Nicotine is not only a major component in tobacco but is also a survival agonist that inhibits apoptosis induced by certain agents including chemotherapeutic drugs. Here, we first showed that nicotine inhibits cisplatin-induced apoptosis in NCI-H446 cells. An MTT assay, Annexin V-FITC staining, RT-PCR, and Western blot were applied to identify the viability of cells, stages of apoptosis, mRNA and signaling proteins expression, respectively. First, we observed that nicotine induced no significant apoptosis when used alone and promoted cell proliferation at a low concentration or for a short time, but the opposite was observed at a high concentration or for a long time. In addition, an increase in XIAP and Survivin mRNA or protein was observed. Next, when combined with cisplatin, growth inhibition rates were concentration dependent, decreased to the lowest level at first, but later climbed to the highest point. Furthermore, nicotine inhibited apoptosis induced by cisplatin and caused a concentration-dependent increase in both XIAP and Survivin mRNA or protein. Moreover, the apoptotic effect of the combination group was obviously higher than that of nicotine used alone at the same nicotine concentration and lower than that of cisplatin used alone at the same cisplatin concentration. These studies suggest that exposure to nicotine might negatively impact the apoptotic potential of chemotherapeutics.

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Aimed at project Instructional Courseware Design Using Geometrical Painting Method which is an sample of multimedia courseware, an suggestion was made that design should be directed by appropriate teaching and learning theory, bring forth all materials to learner through appropriate technology, making the learner to be able to join into the whole process of learning, to practice all the related technique in time, so that the learner could to be learned soon. Through this process, the learner not only could learn the knowledge it self, but also the method to solve problems in the real world.

This paper presents a structural design of a methane sensor based on the principle of infrared detection, and designs a program of the experimental calibration. In the conditions of laboratory, different concentrations of methane gas were detected. A concentration inversion formula was proposed by the segmented least-square fitting method. The sensor can measure concentrations of methane in a real-time and accurate way, it contains the functions that digital display and sound and light alarm. The results show that a full-scale concentrations of methane gas can be detected, when the concentration range is in 0-10%, the absolute error is less than 0.09%; when it is more than 10%, the absolute error is less than 0.2%, the response time is less than 15s.