Directional production of even carbon volatile fatty acids from peanut meal: effects of initial pH and hydraulic residence time

Yujia Chen,Qian Fang,Lu Zhang,Kequan Zhang,Tong Wei,Qiqi Ping 대한환경공학회 2022 Environmental Engineering Research Vol.27 No.4

In this study, peanut meal was used as the substrate for the continuous production of even carbon volatile fatty acids (ECFA) through anaerobic fermentation. First, a continuous stirred reactor (CSTR) was started by adjusting the initial pH to acclimate the related bacteria, and then the hydraulic residence time (HRT) was optimized. The effects of different initial pH and HRT on the potential of ECFA production by peanut meal fermentation, the transformation and utilization of main organic compounds, and the composition and replacement of microbial community structure behind it were investigated. The results showed that ECFA was the dominant factor in the acid production of peanut meal fermentation, and alkaline pH and HRT = 6 d were the more favorable operating conditions for the hydrolysis and acidification of peanut meal. The average concentration of total volatile fatty acids (TVFAs) obtained was 15,249.50 mg/L, and the content of ECFA varied from 88.51% to 96.27%, with an average ratio of 92.55%. This operation condition drove the formation of microbial community structure, mainly including Prepotella, Tepididimicrobium, Anaerosalibacter, and Igatzschineria, which were favorable for ECFA production, reflecting the potential of using peanut meal for targeted production of ECFA.

Colonic Transit Disorder Mediated by Downregulation of Interstitial Cells of Cajal/Anoctamin-1 in Dextran Sodium Sulfate-induced Colitis Mice

Chen Lu,Hongli Lu,Xu Huang,Shaohua Liu,Jingyu Zang,Yujia Li,Jie Chen,Wenxie Xu 대한소화기 기능성질환∙운동학회 2019 Journal of Neurogastroenterology and Motility (JNM Vol.25 No.2

Background/Aims Interstitial cells of Cajal (ICC) and their special calcium-activated chloride channel, anoctamin-1 (ANO1) play pivotal roles in regulating colonic transit. This study is designed to investigate the role of ICC and the ANO1 channel in colonic transit disorder in dextran sodium sulfate (DSS)-treated colitis mice. Methods Colonic transit experiment, colonic migrating motor complexes (CMMCs), smooth muscle spontaneous contractile experiments, intracellular electrical recordings, western blotting analysis, and quantitative polymerase chain reaction were applied in this study. Results The mRNA and protein expressions of c-KIT and ANO1 channels were significantly decreased in the colons of DSS-colitis mice. The colonic artificial fecal-pellet transit experiment in vitro was significantly delayed in DSS-colitis mice. The CMMCs and smooth muscle spontaneous contractions were significantly decreased by 5-nitro-2-(3-phenylpropylamino)benzoic acid (NPPB), an ANO1 channel blocker, and NG-Nitro-L-arginine methyl ester hydrochloride (L-NAME), an inhibitor of nitric oxide synthase activity, in DSS-colitis mice compared with that of control mice. Intracellular electrical recordings showed that the amplitude of NPPB-induced hyperpolarization was more positive in DSS-colitis mice. The electric field stimulation-elicited nitric-dependent slow inhibitory junctional potentials were also more positive in DSS-colitis mice than those of control mice. Conclusion The results suggest that colonic transit disorder is mediated via downregulation of the nitric oxide/ICC/ANO1 signalling pathway in DSS-colitis mice.

Overexpression of miR-155-5p Inhibits the Proliferation and Migration of IL-13-Induced Human Bronchial Smooth Muscle Cells by Suppressing TGF-β-Activated Kinase 1/MAP3K7-Binding Protein 2

Yujia Shi,Xingli Fu,Qi Cao,Zhengdao Mao,Yi Chen,Yun Sun,Zhiguang Liu,Qian Zhang 대한천식알레르기학회 2018 Allergy, Asthma & Immunology Research Vol.10 No.3

