关于应用“实作—研究”型模式培养数学教师的研究

"实作—研究"型教师培训模式是促进数学教师由理论向行动转化的培训模式。该模式有利于受培训教师提高教学技能,改善教学策略和方法,进行教育研究。该模式具有操作性、双向性、针对性等特征。同时,实施该培训模式要求培训小组不能太大、指导教师具备丰富理论和实践经验,培训中必须具有硬件支持等条件。

How the Bcl-2 family of proteins interact to regulate apoptosis

Commitment of cells to apoptosis is governed largely by protein-protein interactions between members of the Bcl-2 protein family. Its three sub-families have distinct roles： the BH3-only proteins trigger apoptosis by binding via their BH3 domain to pro-survival relatives, while the pro-apoptotic Bax and Bak have an essential downstream role involving disruption of organellar membranes and induction of caspase activation. The BH3-only proteins act as damage sensors, held inert until their activation by stress signals. Once activated, they were thought to bind promiscuously to pro-survival protein targets but unexpected selectivity has recently emerged from analysis of their interactions. Some BH3-only proteins also bind to Bax and Bak. Whether Bax and Bak are activated directly by these BH3-only proteins, or indirectly as a consequence of BH3-only proteins neutralizing their pro-survival targets is the subject of intense debate. Regardless of this, a detailed understanding of the interactions between family members, which are often selective, has notable implications for designing anti-cancer drugs to target the Bcl-2 family.

Inhibitory effect of acetylshikonin on human gastric carcinoma cell line SGC-7901 in vitro and in vivo

AIM:To investigate the inhibitory effect of acetylshikonin on human gastric carcinoma cell line SGC-7901 and its mechanism. METHODS:MTT assay was used to assess the inhibitory effect of acetylshikonin on proliferation of SGC-7901 cells.Apopt osis-inducing effect was determined by flow cytometry and terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end-labeling with Hoechst staining.Expression of mRNA and protein in Bcl-2 and Bax was analyzed by reverse transcription-polymerase chain reaction and Western blot.Antitumor effect of acetylshikonin on a mouse SGC-7901 model was also determined. RESULTS:Forty-eight hours after treatment with acetylshikonin,MTT assay showed that acetylshikonin inhibited the proliferation of SGC-7901 cells in a dose-dependent manner.The half maximal inhibitory concentration of acetylshikonin to SGC-7901 cells was 0.428±0.07 mg/L.Cell shrinkage,nuclear pyknosis and chromatin condensation,which are the characteristics of cell apoptosis,were observed in treated SGC-7901 cells and the percentage of apoptosis increased in a dose-dependent manner.Acetylshikonin downregulated the expression of Bcl-2 and up-regulated the expression of Bax in the treated SGC-7901 cells compared with the controls.The experiment in vivo showed that 0.5,1,and 2 mg/kg of acetylshikonin significantly inhibited the growth of tumor in the mouse SGC-7901 model,with an inhibitory rate of 25.00%-55.76%. CONCLUSION:Acetylshikonin inhibits the growth of SGC-7901 cells in vitro and in vivo by inducing cell apoptosis.

Theoretical and Experimental Studies on Interactions of Cationic-Anionic Surfactants

Typical cationic and anionic surfactants were chosen and their interactions were calculated by quantum chemical method. Interaction energies are -0.2378 kJ·mol-1, -3.3394kJ·mol-1 and 0.1204kJ·mol-1 for the molecular pairs with fluocarbon and hydrocarbon chain: C4H10/C5H12, C4F10/C5H12, and C4F10 /C5F12, respectively. When hydrophilic group with cationic and anionicions is introduced, interaction energies are -287.40kJ·mol-1, -311.18kJ·mol-1 and -345.83kJ·mol-1. The results show that there is strong static interaction between cationic and anionic surfactants. It has been predicted that mixed monolayer may be formed and surface activity is enhanced favorably, especially for mixtures of cationic and anionic surfactants with fluocarbon and hydrocarbon chains. The anionic surfactants, sodium octadecylbenzenesulfonate perfluopolyetherbenzenesulonate(ANF-I) was synthesized, mixture effects of ANF-I with sodium octadecylbenzenesulfonate or dodecyldimethyl benzylammonium bromide were studied. The results indicate that the efficiency of mixing increased and the theoretical prediction was testified. These results can provide useful information for the design of new surfactants.

