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Antiviral drugs are among the most common and important classes of pharmaceuticals to treat viral infections, however their continuous emission and persistence in the receiving environment has attracted increasing attention about their potential ecological risks. Here we investigated the occurrence, fate and mass load of 9 antiviral drugs for acquired immunodeficiency syndrome and hepatitis B, in 7 wastewater treatment plants (WWTPs) with different treatment processes in Guangdong, China. Totally, 8 target antiviral drugs were detected in the WWTPs influent wastewater, effluent wastewater and sludge, with maximal concentrations up to 7624 ng/L (telbivudine), 568 ng/L (telbivudine), and 2013 ng/g wet weight (telbivudine), respectively. The removal efficiency varied widely between different antiviral drugs, with the mean aqueous removal efficiency and total removal efficiency ranging from -6.2% (nevirapine) to 100% (lamivudine) and -1.2% (nevirapine) to 100% (lamivudine), respectively. Mass balance analysis showed that their elimination was mostly attributed to the biodegradation/biotransformation. The total back-estimated usage and emission of 9 target antiviral drugs were 77.8 t/y and 13.2 t/y in Guangdong province, China, respectively. Based on the sewage epidemiology approach, the consumption and emission of antiviral drugs in seven studied WWTPs were ranged at 2.31 mg/d/1000 people (nevirapine) to 4970 mg/d/1000 people (telbivudine), and 0 (lamivudine) to 900 mg/d/1000 people (telbivudine), respectively. Preliminary risk assessment showed that the antiviral drugs of zidovudine, ritonavir, lopinavir, and telbivudine in the receiving rivers could pose high ecological risks for aquatic environment. The findings from the present study illustrate the persistence of nevirapine in WWTPs, and provide essential evidence for further study into the development of wastewater treatment technologies.

Background Low-dose amitriptyline (AMT) is an effective treatment for diarrhea-dominant irritable bowel syndrome (IBS-D). Its efficacy depends upon its serum concentration and the patient's CYP2C19 genotype. Aims To identify the association between serum AMT and nortriptyline (NT) concentration and CYP2C19 polymorphism and the clinical response in IBS-D patients. Methods Ninety IBS-D patients were treated of AMT for 6 weeks. Efficacy was evaluated by the results of the Adequate Relief question each week and an IBS severity scoring system (IBS-SSS) at 0, 3, and 6 weeks. CYP2C19 genotyping was performed by direct sequencing. AMT and NT steady-state serum concentrations were detected by high-performance liquid chromatography. Results The CYP2C19 polymorphism exhibited a significant influence on the NT serum concentration but did not predict the clinical efficacy of AMT for treating IBS-D. The NT steady-state and dose-corrected serum concentrations were significantly correlated with an improvement in the IBS-SSS score after 6 weeks, whereas the AMT serum concentration was not correlated with clinical improvement. The cut-off NT steady-state serum concentration of 2.91 ng/ml may help distinguish responders from non-responders. Conclusions NT serum concentration but not CYP2C19 polymorphism may be correlated with the clinical efficacy of AMT for treating IBS-D, and such a response may occur at the upper NT threshold of 2.91 ng/ml.

The long term evolution (LTE) based smart grid communication network is a promising candidate solution for the future power grid. In this paper, we discuss three channel estimation schemes for the LTE-based smart grids, including least square (LS), minimum mean square error (MMSE), and discrete Fourier transform (DFT) based channel estimators. In the simulations, we compare these three estimators, the results show that the DFT-based channel estimator can achieve the best tradeoff between the performance and the implementation complexity.

We demonstrate generation of high-power and large-energy noise-like square pulses at 1612 nm in an all-fiber dumbbell-shaped mode-locked Er: Yb co-doped double-clad fiber (EYDF) laser. The custom couplers with high power handling keep the laser function well. Large-mode-area EYDF with high power handling and enough high pump power make it possible to obtain high output power in the oscillator. Compared with figure-eight structure, strictly all-fiber dumbbell-shaped structure without isolator and optimizing splicing loss could reduce intra-cavity loss and improve optical to optical efficiency, which could reduce heat accumulation and enhance the power carrying capacity of EYDF. In order to study the influence of in-band absorption on output wavelength, EYDF1 and EYDF2 with different in-band absorption coefficients are accessed to intracavity, respectively. It is directly demonstrated that regulation of in-band absorption is an effective way to control the output wavelength. Strong in-band absorption could restrain the emission of C-band and make the wavelength range above 1.6 μm obtain enough gain. Linear insertion loss is another important factor to affect the emission wavelength in EYDF fiber laser. At pump power of 8 W, maximum average output power with emission wavelength above 1.6 μm can reach 1.16 W, corresponding to a single pulse energy of 1.26 μJ. SNR of output pulse is 70 dB which indicates the high stability of mode-locking. In order to verify and evaluate influence of insertion loss on the output characteristics of mode-locked laser, a variable attenuator is inserted in experimental setup, allowing us adjust the linear loss of the cavity. By increasing pump power and adjusting PCs, mode-locked pulses could be obtained on the condition of large additional insertion loss. Even though ~ 10 dB additional insertion loss is introduced, the oscillation still could function at 1612 nm and keep stable mode-locked state. This result demonstrates our oscillation could bear strong additional loss and own strong robustness. If excessively large additional insertion loss is added, 1566 nm becomes the central emission wavelength and wavelength component at 1612 nm almost disappears. Our investigation supplies a direct guideline to design high-power fiber laser with emission wavelength above 1.6 μm.

Purpose We aimed to assess the safety and efficacy of preoperative intensity-modulated radiotherapy (IMRT) with oral capecitabine in patients with locally advanced mid-low rectal cancer using a concomitant boost technique. Materials and methods Patients with resectable locally advanced mid-low rectal cancer (node-negative ⩾T3 or any node-positive tumor) were eligible. The eligible patients received IMRT to 2 dose levels simultaneously (50.6 and 41.8Gy in 22 fractions) with concurrent capecitabine 825mg/m 2 twice daily 5days/week. The primary end point included toxicity, postoperative complication, and pathological complete response rate (ypCR). The secondary endpoints included local recurrence rate, progression-free survival (PFS), and overall survival (OS). Results Sixty-three eligible patients were enrolled; five patients did not undergo surgery. Of the 58 patients evaluable for pathologic response, the ypCR rate was 31.0% (95% CI 19.1–42.9). Grade 3 toxicities included diarrhea (9.5%), radiation dermatitis (3.2%), and neutropenia (1.6%). There was no Grade 4 toxicity reported. Four (6.9%) patients developed postoperative complications. Two-year local recurrence rate, PFS, and OS were 5.7%, 90.5%, and 96.0%, respectively. Conclusions The design of preoperative concurrent boost IMRT with oral capecitabine could achieve high rate of ypCR with an acceptable toxicity profile.

The computation and evaluation of color difference for images is a hot topic. In order to explore the calculation method of evaluating color difference sensation for similar images, 68 pairs of test images were made, which were made from ISO SCID 400 color images by altering their lightness and chroma respectively to cause different color difference scales, and tested by psychophysical experiment. The experiment results showed that the calculated color difference by each formula had a relation to the color difference sensation and the color difference formulae were optimized based on the experimental data.