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Abstract-The paper tries to show the positive effects of cooperative language learning on foreign langue learning and teaching. Compared with traditional language teaching, cooperative language learning conforms to the developmental trend of language teaching method and possesses considerable advantages. In the foreign language learning classrooms, cooperative language learning provides students with the necessary academic and social skills. The paper reveals cooperative learning benefits language learning in many aspects.

Phosphorus in water eutrophication has become a serious problem threatening the environment. However, the development of efficient adsorbents for phosphate removal from water is lagging. In this work, we recovered the waste material, graphitized carbon, from spent lithium ion batteries and modified it with nanostructured Mg(OH)2 on the surface to treat excess phosphate. This phosphate adsorbent shows one of the highest phosphate adsorption capacities to date, 588.4 mg/g (1 order of magnitude higher than previously reported carbon-based adsorbents), and exhibits decent stability. A heterogeneous multilayer adsorption mechanism was proposed on the basis of multiple adsorption results. This highly efficient adsorbent from spent Li-ion batteries displays great potential to be utilized in industry, and the mechanism study paved a way for further design of the adsorbent for phosphate adsorption.

In preclinical and phase I and II clinical studies, 2′-deoxy-2′-β-fluoro-4′-azidocytidine (FNC) displays a potent and long-lasting inhibition of HIV-1 infection. To investigate its mechanism of action, we compared it with the well-documented lamivudine (3TC). Pharmacokinetic studies revealed that the intracellular retention of FNC triphosphate in peripheral blood mononuclear cells was markedly longer than that of the 3TC triphosphate. FNC selectively enters and is retained in HIV target cells, where it exerts long-lasting prevention of HIV-1 infection. In addition to inhibition of HIV-1 reverse transcription, FNC also restores A3G expression in CD4+ T cells in FNC-treated HIV-1 patients. FNC binds to the Vif-E3 ubiquitin ligase complex, enabling A3G to avoid Vif-induced ubiquitination and degradation. These data reveal the mechanisms underlying the superior anti-HIV potency and long-lasting action of FNC. Our results also suggest a potential clinical application of FNC as a long-lasting pre-exposure prophylactic agent capable of preventing HIV infection.

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This article presents a research study on the deposition process of Ca 2C induced by Synechocystis sp. PCC6803 in BG11 liquid medium with different Ca 2C concentrations and different pH. The changes of Ca 2C concentrations were measured by using atomic absorption method and the corresponding dynamical models were studied. Minerals and cells were analyzed by high resolution transmission electron microscope, selected area electron diffraction, scanning electron microscope, energy dispersive X-ray spectroscope, X-ray diffraction. The selected area electron diffraction patterns were analyzed by Digital Micrograph 3.7 software. The result showed that Ca 2C concentrations decreased faster in the experimental group. The changes of calcium carbonate precipitation were fitting to an exponential model. PH 7 and Ca 2C concentration of 1.5 g/L were most conducive to calcium carbonate precipitation in the corresponding gradient range. The result of high-resolution transmission electron microscopy showed that minerals in the experimental group differed obviously from that of the control group in the surface morphology, but both of them were calcites. It also showed that a certain number of minute calcites adhesion to the outer surfaces of S. PCC6803 cells. The result of scanning electron microscopy displayed that many sunken holes emerged on the surfaces of the prismatic calcium carbonate minerals. The results of X-ray diffraction proved that minerals induced by S. PCC6803 were calcites with preferential orientation. This article discusses the process of carbonate formation and the possible role played by S. PCC6803. It may be useful to further study the mechanism of microbial carbonates deposition in the field of geology.

This work provides a simple and convenient method to manufacture the sorbent of Al-eggshell. The influence of AlCl 3 concentration and pH values as well as the dosage of sorbent and their interactions on adsorption of phosphate was investigated. Therefore, Box-Behnken design coupled with response surface method was adopted to explore the empirical model for phosphate species removal. It was observed that there is an optimal point, C(AlCl 3 )(0.29 mol/l)-pH(6.12)-dosage(6.72 g/l), for the goal of maximizing phosphate species removal. The second-order polynomial model for phosphate reduction was given asContour pictures implied that the interaction between pH values and sorbent dosage was the strongest, followed by C(AlCl 3 ) versus dosage and C(AlCl 3 ) versus pH. The adsorption of phosphate data had a good agreement with the Freundlich isotherm equation at 313 and 323 K. Otherwise, Langmuir-Freundlich model described the best fitness at the temperature of 293, 298, and 303 K. The process of adsorption of phosphate on Al-eggshell fitted a pseudo-second-order kinetic equation, which indicates the exothermic reaction. In conclusion, the present work suggests Al-eggshell as an efficient and environmental friendly sorbent for phosphate species adsorption from aqueous solutions.