Purpose: Molecular mechanisms leading to asthma is still ill-defined. Though the function of microRNAs (miRNAs) in asthma was previously reported, the involvement of miR-155 in important features of this disease remains unknown. The present study was designed to uncover the probable involvement of miR-155-5p in the proliferation and migration of IL-13-induced human bronchial smooth muscle cells (BSMCs) and the intrinsic regulatory mechanism. Methods: The effects of different concentrations of IL-13 on the proliferation and migration of BSMCs as well as the expression of miR-155-5p and its predicted target transforming growth factor (TGF)-β-activated kinase 1/MAP3K7-binding protein 2 (TAB2) were investigated. The effects of miR-155-5p on the proliferation and migration of interleukin (IL)-13-induced BSMCs was determined in vitro using BSMCs transfected with miR-155 mimic/inhibitor and induced by a high concentration of IL-13. The quantitative real-time polymerase chain reaction (qRT-PCR) was employed for determining the expression of miR-155-5p and TAB2. Western blotting was applied to analyze the expression of TAB2 at the protein level. Cell proliferation and migration were assessed using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) and Transwell assays, respectively. Results: The proliferation and migration of BSMCs were dose-dependently increased with IL-13 treatment. Contrariwise, IL-13 dose-dependently inhibited the expression of miR-155-5p in BSMCs. Mechanistic studies showed that inhibition of miR-155-5p further promoted the stimulatory effects of IL-13, whereas overexpression of miR-155 significantly inhibited these effects. In silico studies and luciferase reporter assays indicated that TAB2 was a negatively regulated miR-155-5p target. Conclusions: These results suggested that miR-155-5p-inhibit the IL-13-induced proliferation and migration of BSMCs by targeting TAB2 and that the IL-13/miR-155/TAB2 pathway could serve as a therapeutic target for pulmonary diseases, especially asthma.

Maximizing Information Transmission for Energy Harvesting Sensor Networks by an Uneven Clustering Protocol and Energy Management

( Yujia Ge ),( Yurong Nan ),( Yi Chen ) 한국인터넷정보학회 2020 KSII Transactions on Internet and Information Syst Vol.14 No.4

For an energy harvesting sensor network, when the network lifetime is not the only primary goal, maximizing the network performance under environmental energy harvesting becomes a more critical issue. However, clustering protocols that aim at providing maximum information throughput have not been thoroughly explored in Energy Harvesting Wireless Sensor Networks (EH-WSNs). In this paper, clustering protocols are studied for maximizing the data transmission in the whole network. Based on a long short-term memory (LSTM) energy predictor and node energy consumption and supplement models, an uneven clustering protocol is proposed where the cluster head selection and cluster size control are thoroughly designed for this purpose. Simulations and results verify that the proposed scheme can outperform some classic schemes by having more data packets received by the cluster heads (CHs) and the base station (BS) under these energy constraints. The outcomes of this paper also provide some insights for choosing clustering routing protocols in EH-WSNs, by exploiting the factors such as uneven clustering size, number of clusters, multiple CHs, multihop routing strategy, and energy supplementing period.

Observer design with Gershgorin’s disc

Chen Si,Yujia Zhai 한국융합학회 2013 한국융합학회논문지 Vol.4 No.4

Overview of Active Disturbance Rejection Control for Permanent Magnet Synchronous Motors

Zhang Xinhua,Chen Yujia,Sun Xiaodong 대한전기학회 2024 Journal of Electrical Engineering & Technology Vol.19 No.3

The ubiquitous implementation of permanent magnet synchronous motors (PMSMs) in contemporary alternating current propulsion systems is widely acknowledged. As a superior control method that does not rely on a precise system mathematical model and has superior robustness, Active Disturbance Rejection Control (ADRC) is widely used to improve the overall control performance and efciency of the PMSM drive system. Starting from three parts of ADRC, this paper comprehensively expounds on the advantages of the ADRC control strategy and its shortcomings in the application at present. The problems of too many parameters, not easily controlling the nonlinear part, and difculty in adjusting the parameters are summarized. Then the performance improvement schemes of ADRC such as structure optimization, parameter tuning, nonlinear part optimization, and simplifed parameters are summarized. Finally, the future development trend of the control algorithm is forecasted.