Design and experimental study of compensation fitting on the angle-tuned filters

For a 100 GHz DWDM angle-tuned filter with low polarization dependent loss,the insertion loss and the Gaussian-transformation tendency of the transmission spectrum will become more serious as the incident angle is increased. It is because of that the optical path and the transmission modes of the thin film filter will change when the incident angle is varied. According to the thin film matrix theory,the analysis model is established,the displacement change of the transmission field is simulated,and a dynamic compensation fitting is also designed and fabricated in the paper. The experimental results show that it can effectively reduce the insertion loss and the phenomenon of Gaussian process. Using the compensation fitting,the tunable range of the filter is at about 20 nm which coincides with the theoretical design.

Experimental Study on the Interspecific Interactions Between the Two Bloom-Forming Algal Species and the Rotifer Brachionus plicatilis

The interspecific interactions between the rotifer Brachionus plicatilis and two harmful algal blooms(HAB) species were investigated experimentally by single culture method. B. plicatilis population and the growth of the two algae were compared at different algal cell densities. The results demonstrated that the B. plicatilis obtained sufficient nutrition from Prorocentrum donghaiense to support net population increase. With exposure to 2.5×104 cells mL-1 of P. donghaiense,the number of B. plicatilis increased faster than it did when exposed to other four algal densities(5,10,15 and 20 ×104 cells mL-1),and the increase rate of B. plicatilis population(r) at this algal density was 0.104 ± 0.015 r d-1. Cell densities of P. donghaiense decreased due to the grazing of B. plicatilis. In contrast,Heterosigma akashiwo had an adverse effect on B. plicatilis population and its growth was largely unaffected by rotifer grazing. In this case,B. plicatilis population decreased and H. akashiwo grew at a rate similar to that of the control.

An experimental research of Weining granule in treating gastric precancerous lesions

Objective： To investigate potential therapeutic effects and mechanism of Weining granule in the treatment of gastric precancerous lesions. Methods： Sixty rats were randomly assigned to a blank group or a model group or to receive retinoic acid or high-, medium- or low- dose of Weining granule. General conditions of the animals were observed before and after treatment. Changes in gastric mucosal pathohistology, telomerase activity, proliferation index （PI） and apoptosis index （AI） were measured. Results： General conditions, including activity and eating, were improved in all Weining-granule-treated groups with the numbers of rats having intestinal metaplasia （IM）, atypical hyperplasia （ATP） or positive telomerase activity being significantly lower than those in the model group （P 〈 0.05 or P 〈 0.01）. Compared with the model group, all doses of Weining granule significantly decreased PI （P 〈 0.01） and increased AI （P 〈 0.05）. Conclusion： Weining granule may provide a therapeutic benefit for the treatment of gastric precancerous lesions by inhibiting telomerase activity and proliferation of gastric cancer cells and by accelerating their apoptosis.

Experimental study on the anticancer effect of curcumin on mouse of S180 in vivo

Objective ：To study curcumin＇s growth inhibitory effects and morphology changes on sarcoma graft＇s of S180 mouse, with further inquiry into the possible mechanisms, Methods： Thirty S180 mouse were randomly assigned into 3 groups ： saline group （blank control group）, Cytoxan group （positive control group） and curcumin group. The tumor inhibitory rates, the index of thymus and spleen,the growth of tumor and the change of pathology-morph, the index of apoptosis cells and morphology changes of apoptosis cells in the different groups were observed. Results： （1） Tumor＇s inhibitory rate in curcumin group and cytoxan group was 68, 32% and 70. 43%, respectively. Compared to blank control group, the 2 groups had significant elevated tumor inhibitory rate （P〈0.01）. （2） Thymus index of curcumin group did not have significant decrease compared to blank control group （P〉0.05）, （3） Under electroscope,curcumin group and positive control group had significant decrease in terms of growth of tumor, degree of infiltration of tumor, the number of nucleus fission, and blood vessels number compared to saline group （P〈0.05）, However, the degree of cell necrosis, the number of splenic segments and macrophage are increased significantly compared to negative group, （4） Accumulative score of apoptosis cell in curcumin group was significantly higher than other two groups（P〈0.05）. Conclusion： Internal organ study and ceil morphology observation show curcumin can effectively inhibit the growth and cause the death of sarcoma graft of S180 mouse without interference with thymus.

