Detection of EGFR on living human gastric cancer BGC823 cells using surface plasmon resonance phase sensing

Label-free and real-time information acquisition of molecular phenotype and its function on living cells plays a significant role in disease diagnosis and drug development. In this paper, SPR phase sensing was applied to monitor the interactions between EGFR antibody, EGFR1, and membrane proteins EGFR on living human gastric cancer BGC823 cells. When 50 μg/mL EGFR1 was added onto the fixed cells chip and the living cells chip, a significant difference in the binding amount could be observed from the immunofluorescence images. Quantitative results were obtained by following SPR detection, which were 722 RU and 438 RU, respectively. On the same living cells chip, SPR detection also showed markedly different results of cellular responses when it was stimulated by EGFR1 at different concentrations, such as adhesion and/or morphology variation, revealing the EGFR1's cytotoxic effect on the BGC823 cells. The results demonstrate SPR phase sensing is capable of real-time detection of molecular interactions and cellular responses on living cells, and suggest that further studies on the mechanism and the technique may allow SPR sensing become a powerful tool not only for the basic research of cell biology, but also for medical diagnosis and drug development.     

一种连续变焦距电视的变倍补偿机构设计

为了实现电视的焦距连续变化,设计了一种连续变焦距电视的变倍补偿机构。提出了一种提高变倍、补偿机构运动精度的方法,实测两机构直线运动精度均为15″。通过靶场试验证明连续变焦距电视的变倍补偿机构的运动精度满足电视捕获、跟踪目标的精度要求,两直线滑轨平行度调整机构设计、加工简单,可以在其它直线运动机构中得到推广应用。     

盾构机吊装安全控制技术研究

盾构机吊装一般采用解体后单件吊装,但单件最大重量仍然在100 t左右,加上在深基坑边缘作业,周边空间又十分狭小,是高风险的作业活动.文章根据苏州近年来较丰富的吊装经验,总结了盾构机吊装的技术与安全控制方法,供生产实践中参考.     

Optimization of the production of thiocarbohydrazide using the Taguchi method

BACKGROUND: The Taguchi method, a powerful tool for the optimization of quality, was used to improve the yield of thiocarbohydrazide in its synthetic process. An orthogonal array was selected to analyze the effects of the process factors, i.e. reflux time, molar ratio of hydrazine to carbon disulfide and reflux temperature. Experiments were undertaken to confirm the effectiveness of the Taguchi method. RESULTS: Through this study, the main factors that affect the yield of thiocarbohydrazide were found, together with the optimal factor levels. It was shown that the reflux temperature was the most significant factor affecting the yield of thiocarbohydrazide, followed by the molar ratio of hydrazine to carbon disulfide. The optimum factor levels were a reflux time of 6 h, molar ratio of hydrazine to carbon disulfide 3.0 and reflux temperature 70 °C. A 92.3% yield of thiocarbohydrazide was obtained at these optimal factor levels. CONCLUSIONS: The yield of thiocarbohydrazide can be significantly improved by optimization of the synthetic process factors. The Taguchi method provided a systematic and efficient methodology for this optimization, with far less effort than would be required for most other optimization techniques. Copyright © 2010 Society of Chemical Industry     

输电铁塔岩石锚杆基础锚固深度的理论计算及探讨

锚固深度的合理选取是输电铁塔岩石锚杆基础设计的一项关键内容。基于荷载传递机理建立锚杆受力平衡微分方程,推导出输电铁塔锚杆基础充分考虑岩体特性时锚固深度的理论计算公式。基于此,通过引入岩体软弱性系数η,考虑不同岩体特征情况下的锚杆基础进行数值计算分析,给出了相应的锚固理论深度建议取值。     

对《关于分析设计法中应力强度准则P_m+P_b≤1.5[σ]的讨论》一文的商榷

在全面学习ASME规范及其制定依据的基础上,对《关于分析设计法中应力强度准则Pm+Pb≤1.5[σ]的讨论》一文中所定出的设计曲线方程以及认为ASME规范中Pm+Pb应力强度准则的安全裕度并不总能保证≥1.5的论点提出疑问。认为:该文对Pm+Pb以及Pm应力强度限制条件含义的理解恐和规范规定有所出入;该文所提出的3个修正方案也是不必要的。     

Immune-Pineal Axis: Nuclear Factor κB (NF-κB) Mediates the Shift in the Melatonin Source from Pinealocytes to Immune Competent Cells

Pineal gland melatonin is the darkness hormone, while extra-pineal melatonin produced by the gonads, gut, retina, and immune competent cells acts as a paracrine or autocrine mediator. The well-known immunomodulatory effect of melatonin is observed either as an endocrine, a paracrine or an autocrine response. In mammals, nuclear translocation of nuclear factor κ-light-chain-enhancer of activated B cells (NF-κB) blocks noradrenaline-induced melatonin synthesis in pinealocytes, which induces melatonin synthesis in macrophages. In addition, melatonin reduces NF-κB activation in pinealocytes and immune competent cells. Therefore, pathogen- or danger-associated molecular patterns transiently switch the synthesis of melatonin from pinealocytes to immune competent cells, and as the response progresses melatonin inhibition of NF-κB activity leads these cells to a more quiescent state. The opposite effect of NF-κB in pinealocytes and immune competent cells is due to different NF-κB dimers recruited in each phase of the defense response. This coordinated shift of the source of melatonin driven by NF-κB is called the immune-pineal axis. Finally, we discuss how this concept might be relevant to a better understanding of pathological conditions with impaired melatonin rhythms and hope it opens new horizons for the research of side effects of melatonin-based therapies.     

Resonant frequency of an air gap tuned circular disc microstrip antenna

In this study, the formulation and the computation of the resonant frequency of an air gap tuned circular disc microstrip antenna are simplified, with improved accuracy, by using a new and very simple effective permittivity expression which is valid for thin and thick gaps. Very good agreement between the theoretical and the experimental resonant frequency values is obtained for the various structural parameters and operational modes.     

“无功补偿”装置容量的确定及应用

由于当下生活用电量的持续增加,供电系统出现供不应求的现状。该文基于现实没有功率因数补偿装置相配套的情况,通过改善电压品质,成功研发了一种新的满足供电需求的变压器供电系统。     

3D adaptive finite element modeling of non-planar curved crack growth using the weighted superconvergent patch recovery method

In this paper, an adaptive finite element analysis is presented for 3D modeling of non-planar curved crack growth. The fracture mechanical evaluation is performed based on a general technique for non-planar curved cracks. The Schollmann’s crack kinking criterion is used for the process of crack propagation in 3D problems. The Zienkiewicz-Zhu error estimator is employed in conjunction with a weighted SPR technique at each patch to improve the accuracy of error estimation. Applying the proposed technique to 3D non-planar curved crack growth problems shows significant improvements particularly at the boundaries and near crack tip regions. Several numerical examples are presented to illustrate the robustness of the proposed technique.