Unexpected Realities: Lessons from China’s New English Textbook Implementation

Although studies have been done in China’s large cities on education policy issues, research is lacking on China’s smaller towns, which are more indicative of the situations throughout China. This article presents lessons learned from studying Chinese English teachers at four different schools that were adopting new English textbooks, in accordance with revised national education policy. Using conflict theory and social action theory as an analytical lens, and combining ethnographic and naturalistic inquiry as research methods, the article reports on the conflicts that the Chinese English teachers confronted as they were adopting the new English textbooks at the classroom level. Analysis of the implementation conflict resulted in lessons learned related to the influence of the traditional cultural and education structures, the impact of policy implementation contexts, and the availability of support systems for teachers. The lessons indicate that future education policymakers in both China and the United States need to be mindful of obstacles that teachers struggle to overcome when implementing new policies

Expectile Matrix Factorization for Skewed Data Analysis

Matrix factorization is a popular approach to solving matrix estimation problems based on partial observations. Existing matrix factorization is based on least squares and aims to yield a low-rank matrix to interpret the conditional sample means given the observations. However, in many real applications with skewed and extreme data, least squares cannot explain their central tendency or tail distributions, yielding undesired estimates. In this paper, we propose \emph{expectile matrix factorization} by introducing asymmetric least squares, a key concept in expectile regression analysis, into the matrix factorization framework. We propose an efficient algorithm to solve the new problem based on alternating minimization and quadratic programming. We prove that our algorithm converges to a global optimum and exactly recovers the true underlying low-rank matrices when noise is zero. For synthetic data with skewed noise and a real-world dataset containing web service response times, the proposed scheme achieves lower recovery errors than the existing matrix factorization method based on least squares in a wide range of settings.Comment: 8 page main text with 5 page supplementary documents, published in AAAI 201

Highly excited and exotic fully-strange tetraquark states

Some hadrons have the exotic quantum numbers that the traditional $\bar q q$ mesons and $qqq$ baryons can not reach, such as $J^{PC} = 0^{--}/0^{+-}/1^{-+}/2^{+-}/3^{-+}/4^{+-}$, etc. We investigate for the first time the exotic quantum number $J^{PC}=4^{+-}$, and study the fully-strange tetraquark states with such an exotic quantum number. We systematically construct all the diquark-antidiquark interpolating currents, and apply the method of QCD sum rules to calculate both the diagonal and off-diagonal correlation functions. The obtained results are used to construct three mixing currents that are nearly non-correlated, and we use one of them to extract the mass of the lowest-lying state to be $2.85^{+0.19}_{-0.22}$ GeV. We apply the Fierz rearrangement to transform this mixing current to be the combination of three meson-meson currents, and the obtained Fierz identity suggests that this state dominantly decays into the $P$-wave $\phi(1020) f_2^\prime(1525)$ channel. This fully-strange tetraquark state of $J^{PC}=4^{+-}$ is a purely exotic hadron to be potentially observed in future particle experiments.Comment: 8 pages, 7 figures, 1 table, revised version to be published in EPJ

Anti-cancer activity of Aster tataricus on SCC-9 human oral squamous carcinoma

Background: Oral squamous carcinoma is a head and neck cancer, which is one of the types of malignant cancers. Present study evaluates the anticancer activity of Aster tataricus (AT) on SCC-9 human oral squamous carcinoma.Materials and Methods: Ethanol extract of AT was prepared by a standard procedure of maceration. AT extract was used in different concentrations like 10, 20, 40, 80, 160, 320 and 640 μg/ml for the evaluation of its anticancer activity. Effect of AT extract on SCC9 cells were observed by microscope and cytotoxicity by 3-(4, 5-Dimethylthiazol-2-Yl)-2,5-Diphenyltetrazolium Bromide (MTT) assay. Moreover, clonogenic assay was used for the estimation of effect of AT extract on colony forming ability of SCC9 cells.Result: Result of the study suggested that treatment with AT extract causes cytotoxicity to SCC9 cancerous cells. In addition, AT extract treatment reduces clonogenic potential of SCC9 cell and it also inhibits the proliferation of cell significantly (p<0.001) in G2/M phase.Conclusion: Thus, given study concludes that AT extract effectively attenuates the growth of SCC-9 cancerous cells by the virtue of its cytotoxic and anti clonogenic activity.Keywords: Aster tataricus, 3-(4, 5-Dimethylthiazol-2-Yl)-2,5-Diphenyltetrazolium Bromide (MTT) assay, Human oral squamous carcinoma, SCC-