Kinematics Modeling and Experiments of Pectoral Oscillation Propulsion Robotic Fish

A robotic fish driven by oscillating fins, "Cownose Ray-I", is developed, which is in dorsoventrally flattened shape withouta tail. The robotic fish is composed of a body and two lateral fins. A three-factor kinematic model is established and used in thedesign of a mechanism. By controlling the three kinematic parameters, the robotic fish can accelerate and maneuver. Forwardvelocity is dependent on the largest amplitude and the number of waves in the fins, while the relative contribution of fin beatfrequency to the forward velocity of the robotic fish is different from the usual result. On the other hand, experimental results onmaneuvering show that phase difference has a stronger effect on swerving than the largest amplitude to some extent. In addition,as propulsion waves pass from the trailing edge to the leading edge, the robotic fish attains a backward velocity of 0. 15 m·s^-1.     

P13 K、p-AKT及HIF-1α在胰腺癌中的表达及意义

目的 检测P13K、p-AKT及HIF-1α三种蛋白在胰腺癌组织中的表达并探讨其与临床病理因素的关系及三者之间的相关性.方法 采用免疫组织化学SP法检测43例胰腺癌组织、9例胰腺炎组织和8例正常胰腺组织中P13K、p-AKT及HIF.1a三种蛋白的表达.结果 P13K、p-AKT的阳性表达主要位于肿瘤细胞胞浆,HIF-1α的阳性表达主要位于细胞核或细胞浆.P13K、p-AKT及HIF-1α在胰腺癌组织中的阳性表达率分别为62.79%、67.44%和69.77%,三者均显著高于在正常胰腺组织和慢性胰腺炎组织中的表达,差异有统计学意义(P<0.01).P13K、p-AKT及HIF-1α的异常表达均与胰腺癌的淋巴结转移和TNM分期有关(P<0.05),与患者的性别、年龄、部位、分化程度和病理分型无关(P>0.05).P13K、p-AKT及HIF-1α三者间的表达呈正相关.结论 P13K、p-AKT及HIF-1α的表达在胰腺癌的生长、浸润转移中起重要作用,P13K-AKT信号通路激活可能促进HIF-1α的表达.     

The murine pan T cell marker CD96 is an adhesion receptor for CD155 and nectin-1

The CD155 ligand CD96 is an immunoglobulin-like protein tentatively allocated to the repertoire of human NK receptors. We report here that the CD96/CD155-interaction is preserved between man and mouse although both receptors are only moderately conserved in amino acid sequence. Moreover, murine CD96 (mCD96) binds to nectin-1, a receptor related to CD155. Applying newly generated monoclonal antibodies specifically recognizing mCD96, an expression profile is revealed resembling closely that of human CD96 (hCD96) on cells of hematopoietic origin. A panel of anti-mCD96 but also recently established anti-mCD155 antibodies effectively prevents formation of CD96/CD155-complexes. This was exploited to demonstrate that the only available receptor for mCD96 present on thymocytes is mCD155. Moreover, T cell adhesion to insect cells expressing mCD155 is blocked by these antibodies depending on the T cell subtype. These results suggest a function of the CD96/CD155-adhesion system in T cell biology.     

Investigation of Micro-wear and Micro-friction Properties for Bionic Non-smooth Concave Components

Five kinds of 45^# steel samples with concave features on the surface were manufactured using Laser Texturing Technology (LIT). Optimum design theory was used to design the experiment, and a two-level orthogonal table-L16 (2^15) design was adopted , Micro-wear and micro-friction experienced by samples with concave surface features and samples with smooth surfaces were compared experimentally. The wear resistance of samples with concave surface features was increased most,and different surface morphologies had different effects on f~iction and wear properties.     

Fluorescence spectrometric study on the interaction of tamibarotene with bovine serum albumin

The interaction between tamibarotene and bovine serum albumin (BSA) was studied using fluorescence quenching technique and ultraviolet–visible spectrophotometry. The results of experiments showed that tamibarotene could strongly quench the intrinsic fluorescence of BSA by a dynamic quenching mechanism. The apparent binding constant, number of binding site and corresponding thermodynamic parameters at different temperatures were calculated respectively, and the main interaction force between tamibarotene and BSA was proved to be hydrophobic force. Synchronous fluorescence spectra showed that tamibarotene changed the molecular conformation of BSA. When BSA concentration was 1.00 × 10^?6 mol L^?1, the quenched fluorescence ΔF had a good linear relationship with the concentration of tamibarotene in the range 1.00 × 10^?6 to 12.00 × 10^?6 mol L^?1 with the detection limit of 6.52 × 10^?7 mol L^?1. Copyright © 2010 John Wiley & Sons, Ltd.     

<Emphasis Type="Italic">Pseudomonas stutzeri</Emphasis> as a novel biocatalyst for pyruvate production from<Emphasis Type="SmallCaps"> DL</Emphasis>-lactate

Pseudomonas stutzeri SDM oxidized dl-lactic acid (25.5 g l^-1) into pyruvic acid (22.6 g l^-1) over 24 h. Both NAD⁺-independent d-lactate dehydrogenase and NAD⁺-independent l-lactate dehydrogenase were found for the first time in the bioconversion of lactate to pyruvate based on the enzyme activity assay and proteomic analysis. Jianrong Hao and Cuiqing Ma contributed equally to this work     

Monoclonal antibodies against recombinant Der f 3 reveal localization of Der f 3 in the gut and faecal pellets of <Emphasis Type="Italic">Dermatophagoides farinae</Emphasis>

Home dust mite derived materials are known to be a major source of problematic inhalant allergens. The aim of this study was to determine the localization of the group 3 allergen, Der f 3, within Dermatophagoides farinae, in order to assess the relative importance of excreted materials and nonexcreted body components as allergen sources. Recombinant Der f 3 (rDer f 3) was expressed in bacteria and purified as an immunogen for production of monoclonal antibodies (mAb) against it. Dermatophagoides farinae mites and their faecal pellets were embedded in paraffin, and serial sections were immunoprobed with mAb clone 3D3 against Der f 3. D. farinae midgut mucosa, gut contents and faecal pellets were strongly immunopositive for Der f 3. Der f 3 immunoreactive products were not detected in any other internal organs of the mite. These results suggest that Der f 3 allergen may be synthesized in and secreted from the digestive tract and excreted from the mite’s body in the faecal pellets.     

Design, synthesis, and bioavailability evaluation of coumarin-based prodrug of meptazinol

Based on the known coumarin-based prodrug system, a new meptazinol (Z)-3-[2-(propionyloxy) phenyl]-2-propenoic ester (3) was designed and synthesized as prodrug to minimize the first-pass effect of meptazinol (1) and improve the oral bioavailability. The prodrug (3) showed a 4-fold increase in oral bioavailability over the parent drug meptazinol in rats.