Wavelength switchable flat-top all-fiber comb filter based on a double-loop Mach-Zehnder interferometer

Luo, Ai-Ping,Luo, Zhi-Chao,Xu, Wen-Cheng,Cui, Hu The Optical Society 2010 Optics express Vol.18 No.6

<P>A wavelength switchable all-fiber comb filter with flat-top spectral response based on a double-loop Mach-Zehnder (M-Z) interferometer is proposed and demonstrated. The proposed flat-top filter consists of a rotatable polarizer and a double-loop M-Z interferometer composed of two fiber couplers with a polarization controller (PC) in the first loop. In the theoretical analysis, when the second coupler of the M-Z interferometer is a non-3dB one, with proper settings of the polarization state of the input light and the PC, the wavelength switchable comb filter with flat-top passband can be obtained. Theoretical prediction was verified by experimental demonstration. The measured 1 dB bandwidth was 0.51 nm with a channel spacing of 0.98 nm, indicating that the flat-top passband of 1 dB bandwidth extends to about 50% of the comb spacing.</P>

Arachidonic Acid 15-Lipoxygenase: Effects of Its Expression, Metabolites, and Genetic and Epigenetic Variations on Airway Inflammation

Xu Xu,Li Jingyun,Zhang Yuan,Zhang Luo 대한천식알레르기학회 2021 Allergy, Asthma & Immunology Research Vol.13 No.5

Arachidonic acid 15-lipoxygenase (ALOX15) is an enzyme that can oxidize polyunsaturated fatty acids. ALOX15 is strongly expressed in airway epithelial cells, where it catalyzes the conversion of arachidonic acid to 15-hydroxyeicosatetraenoic acid (15-HETE) involved in various airway inflammatory diseases. Interleukin (IL)-4 and IL-13 induce ALOX15 expression by activating Jak2 and Tyk2 kinases as well as signal transducers and activators of transcription (STATs) 1/3/5/6. ALOX15 up-regulation and subsequent association with phosphatidylethanolamine-binding protein 1 (PEBP1) activate the mitogen-activated extracellular signal-regulated kinase (MEK)-extracellular signal-regulated kinase (ERK) pathway, thus inducing eosinophil-mediated airway inflammation. In addition, ALOX15 plays a significant role in promoting the migration of immune cells, such as immature dendritic cells, activated T cells, and mast cells, and airway remodeling, including goblet cell differentiation. Genome-wide association studies have revealed multiple ALOX15 variants and their significant correlation with the risk of developing airway diseases. The epigenetic modifications of the ALOX15 gene, such as DNA methylation and histone modifications, have been shown to closely relate with airway inflammation. This review summarizes the role of ALOX15 in different phenotypes of asthma, chronic obstructive pulmonary disease, chronic rhinosinusitis, aspirin-exacerbated respiratory disease, and nasal polyps, suggesting new treatment strategies for these airway inflammatory diseases with complex etiology and poor treatment response.

Effect of composite biological preservative containing Lactobacillus plantarum on postharvest litchi quality

Xu, Cong,Hu, Wen-feng,Luo, Shi,Luo, Hua-jian,Ma, Ke,Li, Yan-fang 한국식품과학회 2016 Food Science and Biotechnology Vol.25 No.6

Biological preservatives containing live microorganisms are environmentally friendly and non-toxic substances used to preserve the quality of fresh fruits. This study investigated whether a composite biological preservative containing live Lactobacillus plantarum (designated as DN003) could preserve the quality of postharvest litchi fruits at high temperature and in humid environment. Postharvest litchi fruits were briefly soaked in DN003, then dried and stored at $29-33^{\circ}C$ with 95-98% relative humidity; prochloraz treatment was included as positive control and non-treatment as negative control. In comparison with negative control group, litchi fruits in both DN003-treated and positive control groups better retained their appearance with lower polyphenol oxidase and peroxidase activities and showed higher concentrations of vitamin C, titratable acids, and total sugar content. These data demonstrated that the new composite biological preservative containing L. plantarum is promising to be used in the preservation of postharvest litchi fruit, particularly in high-temperature and humid environment.

