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In this paper, we propose a good decoding performance, low-complexity, and high-speed decoder architecture for ultra-long quasi-cyclic LDPC codes by using the layered sum-product decoding scheme. To reduce implementation complexity and hardware resource consumption, the messages in the iteration process are uniformly quantified and the function $\Psi (x)$ is approximated with second-order functions. The decoder architecture improves the decoding throughput by using partial parallel and pipeline structures. A modified construction method of parity check matrices was applied to prevent read&write conflicts and achieve high-speed pipeline structure. The simulation results show that our decoder architecture has good performance at signal-to-noise ratios (SNRs) as low as −0.6 dB. We have implemented our decoder architecture on a Virtex-7 XC7VX690T field programmable gate array (FPGA) device. The implementation results show that the FPGA-based LDPC decoder can achieve throughputs of 108.64 Mb/s and 70.32 Mb/s at SNR of 1.0 dB when the code length is 262,144 and 349,952, respectively. The decoder can find useful applications in those scenarios that require very low SNRs and high throughputs, such as the information reconciliation of continuous-variable quantum key distribution.

In a continuous-variable quantum key distribution (CV-QKD) system, the computation speed of the post-processing procedure, including information reconciliation (IR) and privacy amplification (PA), inevitably affects the practical secret key rate. IR and PA can be implemented in parallel using low-density parity-check (LDPC) codes and hash functions, respectively. We achieve high-speed hardware-accelerated post-processing procedure for Gaussian symbols on a field-programmable gate array (FPGA) by taking advantage of its superior parallel processing ability. To this end, the sum-product algorithm decoders and a modified LDPC codes construction algorithm adapted to FPGA's characteristics are developed and employed. Two different structures including multiplexing and non-multiplexing are designed to achieve the trade-off between the speed and area of FPGAs, so that an optimal scheme can be adopted according to the requirement of a practical system. Simulation results show that the maximum throughput can reach 100 M symbols/s. We verified the correctness of the post-processing procedures when implemented on the Xilinx VC709 evaluation board, which is populated with the Virtex-7 XC7VX690T FPGA and provided some possible solutions to obtain better performance when more advanced FPGAs are available. The scheme can be applied readily for real-time key extraction and effectively reduce power consumption of the CV-QKD system.

INTRODUCTION: Alismatis Rhizoma (AR) has been widely used to treat various diseases. Its complex chemical composition has caused certain difficulties in the analysis of this traditional Chinese medicine. Therefore, it is necessary to establish a method for the rapid classification and identification of the chemical constituents of AR. OBJECTIVE: This article describes a method for the rapid classification and identification of major triterpenoids in AR. METHODOLOGY: The samples were analysed by ultra‐performance liquid chromatography quadrupole time‐of‐flight mass spectrometry (UPLC‐Q‐TOF‐MS). The assay was performed on a Waters ACQUITY UPLC BEH C₁₈ column (100 mm × 2.1 mm, 1.7 μm) with 0.1% formic acid in water (A), and acetonitrile (B) as mobile phase by gradient elution at a flow rate of 0.3 mL/min. In the positive ion mode, the fragment information was obtained and compared with the characteristic fragments and neutral losses described in the literature. Then, the rapid classification and identification of the chemical components from AR were achieved. RESULTS: Finally, 25 triterpene compounds of AR were identified. CONCLUSIONS: The method established in this study achieved the rapid classification and identification of chemical components in AR, which promotes the development of research methods to study the constituents of traditional Chinese medicine.

Breast cancer-related lymphedema (BCRL) is a major long-term complication for post-surgery breast cancer survivors. Although several risk factors have been identified, lifestyle characteristics have been neglected in previous studies. The aim of this study was to develop and validate a nomogram for estimating this population’s risk of developing lymphedema, taking into consideration their demographic, clinical, and personal lifestyle behaviors. In a cross-sectional study, we collected data from 775 post-operative breast cancer survivors who had attended a follow-up session in the recent 10 years (primary cohort). Lymphedema was assessed using the Norman telephone questionnaire, self-reported by patients. Multiple logistic regression was used to identify risk factors for lymphedema, including demographic, clinical, and lifestyle-related factors. A nomogram was constructed based on those factors and was validated using a separate group of 314 breast cancer patients (validation cohort). The factors independently associated with lymphedema were higher body mass index (BMI), modified radical mastectomy (MRM), postsurgical infection, chemotherapy, radiotherapy, exercise of the affected arm, and the active participation in physical activity (P

