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61.
Through a modified agar well diffusion assay, antagonism of bacterium BS04 is tested. The data show that BS04 has antibiotic activity against phytopathogenic fungi and bacteria, including Phoma wasabiae Yokogi, Cochlibolus Heterostrophu, Exserohilum Turcicum, Curuvularia Lunata (Walk) Boed, Thantephorus cucumris, Fusarium graminearum, Xanthomonas axonopodis pv. Citri (Hasse) Dye and Xanthomonas zingiberi (Uyeda ) Savulescu. The products of bacterium BS04 can endure the treatment of a wide range of pH, and maintain the antibiotic activity after treatment of 100℃ for 30 min. The result suggests that bacterium BS04 has the potential as a promising biocontrol agent. In order to determine the taxonomic placement, the molecular identification of BS04 is performed. The comparative analysis of 16s rDNA sequences indicates that the 16s rDNA sequence of BS04 is highly homologous with sequences of typical Paenibacillus bacteria from the RPD library (from 92% to 99% ). And the constructed phylogenetic tree by using maximum-likelihood method with Bootstrap Trial 1000 proves that BS04 is subjected to Paenibacillus polymyxa.  相似文献   
62.
1 Introduction Transportation is a basic and indispensable element in social economic development Great achievements have been reached intransportation in China since the adoption of reform and opening policy in 1978 To meet the continuously increasing demands from the socioeconomic development for a harmony andwell-off living society, a national integrative transportation system instead of separate planning by individual transport mode has been under consideration to deal with old and emergin…  相似文献   
63.
The real-time performance of switched Ethernet is a hot research field. However, there isn't any effective modeling to describe it until now. Through analyzing the structure of classical switch, a switch model by network calculus is proposed, in which the data flow is divided into real-time flow and non real-time flow and the arrival curve, service curve, the max delay and max storage needed are got. The max delay provides theory direction for transmitting real-time data in switched Ethemet and the max storage provides the theory reference for constructing switch in real-time industrial Ethernet.  相似文献   
64.
In order to understand the interaction between fluid and particles, a two-way coupled three-dimensional mixing layer laden with particles at a Stokes number of 5 with different mass loadings is numerically studied. The pseudospectral method is used for the flow fluid and the Lagrangian approach is used to trace particles. The concept of computational particles is introduced to vary the mass loading of particles. The momentum coupling effect introduced by a particle is approximated to the point force. The simulation results show that the coherent structures are still dominant in the mixing layer, but the flow field is modulated by particles. The addition of the particles enhances the energy of all the Fourier modes with non-zero spanwise wavenumber, and the enhancement increases with the augment of the mass loading. A higher mass loading results in a lower energy at fundamental wavenumber and streamwise subharmonic Fourier mode of the fluid in the phase of Kelvin-Helmholtz rolling up, but for large-scale vortex structures pairing, the energy of the fluid increases as the mass loading increases. Similar trends can also be found in the developments of the turbulent kinetic energy and the momentum thickness.  相似文献   
65.
合成了目标配合物:碘化双 [3,4 二甲氧基苯甲醛缩氨基硫脲]合锌(II),其结构通过单晶X 射线衍射法确定。晶体属单斜晶系,C2/c空间群。配合物分子中,锌(II)与两个硫原子、两个碘原子配位形成轻微畸变的四面体结构,每一个3,4 二甲氧基苯甲醛缩氨基硫脲配体与锌离子处于同一平面内,在晶体中分子之间以氢键连接形成网状结构。  相似文献   
66.
Seasonal influence on the developmental ability of porcine embryos was studied by comparisons of the number of cumulus-oocytes-complexes (COCs) per ovary pair and meiotic maturation ability of oocytes in different seasons; and by the observations on developmental competence of the parthenogenetic oocytes and cloned embryos collected from different seasons. We found that the number of COCs per ovary pairs was significantly higher in spring compared to the other seasons (P<0.05). However, no significant difference was found in the rate of oocytes progressing to MⅡ in four seasons (P<0.05). In addition, the rate of blastocyst formation of parthenogenetic embryos in summer was obviously declined compared to the other seasons (P<0.05), and an increased blastocyst rate of cloned porcine embryos was found in spring compared to autumn and winter (P<0.05). The results suggest that there should be a seasonal influence on the developmental competence of porcine embryos.  相似文献   
67.
