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Analysis of the Insect OS-D-Like Gene Family 总被引:9,自引:0,他引:9
Wanner KW Willis LG Theilmann DA Isman MB Feng Q Plettner E 《Journal of chemical ecology》2004,30(5):889-911
Insect OS-D-like proteins, also known as chemosensory (CSP) or sensory appendage proteins (SAP), are broadly expressed in various insect tissues, where they are thought to bind short to medium chain length fatty acids and their derivatives. Although their specific function remains uncertain, OS-D-like members have been isolated from sensory organs (including the sensillum lymph in some cases), and a role in olfaction similar to that of the insect odorant binding proteins (OBP) has been suggested for some. We have identified 15 new OS-D-like sequences: four from cDNA clones described herein and 11 from sequence databases. The os-d-like genes from the Anopheles gambiae, Apis mellifera, Drosophila melanogaster, and Drosophila pseudoobscura genomes typically have single, small introns with a conserved splice site. Together with all family members entered on GenBank, a total of 70 OS-D-like proteins, representing the insect orders Diptera, Dictyoptera, Hymenoptera, Lepidoptera, Orthoptera, and Phasmatodea, were analyzed. A neighbor joining distance phenogram identified several protein similarity classes that were characterized by highly conserved sequence motifs, including (A) N-terminal YTTKYDN(V/I)(N/D)(L/V)DEIL, (B) central DGKELKXX(I/L)PDAL, and (C) C-terminal KYDP. In contrast, three similarity classes were characterized by their diversion from these conserved motifs. The functional importance of conserved amino acid residues is discussed in relation to the crystal and NMR structures of MbraCSPA6. 相似文献
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带挠性附件航天器可以用含小摄动参数的多时标非线性系统进行描述,而目前的控制方法大多针对多时标线性系统,要求模型精确已知.为解决存在不确定性的带挠性附件航天器的跟踪问题,提出一种基于模糊奇异摄动模型的自适应控制器,采用鲁棒控制和自适应控制理论相结合的方法进行设计,由反馈项、自适应项和鲁棒控制项组成,反馈项的增益采用线性矩阵不等式(LMI)方法求解,自适应项用于减小系统的跟踪误差,鲁棒项用于保证系统的闭环稳定性.稳定性证明采用Lyapunov合成方法完成.该控制器适用于模型带有不确定性的多时标非线性系统的跟踪控制.由于采用了自适应方法消除系统不确定性,能够减少鲁棒控制方法带来的保守性.在带挠性附件航天器的跟踪控制中的应用验证了其有效性. 相似文献
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为探讨密度分层流中附体对潜艇周围流场及阻力特性的影响,基于雷诺平均方程建立一种用于模拟密度分层流中水下潜体航行特征的计算流体力学模型。采用SUBOFF潜艇模型进行收敛性研究,并与实验结果进行对比验证数值模型的精确性;采用该模型模拟得到加装不同附体工况下的潜艇以不同航速航行时的水动力特性,并结合压力变化分析相关结果产生的原因。结果表明:附体对分层流中潜艇水动力特性的影响与航速高低有关;在弗劳德数为0.5附近,潜艇兴波阻力系数达到最高;附体带来的潜艇表面曲率突变会引起较大的压力变化;所建模型展示了潜艇的航行尾迹特征,并对密度分层流中水下潜体运动问题模拟方法的选取及潜艇附体的优化设计具有一定参考价值。 相似文献
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太阳帆板驱动中堵转现象的分析 总被引:1,自引:1,他引:0
空间飞行器太阳帆板的振动与其驱动系统的非线性耦合,会使有效驱动力矩不足以克服摩擦阻力,导致太阳帆板驱动系统发生堵转,本文深入分析了产生这种现象的原因,提出了避免措施。 相似文献
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为了将自主研发的单体复合船型从几百吨级向千吨级和4千吨级船舶上推广应用,通过在3个不同吨级的单体船艏底部加装减纵摇组合附体形成了3个单体复合船型,对各单体复合船型和原船型进行了模型水池规则波和静水阻力试验,对比试验结果,分析组合附体对各单体复合船型纵向运动性能和静水阻力性能的影响.结果表明:合理的组合附体形式、尺度及艏鳍、半潜体与主船体的水动力布局可以使单体复合船型静水阻力与原船型相比影响不大,而其在波浪中的纵向运动性能得到较大改善.证明了单体复合船型在4千吨级以下船舶上应用是可行的. 相似文献
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In this paper, the chaotic dynamics in an attitude transition maneuver of a slosh-spacecraft coupled with flexible appendage in going from minor axis to major axis spin under the influence of dissipative effects due to fuel slosh and a small flexible appendage constrained to only torsional vibration is investigated. The slosh-spacecraft coupled with flexible appendage in attitude maneuver carrying a sloshing liquid is considered as multi-body system with the sloshing motion modeled as a spherical pendulum. ... 相似文献
