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This study employed the technological pedagogical content knowledge (TPACK) framework to guide the collaborative design process between preservice and practicing teachers. The teams designed technological pedagogical mathematics tools (TPMTs) for inquiry-based learning based on the syllabi for secondary mathematics. The content of the chat messages of preservice and practicing teachers was coded with different dimensions of TPACK to unpack the process of how the teams arrived at critical design decisions. The TPMTs were further evaluated by 30 practicing mathematics teachers, with respect to three criteria: (1) technology tools and curriculum goals, (2) technology tools and teaching activities, and (3) the fit between pedagogy and technology. The content analysis revealed that the collaborative design process involved three clear stages, demarcated by the different versions of the TMPTs: replacement, enhancement, and transformation. Practicing teachers' pedagogical content knowledge played a crucial role in the design of pedagogically sound tools, and for refining the initial TPACK of preservice teachers. The subsequent evaluations supported the positive pedagogical values of the TPMTs. Overall, this study contributes to TPACK research with a case where the collaborative design process with distributed expert knowledge can be synthesised to create pedagogically sound technological tools for mathematics.

t-BuOK-mediatedrearrangement of 1,3-ketoesterswith 2-(azidomethyl) aromatics in a two-step, one-pot telescoped sequenceaffords β-enaminoketoesters in moderate to good yields. A novelpathway is proposed in which the umpolung of the azide is achievedfrom electrophilicity to nucleophilicity via deprotonation and undergoesnucleophilic attack onto the 1,3-ketoester. [ABSTRACT FROM AUTHOR]

The enantioselective synthesis of (-)-pavidolide B (1) was achieved in a linear sequence of 10 steps. The key steps are (a) an enantioselective organocatalytic cyclopropanation; (b) a radical-based cascade annulation for the regio- and diastereo-selective synthesis of the highly functionalized lactone 3 bearing the characteristic tricyclic core and seven contiguous stereocenters;, ((c) a sequential ring-closing metathesis reaction and a RhCl-catalyzed double bond isomerization to form the seven-membered D ring of (-)-pavidolide B.)

Objective: To explore a rapid and cost-effective method for identification of Candida glabrata through the comparison of two different methods, using molecular methods of sequencing as gold standard., Methods: From our clinic, 200 strains of suspected Candida glabrata were collected during the last 3 years and selected after incubation in CHROMagar Candida medium for 48 h. By comparing the results of the CHROMagar Candida medium, the identification of the rapid trehalose test for different kinds of strains were analyzed under incubation in the tubes for 3 h, 6 h, and 24 h at 37 °C and 42 °C, respectively. All the strains were identified to species level by methods of sequencing. The optimal time and temperature of the trehalose test for the identification of Candida glabrata were assessed. Two different methods, CHROMagar Candida medium and the rapid trehalose test, in identification of Candida glabrata were compared., Results: In all the 200 strains, Candida glabrata ferment trehalose with 3 h incubation under 42 °C were the optimal time and temperature for fermenting trehalose. The accuracy, sensitivity, and specificity of the rapid trehalose test were 99.00% (198/200), 98.66% (147/149) and 100.00% (51/51). The accuracy rate of CHROMagar Candida medium was 79.50% (159/200), the sensitivity and specificity were only 89.93% (134/149) and 49.02% (25/51), however, compared with the domestic current popular methods, the rapid trehalose test had better time efficiency ratio., Conclusion: The evaluation results suggest that the rapid trehalose test has advantages in terms of operational convenience and low cost, and the results can be obtained in 3 h. Therefore, it has application value in clinical laboratory.