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With the rapid development of science and technology, knowledge update is accelerating, which puts forward higher requirements for teachers and students in Colleges and universities, and needs to grasp the latest development trends of curriculum knowledge related fields faster, more comprehensive and more accurate. Many schools have digitized their educational resources. However, the traditional sharing of educational resources lacks a unified knowledge representation structure, which makes the sharing and reuse of learning resources unsatisfactory. Curriculum is the core of school knowledge teaching. It evaluates the curriculum system and discipline system in order to achieve certain teaching objectives. Curriculum knowledge includes explicit knowledge and tacit knowledge.Knowledge map is a kind of model which can describe knowledge in semantic and knowledge level. Its purpose is to acquire, organize and present knowledge in a general and intuitive way, to search and match knowledge quickly, so as to improve the utilization of knowledge by learners and knowledge workers. Curriculum knowledge has obvious ontology characteristics, and there are many inconveniences and shortcomings in the presentation of traditional knowledge map. Using ontology technology to construct curriculum knowledge map can not only reflect the relationship between knowledge modules, but also realize the mining and representation of more knowledge relations and types such as tacit knowledge to a certain extent.

Background Gastric cancer presents a major health burden worldwide. Therefore, many molecular targeting agents have been evaluated for treatment of gastric cancer. Gefitinib has shown anticancer activity against gastric cancer which work through inhibiting epidermal growth factor receptor (EGFR). However, the effect of gefitinib is limited due to its resistance. Therefore, understanding the mechanisms of gefitinib resistance is desperately needed to formulate novel strategies against gastric cancer. Here, we analyzed resistance mechanism from the crosstalk between EGFR and integrin β4. Methods Integrin β4-expression vector or siRNA were used to analyze the functional effects of integrin β4 on chemoresistance of gastric cancer cells to gefitinib. EGFR and integrin β4 expression, proliferation and apoptosis of gastric cancer cells were assayed by indirect immunofluorescence, western blot, MTT and flow cytometry respectively. EGFR and integrin β4 expression were also assayed on patient samples. Results It was found that the integrin β4 expression was increased in gefitinib-resistant gastric cell line. The upregulated integrin β4 expression was identified to promote gefitinib resistance and proliferation, and inhibit apoptosis, while downregulation of integrin β4 was to inhibit gefitinib resistance and proliferation, and induce apoptosis. Moreover, the overexpression of integrin β4 in SGC7901 cells resulted in the down-regulation of p-EGFR protein levels while down-regulation of integrin β4, significantly resulted in overexpression of p-EGFR. The results of western blot from patients also showed there was obvious negative correlation between p-EGFR and integrin β4 in gastric cancer patients. Conclusion Considering the above results, it is concluded that the interaction of EGFR and integrin β4 may change the sensitivity of gefitinib treatment.

Coordination of supramolecular assemblies was investigated by reacting a series of lanthanide cations (Ln3+) with an inverted cucurbituril (iQ[6]) in the presence of tetrachloride zincate anion [ZnCl4]2−, as an structure directing agent in aqueous HCl (3.0 mol/L). Single crystal X-ray diffraction analysis revealed that the coordination of iQ[6] with Ln3+ gave rise to different interaction products and isomorphous groups with increasing atomic number. The interaction of iQ[6] with La3+ and Ce3+ immediately yielded precipitations and single crystal solids containing Pr3+ and Nd3+. No solids resulted from coordination of iQ[6] with Sm3+ and Eu3+, whereas single crystals solids were obtained from coordination of iQ[6] with heavy Ln3+, such as Gd3+, Tb3+, Dy3+, Ho3+, Er3+, Tm3+, Yb3+ and Lu3+. Such coordination characteristics may offer a strategy for isolating a series of Ln3+ cations in patches.

Single-molecule detection can reveal time trajectories and reaction pathways of individual intermediates/transition states in chemical reactions and biological processes, which is of fundamental importance to elucidate their intrinsic mechanisms. We present a reliable, label-free single-molecule approach that allows us to directly explore the dynamic process of basic chemical reactions at the single-event level by using stable graphene-molecule single-molecule junctions. These junctions are constructed by covalently connecting a single molecule with a 9-fluorenone center to nanogapped graphene electrodes. For the first time, real-time single-molecule electrical measurements unambiguously show reproducible large-amplitude two-level fluctuations that are highly dependent on solvent environments in a nucleophilic addition reaction of hydroxylamine to a carbonyl group. Both theoretical simulations and ensemble experiments prove that this observation originates from the reversible transition between the reactant and a new intermediate state within a time scale of a few microseconds. These investigations open up a new route that is able to be immediately applied to probe fast single-molecule physics or biophysics with high time resolution, making an important contribution to broad fields beyond reaction chemistry.