In this paper, a novel Passive Optical Network based on Optical Code Division Multiple Access (OCDMA-PON) is presented. The design of the Optical Line Terminator (OLT) and the Optical Network Unit (ONU) for the OCDMA-PON are studied in detail. The proposed OCDMA-PON combines the ad- vantages of PON and OCDMA technology and it can be applied to an optical access network with full services on demand, such as internet protocol, video on demand, tele-presence and high quality audio. Compared to other multiple access technologies, the proposed OCDMA-PON provides more ONU and assembly flexibly for PON. We analyze in detail the scalability and system transmission performance of such a network. Simulation results indicate that the proposed scheme is feasible and that the novel design can improve the scalability and transmission performance of the optical access networks.  相似文献   
68.
Gene expression of glutathione peroxidase 3 (ATGPX3) in response to osmotic stress was analyzed in Arabidopsis using ATGPX3 promoter-glucuronidase (GUS) transgenic plants. High levels of GUS ex- pression were detected under osmotic stress in ATGPX3 promoter-GUS transgenic plants. Compared with the wild type, the growth and development of ATGPX3 mutants (atgpx3-1) were more sensitive to mannitol. In addition, the expression of RD29A, ABI1, ABI2 and RbohD in atgpx3-1 was induced by ABA stress. These results suggest that ATGPX3 might be involved in the signal transduction of osmotic stress.  相似文献   
69.
Apigenin is a flavonoid widely distributed in fruits and vegetables. It possesses growth inhibitory properties against numerous cancer cell lines. However,the molecular mechanism(s) by which api-genin elicits its effects have not been fully elucidated. Here we studied whether apigenin inhibits growth and induces apoptosis in human gastric carcinoma cells. We showed that the flavonoid inhibited growth of the cells and caused apoptosis,as evidenced by DNA Ladder,cleavage of pro-caspase-3 in a time-dependent manner. Induction of apoptosis was dependent on inhibition of the PKB/Akt activity. We found that while apigenin had no effect on the expression of Akt and Bad,it inhibited specific phosphorylation of the two proteins that are associated with pro-survival mechanisms. We propose that this important flavonoid induces apoptosis in gastric cancer cells by inhibiting Akt activity. Since Akt is often activated in cancers,our findings may have clinical implications.  相似文献   
70.
The two-state reaction mechanism of CpCo(C_4H_4)with isocyanate on the triplet and singlet potential energy surfaces has been investigated at the B3LYP level.A study is described for the computation of spin-orbit coupling of triplet state of the minimal energy crossing point(CP)with their singlet states and of the zerofield splitting(ZFS)parameters of the triplet states,including the full one-and two-electron terms of the BreitPauli Hamiltonian.There are two key crossing points along this two-state reaction pathway.The first crossing point—CP2 exists near~1B.The reacting system will change its spin multiplicity from the triplet state to the singlet state near this crossing region.Although the spin-orbit coupling interaction and ZFS D-tensor of the CP2 region are very strong,the reaction system will occur the reverse intersystem crossing from T_1 to S_0.Therefore,its spin-flip efficiency may be lower.The second crossing point,CP3will again change its spin multiplicity from the singlet state to the triplet state in the Co-Cr bond activation pathway,leading to a decrease in the barrier height of~1TS(CF)from19.5 to 9.5 kcal/mol(1cal=4.182 J),and the efficiency of intersystem crossing from S_0 to T_1 is high because the larger spin-orbit coupling(SOC)matrix elements will result in the overpopulations of the three sublevels of T_1(3.30×10~(-1),3.32×10~(-1),and 3.38×10~(-1),respectively).  相似文献   
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