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  1. Article ; Online: Frequency Difference Thermally and Electrically Tunable Dual-Frequency Nd:YAG/LiTaO 3 Microchip Laser

    Kun Gui / Zilong Zhang / Yuxiao Xing / Haiyang Zhang / Changming Zhao

    Applied Sciences, Vol 9, Iss 10, p

    2019  Volume 1969

    Abstract: This study presents a dual-frequency microchip laser with a thermo-optically and electro-optically tuned frequency difference. The dual-frequency microchip cavity is formed by bonding a Lithium tantalite (LiTaO 3 , LTO) crystal chip and a neodymium-doped ...

    Abstract This study presents a dual-frequency microchip laser with a thermo-optically and electro-optically tuned frequency difference. The dual-frequency microchip cavity is formed by bonding a Lithium tantalite (LiTaO 3 , LTO) crystal chip and a neodymium-doped yttrium aluminum garnet (Nd:YAG) crystal chip. A single longitudinal mode is generated by the Nd:YAG crystal and split into two frequencies with perpendicular polarizations due to birefringent effect in the LTO chip. Furthermore, continuous beat frequency tuning at different scales is realized by adjusting the temperature and voltage applied to the LTO crystal. A maximum beat frequency of up to 27 GHz is obtained, and the frequency difference lock-in phenomenon is observed below the frequency difference of 405 MHz.
    Keywords microwave photonics ; tunable dual frequency ; microchip laser ; electro-optic effect ; thermo-optic effect ; Technology ; T ; Engineering (General). Civil engineering (General) ; TA1-2040 ; Biology (General) ; QH301-705.5 ; Physics ; QC1-999 ; Chemistry ; QD1-999
    Subject code 535
    Language English
    Publishing date 2019-05-01T00:00:00Z
    Publisher MDPI AG
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  2. Article ; Online: Total flavonoids of Astragalus Ameliorated Bile Acid Metabolism Dysfunction in Diabetes Mellitus

    Zhe Wang / Xu-Ling Li / Kin-Fong Hong / Ting-Ting Zhao / Rui-Xue Dong / Wei-Ming Wang / Yun-Tong Li / Gui-Lin Zhang / Jing Lin / Ding-Kun Gui / You-Hua Xu

    Evidence-Based Complementary and Alternative Medicine, Vol

    2021  Volume 2021

    Abstract: Astragalus Radix is one of the common traditional Chinese medicines used to treat diabetes. However, the underlying mechanism is not fully understood. Flavones are a class of active components that have been reported to exert various activities. Existing ...

    Abstract Astragalus Radix is one of the common traditional Chinese medicines used to treat diabetes. However, the underlying mechanism is not fully understood. Flavones are a class of active components that have been reported to exert various activities. Existing evidence suggests that flavones from Astragalus Radix may be pivotal in modulating progression of diabetes. In this study, total flavones from Astragalus Radix (TFA) were studied to observe its effects on metabolism of bile acids both in vivo and in vitro. C57BL/6J mice were treated with STZ and high-fat feeding to construct diabetic model, and HepG2 cell line was applied to investigate the influence of TFA on liver cells. We found a serious disturbance of bile acids and lipid metabolism in diabetic mice, and oral administration or cell incubation with TFA significantly reduced the production of total cholesterol (TCHO), total triglyceride, glutamic oxalacetic transaminase (AST), glutamic-pyruvic transaminase (ALT), and low-density lipoprotein (LDL-C), while it increased the level of high-density lipoprotein (HDL-C). The expression of glucose transporter 2 (GLUT2) and cholesterol 7α-hydroxylase (CYP7A1) was significantly upregulated on TFA treatment, and FXR and TGR5 play pivotal role in modulating bile acid and lipid metabolism. This study supplied a novel understanding towards the mechanism of Astragalus Radix on controlling diabetes.
    Keywords Other systems of medicine ; RZ201-999
    Subject code 571
    Language English
    Publishing date 2021-01-01T00:00:00Z
    Publisher Hindawi Limited
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  3. Article: Numerical study on wave attenuation inside and around a square array of biofouled net cages

    Bi, Chun-Wei / Fu-Kun Gui / Guo-Hai Dong / Tiao-Jian Xu / Yun-Peng Zhao

    Aquacultural engineering. 2017 Aug., v. 78

    2017  

    Abstract: In this study, waves propagating through a square array of 16 net cages with different levels of biofouling are numerically studied using a three-dimensional computational fluid dynamics (CFD) model. A porous-media fluid model is adopted to simulate both ...