Synthesis and Characterization of pH and Temperature Sensitive Hydrogel Based on Poly(N-isopropylacrylamide), Poly(ε-caprolactone), Methylacrylic Acid, and Methoxyl Poly(ethylene glycol)

Xu Xu,Jia Song,Ke Wang,YingChun Gu,Feng Luo,XiaoHai Tang,Ping Xie,ZhiYong Qian 한국고분자학회 2013 Macromolecular Research Vol.21 No.8

In this paper, a novel biodegradable and pH/thermo-sensitive hydrogel based on poly(ε-caprolactone),methoxyl poly(ethylene glycol), methylacrylic acid and N-isopropylacrylamide was prepared by UV-initiated free radical polymerization. The hydrogels were characterized by Fourier transforms infrared ray. The thermal responsibility was investigated with the help of differential scanning calorimetry. Swelling behavior in aqueous medium with different pH value was studied in detail. When the pH value of the aqueous medium was increased from 1.2 to 7.2,the swelling ratio of the hydrogels increased accordingly. The morphology was observed by scanning electron microscopy, and the hydrolytic degradation behavior in different aqueous media (pH 1.2 and pH 7.2) was also investigated in detail. The prepared biodegradable pH/thermo-sensitive hydrogel based on poly(ε-caprolactone), methoxyl poly(ethylene glycol), methylacrylic acid and N-isopropylacrylamide hold great promise in the development of a smart drug delivery system.

Research on the Optimization of the Performance of CTL Loop Discriminator

Xu Ying,Yuan Hong,Luo Ruidan,Xu Duo 보안공학연구지원센터 2015 International Journal of Future Generation Communi Vol.8 No.5

Chip Tracking Loop (CTL) is the key to ensure the accuracy of regenerative pseudo-noise ranging in the deep space measurement and control communication system. However, due to the impact of the code imbalance, clock attenuation rate and noise, the loop locking time of CTL is prolonged and the ranging accuracy is degraded. In this paper, we proposed the discriminator optimization algorithm to address this problem. This algorithm is based on the loop discrimination performance of clock code and composite code, and the impact of the noise on the discrimination performance. In order to improve the tracking accuracy and shorten the loop locking time, this algorithm corrected the curve of discriminator’s gain by compensating discriminator’s gain. Both the theory analysis and simulation results illustrate that the algorithm can correct the discriminator’s gain curve, reduce the loop locking time and ensure the significant tracking accuracy in low SNR.

Prediction of essential genes in prokaryote based on artificial neural network

Luo Xu,Zhirui Guo,Xiao Liu 한국유전학회 2020 Genes & Genomics Vol.42 No.1

Background Rapid identification of new essential genes is necessary to understand biological mechanisms and identify potential targets for antimicrobial drugs. Many computational methods have been proposed. Objectives To construct an essential genes classifier which satisfies more different organisms, and to study the redundancy of features used in the prediction of essential genes. Methods We designed a 57-12-1 artificial neural network model to predict the essential genes of 31 prokaryotic genomes. Four methods including self-predictions of each organism, the leave-one-genome-out method, predicting all by one organism, and self-predictions of all organisms were applied to assess the predictive performance. Additionally, the 57 features used in the artificial neural network model were analyzed by weighted principal component analysis to screen the key features strongly related to the essentiality of genes. Results Our results compared with previous researches indicate that our models had better generalizability. Furthermore, this method reduced the features to 29 while maintaining stable prediction performance overall, suggesting that some features are redundant for gene essentiality, and the screened features contained more important biological information for gene essentiality. Conclusion This study showed the effectiveness and generalizability of our artificial neural network model. In addition, the screened features could be used as key features in computational analysis and biological experiments.

LncRNA TMPO-AS1 promotes esophageal squamous cell carcinoma progression by forming biomolecular condensates with FUS and p300 to regulate TMPO transcription

Luo Xiao-Jing,He Ming-Ming,Liu Jia,Zheng Jia-Bo,Wu Qi-Nian,Chen Yan-Xing,Meng Qi,Luo Kong-Jia,Chen Dong-Liang,Xu Rui-Hua,Zeng Zhao-Lei,Liu Ze-Xian,Luo Hui-Yan 생화학분자생물학회 2022 Experimental and molecular medicine Vol.54 No.-

Esophageal squamous cell carcinoma (ESCC) is one of the most life- and health-threatening malignant diseases worldwide, especially in China. Long noncoding RNAs (lncRNAs) have emerged as important regulators of tumorigenesis and tumor progression. However, the roles and mechanisms of lncRNAs in ESCC require further exploration. Here, in combination with a small interfering RNA (siRNA) library targeting specific lncRNAs, we performed MTS and Transwell assays to screen functional lncRNAs that were overexpressed in ESCC. TMPO-AS1 expression was significantly upregulated in ESCC tumor samples, with higher TMPOAS1 expression positively correlated with shorter overall survival times. In vitro and in vivo functional experiments revealed that TMPO-AS1 promotes the proliferation and metastasis of ESCC cells. Mechanistically, TMPO-AS1 bound to fused in sarcoma (FUS) and recruited p300 to the TMPO promoter, forming biomolecular condensates in situ to activate TMPO transcription in cis by increasing the acetylation of histone H3 lysine 27 (H3K27ac). Targeting TMPO-AS1 led to impaired ESCC tumor growth in a patient-derived xenograft (PDX) model. We found that TMPO-AS1 is required for cell proliferation and metastasis in ESCC by promoting the expression of TMPO, and both TMPO-AS1 and TMPO might be potential biomarkers and therapeutic targets in ESCC.

