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Arithmetic bit-interleaved coded modulation (A-BICM) is a coded rate compatible modulation (RCM). It achieves progressive mapping to strike a trade-off between high signal-to-noise ratio (SNR) and low SNR. However, the weights for parity bits are random and not sufficient, which decreases the performance significantly. In order to address the problem, this paper proposes a novel weight mapping scheme for A-BICM. The proposed scheme aims to design the degree and the weight distribution in the mapping matrix to decrease the error probability of parity bits. Through analysis, we have found that the proposed scheme is beneficial to increase the minimum Euclidean distance of symbols. Through simulation, the proposed scheme is verified to increase the throughput of transmission and decrease the demapping complexity at the same time. Both analysis and simulation results show that the proposed scheme outperforms the original A-BICM.

Rate compatible modulation is a novel adaptive transmission technology that does not require channel state information feedback, can achieve rate adaptive adjustment, and smoothly approach channel capacity. However, due to the nature of incremental decoding, the decoding complexity is too high and the transmission performance is reduced under bad channel conditions. Based on the feature of the systematic Polar code that separates the information bits and the check bits, this paper optimizes the design of the hybrid cascade of the systematic Polar code and rate-compatible modulation, and proposes a feasible scheme for adjusting the corresponding weight of check bits. The simulation results show that the proposed scheme can achieve better transmission performance in a wider range of signal-to-noise ratio with relatively lower decoding overhead.

Rate-compatible modulation (RCM) can achieve adaptive transmission in a variable channel environment. However, there are two problems with conventional RCM. Firstly, there is a large number of four rings in the mapping matrix of the conventional RCM, which blocks the delivery of messages in the decoding. Secondly, in the conventional decoding of RCM, the soft information of the last decoding will be discarded when cyclic redundancy check (CRC) is failed, which decreases the performance significantly. In order to address these two problems, in this paper, we propose a new method to construct a mapping matrix without four rings (MMwoFR) and an improved belief propagation (IBP) algorithm for RCM decoding. On the one hand, by using MMwoFR, the constructed matrix is able to prevent the existence of four rings which have much side influence of reliability performance. On the other hand, the IBP is able to make the most use of the soft information in RCM decoding. Simulation results show that using MMwoFR and IBP can bring at least 12% goodput gain for RCM at the high signal-to-noise ratio (SNR) region while maintaining the same performance in the low and moderate SNR regions. Moreover, complexity analysis shows that the new scheme has comparable complexity compared with a conventional RCM.

Based on the catalytic activity of hemin, an efficient biocatalyst, an indirect capillary electrophoresis–chemiluminescence (CE-CL) detection method for phenols using a hemin–luminol–hydrogen peroxide system was developed. Through a series of static injection experiments, hemin was found to perform best in a neutral solution rather than an acidic or alkaline medium. Although halide ions such as Br− and F− could further enhance the CL signal catalyzed by hemin, it is difficult to apply these conditions to this CE-CL detection system because of the self-polymerization of hemin, as it hinders the CE process. The addition of concentrated ammonium hydroxide to an aqueous/dimethyl sulfoxide solution of hemin–luminol afforded a stable CE-CL baseline. The indirect CE-CL detection of five phenols using this method gave the following limits of detections: 4.8 × 10−8 mol/L (o-sec-butylphenol), 4.9 × 10−8 mol/L (o-cresol), 5.4 × 10−8 mol/L (m-cresol), 5.3 × 10−8 mol/L (2,4-dichlorophenol) and 7.1 × 10−8 mol/L (phenol). Copyright © 2013 John Wiley & Sons, Ltd.

A simple and effective capillary electrophoresis–chemiluminescence (CE–CL) detection system was developed based on an ultra-fast bis(2,4,6-trichlorophenyl)oxalate (TCPO) chemiluminescence (CL) reaction (0.6 s duration) that avoided overlapping peaks and peak tailing. Through a series of static injection experiments, this unusually rapid CL reaction was ascribed to the catalytic effect of imidazole in the tetrahydrofuran solvent, which has been rarely utilized in such investigations. A possible mechanism is given to explain the results. Under the optimized conditions, rhodamine 6 G (R6G) and its hydrolysis product (R6G-COOH) could be efficiently separated through electrophoresis in 7 min, with sensitive CL detection in the proposed CE–CL system. In this way, the alkaline hydrolysis of R6G was monitored, followed by estimation of relative rate constants and activation energy. This finding and application should be helpful in further study for the TCPO CL reaction, and revealed an attractive opportunity for simplifying the CE–CL system, such as in a microchip device. Copyright © 2011 John Wiley & Sons, Ltd.

