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• The PC-SCMA technology can enhance the performance of communication system. • JIDD scheme can make full use of the intermediate messages to improve performance. • S-JIDD can effectively reduce complexity and achieve ideal error performance. • Adding CRC early stopping criterion can further reduce the BER of the system. Polar coding and sparse code multiple access (SCMA) technique are excellent candidates for 5G, and have a promising prospect in optical communication, the joint design of polar coded sparse code multiple access (PC-SCMA) system is important to enhance the overall system performance. In this paper, a serial joint iterative detection and decoding scheme is proposed by passing message between serial max-log message passing algorithm and soft cancellation (SCAN) algorithm, the strategy can accelerate the algorithm convergence speed by reducing the number of required iterations, decrease the computational complexity and achieve ideal bit error rate (BER) performance. In order to further improve the BER performance, a cyclic redundancy check (CRC) is added in the joint iterative process as an early stopping criterion to avoid decoding divergence caused by a low signal to noise ratio (SNR). Simulation results demonstrate that the addition of a termination mechanism can obtain an excellent performance gain compares with the conventional JIDD algorithm. [ABSTRACT FROM AUTHOR]

• This AgNO 3 /ionic liquid system employs the lowest level metal loading by far. • This AgNO 3 /ionic liquid system works efficiently under 1 bar of CO 2. • This AgNO 3 /IL system could be recycled and reused for at least 5 times. • The AgNO 3 /IL system green metrics' outperforms all reported Ag-catalyzed cases. • NHC-CO 2 adducts and NHC-Ag complexes were detected during the process. Oxazolidinones and α-hydroxyl ketones are two series of fine chemicals that have been generally utilized in biological, pharmaceutical, and synthetic chemistry. Herein, a AgNO 3 /ionic liquid (IL) catalytic system was developed for the simultaneous synthesis of these compounds through the atom-economical three-component reactions of propargyl alcohols, 2-aminoethanols, and CO 2. Notably, this system behaved excellent catalytic activity with the lowermost metal loading of 0.25 mol%. Meanwhile, it is the first reported metal-catalyzed system that could efficiently work under atmospheric CO 2 pressure and be recycled at least five times. Evaluation of the green metrics proved the AgNO 3 /IL-catalyzed processes to be relatively more sustainable and greener than the other Ag-catalyzed examples. Further mechanistic investigations revealed the derivative active species of N-heterocyclic carbene (NHC) silver complexes and CO 2 adducts generated during the process. Subsequently, their reactivity in this reaction was assessed for the first time, which was finally identified as beneficial for the catalytic activity. [ABSTRACT FROM AUTHOR]

Arsenic is a widely existing pollutant in the environment, but the mechanism of occurrence and development of lung cancer by long-term arsenic exposure needs to be elucidated further. How the high and low doses of arsenic induce human bronchial epithelial cell transformation is yet to be elucidated. In the present study, human bronchial epithelial cells were exposed to varying high-dose sodium arsenite (NaAsO 2) for the short-term or treated with low dose for long-term. The data showed that both short- and long-term treatment promoted G1/S transition of Beas-2B cells, inducing a significant increase in the expression of AKAP95, cyclin D1, cyclin D2, and cyclin E1. However, silencing AKAP95 by treating cells with siAKAP95 exerted a protective function that inhibited G1/S transition, suggesting a regulatory mechanism of AKAP95 on the cell cycle during cell malignant transformation induced by NaAsO 2. In addition, mitochondrial dysfunctions occurred during NaAsO 2 exposure. Beas-2B cells exposed to low-dose NaAsO 2 for long-term were subcultured for 20 generations, and the exposure time was positively proportional to the growth and migration rate of the cells. The exposed cells were used in a tumor-bearing transplantation experiment (mice), and the results showed that the longer the exposure time, the faster the tumor volume growth rate of As-Beas-2B cells. Tumor tissues were excised for hematoxylin-eosin staining, which showed altered cell morphology and increased volume. [Display omitted] • Exposure to arsenic altered the cell cycle of human bronchial epithelial cells. • AKAP95 mediates cell cycle alterations induced by arsenic. • Arsenic exposure causes mitochondrial dysfunction and damage. [ABSTRACT FROM AUTHOR]

Although the accuracy of detecting the expression of miRNAs by quantitative real-time polymerase chain reaction (qRT-PCR) is highly dependent on reliable reference miRNAs, many commonly used reference miRNAs are not stably expressed and as such are not suitable for quantification and normalization of qRT-PCR data. To solve this problem, we analyzed the global expression profiles of thousands of samples in 14 types of common human tumors released by The Cancer Genome Atlas (TCGA), and identified the most stably and highly expressed miRNAs as candidate reference miRNAs in each type of tumor. We found that miR-361-5p and let-7i-5p were the most recommended candidate reference miRNAs in nine and eight types of tumors, respectively, followed by let-7a-5p, mir-28-5p and miR-99b-5p. Our results are of important value to those researchers focused on miRNA; however, these candidate reference miRNAs still need to be validated prior to their use in qRT-PCR studies. [ABSTRACT FROM AUTHOR]

Abstract: The reactions occurred and growth process in the preparation of copper aluminum borate (Cu2Al6B4O17) whiskers based on flux method (Al2(SO4)3/CuSO4/H3BO3 as raw materials, K2SO4 as flux) were investigated. The thermogravimetric and differential scanning calorimetry analysis (TG-DSC), inductively coupled plasma atomic emission spectrum analysis (ICP-AES) and X-ray diffraction analysis (XRD) results of reactants mixture quenched at various temperatures and phase diagrams of K2SO4–Al2(SO4)3 system and B2O3–Al2O3 system showed that the reaction process proceeds through three steps: the formation and decomposition of two different kinds of potassium aluminum sulfate (K 3 Al(SO4)3 and KAl(SO4)2); the formation of aluminum borate (Al4B2O9) and decomposition of copper sulfate (CuSO4) and boric acid (H3BO3); growth and formation of copper aluminum borate (Cu2Al6B4O17) whiskers. The scanning electron microscopy (SEM) analysis results indicated that morphology in growth of Cu2Al6B4O17 whiskers develops through three stages: nanoparticles, fan-shaped whiskers and agminate-needlelike whiskers. [Copyright &y& Elsevier]