• 제목/요약/키워드: Key Technology

검색결과 9,621건 처리시간 0.033초

Effect of Light with Different Wavelengths on Nostoc flagelliforme Cells in Liquid Culture

  • Dai, Yu-Jie;Li, Jing;Wei, Shu-Mei;Chen, Nan;Xiao, Yu-Peng;Tan, Zhi-Lei;Jia, Shi-Ru;Yuan, Nan-Nan;Tan, Ning;Song, Yi-Jie
    • Journal of Microbiology and Biotechnology
    • /
    • 제23권4호
    • /
    • pp.534-538
    • /
    • 2013
  • The effects of lights with different wavelengths on the growth and the yield of extracellular polysaccharides of Nostoc flagelliforme cells were investigated in a liquid cultivation. N. flagelliforme cells were cultured for 16 days in 500 ml conical flasks containing BG11 culture medium under $27{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$ of light intensity and $25^{\circ}C$ on a rotary shaker (140 rpm). The chlorophyll a, phycocyanin, allophycocyanin, and phycoerythrin contents in N. flagelliforme cells under the lights of different wavelengths were also measured. It was found that the cell biomass and the yield of polysaccharide changed with different wavelengths of light. The biomass and the yield of extracellular polysaccharides under the red or violet light were higher than those under other light colors. Chlorophyll a, phycocyanin, and allophycocyanin are the main pigments in N. flagelliforme cells. The results showed that N. flagelliforme, like other cyanobacteria, has the ability of adjusting the contents and relative ratio of its pigments with the light quality. As a conclusion, N. flagelliforme cells favor red and violet lights and perform the complementary chromatic adaptation ability to acclimate to the changes of the light quality in the environment.

Immunomodulatory Properties of Lactobacillus plantarum NC8 Expressing an Anti-CD11c Single-Chain Fv Fragment

  • Liu, Jing;Yang, Guilian;Gao, Xing;Zhang, Zan;Liu, Yang;Yang, Xin;Shi, Chunwei;Liu, Qiong;Jiang, Yanlong;Wang, Chunfeng
    • Journal of Microbiology and Biotechnology
    • /
    • 제29권1호
    • /
    • pp.160-170
    • /
    • 2019
  • The lactic acid bacteria species Lactobacillus plantarum (L. plantarum) has been used extensively for vaccine delivery. Considering to the critical role of dendritic cells in stimulating host immune response, in this study, we constructed a novel CD11c-targeting L. plantarum strain with surface-displayed variable fragments of anti-CD11c, single-chain antibody (scFv-CD11c). The newly designed L. plantarum strain, named 409-aCD11c, could adhere and invade more efficiently to bone marrow-derived DCs (BMDCs) in vitro due to the specific interaction between scFv-CD11c and CD11c located on the surface of BMDCs. After incubation with BMDCs, the 409-aCD11c strain harboring a eukaryotic vector pValac-GFP could lead to more efficient expression of GFP compared with wild-type strains shown by flow cytometry analysis, indicating the enhanced translocation of pValac-GFP from L. plantarum to BMDCs. Similar results were also observed in an in vivo study, which showed that oral administration resulted in efficient expression of GFP in both Peyer's patches (PP) and mesenteric lymph nodes (MLNs) within 7 days after the last administration. In addition, the CD11c-targeting strain significantly promoted the differentiation and maturation of DCs, the differentiation of $IL-4^+$ and $IL-17A^+$ T helper (Th) cells in MLNs, as well as production of $B220^+$ $IgA^+$ B cells in the PP. In conclusion, this study developed a novel DC-targeting L. plantarum strain which could increase the ability to deliver eukaryotic expression plasmid to host cells, indicating a promising approach for vaccine study.

Crystallization of a-Si Induced by Ni-Si oxide source

  • Meng, Z.;Liu, Z.;Zhao, S.;Wu, C.;Wong, M.;Kwok, H.;Xiong, S.
    • 한국정보디스플레이학회:학술대회논문집
    • /
    • 한국정보디스플레이학회 2008년도 International Meeting on Information Display
    • /
    • pp.985-988
    • /
    • 2008
  • Metal induced crystallization of a-Si with a source of Ni/Si oxide was studied. Its mechanism to induce crystallization was discussed. It was found that new source behaves an effect of self-released nickel and reducing nickel residua, so can provide a wider process tolerance; improve the uniformity and stability of TFTs.

