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Anastomotic leakage remains an issue after esophagectomy for patients with esophageal or esophagogastric junction cancer. Previous studies have indicated that the intraoperative application of fibrin sealant may reduce the incidence of postoperative anastomotic leakage. This retrospective study was aimed to evaluate the efficacy and safety of fibrin sealant in the prevention of anastomotic leakage in patients undergoing McKeown esophagectomy. We designed a single-center, retrospective study. Between January 2018 and December 2019, 227 patients with esophageal or esophagogastric junction cancer undergoing McKeown esophagectomy performed by our team were retrospectively identified, of whom 86 patients were included in the FS group and 141 patients were included in the control group. Intraoperatively, 2.5 ml of porcine fibrin sealant was applied circumferentially to the cervical anastomosis after the anastomosis was created in the FS group. The primary outcome was the incidence of cervical anastomotic leakage within the first three months after surgery. The differences in baseline clinical characteristics between the two groups were not significant except for a history of drinking. In the FS group, the postoperative cervical anastomotic leakage rate was lower (FS group: 4.7% [4 of 82] vs. control group: 19.9% [28 of 141], p < 0.01). Multivariate logistic regression showed that the intraoperative application of fibrin sealant was an independent protective factor for anastomotic leakage (OR 0.169, 95% CI 0.055-0.515, p = 0.002). The intraoperative application of fibrin sealant could possibly prevent cervical anastomotic leakage after McKeown esophagectomy with satisfactory safety. Further prospective clinical trials are warranted.

Food security has always been concerned by all countries. The grain production data of Anhui Province from 1990 to 2017 are selected, including: total grain production, sown area, etc. Low accuracy of food production forecasts has become a problem. We proposed a machine learning combination model GR-SVR based on Random Forest (RF), Gradient Boosting Decision Tree (GBDT) and Support Vector Regression Machine (SVR) to predict grain yield, using RF, GBDT, and SVR at the same time compare with GR-SVR. The results show that the GRSVR model has an accuracy rate higher than 96% in the prediction of grain output in Anhui Province, which is significantly better than GBDT, RF and SVR.

Objectives The purpose of this experiment is to analyze the changes of transcriptome in Pseudomonas aeruginosa under the action of sodium houttuyfonate (SH) to reveal the possible mechanism of SH inhibiting P. aeruginosa. We analyzed these data in order to compare the transcriptomic differences of P. aeruginosa in SH treatment and blank control groups. Data description In this project, RNA-seq of BGISEQ-500 platform was used to sequence the transcriptome of P. aeruginosa, and sequencing data of 8 samples of P. aeruginosa are generated as follows: SH treatment (SH1, SH2, SH3, SH4), negative control (Control 1, Control 2, Control 3, Control 4). Quality control is carried out on raw reads to determine whether the sequencing data is suitable for subsequent analysis. Totally 170.53 MB of transcriptome sequencing data is obtained. Then the filtered clean reads are aligned and compared to the reference genome to proceed second quality control. After completion, 5938 genes are assembled from sequencing data. Further quantitative analysis of genes and screening of differentially expressed genes based on gene expression level reveals that there are 2047 significantly differentially expressed genes under SH treatment, including 368 up-regulated genes and 1679 down-regulated genes.

Alcoholic liver disease (ALD) is caused by long-term consumption of alcohol and has become an important social and medical problem. Intestinal fungal flora (mycobiota) play an important role in ALD, so we used the mycobiota as an entry point to explore the mechanism of action of Paeonol against ALD. Here, we found that Paeonol is effective against ALD inflammatory lesions and relieves liver fat lesions. Furthermore, we found that after the treatment of Paeonol, the fungal dysbiosis is improved, and the fungal abundance is reduced, and the translocation of β-glucan to the liver and its mediated Dectin-1/IL-1β signaling pathway is blocked. Our study shows that paeonol ameliorated acute ALD-related inflammatory injury to the liver by alleviating intestinal fungal dysbiosis and inhibiting the mycobiota-mediated Dectin-1/IL-1β signaling pathway.

Background Deformed wing virus (DWV) is one of many viruses that infect honeybees and has been extensively studied because of its close association with honeybee colony collapse that is induced by Varroa destructor. However, virus genotypes, sequence characteristics, and genetic variations of DWV remain unknown in China. Methods Two DWV strains were isolated from Jinzhou and Qinhuangdao cities in China, and were named China1-2017 (accession number: MF770715) and China2-2018 (accession number: MH165180), respectively, and their complete genome sequences were analyzed. To investigate the phylogenetic relationships of the DWV isolates, a phylogenetic tree of the complete open reading frame (ORF), structural protein VP1, and non-structural protein 3C+RdRp of the DWV sequences was constructed using the MEGA 5.0 software program. Then, the similarity and recombinant events of the DWV isolated strains were analyzed using recombination detection program (RDP4) software and genetic algorithm for recombination detection (GARD). Results The complete genomic analysis showed that the genomes of the China1-2017 and China2-2018 DWV strains consisted of 10,141 base pairs (bp) and 10,105 bp, respectively, and contained a single, large ORF (China1-2017: 1,146–9,827 bp; China2-2018: 1,351–9,816 bp) that encoded 2,894 amino acids. The sequences were compared with 20 previously reported DWV sequences from different countries and with sequences of two closely related viruses, Kakugo virus (KV) and V. destructor virus-1. Multiple sequence comparisons revealed a nucleotide identity of 84.3–96.7%, and identity of 94.7–98.6% in amino acids between the two isolate strains and 20 reference strains. The two novel isolates showed 96.7% nucleotide identity and 98.1% amino acid identity. The phylogenetic analyses showed that the two isolates belonged to DWV Type A and were closely related to the KV-2001 strain from Japan. Based on the RDP4 and GARD analyses, the recombination of the China2-2018 strain was located at the 4,266–7,507 nt region, with Korea I-2012 as an infer unknown parent and China-2017 as a minor parent, which spanned the entire helicase ORF. To the best of our knowledge, this is the first study to the complete sequence of DWV isolated from Apis cerana and the possible DWV recombination events in China. Our findings are important for further research of the phylogenetic relationship of DWVs in China with DWV strains from other countries and also contribute to the understanding of virological properties of these complex DWV recombinants.

