans suggested the presence of RGDC on the surface and SEM images confirmed the nanotubes were not destroyed after modification. BMSCs adhesion and osteogenic gene expression were detected in TiO nanotube layers with and without RGDC modification by fluorescence microscopy, confocal laser scanning microscopy, SEM, and realtime polymerase chain reaction (Real-time PCR). Results showed that the TiO nanotube layers immobilized with RGDC increased BMSCs adhesion compared to nonfunctionalized nanotubes after 4 h of cultivation. Furthermore, the osteogenic gene expression of BMSCs was dramatically enhanced on the TiO nanotube layers immobilized with RGDC (10 mM) compared to the TiO nanotube layers immobilized with RGDC (1 mM) and non-functionalized anodized Ti. Our results from in vitro study provided evidence that Ti anodized to possess nanotubes and then further functionalized with RGDC should be further studied for the design of better biomedical implant surfaces. [ABSTRACT FROM AUTHOR]

Background: Laparoscopic liver resection (LLR) remains to be established as a safe and effective alternative to open liver resection (OLR) for hepatocellular carcinoma (HCC). Aims: The aim of this meta-analysis is to compare laparoscopic versus open resection for HCC with regard to perioperative and oncologic outcomes. Methods: A literature search was performed to identify comparative studies reporting outcomes for both laparoscopic and open resection for HCC. Pooled odds ratios (OR) and weighted mean differences (WMD with 95% confidence intervals (95% CI) were calculated using either the fixed effects model or random effects model. Results: Ten nonrandomized controlled studies matched the selection criteria and reported on 494 subjects, of whom 213 underwent LLR and 281 underwent OLR for HCC. Compared with the perioperative results of open surgery, reports on laparoscopic resection indicate potentially favourable outcomes in terms of operative blood loss (WMD: −160.57, 95% CI: −246.49 to −74.66), blood transfusion requirement (OR: 0.39, 95% CI: 0.18 to 0.86), postoperative morbidity (OR: 0.48, 95% CI: 0.29 to 0.78), and length of hospital stay (WMD: −5.53, 95% CI: −7.89 to −3.16). Concerning the oncologic outcomes, there was no difference between groups in surgical margin, overall survival and disease-free survival. Conclusions: LLR for HCC is superior to the OLR in terms of its perioperative results and does not compromise the oncological outcomes. Therefore, LLR may be an alternative choice for treatment of HCC. [ABSTRACT FROM AUTHOR]

rapid, sensitive and accurate ultra-performance liquid chromatography/tandem mass spectrometry method was developed and validated for the quantitative determination of imidol in rat plasma for the first time. The analyte and internal standard were extracted from plasma by liquid-liquid extraction with diethyl ether. The separation was performed on a BEH C column (50 mm × 2.1 mm, 1.7 μm). The detection was carried out by electrospray ionization mass spectrometry in positive ion mode with multiple reaction monitoring. Linear calibration curves were obtained in the concentration range of 2.5-2,500 ng mL, with the lower limit of quantification of 2.5 ng mL. The intra- and inter-day precision (RSD) values were below 8% and accuracy (RE) was from −7.9 to 6.3%. After strict validation, the method was applied successfully to the pharmacokinetic study of imidol in rats after oral and intravenous administration, respectively. [ABSTRACT FROM AUTHOR]