  • PDF

Multilayered High-directional Waveguide Grating Antenna Based on Interleaved Etching for Optical Phased Arrays

  • Yang Bo;Qing Wang;Jinyu Wang;Yan, Cai;Wencheng Yue;Shuxiao Wang;Wei Wang;Mingbin Yu
    • Current Optics and Photonics
    • /
    • 제7권2호
    • /
    • pp.157-165
    • /
    • 2023
  • We propose a highly directional waveguide grating antenna for an optical phased array, achieving high directionality of more than 97% by interleaving the trenches with different etching depths in the silicon nitride layer, and adopting a multilayered structure. Meanwhile, the multilayered structure reduces the perturbation strength, which enables a centimeter-scale radiation length. The beam-steering range is 13.2°, with a wavelength bandwidth of 100 nm. The 1-dB bandwidth of the grating is 305 nm. The multilayered grating structure has a large tolerance to the fabrication variation and is compatible with CMOS fabrication techniques.

Prediction of flow boiling heat transfer coefficient in horizontal channels varying from conventional to small-diameter scales by genetic neural network

  • Zhang, Jing;Ma, Yichao;Wang, Mingjun;Zhang, Dalin;Qiu, Suizheng;Tian, Wenxi;Su, Guanghui
    • Nuclear Engineering and Technology
    • /
    • 제51권8호
    • /
    • pp.1897-1904
    • /
    • 2019
  • Three-layer back propagation network (BPN) and genetic neural network (GNN) were developed in this study to predict the flow boiling heat transfer coefficient (HTC) in conventional and small-diameter channels. The GNN has higher precision than BPN (with root mean square errors of 17.16% and 20.50%, respectively) and other correlations. The inputs include vapor quality x, mass flux G, heat flux q, diameter D and physical parameter φ, and the predicted flow boiling HTC is set as the outputs. Influences of input parameters on the flow boiling HTC are discussed based on the trained GNN: nucleate boiling promoted by a larger saturated pressure, a larger heat flux and a smaller diameter is dominant in small channels; convective boiling improved by a larger mass flux and a larger vapor quality is more significant in conventional channels. The HTC increases with pressure both in conventional and small channels. The HTC in conventional channels rises when mass flux increases but remains almost unaffected in small channels. A larger heat flux leads to the HTC growth in small channels and an increase of HTC was observed in conventional channels at a higher vapor quality. HTC increases inversely with diameter before dry out.

Ni Nanoparticle Anchored on MWCNT as a Novel Electrochemical Sensor for Detection of Phenol

  • Wang, Yajing;Wang, Jiankang;Yao, Zhongping;Liu, Chenyu;Xie, Taiping;Deng, Qihuang;Jiang, Zhaohua
    • Nano
    • /
    • 제13권11호
    • /
    • pp.1850134.1-1850134.10
    • /
    • 2018
  • Increasing active sites and enhancing electric conductivity are critical factors to improve sensing performance toward phenol. Herein, Ni nanoparticle was successfully anchored on acidified multiwalled carbon nanotube (a-MWCNT) surface by electroless plating technique to avoid Ni nanoparticle agglomeration and guarantee high conductivity. The crystal structure, phase composition and surface morphology were characterized by XRD, SEM and TEM measurement. The as-prepared Ni/a-MWCNT nanohybrid was immobilized onto glassy carbon electrode (GCE) surface for constructing phenol sensor. The phenol sensing performance indicated that Ni/a-MWCNT/GCE exhibited an amazing detection performance with rapid response time of 4 s, a relatively wide detection range from 0.01 mM to 0.48 mM, a detection limit of $7.07{\mu}M$ and high sensitivity of $566.2{\mu}A\;mM^{-1}\;cm^{-2}$. The superior selectivity, reproducibility, stability and applicability in real sample of Ni/a-MWCNT/GCE endowed it with potential application in discharged wastewater.

Study on the distribution law and influencing factors of pressure field distribution before exploitation in heavy oilfield

  • Zhang, Xing;Jiang, Ting T.;Zhang, Jian H.;Li, Bo;Li, Yu B.;Zhang, Chun Y.;Xu, Bing B.;Qi, Peng
    • Geomechanics and Engineering
    • /
    • 제18권2호
    • /
    • pp.205-213
    • /
    • 2019
  • A calculation model of reservoir pressure field distribution around multiple production wells in a heavy oil reservoir is established, which can overcome the unreasonable uniform-pressure value calculated by the traditional mathematical model in the multiwell mining areas. A calculating program is developed based on the deduced equations by using Visual Basic computer language. Based on the proposed mathematical model, the effects of drainage rate and formation permeability on the distribution of reservoir pressure are studied. Results show that the reservoir pressure drops most at the wellbore. The farther the distance away from the borehole, the sparser the isobaric lines distribute. Increasing drainage rate results in decreasing reservoir pressure and bottom-hole pressure, especially the latter. The permeability has a significant effect on bottom hole pressure. The study provides a reference basis for studying the dynamic pressure field distribution before thermal recovery technology in heavy oilfield and optimizing construction parameters.

