乐学会学——充分发挥学生的主体作用

在教学过程中,教师是主导,学生是主体,教师的教需通过学生主动而有效的学习,才能为学生所接受、消化、吸收,内化为他们自身的东西,从而有效地促进其身心素质的发展。因此,激发学生的学习动机、发展学生的学习能力,使学生乐学、会学、充分发挥其作为学习主体的能动作用,便成为教学方法改革的核心内容。

激发学习兴趣 发挥主体作用

在数学教学中,许多老师为了提高 学生的成绩,不厌其烦地讲解,精心地设计练习,甚至加班加点,结果还是收效甚微。原因何在?我认为根本的原因是:教师在教学中忽视了学生学习兴趣的培养和主体作用的发挥。 教学中我从尊重学生人格入手,通过各种渠道建立融洽的师生人际关系。在“亲其师,信其道”的础上,根据数学学科的特点,创设促使学生积极思维,探索解决数学问题的情境,使他们不断尝试成功,以形成对数学学习经久不衰的兴趣,并转化为稳固、持久的内在动力。

深基坑混凝土排桩支护及基坑壁逆作法施工技术

针对本地区地质条件,地层中有砾石和泥岩以及石灰岩的情况,考虑传统的支护方式不宜使用或成本太高。在传统支护方式的基础上继续创新,设计使用混凝土灌注排桩在基坑外侧作支护,另外主体结构采用逆作法施工,这样使外侧排桩与逆作基坑壁共同作为基坑支护系统,不但安全可靠,施工成本低。

社会效益的哲学思考

《辞海》里关于“效果”一词的解释是:“效果,人们行为产生的有效结果。”这解释我以为是正确的。效益,无疑也是人们的行为或从事某种活动的结果、成果。不那么严格和精确的话,可以说效益也就是效果,两者没有原则区别。但是,效益和效果,并非没有一点差别,为了说清这种差别,须要借助哲学上主体和客体的概念。 主体作出一种行为,从事一种活动;主体的行为、活动作用了客体,在客体上留下了痕迹,譬如使客体发生了某种变化。这就是主体作用的有效结果。这种结果就是效果,如图:

竞争优势与企业管理组织变革

竞争,是企业实力的较量。企业的竞争力来源于企业内在的竞争优势。而企业竞争优势的建立和发挥,与管理组织的不断变革紧密地联系在一起。本文试图通过对国有企业部分实例的分析,来阐述企业提高竞争优势的管理组织变革措施。

出版社发展战略与伽利略的狗

在一次访谈中,清华大学出版社社长李家强谈到出版发展战略时打了这么一个有意思的比方:“出版社的发展战略就像伽利略的狗,不能同比扩大。在一般人的经验常识里,大狗是小狗的放大。其实不然,伽利略做了一个实验,结果发现,一只小狗同比扩大后的大狗是一只身体很大,腿小得无法支撑身体的畸形狗。我们出版社在制订发展战略时。

Neutralizing antibodies in hepatitis C virus infection

Hepatitis C virus (HCV) is a major cause of hepatitis world-wide. The majority of infected individuals develop chronic hepatitis which can then progress to liver cirrhosis and hepatocellular carcinoma. Spontaneous viral clearance occurs in about 20%-30% of acutely infected individuals and results in resolution of infection without sequaelae. Both viral and host factors appear to play an important role for resolution of acute infection. A large body of evidence suggests that a strong, multispecific and long-lasting cellular immune response appears to be important for control of viral infection in acute hepatitis C. Due too the lack of convenient neutralization assays, the impact of neutralizing responses for control of viral infection had been less defined. In recent years, the development of robust tissue culture model systems for HCV entry and infection has finally allowed study of antibody-mediated neutralization and to gain further insights into viral targets of host neutralizing responses. In addition, detailed analysis of antibody-mediated neutralization in individual patients as well as cohorts with well defined viral isolates has enabled the study of neutralizing responses in the course of HCV infection and characterization of the impact of neutralizing antibodiesfor control of viral infection. This review will summarize recent progress in the understanding of the molecular mechanisms of antibody-mediated neutralization and its impact for HCV pathogenesis.

c-Fos enhances the survival of thymocytes during positive selection by upregulating Bcl-2

T cells are derived from progenitor thymocytes, of which only a minority receive the appropriate TCR signal, undergo positive selection and mature. Owing to the very short lifespan of thymocytes, the prerequisite for posi- tive selection is survival. TCR signal-induced Bcl-2 expression is believed to play a dominant role in the survival of positively selecting thymocytes, but how Bcl-2 is directly regulated is unknown. Here we report that the immediate early gene （IEG） c-Fos can stimulate the expression of Bcl-2, depending on a specific AP-l-binding site in the Bcl-2 promoter. In c-Fos transgenic （Fos-Tg） mice, c-Fos binds to this site and promotes the expression of Bcl-2. As a result, Fos-Tg thymocytes exhibited enhanced survival, and more mature single-positive （SP） thymocytes were generated, even on a unique TCR background. The TCR repertoire remained normal in Fos-Tg mice. Our results identified c-Fos as the mediator of the stimulatory effect of TCR signaling on Bcl-2 expression. Therefore, c-Fos, as an IEG, because of its early response ability, can quickly rescue the survival of short-lived thymocytes during positive selection. Our results provide novel insight into the mechanism regulating the survival of positively selecting thymocytes.