    Abstract In this study, waves propagating through a square array of 16 net cages with different levels of biofouling are numerically studied using a three-dimensional computational fluid dynamics (CFD) model. A porous-media fluid model is adopted to simulate both clean and biofouled netting of a cage array in waves. A numerical wave tank is built, and the oscillating-boundary method is adopted to generate waves. The flow motion is solved by the Navier-Stokes equations, and the free water surface is captured using the volume of fluid (VOF) method. The numerical model is validated by comparing the numerical data with corresponding experimental measurements of a net-cage model with clean netting. To analyze wave attenuation, a numerical analysis of wave elevation both inside and around the cage arrays is presented, which considers the effect of biofouling. Based on the results of the present study, the effect of biofouling on wave elevation is noticeable; the damping effect of the cage array increases with increasing level of biofouling. Furthermore, the incident angle of waves has a noticeable effect on the wave field inside and around the cage array.
    Keywords angle of incidence ; biofouling ; cages ; equations ; fluid mechanics ; mathematical models ; model validation ; netting ; porous media
    Language English
    Dates of publication 2017-08
    Size p. 180-189.
    Publishing place Elsevier B.V.
    Document type Article
    ZDB-ID 782663-1
    ISSN 0144-8609
    ISSN 0144-8609
    DOI 10.1016/j.aquaeng.2017.07.006
    Database NAL-Catalogue (AGRICOLA)

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  4. Article: A numerical analysis on the hydrodynamic characteristics of net cages using coupled fluid–structure interaction model

    Bi, Chun-Wei / Fu-Kun Gui / Guo-Hai Dong / Yan-Na Zheng / Yun-Peng Zhao

    Aquacultural engineering. 2014 Mar., v. 59

    2014  

    Abstract: A numerical approach is proposed to simulate the hydrodynamic characteristics of a net cage in a steady current. The numerical approach is based on the joint use of the porous-media fluid model and the lumped-mass mechanical model. The deformation of a ... ...

    Abstract A numerical approach is proposed to simulate the hydrodynamic characteristics of a net cage in a steady current. The numerical approach is based on the joint use of the porous-media fluid model and the lumped-mass mechanical model. The deformation of a net cage can be calculated using the lumped-mass mechanical model and the flow field around a fishing net can be simulated using the porous-media fluid model. Using an appropriate iterative scheme, the coupled fluid–structure interaction between the flow and net cage can be solved, and the steady flow field inside and around a net cage can be obtained. Using the proposed numerical approach, numerical simulations of flow through a single net cage in different currents, single net cage with different weight modes and multiple net cages are investigated. Validation of the numerical model is conducted by comparing the numerical results with the corresponding physical model measurements. The comparisons demonstrate that both the configuration of the net chamber and the flow-velocity results are in accordance with those of the corresponding physical model tests. It was determined that more accurate results can be obtained by considering the coupled fluid–structure interaction between the flow and the net cage.
    Keywords cages ; deformation ; fish nets ; hydrodynamics ; mathematical models ; porous media ; steady flow
    Language English
    Dates of publication 2014-03
    Size p. 1-12.
    Publishing place Elsevier B.V.
    Document type Article
    ZDB-ID 782663-1
    ISSN 0144-8609
    ISSN 0144-8609
    DOI 10.1016/j.aquaeng.2014.01.002
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  5. Article: Experimental investigation of the reduction in flow velocity downstream from a fishing net

    Bi, Chun-Wei / Fu-Kun Gui / Guo-Hai Dong / Tiao-Jian Xu / Yun-Peng Zhao

    Aquacultural engineering. 2013 Nov., v. 57

    2013  

    Abstract: A series of laboratory experiments was conducted to investigate the reduction in flow velocity downstream from a fishing net in a current. The flow-velocity distribution downstream from the plane net(s) was obtained using both the particle image ... ...

    Abstract A series of laboratory experiments was conducted to investigate the reduction in flow velocity downstream from a fishing net in a current. The flow-velocity distribution downstream from the plane net(s) was obtained using both the particle image velocimetry (PIV) technique and the acoustic Doppler velocimeter (ADV). The reduction in flow velocity was investigated with different net solidities, plane-net inclination angles, spacing distances between two plane nets and plane net numbers. The experimental data show that there was an obvious reduction in flow velocity downstream from the plane net and that the reduction increased with increasing net solidity. The reduction in flow velocity tended to increase with increasing inclination angle between the plane net and the vertical direction. For two plane nets with different spacing distances, the average reduction factor was 0.90 between the two nets and 0.83 downstream from the two nets. As the net number increased from 1 to 4, the minimum reduction factor downstream from the plane nets decreased from 0.90 to 0.68. The study will contribute to understanding of the flow characteristics around a net cage.
    Keywords acoustics ; cages ; fish nets ; laboratory experimentation ; spatial distribution
    Language English
    Dates of publication 2013-11
    Size p. 71-81.
    Publishing place Elsevier B.V.
    Document type Article
    ZDB-ID 782663-1
    ISSN 0144-8609
    ISSN 0144-8609
    DOI 10.1016/j.aquaeng.2013.08.002
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  6. Article: Numerical simulation of the flow field inside and around gravity cages