Coordination in supramolecular assemblies in aqueous HCl solutions was investigated by reacting alkaline-earth cations (AE2+) and inverted cucurbit[6]uril (iQ[6]) in the presence of the structure-directing agent, tetrachloride zincate ion. Single-crystal X-ray diffraction analysis revealed that the iQ[6]–Mg2+–[ZnCl4]2––HCl interaction system yielded a supramolecular assembly of iQ[6] and [ZnCl4]2– without forming coordination complexes of Mg2+ or Zn2+ with iQ[6]. In contrast, interaction of Ca2+ or Sr2+ with iQ[6] in the presence of [ZnCl4]2– gave rise to linear coordination polymers, which formed a honeycomb-like framework in which the linear polymers occupy cells of the framework. The iQ[6]–Ba2+–[ZnCl4]2––HCl interaction system immediately produced precipitates, thus preventing isolation of single crystals under similar synthetic conditions.

Dual-functional nanoparticles, with the property of aggregation-induced emission and the capability of reactive oxygen species, were used to achieve passive/active targeting of tumor. Good contrast in in vivo imaging and obvious therapeutic efficiency were realized with a low dose of AIE nanoparticles as well as a low power density of light, resulting in negligible side effects., Comment: 30 pages, 7 figures

Based on the analysis of the load curves taken from more than 300 beam pumping motors (BPMs) in China, a novel power-off control method for BPMs is developed, which enables the oil pumps to work continuously relying solely on the potential energy released during the power-off interval. The main advantages of this are: (1) variation of load curves is monitored by micro-computer in real time, and the control parameters, such as power-off moment and duration, are adjusted automatically; and (2) rapid soft re-switching technology, which is realized by SCR controlled by micro-computer, is developed for re-switching when the power source is needed during the power-off interval, by which the inrushing current is less than the rated one. To further broaden the applications for various beam pumping units, the multifunctional energy-saving device (MESD) is also developed, which uniquely integrates power-off control, wye-delta automatic conversion and auto-reactive power compensation technologies. During the past five years, more than 600 sets of MESDs had been put into use in Daqing oil field and the power saving ratio is in the range of 10-25%.

The spectra of volatiles of fresh garlic, Chinese chive and scallion plants were successfully recorded by headspace combined with surface-enhanced Raman scattering using the portable Raman spectrometer. For garlic: high intensity bands are present in 1622, 1397, 1287, 1182, 711, 569, 461 cm-1 and low intensity bands are present in 1017, 979, 918, 307 cm-1. For Chinese chives: the high intensity band is present in 672 cm-1 and low intensity bands are present in 1618, 1396, 1289, 1185, 575, 412, 274 cm-1 . For scallion high intensity bands are present in 699, 1023 cm-1 and low intensity bands are present in 369, 887, 1084, 1314 cm-1 . The main volatiles of fresh garlic, Chinese chive and scallion are diallyl disulfide, allyl methyl sulfide and 1-propanethiol respectively. As the bulk concentration changes, different conformers are absorbed on silver.

Two tomato (Lycopersicon esculentum) mutants with dark testae displaying poor germination rate and percentage on both water and 100 microM gibberellin(4 + 7) were recovered. The mutants were allelic (black seed1-1; bks1-1 and bks1-2), inherited in Mendelian fashion as a recessive gene residing on chromosome 11. They are not allelic to bs (brown seed) -1, -2, or -4, which impair seed germination and possess dark testae. The bks/bs mutants accumulated dark pigment in the cell layers of the testa above the endothelium, which itself accumulated proanthocyanidins similar to wild type. The poor germination performance of bks mutant seeds was because of impediment of the mutant testae to radicle egress. Imbibition on gibberellin(4 + 7) did not ameliorate germination percentage or rate. The toughening of the bks testa and associated poor germination were partially overcome when seeds were not dried before germination or were dried under N(2). The seeds of the bks mutant have elevated activity of at least one enzyme responsible for the detoxification of reactive oxygen species. The bks mutant is epistatic to 12 anthocyaninless mutants of tomato. Bio- and physicochemical analysis of the bks testa determined that it accumulated a melanic substance. Inheritance of bks/bs mutations contrasts with that of the anthocyaninless mutants, which are inherited according to the genotype of the maternally derived testa. This suggests that the testa manufactures components before its demise that can maximize testa strength, whereas the endosperm/embryo produces factors that are conveyed to the testa, mitigating this process.