Numerical investigation on pressure responsiveness properties of the skirt-cushion system of an air cushion vehicle

Xu, Shengjie,Tang, Yujia,Chen, Kejie,Zhang, Zongke,Ma, Tao,Tang, Wenyong The Society of Naval Architects of Korea 2020 International Journal of Naval Architecture and Oc Vol.12 No.1

The pressure responsiveness property of a skirt-cushion system, which is closely related to the overall performance of Air Cushion Vehicles (ACVs), has always been the difficulty and challenging problem involving cushion aerodynamics and flexible skirt dynamics. Based on a widely used bag and finger skirt-cushion system, the pressure responsiveness properties are investigated numerically. The physical process and mechanism are analyzed and a numerical method for evaluating the pressure responsiveness property is proposed. A cushion-skirt information communication platform is also presented for interchanging the force and the skirt configuration between cushion aerodynamics and flexible skirt dynamics. The pressure responsiveness of a typical skirt-cushion system is calculated and the results demonstrate that the pressure responsiveness property helps alleviate the influence of the cushion height changing on the overall performance of ACVs. Finally, the influences of skirt geometrical and cushion aerodynamic parameters on the pressure responsiveness properties are discussed systematically, giving insight into the design of skirt-cushion systems.

Numerical investigation on pressure responsiveness properties of the skirt-cushion system of an air cushion vehicle

Xu, Shengjie,Tang, Yujia,Chen, Kejie,Zhang, Zongke,Ma, Tao,Tang, Wenyong The Society of Naval Architects of Korea 2020 International Journal of Naval Architecture and Oc Vol.12 No.-

The pressure responsiveness property of a skirt-cushion system, which is closely related to the overall performance of Air Cushion Vehicles (ACVs), has always been the difficulty and challenging problem involving cushion aerodynamics and flexible skirt dynamics. Based on a widely used bag and finger skirt-cushion system, the pressure responsiveness properties are investigated numerically. The physical process and mechanism are analyzed and a numerical method for evaluating the pressure responsiveness property is proposed. A cushion-skirt information communication platform is also presented for interchanging the force and the skirt configuration between cushion aerodynamics and flexible skirt dynamics. The pressure responsiveness of a typical skirt-cushion system is calculated and the results demonstrate that the pressure responsiveness property helps alleviate the influence of the cushion height changing on the overall performance of ACVs. Finally, the influences of skirt geometrical and cushion aerodynamic parameters on the pressure responsiveness properties are discussed systematically, giving insight into the design of skirt-cushion systems.

The synthesis of polyhydroxyalkanoates from low carbon wastewater under anaerobic-microaerobic process: effects of pH and nitrogen and phosphorus limitation

Kequan Zhang,Qian Fang,Yihan Xie,Yujia Chen,Tong Wei,Yanyu Xiao 대한환경공학회 2022 Environmental Engineering Research Vol.27 No.6

Polyhydroxyalkanoate (PHA) is a new type of bio-polyester which is expected to replace traditional petroleum-based plastics. The experiment was carried out based on anaerobic-microaerobic process. Firstly, the PHA accumulation capacity of activated sludge under different pH conditions was discussed, and then the batch test of nitrogen and phosphorus limitation was carried out under the condition of optimal pH. Moreover, the content of PHA monomer under nutrient restriction was also studied. The experimental results showed that when pH was not controlled (7.5~8.5), C:N and C:P weight ratio was equal to 150, the maximum content of PHA accounted for 50.39% and 36.07% of the dry cell weight, respectively. Besides, it was found that increasing the C:N weight ratio was beneficial to increasing the proportion of polyhydroxyvalerate (PHV) monomer in PHA.

A novel calculation model for the permeability coefficient of soils conditioned with foam and bentonite slurry

Fanlin Ling,Shuying Wang,Xiangcou Zheng,Jiazheng Zhong,Yujia Chen 대한토목학회 2024 KSCE Journal of Civil Engineering Vol.28 No.5

Both foam and bentonite slurry are commonly employed in soil conditioning to prevent water spewing during earth pressure balance (EPB) shield tunnelling. A novel calculation model to estimate the permeability coefficient of soils conditioned with foam and bentonite slurry is developed. In this model, bentonite particles are assumed to adhere to the foam film in a monolayer of bridging particles, and the permeation channels within the conditioned soil are updated using the Kozeny-Carman equation. A series of permeability tests on conditioned soil, varying conditioning parameters and water heads, validate the accuracy of the model. The measured results that the value of permeability coefficient can be well captured by the calculation results, which indicates that the model can accurately predict the permeability of soil conditioning by foam and bentonite slurry. While there is a slight reduction in accuracy for conditioning states with high foam and bentonite slurry injection ratios, the model remains conservative for tunnelling engineering safety due to calculated values consistently exceeding measured ones. Furthermore, the model performs well in cases of foam-conditioned soil from previous studies. Additionally, the model underscores the significant influence of bentonite slurry on the permeability coefficient by altering soil grain gradation.