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Daisuke Horita Masato Yoshimoto Hiroaki Todo 《Drug development and industrial pharmacy》2014,40(3):345-351
Objective: Skin appendages including hair follicles (hfs) and the stratum corneum (sc) are beginning to be recognized as important permeation pathways for the skin permeation of drugs, but their detailed role is not yet clear. To investigate the contribution of hfs to drug permeation, we conducted skin permeation tests by controlling the hf contribution with a hf-plugging method.Method: Lidocaine (LC) and fluorescein isothiocyanate-dextran 4?kDa (FD-4) were selected as model drugs and pig ear skin was used as model skin.Results: Skin permeabilities of ionized LC and FD-4 decreased with hf-plugging, whereas no change was observed for the skin permeation of unionized LC. A fairly good correlation was found for ionized LC and FD-4 between skin permeability and the number of hfs plugged. Permeation parameters of model drugs for both skin pathways were calculated utilizing Fick's second law of diffusion. Consequently, the sc pathway could highly contribute to the permeation of unionized LC, since unionized LC shows markedly high partition to the sc. In contrast, the hf pathway could contribute to the permeation of ionized LC and FD-4, since these had high distributions to the hf pathway in spite of its very small surface area relative to whole skin surface area.Conclusion: The hf pathway must be important for the skin permeation of ionized compounds and hydrophilic high molecular compounds. hf-plugging is also a useful method for assessing the skin permeability of compounds through the hf pathway. 相似文献
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Jussi V. Leinonen Pivi Leinikka Miikka Tarkia Milla Lampinen Avishag K. Emanuelov Ronen Beeri Esko Kankuri Eero Mervaala 《International journal of molecular sciences》2022,23(9)
The left atrial appendage (LAA) of the adult heart has been shown to contain cardiac and myeloid progenitor cells. The resident myeloid progenitor population expresses an array of pro-regenerative paracrine factors. Cardiac constructs have been shown to inhibit deleterious remodeling of the heart using physical support. Due to these aspects, LAA holds promise as a regenerative transplant. LAAs from adult mT/mG mice were transplanted to the recipient 129X1-SvJ mice simultaneously as myocardial infarction (MI) was performed. A decellularized LAA patch was implanted in the control group. Two weeks after MI, the LAA patch had integrated to the ventricular wall, and migrated cells were seen in the MI area. The cells had two main phenotypes: small F4/80+ cells and large troponin C+ cells. After follow-up at 8 weeks, the LAA patch remained viable, and the functional status of the heart improved. Cardiac echo demonstrated that, after 6 weeks, the mice in the LAA-patch-treated group showed an increasing and statistically significant improvement in cardiac performance when compared to the MI and MI + decellularized patch controls. Physical patch-support (LAA and decellularized LAA patch) had an equal effect on the inhibition of deleterious remodeling, but only the LAA patch inhibited the hypertrophic response. Our study demonstrates that the LAA transplantation has the potential for use as a treatment for myocardial infarction. This method can putatively combine cell therapy (regenerative effect) and physical support (inhibition of deleterious remodeling). 相似文献