Experimental Study on External Low Frequency Vibration Influence on SPM

The influence of external low frequency (0-100 Hz) vibration on the tip-sample interaction in SPM is the main concern of this paper. A concept, vibration rejection ratio (VRR) proposed by Thompson et al, was investigated theoretically and experimentally. A concise theoretical background was introduced, a vibration stimulating and measuring system for SPM was built up, and an experimental research of the influence on SPM VRR was carried out with different SPM probes, samples, tip pre-loads and open/close loops of tip-sample interaction. It was proved both in theory and experiment that SPM VRR had correlations with the spring constant, the air damping constant, the effective mass of the cantilever, the contact spring constant and the contact damping constant between tip and sample. SPM's vibration rejecting ability can be improved by longer cantilever probe, softer sample surface, greater tip pre-load, and close-loop control for tip-sample interaction. More attention should be paid to a proper combination of the above parameters.

Making full use of action research in EFLT

Since 1970s, action research is well claimed in education. This article tries to give a brief introduction of some major relevant information about action research, and then it explores the significance of adopting action research in EFLT. Moreover, it proposes a possible way, namely collaborative action research in EFLT.

The exploration of the innovation mode of school enterprise cooperation in game analysis

school enterprise cooperation as a new mode of teaching. In the teaching practice has its advantages and disadvantages, how to obtain the maximum value in the pros and cons,It is the problems that enterprises and schools, both sides need to work together to solve. This article will carries on the domestic and foreign cooperation game research production analysis on the advantages and disadvantages in school enterprise cooperation and the analysis of its innovation. Emphasizing that between school and enterprises signed employment agreement, both parties together to develop personnel training plan, and the teachers, technology and other aspects to carry on the cooperation, using ＂agreement order type＂ talent culture.

AN EMPIRICAL STUDY ON WRITER'S BLOCK OF CHINESE EFL LEARNERS AT THE TERTIARY LEVEL

The present paper reports an empirical study on writer's block of Chinese EFL learners at the tertiary level in the mainland of P.R.China.Factor analysis approach was employed in the present study and the results of confirmatory factor analysis verified the model we gained.Three factors were found in writer's block of Chinese EFL learners:complexity,premature editing and attitudes.The results also showed that writer's block might be related to learners' lack of strategies in the writing process.Meanwhile,the blocked writers did not hold appropriate feelings and beliefs towards writing and teachers' evaluation on their writing.Accordingly,we suggest that we help develop learners' writing strategies and the teachers' evaluation be encouraging-oriented.Finally,suggestions for further research are raised.

Towards English Writing Research with Chinese Characteristics

This essay first reviews the history of English writing research in China, focusing on the way that though Chinese students negotiated multiple languages and cultures, nationalism and positivism oriented most teachers and researchers to treating native English speakers as the target audience of student writing. The essay then reviews the research reported in this special issue. These studies have advanced English writing research in China by examining writing at secondary, college, and graduate levels, the multi-dimensional feedback that student writers receive, and identity construction in student texts. The essay concludes by pointing out avenues for future research in this area.

Comparative observation of protective effects of earplug and barrel on auditory organs of guinea pigs exposed to experimental blast underpressure

To explore the protective effects of earplug and barrel on auditory organs of guinea pigs exposed to experimental blast underpressure （BUP）. Methods： The hearing thresholds of the guinea pigs were assessed with auditory brainstem responses （ABR）. The traumatic levels of tympanic membrane and ossicular chain were observed under stereo-microscope. The rate of outer hair cells （OHCs） loss was analyzed using a light microscope. The changes of guinea pigs protected with barrel and earplug were compared with those of the control group without any protection. Results： An important ABR threshold shift of the guinea pigs without any protection was detected from 8h to 14d after being exposed to BUP with a peak ranging from -64.5 kPa to -69.3 kPa （P〈0.01）. The rate of perforation of tympanic membrane reached 87.5 % and that of total OHCs loss was 19.46%± 5.38% at 14d after exposure. The guinea pigs protected with barrel and earplug had lower ABR threshold and total OHCs loss rate compared with the animals without any protection （P 〈0.01 ）. All of the tympanic membrane and ossicular chain of the protected animals maintained their integrities. Meanwhile, the guinea pigs protected with the barrel had lower ABR threshold and total OHCs loss rate than those with earplug （ P 〈 0.01 ）. Conclusions. The earplug and barrel have protective effects against BUP-induced trauma on auditory organs of the guinea pigs and the protective effects of barrel are better than those of earplug.