The aggregation and adhesion of bacterial cells is a serious disadvantage for electrophoretic separations of bacteria. In this study, lipid-based liquid crystalline nanoparticles were used as a pseudostationary phase to minimise the bacterial aggregation and adsorption to the inner walls of microchannels. Lactobacillus delbrueckii subsp. bulgaricus, Streptococcus thermophilus and Lactobacillus rhamnosus were selected as analytes and were separated by microchip electrophoresis (MCE) with laser-induced fluorescence (LIF) detection using 4.5 mM tris(hydroxymethyl) aminomethane (TRIS)–4.5 mM boric acid–0.1 mM ethylenediaminetetraacetate (EDTA) (TBE) containing poly(ethylene oxide) (PEO) and lipid-based nanoparticles as the running buffer. The mechanism of lipid-based nanoparticles affecting bacterial adhesion and aggregation was discussed and supported by zeta potential experiments. Under the optimal conditions, the three species of bacteria were identified with patterned peaks. This proposed MCE method using lipid-based nanoparticles as running buffer additives was also used to analyse a real yogurt sample, and valuable bacterial information was obtained by the electropherograms.

With a view of simultaneous determination of physio-active ingredients in oolong tea infusion: sugars, amino acids, epigallocatechin gallate and ascorbic acid, a novel CZE with amperometric detection method was studied. Operated in a wall-jet configuration, 100 mmol/L NaOH was used in detecting cell to lead the electrocatalysis oxidation behaviors of the analytes on a 300 mum diameter copper-disc electrode (working electrode), while in separating capillary, a mild alkaline running buffer consisting in a mixture of 30 mmol/L borate and 40 mmol/L phosphates charged and carried analytes to detecting end. The methodology research was performed for system stability and suitability. Under the optimal CE conditions, analytes could be separated within moderate time period. Good linearity between peak area and concentration existed over three orders of magnitude; lower RSD and LOD were achieved. The oolong tea infusion was assayed and result was satisfactory.

As a kinetic process, chemiluminescence (CL) met great challenges while it was used in the detection methods coupled with capillary electrophoresis (CE). In this investigation, a newly recorded ultra-fast CL reaction of luminol–KIO4–K3Fe(CN)6 was observed to be completed in 0.65 s. It was adopted in a simple CE-CL system efficiently to avoid the peak-tailing and overlapping. With this compact system, an indirect determination of rhamnose, d -fructose, sucrose and β-cyclodextrin was realized based on the corresponding negative CL peaks. These peaks were due to the displacement of luminol anions by the analyzed saccharide molecules in alkaline separation electrolyte. In this way, these four saccharides could be separated and determined in 16 min with adequate sensitivities and stabilities. No derivatization or pretreatment was required for the analysis, and it presents an attractive opportunity for routine tests of mono-, di- and oligo-saccharides in a compact CE-CL system, even as a microchip device.

A simple and effective capillary electrophoresis-chemiluminescence (CE-CL) detection system was developed based on an ultra-fast bis(2,4,6-trichlorophenyl)oxalate (TCPO) chemiluminescence (CL) reaction (0.6 s duration) that avoided overlapping peaks and peak tailing. Through a series of static injection experiments, this unusually rapid CL reaction was ascribed to the catalytic effect of imidazole in the tetrahydrofuran solvent, which has been rarely utilized in such investigations. A possible mechanism is given to explain the results. Under the optimized conditions, rhodamine 6 G (R6G) and its hydrolysis product (R6G-COOH) could be efficiently separated through electrophoresis in 7 min, with sensitive CL detection in the proposed CE-CL system. In this way, the alkaline hydrolysis of R6G was monitored, followed by estimation of relative rate constants and activation energy. This finding and application should be helpful in further study for the TCPO CL reaction, and revealed an attractive opportunity for simplifying the CE-CL system, such as in a microchip device.

Numerous evidence demonstrate Type 1 diabetes (T1D) is due to a loss of immune tolerance to islet antigens, and CD8 + T cells play an important role in the development of T1D in NOD mice. The novel coinhibitory receptor BTLA may have a regulatory role in maintaining peripheral tolerance, however, its role in autoimmune diabetes is unknown. To explore whether the generation of tolerance aiming at BTLA will help therapeutic intervention in T1D, the NOD mice were treated with genetically modified dendritic cells (DCs) expressing BTLA. The results demonstrated that transfer of modified DCs significantly induced CD8 + T cell tolerance and attenuated the severity of diabetes. The findings suggest that genetically modified DC therapies enhancing the BTLA negative cosignal may prove valuable in treating T1D and other autoimmune diseases.