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962.
Members of tripartite motif (TRIM) proteins in mammals play important roles in multiple cellular processes in the immune system. In the present study we have obtained the chicken TRIM39 with the insertion of a base A at position 1006 bp, compared to the sequence in the NCBI database (Accession No: NM 001006196), which made TRIM39 fulfill the TRIM rule of domain composition with both PRY, and SPRY domains. The open reading frame consisted of 1392 bp encoding 463 amino acid residues. The amino acid sequences of TRIM39 protein in mammals were highly similar (from 91.48% to 99.61%), while chicken TRIM39 had relatively low homology with mammals (from 29.2% to 39.59%). Real time RT-PCR indicated that the mRNA expression level of TRIM39 was the highest in spleen, with a lower expression in liver, brain, and lung, suggesting it might be an important protein participating in the immune system. 相似文献
963.
运用机构学方法分别对四点式和五点式斜排肘杆机构进行运动及力学性能分析,建立2种肘杆机构数学模型。借助MATLAB程序与ADAMS软件分别对2种肘杆机构进行计算和运动学仿真,并对其运动曲线进行分析。结果表明,四点斜排肘杆机构的动模板速度、加速度及机构力放大比均优于五点斜排肘杆机构,为注塑机肘杆机构的设计与选型提供了理论依据。 相似文献
964.
965.
对多重富集低 NOx 煤粉燃烧器的结构及特点进行了分析 ,初步阐述了这种燃烧器的低负荷稳燃和低 NOx 排放原理 ,并进行了一系列冷态模化实验 ,研究了燃烧器结构和气流等因素对这种燃烧器性能 ,即浓淡风比、阻力系数的影响 .实验结果表明 ,档块间开度对燃烧器阻力损失影响显著 ,开度增加可使燃烧器阻力损失降低 ,浓淡风比减小 ,但双档块开度过多 ,会使加粉时煤粉气流的浓淡分离效果变差 ;浓淡风比受燃烧器浓淡侧阻力平衡决定 ,为此 ,必须在浓侧设置阻力调节器 ,满足阻力特性和风量平衡的多重要求 ,根据实验结果得到了优化的燃烧器结构 . 相似文献
966.
An improved allelopathic correlation between phytotoxicity measured in root growth bioassay upon annual ryegrass (Lolium rigidum Gaud.) and the concentrations of a selection of dynamically produced allelochemicals quantified in the root exudates of cv. Khapli wheat (Triticum turgidum ssp. durum (Desf.) Husn.) monitored during the first 15 days of wheat seedling growth in a sterile, agar–water medium, has been established. Changes over the 15-day growth period in the quantities of five exuded benzoxazinones and seven phenolic acids were measured simultaneously using GC/MS/MS. Substantiating pure compound dose–response measurements were conducted over a range of concentrations for the putative allelochemicals within the wheat exudates. One synergism-based proposal using the monitored compounds to explain the observed low-exudate-concentration phytotoxicity was explored, but was found to be experimentally inadequate. 相似文献
967.
Høiberg-Nielsen R Tofteng Shelton AP Sørensen KK Roessle M Svergun DI Thulstrup PW Jensen KJ Arleth L 《Chembiochem : a European journal of chemical biology》2008,9(16):2663-2672
De novo design and chemical synthesis of proteins and their mimics are central approaches for understanding protein folding and accessing proteins with novel functions. We have previously described carbohydrates as templates for the assembly of artificial proteins, so-called carboproteins. Here, we describe the preparation and structural studies of three alpha-helical bundle carboproteins, which were assembled from three different carbohydrate templates and one amphiphilic hexadecapeptide sequence. This heptad repeat peptide sequence has been reported to lead to 4-alpha-helix formation. The low resolution solution structures of the three carboproteins were analyzed by means of small-angle X-ray scattering (SAXS) and synchrotron radiation circular dichroism (SRCD). The ab initio SAXS data analysis revealed that all three carboproteins adopted an unexpected 3+1-helix folding topology in solution, while the free peptide formed a 3-helix bundle. This finding is consistent with the calculated alpha-helicities based on the SRCD data, which are 72 and 68 % for two of the carboproteins. The choice of template did not affect the overall folding topology (that is for the 3+1 helix bundle) the template did have a noticeable impact on the solution structure. This was particularly evident when comparing 4-helix carboprotein monomers with the 2x2-helix carboprotein dimer as the latter adopted a more compact conformation. Furthermore, the clear conformational differences observed between the two 4-helix (3+1) carboproteins based on D-altropyranoside and D-galactopyranoside support the notion that folding is affected by the template, and subtle variations in template distance-geometry design may be exploited to control the solution fold. In addition, the SRCD data show that template assembly significantly increases thermostability. 相似文献
968.
969.
随着城市机动车保有量的不断增加,交通拥堵问题变得日益严重。作为一个有效的方法,模型预测控制(MPC)已经被应用于城市交通路网的控制中。然而由于需要在线进行优化,模型预测控制的计算负荷巨大,限制了其在对实时性要求比较高的场景中的应用。针对该问题,基于存储转发模型将显式模型预测控制(EMPC)引入大型交通路网的交通信号控制问题中。EMPC将多参数规划理论引入到线性时不变系统的约束二次优化控制问题的求解中,通过离线计算得到对应每个状态分区上的状态反馈最优显式控制律。实验结果显示,由于将在线优化过程转变为查表过程,EMPC可以显著提升交通信号控制的效率。 相似文献
970.