기업 정보체계의 키 복구 기술 (Key Recovery Technology for Enterprise Information Infrastructure(EII))

  • 임신영;강상승;하영국;함호상;박상봉
    • 한국전자거래학회지
    • /
    • 제4권3호
    • /
    • pp.159-178
    • /
    • 1999
  • As Electronic Commerce is getting larger, the volume of Internet-based commerce by enterprise is also getting larger. This phenomenon applies to Internet EDI, Global Internet Business, and CALS information services. In this paper, a new type of cryptographic key recovery mechanism satisfying requirements of business environment is proposed. It is also applied to enterprise information infrastructure for managing employees' task related to handling official properties of electronic enterprise documents exchange. This technology needs to be complied to information management policy of a certain enterprise environment because behavior of cryptographic key recovery can cause interruption of the employees' privacy. However, the cryptographic key recovery mechanism is able to applied to any kind of information service, the application areas of key recovery technology must be seriously considered as not disturbing user's privacy It will depend on the policy of enterprise information management of a specific company.

  • PDF

Authentication and Key Agreement Protocol for Secure End-to-End Communications on Mobile Networks

  • Park, Jeong-Hyun;Kim, Jin-Suk;Kim, Hae-Kyu;Yang, Jeong-Mo;Yoo, Seung-Jae
    • 한국지능시스템학회:학술대회논문집
    • /
    • 한국퍼지및지능시스템학회 2003년도 ISIS 2003
    • /
    • pp.256-259
    • /
    • 2003
  • This paper presents mutual authentication scheme between user and network on mobile communications using public key scheme based on counter, and simultaneously shows key agreement between user and user using random number for secure communications. This is also a range of possible solutions to authentication and key agreement problem-authentication and key agreement protocol based on nonce and count, and secure end-to-end protocol based on the function Y=f(.)$\^$1/, C$\^$i/ is count of user I, and f(.) is one way function.

  • PDF

Differences in Physicochemical and Nutritional Properties of Breast and Thigh Meat from Crossbred Chickens, Commercial Broilers, and Spent Hens

  • Chen, Yulian;Qiao, Yan;Xiao, Yu;Chen, Haochun;Zhao, Liang;Huang, Ming;Zhou, Guanghong
    • Asian-Australasian Journal of Animal Sciences
    • /
    • 제29권6호
    • /
    • pp.855-864
    • /
    • 2016
  • The objective of this study was to compare the physicochemical and nutritional properties of breast and thigh meat from commercial Chinese crossbred chickens (817 Crossbred chicken, 817C), imported commercial broilers (Arbor Acres broiler, AAB), and commercial spent hens (Hyline Brown, HLB). The crossbred chickens, commercial broilers and spent hens were slaughtered at their typical market ages of 45 d, 40 d, and 560 d, respectively. The results revealed that several different characteristic features for the three breeds. The meat of the 817C was darker than that of the other two genotypes. The 817C were also characterized by higher protein, lower intramuscular fat, and better texture attributes (cooking loss, pressing loss and Warner-Bratzler shear force [WBSF]) compared with AAB and HLB. The meat of the spent hens (i.e. HLB) was higher in WBSF and total collagen content than meat of the crossbred chickens and imported broilers. Furthermore, correlation analysis and principal component analysis revealed that there was a clear relationship among physicochemical properties of chicken meats. With regard to nutritional properties, it was found that 817C and HLB exhibited higher contents of essential amino acids and essential/non-essential amino acid ratios. In addition, 817C were noted to have highest content of microelements whereas AAB have highest content of potassium. Besides, 817C birds had particularly higher proportions of desirable fatty acids, essential fatty acids, polyunsaturated/saturated and (18:0+18:1)/16:0 ratios. The present study also revealed that there were significant differences on breast meat and thigh meat for the physicochemical and nutritional properties, regardless of chicken breeds. In conclusion, meat of crossbred chickens has some unique features and exhibited more advantages over commercial broilers and spent hens. Therefore, the current investigation would provide valuable information for the chicken meat product processing, and influence the consumption of different chicken meat.