    Zhao, Yun-Peng / Chun-Wei Bi / Fu-Kun Gui / Guo-Hai Dong / Tiao-Jian Xu / Yong Cui

    Aquacultural engineering. 2013 Jan., v. 52

    2013  

    Abstract: A three-dimensional (3D) numerical model is established to simulate the flow field inside and around the gravity cages in a current. The realizable k–ɛ turbulence model was chosen to describe the flow, and the governing equations are solved by using the ... ...

    Abstract A three-dimensional (3D) numerical model is established to simulate the flow field inside and around the gravity cages in a current. The realizable k–ɛ turbulence model was chosen to describe the flow, and the governing equations are solved by using the finite volume method. In the numerical model the cylindrical cage is divided into 16 plane nets around the circumference and a bottom net, and the net is modeled using the porous media model. The unknown porous coefficients are determined from the hydrodynamic force on the net under different flow velocities and attack angles using the least squares method. In order to validate the numerical model, the numerical results of the plane nets were compared with the data obtained from two physical model tests. The comparisons show that the numerical results are in good agreement with the experimental data. Using the present model, this paper presents the flow field inside and around the gravity cages with different spacing distances and cage numbers. This study provides information about the flow field inside and around the fishing net cages.
    Keywords cages ; equations ; fish cages ; gravity ; least squares ; mathematical models ; physical models ; porous media ; simulation models ; turbulent flow
    Language English
    Dates of publication 2013-01
    Size p. 1-13.
    Publishing place Elsevier B.V.
    Document type Article
    ZDB-ID 782663-1
    ISSN 0144-8609
    ISSN 0144-8609
    DOI 10.1016/j.aquaeng.2012.06.001
    Database NAL-Catalogue (AGRICOLA)

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  7. Article: Eradication of human immunodeficiency virus type 1-infected cells by a combination of antimetabolic cytotoxic chemotherapy and antiviral chemotherapy in vitro: a pilot study.

    Yang, Quan-en / Li, Kun-gui / Mikovits, Judy A

    The Journal of infectious diseases

    2002  Volume 186, Issue 5, Page(s) 706–709

    Abstract: Although highly active antiretroviral therapy against human immunodeficiency virus (HIV) type 1 reduces the mortality of persons with acquired immunodeficiency syndrome, it does not eliminate HIV reservoirs. In this study, which used a 6-thioguanine (6- ... ...

    Abstract Although highly active antiretroviral therapy against human immunodeficiency virus (HIV) type 1 reduces the mortality of persons with acquired immunodeficiency syndrome, it does not eliminate HIV reservoirs. In this study, which used a 6-thioguanine (6-TG) resistant clone (4C6) of the MT-2 cell line as a model, the combination of 6-TG with both reverse-transcriptase (RT) inhibitor and protease inhibitor or 6-TG with a protease inhibitor alone completely eradicated HIV-1-carrying cells from the culture and protected uninfected 4C6 cells from HIV-1 infection. The combination of 6-TG and a RT inhibitor, azidothymidine, provided partial protection. Protection was extended to human peripheral blood mononuclear cells. These results suggest that adding a cytotoxic drug in combination antiviral chemotherapy may reduce the establishment of virus reservoirs and prevent virus spread. The clinical value of this and similar strategies should be further evaluated in HIV-infected patients.
    MeSH term(s) Cells, Cultured ; Drug Therapy, Combination ; HIV Core Protein p24/biosynthesis ; HIV Infections/drug therapy ; HIV Protease Inhibitors/pharmacology ; HIV-1/drug effects ; Humans ; Pilot Projects ; Reverse Transcriptase Inhibitors/pharmacology ; Thioguanine/pharmacology
    Chemical Substances HIV Core Protein p24 ; HIV Protease Inhibitors ; Reverse Transcriptase Inhibitors ; Thioguanine (FTK8U1GZNX)
    Language English
    Publishing date 2002-09-01
    Publishing country United States
    Document type Journal Article ; Research Support, U.S. Gov't, P.H.S.
    ZDB-ID 3019-3
    ISSN 1537-6613 ; 0022-1899
    ISSN (online) 1537-6613
    ISSN 0022-1899
    DOI 10.1086/342049
    Database MEDical Literature Analysis and Retrieval System OnLINE

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