Dimension-Controllable and Photo-Responsive Supramolecular Organic Framworks through Cucurbit[8]uril-based Self-Assembly

Dimension-controllable supramolecular organic frameworks(SOFs)with aggregation-enhanced fluorescence are hierarchically fabricated through the host-guest interactions of cucurbit[8]uril(CB[8])and coumarin-modified tetraphenylethylene derivatives(TPEC).The three-dimensional layered SOFs could be constructed from the further stacking of two-dimensional mono-layered structures via simply regulating the self-assembly conditions including the culturing time and concentration.Upon light irradiation under the wavelength of 365 nm,the photodimerization of coumarin moieties occurred,which resulted in the transformation of the resultant TPECn/CB[8]4n two-dimensional SOFs into robust covalently-connected 2D polymers with molecular thickness.Interestingly,the supramolecular system of TPEC/CB[8]exhibited intriguing multicolor fluorescence emission from yellow to blue in the time range of 0-24 h at 365 nm irradiation,possessing potential applicability for photochromic fluorescence ink.

On Forgiveness and Justice＂ The Difficulties of Western Societies in Achieving a Coherent Discourse about Forgiveness＊

Forgiveness plays a main role in transitional justice, it is important to verify how forgiveness is justified by contemporary societies. No contemporary mentality can avoid the intuition that we are facing a reality that seems to belong to the field of religion. Hence, what interests us is precisely the moral consideration of this discussion. Facing the morality of forgiveness, the questions that are raised with respect to each type are： whether it is possible to forgive and whether one should forgive. The inherent contradiction of those who affirm the obligatory nature of forgiveness results in the supererogatory character of forgiveness. If all forgiveness is supererogatory in itself, then all forgiveness is always presented as something undeserved. Thus, we do not have supporting points to embark on a discourse about forgiveness. The result is that our political communities do not really know how to manage situations such as transitional justice.

Cu-SAPO-17:A novel catalyst for selective catalytic reduction of NOx

The high-temperature(HT) and low-temperature(LT) hydrothermal stabilities of molecular-sieve-based catalysts are important for the selective catalytic reduction of NOx with ammonia(NH3-SCR). In this paper, we report a catalyst, Cu2+ loading SAPO-17, synthesized using cyclohexylamine(CHA), which is commercially available and inexpensive and is utilized in NH3-SCR reduction for the first time. After systematic investigations on the optimization of Si and Cu2+ contents, it was concluded that Cu-SAPO-17-8.0%-0.22 displays favorable catalytic performance, even after being heated at 353 K for 24 h and at 973 K for 16 h. Moreover, the locations of CHAs, host–guest interaction and the Bronsted acid sites were explored by Rietveld refinement against powder X-ray diffraction data of as-made SAPO-17-8.0%. The refinement results showed that two CHAs exist within one eri cage and that the protonated CHA forms a hydrogen bond with O4, which indicates that the proton bonding with O4 will form the Bronsted acid site after the calcination.

The Analysis of Handel Variations as an Example for Brahms Variations

＂Variations＂ is one of the main musical forms in compositional process. Johannes Brahms is one of the most important Romantic composers that used this form. Variations and Fugue on a Theme by Handel, Op. 24, （Op. 24, 1862） is a piece that Johannes Brahms wrote for solo piano in a highly creative style, which was classically arranged. Brahms took the theme from an aria in George Frederic Handel＇s Harpsichord Suite in B-flat major, HWV 434 （1733）. In Handel＇s work, the original theme was turned into five variations. With the purpose of exploring chromatic possibilities after the piano was developed from harpsichord, Brahms made 25 magnificent variations with an extensive fugue in his work. The purpose of this work is to prepare an explanatory document for pianists who intend to perform this piece and who are not familiar with such work. Also, it is hoped that piano performers will find explanatory points in this composition （e.g., stylistic characteristics） through comparisons with his other variations and start performing it more frequently

Mechanical Design and Students＇ Creativity ＂Think outside the Box＂

A design project was used in junior level mechanical design course to challenge the students＇ creativity skills. Beside the theoretical foundation of the course subject, the students were introduced to several professional skills such as： decision making tools, technical review meetings, interaction with customers, and teamwork skills. The design challenge was to develop a bike rack to meet a list of technical and marketing constraints. Details of the project requirements are presented with a brief overview of the main project mentoring tools. Students＇ creativity is discussed through two samples of the student work. It was noticed that, the basic creativity skills of the students can be improved by using some of the training tools, however, the students vary in their response to this training.

Research on the New and Innovative Pattern of College Students＇ Ideological and Political Education under the Guidance and Perspective of the Core Values Theory

In this paper, we conduct in-depth research on the new and innovative pattern of college students＇ ideological and political education under the guidance and perspective of the core values theory. Implementation of ideological and political theory course construction will perfect the theory of education system. The dominance of socialist core values embodied in the noble moral and value pursuit of the process, it plays a major guiding role. Universities should give full play to the important role of ideological and political theory and adhere to Marxist theory as a guide and fully carry out the socialist core values education which will hold special meaning for students.

Effects of anions on the structural regulation of Zn‑salen‑modified metal‑organic cage

By virtue of a 3∶1 complementary coordination strategy,a chiral heteroleptic metal-organic cage that con-tains divergent functional units,Pd‑R(Zn),was precisely constructed via self-assembly of monodentate variational Zn-salen ligands RZn and NADH(reduced nicotinamide adenine dinucleotide)mimic modified tridentate ligands with square-planar Pd ions.UV-Vis and luminescence spectra experiments reveal that different anions could selec-tively interact with different sites of Zn-salen modified metal-organic cages to achieve the structural regulation of cage compound,by using the differentiated host-guest electrostatic interactions of counter ions with metal-organic hosts.Compared to other anions,the presence of chloride ions caused the most significant fluorescence emission enhancement of Pd‑R(Zn),meanwhile,the UV-Vis absorption band attributed to the salen aromatic backbone showed an absorption decrease,and the metal-to-ligand induced peak displayed a blue shift effect.Circular dichro-ism and ^(1)H NMR spectra further demonstrate that the introduction of chloride anions is beneficial to keeping a more rigid scaffold.