Frequency offset correction (FOC) is essential for a coherent optical orthogonal frequency-division multiplexing (CO-OFDM) system. In this paper, we proposed a robust and efficient FOC algorithm by designing training symbols in frequency domain. This algorithm has an advantage in overcoming imperfect frequency response induced by transmitter devices and physical channel implementations. To further improve the stability of the FOC algorithm against the optical signal-to-noise ratio degradation, a two-step iterative operation is introduced. The proposed algorithm has been utilized in a practical 100-km 16QAM-CO-OFDM transmission system to compensate the frequency offset dynamically. The efficiency and robustness of the algorithm have been validated by outstanding and stable experimental results.

A novel Brillouin optical time-domain analysis (BOTDA) system is demonstrated using intensity-modulated optical orthogonal frequency division multiplexing probe signal and direct detection (IM-DD-OOFDM) for stimulated Brillouin spectrum (SBS) measurement without frequency sweep operation. The SBS is reconstructed by channel estimation algorithm and Brillouin frequency shift (BFS) is located by curve fitting. The IM-DD-OOFDM BOTDA is demonstrated experimentally with 25m spatial resolution over 2 km standard single mode fiber.

Nanocrystalline C40-structured (Mo1 − xCrx)Si2 films were engineered onto Ti 6Al 4V substrates by a double glow discharge plasma technique. The electrochemical behavior of the newly developed films in a 3.5 wt.% NaCl solution was characterized by electrochemical techniques including open circuit potential, potentiodynamic polarization, and electrochemical impedance spectroscopy. To gain a deeper understanding of the role of Cr alloying in corrosion resistance, both cohesive energy and Mulliken population of the interatomic bonds in C40 (Mo1 − xCrx)Si2 were calculated based on the first-principles density-functional theory.

With fractional Fourier transform (FrFT) encoded training symbols, we propose and implement a joint timing synchronization and frequency offset estimation algorithm for coherent optical OFDM systems to achieve robust time-frequency synchronization against poor SNR.

A novel Brillouin optical time-domain analysis (BOTDA) system without frequency sweep operation is proposed using intensity-modulated direct detection optical orthogonal frequency division multiplexing (IM-DD-OOFDM) probe signal. The influence of peak to average power ratio (PAPR) of OFDM probe signal on the recovery of Brillouin gain spectrum (BGS) is analyzed in theory and experiment. The complex BGS is reconstructed by channel estimation algorithm and Brillouin frequency shift (BFS) is located by curve fitting of intensity spectrum. The IM-DD-OOFDM BOTDA is demonstrated experimentally with 25 m spatial resolution over 10 km standard single mode fibers within much less measurement time.

In this letter, we demonstrate that the interplay between Raman pump relative intensity noise and cross-phase modulation leads to a relative phase noise (RPN) that brings non-negligible performance degradation to coherent optical orthogonal frequency-division multiplexing (CO-OFDM) transmission systems with co-pumped Raman amplification. By theoretical analysis and numerical simulation, we proved that RPN brings more system impairment in terms of Q-factor penalty than the single carrier system, and relatively larger walk-off between pump and signal helps to suppress the RPN induced impairment. A higher-order modulated signal is less tolerant to RPN than a lower-order signal. With the same spectral efficiency, the quadrature-amplitude modulation format shows better tolerance to RPN than phase-shift keying. The reported findings will be useful for the design and optimization of Raman amplified CO-OFDM multi-carrier transmission systems. Published version

The intensity fluctuation of a Raman pump laser source will not only transfer to the signal's intensity through stimulated Raman scattering effect, which has been investigated comprehensively from both theoretical and experimental perspective, but also affect signal's phase through cross-phase modulation (XPM) effect. The phase noise is characterized by relative phase noise (RPN) parameter. Although the analytical model of RPN was proposed and the simulations were performed, no experimental verification has been carried on so far. In order to verify the statistical property of RPN, we conducted an experiment to measure the RPN transfer function using a continuous-wave signal and a modulated Raman pump laser diode. The measurement result for the co-pumping configuration has achieved good agreement with the theoretical calculation, validating the proposed theory. In addition to the measurement, we found clear Raman pump induced phase modulation in the experiment using a CO-OFDM signal, demonstrating that RPN will occur in a practical transmission system. With the measured RPN transfer function and the prior knowledge of Raman pump relative intensity noise, we can predict the RPN induced system performance degradation in a theoretical manner.

We proposed and demonstrated a cost-effective in-band optical signal to noise ratio (OSNR) monitoring technique based on coherent hybrid in 20Gb/s CO-OFDM system. Less than 0.5dB monitoring error is achieved with 400MHz balanced photodetector (PD).

50Km SSMF optical direct-detected OFDM transmission with Constant Amplitude Zero Auto Correlation Sequence (CAZAC) equalization is experimentally demonstrated with over 15dB power budget. 2.5dB enhancement in sensitivity has been achieved simultaneously with 3dB PAPR suppression.