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Selective activation of the C–H bond of aromatic hydrocarbons is significant in synthetic chemistry. However, achieving oriented C–H activation remains challenging due to the poor selectivity of aromatic C–H bonds. Herein, we successfully constructed alternately arranged Au–C4 and Au–O4 organometallic coordination networks through selective aromatic C–H bond activation on Au(111) substrate. The stepwise reaction process of the 5, 12-dibromopyrene 3,4,9, 10-tetracarboxylic dianhydride precursor is monitored by high-resolution scanning tunneling microscopy. Our results show that the gold atoms in C–Au–C organometallic chains play a crucial role in promoting the selective ortho C–H bonds activation and forming Au–C4 coordination structure, which is further demonstrated by a comparative experiment of PTCDA precursor on Au(111). Furthermore, our experiment of 2Br-PTCDA precursor on Cu(111) substrate confirms that copper atoms in C–Cu–C organometallic chains can also assist the formation of Cu–C4 coordination structure. Our results reveal the vital effect of organometallic coordination on selective C–H bond activation of reactants, which holds promising implications for controllable on-surface synthesis. [ABSTRACT FROM AUTHOR]

In view of the effective detection of highly toxic heavy metal chromium Cr (Ⅵ) ions in printing and dyeing wastewater is rather difficult, the Zr-metal organic framework (Zr-MOF) was synthesized by combining 2, 2′-bipyridine-5, 5′-dicarboxylic acid (H2L) under solvent thermal reaction. In addition, powder X-ray diffraction characterization demonstrated the high water stability of Zr-MOF, and fluorescence spectroscopy tests confirmed the photoluminescence properties of Zr-MOF. Moreover, the experimental results show that the synthesized Zr-MOF can be used for fluorescence quenching recognition and detection of Cr (Ⅵ) ions, and can resist the interference of a variety of mixed anions. The detection limits (Molar ratio) of Zr-MOF for Cr2O2-7 and CrO2-4 were 2.15×10-9 and 2.33×10-9, respectively. The mechanism by which Cr (Ⅵ) ions cause the fluorescence quenching response of Zr-MOF also was proposed.

Student evaluations of teaching have considerable impact on teaching improvement. However, there is no reliable instrument that can reflect nursing students' perspectives of teaching evaluations in China. To design a student-centred evaluation instrument of nursing teaching in China, we developed and psychometrically tested the Nursing Course Experience Questionnaire (NCEQ). A literature review, student focus group interviews, student group discussion, Delphi survey, and a pilot test were used to confirm the content of the questionnaire. The data from 581 nursing students were randomly divided into sample A (n = 283) for exploratory factor analysis and sample B (n = 298) for confirmatory factor analysis and questionnaire reliability assessment. The final version of the NCEQ included 31 items and 6 sub-scales. The Cronbach's [alpha] was 0.968 for the whole questionnaire and >0.751 for the sub-scales, which indicated that the NCEQ was an effective instrument that can be employed to evaluate nursing students' perspectives on teaching in China.

Background: Involvement of the recurrent laryngeal nerve (RLN) in papillary thyroid carcinoma (PTC) is an important prognostic factor and is associated with a higher risk of recurrence. This study aimed to retrospectively analyze the outcomes of patients treated with hemithyroidectomy (HT) in PTC patients with an exclusive RLN invasion who could not tolerate staged surgery, did not wish to undergo another operation, or had other reasons. Methods: A retrospective review was conducted on 163 patients with PTC and exclusive RLN involvement at our institution between 2013 and 2019. Patients were divided into a total thyroidectomy (TT) group and HT group. The clinicopathologic factors and prognostic outcomes were compared between the two groups. A propensity score-matched analysis was carried out to reduce selection bias, with the following covariates: gender, age, tumor size, multifocality, central lymph node metastasis (CLNM), and RLN resection. The Kaplan–Meier method was used for a comparison of recurrence outcomes. Results: In the baseline data of the 163 PTC patients, tumor size (p < 0.001), multifocality (p = 0.011), CLNM (p < 0.001), and RLN resection (p < 0.008) in the TT and HT groups differed significantly, whereas age and gender did not differ between the two groups. The TT group reported significantly higher temporary and permanent hypoparathyroidism than the HT group (p < 0.001 and p = 0.042, respectively). With 72-month median follow-up, 11 (6.7%) patients developed recurrence. After propensity score matching, 24 patients with HT and 43 patients with TT were included. Recurrence-free survival (RFS) in the matched samples showed no difference between the TT and HT groups (p = 0.092). Conclusion: Our results indicate that HT may be a feasible treatment for PTC patients with exclusive RLN involvement in specific circumstances without significantly increasing the risk of recurrence. Performing a thorough preoperative examination is crucial to exclude multifocal tumors and lymph node metastasis before undergoing HT. [ABSTRACT FROM AUTHOR]

Student evaluations of teaching have considerable impact on teaching improvement. However, there is no reliable instrument that can reflect nursing students' perspectives of teaching evaluations in China. To design a student-centred evaluation instrument of nursing teaching in China, we developed and psychometrically tested the Nursing Course Experience Questionnaire (NCEQ). A literature review, student focus group interviews, student group discussion, Delphi survey, and a pilot test were used to confirm the content of the questionnaire. The data from 581 nursing students were randomly divided into sample A (n = 283) for exploratory factor analysis and sample B (n = 298) for confirmatory factor analysis and questionnaire reliability assessment. The final version of the NCEQ included 31 items and 6 sub-scales. The Cronbach's α was 0.968 for the whole questionnaire and >0.751 for the sub-scales, which indicated that the NCEQ was an effective instrument that can be employed to evaluate nursing students' perspectives on teaching in China. [ABSTRACT FROM AUTHOR]