Elastic Foundation Beam Solution of Tensile Flexible Retaining Wall

Xu Jianqiang,Xu Jiangbo,Yang Xiaohua,Yan Zhaobai,Li Haiping,Wang Huoming,Tan Ling,Fei Dongyang,Li Jianguo,Luo Yongzhen 한국강구조학회 2022 International Journal of Steel Structures Vol.22 No.2

The application of fl exible retaining walls in foundation pit engineering is gradually increasing. At present, many practical engineering problems need to be solved. This article takes a corrugated steel retaining wall with tensile reinforcement, for example, assuming that it is an elastic foundation beam model. A typical vertical thin layer unit is taken on the retaining wall for analysis. It uses the waveform integration method to calculate the moment of inertia, deriving the diff erential equation of fl exural deformation of corrugated steel retaining wall and establishing the theoretical formula for deformation of corrugated steel retaining wall under fi lling pressure behind the wall. Finally, a FLAC3D model was established to simulate the deformation of corrugated steel retaining walls in practical engineering, and the fi nal numerical simulation results were consistent with the theoretical formula. Thus, providing a theoretical basis for the deformation of such fl exible retaining structures.

Genomics and expression analysis of DHHC-cysteine-rich domain S-acyl transferase protein family in apple

Ruirui Xu,Yuemin Zhang,Meihong Sun,Xiuyan Zhao,Nan Xu,Xiaocui Luo 한국유전학회 2016 Genes & Genomics Vol.38 No.8

S-acylation is one of a group of lipid modifications that occurs on eukaryotic proteins, mediated by DHHC-CRD-containing proteins, which plays an important role in regulating the membrane association, trafficking and function of target proteins. Although genome-wide identification of PAT family has been carried out in yeast, mice, humans and Arabidopsis, little is known about apple PAT genes. In this study, a total of 33 putative apple PAT proteins, containing DHHC-CRD by domain analysis, have been identified, and were classified into three groups according to the phylogenetic analysis of PAT proteins in apple and Arabidopsis. More complex TMDs in the most MdPATs revealed the PM location of the gene family. Gene structure, gene chromosomal location and paralogs analysis of MdPAT genes within the apple genome demonstrated that tandem and segmental duplications, as well as whole genome duplications, have likely contributed to the expansion and evolution of the PAT gene family in apple. According to the microarray and expressed sequence tag (ESTs) analysis, the different expression patterns indicate that they may play different roles during fruit development and rootstock-scion interactions process. Moreover, PATs were performed expression profile analyses in different tissues, indicating that the PATs are involved in various aspects of physiological and developmental processes of apple. To our knowledge, this is the first report of a genome-wide analysis of the apple PAT gene family, and this genomic analysis of apple DHHCCRD PAT genes provides the first step towards a functional study of this gene family in apple.

Effect of composite biological preservative containing Lactobacillus plantarum on postharvest litchi quality

Cong Xu,Wen-feng Hu,Shi Luo,Hua-jian Luo,Ke Ma,Yan-fang Li 한국식품과학회 2016 Food Science and Biotechnology Vol.25 No.6

Biological preservatives containing live microorganisms are environmentally friendly and non-toxic substances used to preserve the quality of fresh fruits. This study investigated whether a composite biological preservative containing live Lactobacillus plantarum (designated as DN003) could preserve the quality of postharvest litchi fruits at high temperature and in humid environment. Postharvest litchi fruits were briefly soaked in DN003, then dried and stored at 29–33oC with 95–98% relative humidity; prochloraz treatment was included as positive control and non-treatment as negative control. In comparison with negative control group, litchi fruits in both DN003-treated and positive control groups better retained their appearance with lower polyphenol oxidase and peroxidase activities and showed higher concentrations of vitamin C, titratable acids, and total sugar content. These data demonstrated that the new composite biological preservative containing L. plantarum is promising to be used in the preservation of postharvest litchi fruit, particularly in hightemperature and humid environment.