“真”“活”“动”:让核心素养落地生根——高中政治公开课教学的实践思考

高中政治公开课活动中出现了一些不符合活动型课程要求、不利于培养学生核心素养的现象,引发了教师的思考。本文从理论层面简单阐述了开展活动型课程以及敦促核心素养落地的必要性,从现实层面分析当前公开课中存在的问题,并着重提出了解决之道:通过“真”“活”“动”,让核心素养真正落地并生根发芽,即通过“真”实课堂引领学生求真务实;营造“活”跃氛围,带领学生活学活用;注重“动”态过程,培养学生灵动思维。

Molecular Dynamics Simulation for the Effect of Chain Length of Spacer and Tail of Cationic Gemini Surfactant on the Complex with Anionic Polyelectrolyte

Interaction of anionic polyelectrolyte with cationic gemini surfactant has been investigated by coarse-grained molecular dynamics simulation.Polyelectrolyte facilitates the oppositely charged ionic surfactants to aggregate by suppressing the electrostatic repulsion between ionic head groups leading to the formation of micellar complex.With addition of surfactant,the conformation of polyion chain changes from stretched to random coiled to spherical,and at the same time more free micelles are formed by surfactants in mixtures.Increasing the length of spacer or tail chain in gemini surfactant will weaken its interaction with polyelectrolyte and simultaneously strengthen its tendency to self-assemble.The simulation results are consistent with experimental observations and reveal that the electrostatic interaction plays an important role in the interaction of polyelectrolyte with gemini sur- factant.

Comparison of the underestimation rate in cases with ductal carcinoma in situ at ultrasound-guided core biopsy: 14-gauge automated core-needle biopsy vs 11-gauge vacuum-assisted biopsy

Objective： The objective of this study was to compare the underestimation rate of invasive carcinoma cases with ductal carcinoma in situ （DCIS） at percutaneous ultrasound-guided core biopsies of breast lesions between 14-gauge automated core needle biopsy （ACNB） and 11-gauge vacuum-assisted biopsy （VAB）, and analyze the diagnostic advantages and insufficiencies in DCIS between this two methods, and to determine the relationship between the lesion type （masses or microcalcifications on radiological findings ） and DCIS underestimation rate. Methods： We collected 152 breast lesions which were diagnosed as DCIS by retrospectively reviewing data about ultrasound-guided biopsies of breast lesions （from February 2003 to July 2010）. There were 98 lesions in 95 patients by 14-gauge ACNB, and 54 lesions in 52 patients by 11-gauge VAB （The system used in this study called Mammatome, MMT）. The clinical and radiological findings were reviewed; meanwhile all the selected patients had histological results of the biopsies and follow-up surgeries which also achieved the reliable pathological results to compare with the biopsy results. The differences between two correlated histological results defined as underestimation, and the histological DCIS underestimation rates were compared between the two groups. According to the radiological characteristics, each group was classified into two subgroups （masses or micrecalcifications group）, and the differences between subgroups were also analyzed. Results： The DCIS underestimation rate was 45.9% （45/98） for 14-gauge ACNB and 16.6% （9/54） for MMT. According to the lesion type on ultrasonography, DCIS underestimation was 31.0% （26/84） in masses （43.1% using ACNB and 12.1% using MMT; P = 0.003） and 42.6% （29/68） in microcalcifications （48.9% using ACNB and 23,8% using MMT; P = 0,036）, Conclusion： The underestimation rate of invasive carcinoma in cases with DCIS at ultrasound-guided core biopsies is significantly higher for ACNB than for MMT. Furthermore, this difference does not alter among the two lesion types presented on ultrasonography. So ultrasound-guided VAB （MMT system） could be an effective and useful method for the diagnosis of DCIS lesions no matter what the lesion type is.

Phenomenological Simulation Study of Neuronal Activity Synchronization in 110 Elements Network

The phenomenon of activity synchronization in biological neural network is considered. Simulation of neurons dynamics in the 6-layer neural network with 110 elements in different regimes： regular spikes, chaotic spikes, regular and chaotic bursting, etc was performed. Izhykevich＇s phenomenological model that displays different types of activity inherent for real biological neurons was used for simulation. Space-time diagram for the entire network and raster plots for the whole structure and for each layer separately were built for visual inspection of neural network activity synchronization. Synchronization coefficients based on cross-correlation times of action potentials for all neurons pairs were calculated for the whole neural system and for each layer separately.

Efficiency of Combined Solar Thermal Heat Pump Systems

In this project, different combinations of solar energy and heat pump systems for preparation of DHW （domestic hot water） and space heating of buildings are analyzed through dynamic system simulations in TRNSYS （Transient System Simulation Program）. In such systems, solar thermal energy can be used, on one hand, directly to charge the buffer storage and, on the other hand, as heat source for the evaporator oftbe HP （heat pump）. In this work systems, in which solar heat is only used directly （parallel operation of solar and HP）, systems using the collectors also as a heat source for the HP are analyzed and compared to conventional air HP systems. With a combined parallel solar thermal HP system, the system performance compared to a conventional HP system can be significantly increased. Unglazed selectively coated collectors as source for the HP have the advantage that the collector can be used as an air heat exchanger. If solar radiation is available and the collector is used as source for the HP, higher temperatures at the evaporator of the HP can be achieved than with a conventional air HP system.

Frequent Applications of Organic Matter to Agricultural Soil Increase Fungistasis

Soil-borne plant pathogens are among the most important limiting factors for the productivity of agro-ecosystems. Fungistasis is the natural capability of soils to inhibit the germination and growth of soil-borne fungi in the presence of optimal abiotic conditions. The objective of this study was to assess the effects of different soil managements, in terms of soil amendment types and frequency of application, on fungistasis. For this purpose, a microcosm experiment was performed by conditioning a soil with frequent applications of organic matter with contrasting biochemical quality （i. e., glucose, alfalfa straw and wheat straw）. Thereafter, the fungistasis response was assessed on four fungi （Aspergillus niger, Botrytis cinerea, Pyrenoehaeta lycopersici and Trichoderma harzianum）. Conditioned soils were characterized by measuring microbial activity （soil respiration） and functional diversity using the BIOLOG EcoPlatesTM method. Results showed that irrespective of the fungal species and amendment types, frequent applications of organic matter reduced fungistasis relief and shortened the time required for fungistasis restoration. The frequent addition of easily decomposable organic compounds enhanced soil respiration and its specific catabolic capabilities. This study demonstrated that frequent applications of organic matter affected soil fungistasis likely as a result of higher microbial activity and functional diversity.