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Rough set theory is a mathematical tool for dealing with uncertain information.The core notions of rough set theory is approximation operators of approximation spaces.Pawlak approximation operators are established by using equivalence relations on the universe.They are extended to generalized rough approximation operators based on arbitrary binary relations.The topolo-gical structures of approximation operators are important topics in rough set theory.This paper is devoted to the study of topological properties of generalized rough approximation operators induced by arbitrary binary relations.Four types of topologies induced by generalized approximation operators based on granules and subsystems are presented and the relationships among these four types of topologies are discussed.The bases of the topologies induced by generalized approximation operators based on granules are presented by the right-neighborhood systems for objects,and the normality and regularity for related topologies are investigated.By analyzing the properties of the generalized upper approximation operators based on the subsystem,it is proved that the topologies induced by the subsystem-based generalized upper approximation operators can be transformed into the topologies induced by the generalized lower approximation operators based on the objects.

Abstract Background To assess the role of Thymidine Phosphorylase and β-tubulin III in clinical outcome of Chinese advanced gastric cancer patients receiving first-line capecitabine plus paclitaxel. Methods The clinical data and tumor biopsies prior treatment from 33 advanced gastric cancer patients receiving capecitabine plus paclitaxel (cohort 1, experimental group) and 18 patients receiving capecitabine plus cisplatin (cohort 2, control group) in Beijing Cancer Hospital from July 2003 to December 2008 were retrospectively collected and analyzed for Thymidine Phosphorylase and β-tubulin III expressions by immunohistochemistry. The relationships between expressions of biomarkers and response or survival were determined by statistical analysis. Results The median age of 51 patients was 57 years (range, 27-75) with male 34 and female 17, and the response rate, median progression-free survival and overall survival were 43.1%, 120d and 265d. Among cohort 1, the response rate, median progression-free survival and overall survival in β-tubulin III positive (n = 22) and negative patients (n = 11) were 36.4%/72.7% (positive vs negative, P = 0.049), 86d/237d (P = 0.046) and 201d/388d (P = 0.029), respectively; the response rate (87.5% vs 14.3%, P = 0.01) and median progression-free survival (251d vs 84d, P = 0.003) in Thymidine Phosphorylase positive & β-tubulin III negative patients (n = 8) were also significantly higher than those in Thymidine Phosphorylase negative & β-tubulin III positive patients (n = 7). There was no correlation between β-tubulin III expression and response or survival among cohort 2 (n = 18). Conclusions In Chinese advanced gastric cancer, Thymidine Phosphorylase positive & β-tubulin III negative might predict response and prognosis to capecitabine plus paclitaxel chemotherapy. Further prospective evaluation in large samples should be performed to confirm these preliminary findings.

Objective To understand intake frequency of sugar-sweetened beverages (SSBs) and the consumption habit among primary and secondary students. To explore the relationship of SSBs cognition and behavior, and to provide a basis for reducing students' intake of SSBs. Methods A multi-stage sampling process was employed to select subjects from primary and middle school in Shenzhen. Network questionnaire survey was conducted to collecting information in September and October, 2021. Spearman rank correlations was used to analyze relationships of various types of SSBs consumption frequency. Multivariable linear regression model was used to examine the relationship between SSBs cognition score and consumption frequency score. Hierarchical analysis to explore the interactions. Results A total of 16 840 primary and secondary students aged 6 to 18 years old were included. The prevalence of SSBs consumption at least 3 time/week was 58.9%, the grades 1-3, 4-6 and middle school students were 52.3%, 60.3% and 67.6%. Parents (73.3%) were the main buyers of SSBs, convenience stores (73.7%) were the main places and delicious (77.2%) was the major cause of choices. There was a positive correlation between the intake frequency of different types of SSBs (P < 0.001). The results of multivariate linear regression showed that the higher the cognition was, the lower the intake frequency of SSBs was (β = 0.179, 95%CI: 0.155-0.204). There was a multiplicative interaction between the cognitive score of SSBs and the educational level of parents (P < 0.00l). Conclusion The intake frequency of SSBs was high among primary and middle school students in Shenzhen, and the cognitive level of SSBs was related to the intake frequency and the educational level of parents. [ABSTRACT FROM AUTHOR]

Recently, virtual and remote labs (VRLs) have been developed to support students in conducting experiments in engineering and science education. However, little is known about the students' intentions to continue using VRLs and their satisfaction with the experience. This study proposed an extended model embedded within the expectation confirmation model and two variables concerning flow experience (time distortion and focused attention) to predict Chinese university students' satisfaction with and intention to continue using VRLs. A structural equation modelling technique based on covariance was conducted to evaluate survey questionnaire responses received from 238 students at a university located in central China. The results demonstrated that satisfaction was the most crucial determinant of the students' intention to continue using VRLs, followed closely by perceived usefulness. Confirmation played an indirect role in predicting students' intentions to continue using VRLs via satisfaction and perceived usefulness. Students' flow experience while performing virtual experiments played a positive and direct role in confirming their expectations of VRLs. Implications for practice or policy: (1) Instructors and higher education institutions could improve students' satisfaction with VRL-based experimental teaching and increase their intention to continue using VRLs in their future studies by providing them with optimal flow experiences; (2) Designers and developers could improve the quality of these VRLs from the perspective of the users' flow experience; and (3) Researchers could verify more factors that influence confirmation and clarify how they could be manipulated in future studies.

Objective: To evaluate the image quality of brain MRI sequences accelerated by constellation shuttling imaging (uCS) to provide a basis for clinical application. Methods: Twenty volunteers underwent brain MRI scanning （TSE axial T1WI, T2-FLAIR, sagittal T1WI and GRE sagittal 3D-T1WI） twice using parallel imaging (routine scanning) and corresponding uCS accelerated acquisition. The evaluation of images in each sequence was conducted through combining the subjective (Likert five-point scale method, image artifact and overall quality) and objective (signal-to-noise ratio measurement) methods. Results: The scanning time of using uCS in each MRI sequence was shorter than that of conventional scanning. The total scanning time of uCS in each volunteer was 542 s, while that of conventional scanning was 735 s, which decreased 26.3%. The scanning time of 3D sequence was nearly reduced 39%. There is no statistically difference between uCS and conventional sequence in subjective evaluation (overall image quality and image artifact degree). The SNR of uCS axial T1WI and sagittal T1WI sequences was significantly higher than those of conventional axial T1WI and sagittal T1WI sequences(P