OBJECTIVE We investigated the effects of mindfulness-based cognitive therapy on insomnia (MBCT-I) in breast cancer survivors. METHODS In total, 136 participants were allocated randomly to a MBCT-I group or a waitlist control (WLC) group. Indicators of insomnia and mindfulness were evaluated using the Insomnia Severity Index, actigraphy and the Five Facet Mindfulness Questionnaire. Data were collected at baseline (T1), post-intervention (T2), 3-month follow-up (T3) and 6-month follow-up (T4) time points. RESULTS Insomnia severity decreased significantly in the MBCT-I group, compared with the WLC group, at T2, T3 and T4 (all p

Purpose Breast cancer (BC) survivors have a lifelong risk of developing lymphedema . This study investigated the prevalence of BC-related arm lymphedema among Chinese BC survivors diagnosed in the last 10 years and examined the demographic and clinical variables as well as lifestyle factors associated with lymphedema status. Methods In this cross-sectional study, women with BC (N = 866) who had been diagnosed and followed up in the previous 10 years were recruited from the outpatient clinic of 4 general hospitals and one cancer association in China between August 2018 and October 2019. Lymphedema status was determined using the Norman telephone questionnaire as the patient-reported occurrence of hand/lower arm/upper arm swelling. Multiple logistic regression was used to identify risk factors for lymphedema. Results The median time from BC diagnosis was 4.0 years (interquartile range, 2.0–5.0 years). 81.4% of the patients had undergone mastectomy . The prevalence of arm lymphedema among BC survivors was 49.0%. Age ≥50 years, monthly income modified radical mastectomy , postsurgical wound infection, chemotherapy, and radiotherapy were associated with an increased risk of BC-related arm lymphedema, whereas exercise of the affected arm, engagement in active physical activity, and timely reporting of symptoms of infection to a physician decreased the risk (P Conclusions Arm lymphedema is a common complication for postoperative BC survivors within 10 years. It is essential to identify patients at risk of lymphedema based on demographic, clinical, and lifestyle factors and implement interventions targeting modifiable lifestyle behaviors-eg, active physical activity during the postoperative period .

High-speed true random number generator is a building block in the modern information security system. We propose and demonstrate an efficient high-speed true random number generator based on multiple parallel self-timed rings (STRs). To improve the security, we evaluate the randomness of the entropy source by min-entropy and exploit the information-theoretically provable Toeplitz-hashing extractor. To minimize the consumption of hardware resources of a field programmable gate array at a predetermined high throughput and maximize the throughput with the limited hardware resources, we systematically derive and investigate the dependence of the data throughput and the total consumed resources of the random number generator on the system parameters. On this basis, we make a joint optimization for the degree of parallelism of the STRs and the extraction efficiency of the extractor. A 10-Gbps true random number generator is implemented efficiently, so that the output random bits can pass all the National Institute of Standards and Technology (NIST) and Dieharder test suites.

ABC efflux proteins are a kind of transporters mediating diversified endogenous and exogenous efflux protein substrates across the plasma membrane by depending on the chemical energy released by ATP hydrolysis. As a vitally important functional membrane, it is widely found in various tissues and organs. The drug changes the expressions and/or functions of the transport proteins, which will affect the disposal process of substrate drugs corresponding to transporters

Efficient reconciliation is a crucial step in continuous variable quantum key distribution. The progressive-edge-growth (PEG) algorithm is an efficient method to construct relatively short block length low-density parity-check (LDPC) codes. The qua-sicyclic construction method can extend short block length codes and further eliminate the shortest cycle. In this paper, by combining the PEG algorithm and qua-si-cyclic construction method, we design long block length irregular LDPC codes with high error-correcting capacity. Based on these LDPC codes, we achieve high-efficiency Gaussian key reconciliation with slice recon-ciliation based on multilevel coding/multistage decoding with an efficiency of 93.7%.

Quantum key distribution (QKD) is the most mature application of quantum information technology. Information reconciliation is a crucial step in QKD and significantly affects the final secret key rates shared between two legitimate parties. We analyze and compare various construction methods of low-density parity-check (LDPC) codes and design high-performance irregular LDPC codes with a block length of 106. Starting from these good codes and exploiting the slice reconciliation technique based on multilevel coding and multistage decoding, we realize high-efficiency Gaussian key reconciliation with efficiency higher than 95% for signal-to-noise ratios above 1. Our demonstrated method can be readily applied in continuous variable QKD.

To study the C21 steroids of the stems of Marsdenia tenacissima (Roxb.) Wight et Arn, various chromatography methods were used for the isolation of the constituents and their structures were identified by spectral analysis. Eight C21 steroids were isolated from the CHCl3 extract, which were identified as 11alpha-O-tigloyl-17beta-tenacigenin B (1), 17beta-tenacigenin B (2), tenacigenoside A (3), 11alpha-O-2-methylbutyryl-12beta-O-acetyl tenacigenin B (4), tenacissoside H (5), marsdenoside A (6), tenacissoside G (7), and tenacissoside I (8). Among them, compound 1 is a new compound.