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"Chen, Da"
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Changing profiles of cancer burden worldwide and in China: a secondary analysis of the global cancer statistics 2020
Cancer is one of the leading causes of death globally, but its burden is not uniform. GLOBOCAN 2020 has newly updated the estimates of cancer burden. This study summarizes the most recent changing profiles of cancer burden worldwide and in China and compares the cancer data of China with those of other regions.
We conducted a descriptive secondary analysis of the GLOBOCAN 2020 data. To depict the changing global profile of the leading cancer types in 2020 compared with 2018, we extracted the numbers of cases and deaths in 2018 from GLOBOCAN 2018. We also obtained cancer incidence and mortality from the 2015 National Cancer Registry Report in China when sorting the leading cancer types by new cases and deaths. For the leading cancer types according to sex in China, we summarized the estimated numbers of incidence and mortality, and calculated China's percentage of the global new cases and deaths.
Breast cancer displaced lung cancer to become the most leading diagnosed cancer worldwide in 2020. Lung, liver, stomach, breast, and colon cancers were the top five leading causes of cancer-related death, among which liver cancer changed from the third-highest cancer mortality in 2018 to the second-highest in 2020. China accounted for 24% of newly diagnosed cases and 30% of the cancer-related deaths worldwide in 2020. Among the 185 countries included in the database, China's age-standardized incidence rate (204.8 per 100,000) ranked 65th and the age-standardized mortality rate (129.4 per 100,000) ranked 13th. The two rates were above the global average. Lung cancer remained the most common cancer type and the leading cause of cancer death in China. However, breast cancer became the most frequent cancer type among women if the incidence was stratified by sex. Incidences of colorectal cancer and breast cancer increased rapidly. The leading causes of cancer death varied minimally in ranking from 2015 to 2020 in China. Gastrointestinal cancers, including stomach, colorectal, liver, and esophageal cancers, contributed to a massive burden of cancer for both sexes.
The burden of breast cancer is increasing globally. China is undergoing cancer transition with an increasing burden of lung cancer, gastrointestinal cancer, and breast cancers. The mortality rate of cancer in China is high. Comprehensive strategies are urgently needed to target China's changing profiles of the cancer burden.
Journal Article
Metasurface-integrated vertical cavity surface-emitting lasers for programmable directional lasing emissions
Vertical cavity surface-emitting lasers (VCSELs) have made indispensable contributions to the development of modern optoelectronic technologies. However, arbitrary beam shaping of VCSELs within a compact system has remained inaccessible until now. The emerging ultra-thin flat optical structures, namely metasurfaces, offer a powerful technique to manipulate electromagnetic fields with subwavelength spatial resolution. Here, we show that the monolithic integration of dielectric metasurfaces with VCSELs enables remarkable arbitrary control of the laser beam profiles, including self-collimation, Bessel and Vortex lasers, with high efficiency. Such wafer-level integration of metasurface through VCSEL-compatible technology simplifies the assembling process and preserves the high performance of the VCSELs. We envision that our approach can be implemented in various wide-field applications, such as optical fibre communications, laser printing, smartphones, optical sensing, face recognition, directional displays and ultra-compact light detection and ranging (LiDAR).Non-intrusive integration of metasurfaces with vertical cavity surface-emitting lasers enables fully arbitrary wavefront control for directional laser emission.
Journal Article
Antioxidant Activity of Quercetin and Its Glucosides from Propolis: A Theoretical Study
Among the multiple components of propolis, flavonoids contribute greatly to the antioxidant activities of propolis. Flavonoids mainly exist in the form of sugar-conjugated derivatives. Quercetin glycosides represent the predominant flavonoid fraction in propolis. In this work, density functional theory (DFT) calculations were applied to analyze the antioxidative properties of quercetin and its glucosides in the gas and in the liquid phase (ethanol, water). Three main antioxidant mechanisms, hydrogen atom transfer (HAT), single electron transfer followed by proton transfer (SET-PT) and sequential proton loss electron transfer (SPLET) were used to analyze the antioxidative capacity of the investigated compounds. Solvent effects dominantly affect SET-PT and SPLET. Thus, the thermodynamically preferred mechanism can be altered. HAT and SPLET are the thermodynamically dominant mechanisms in gas and solvent phases, respectively. Therefore, in the gas phase, the sequence of the antioxidative capacity is similar with the bond dissociation enthalpy values: quercetin > quercetin-5-
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-glucoside > quercetin-7-
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-glucoside > quercetin-3-
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-glucoside > quercetin-3′-
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-glucoside > quercetin-4′-
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-glucoside. While, in the solvent phases, the sequence is similar with the proton affinity values: quercetin-4′-
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-glucoside > quercetin-5-
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-glucoside > quercetin > quercetin-3-
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-glucoside > quercetin-7-
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-glucoside > quercetin-3′-
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-glucoside. OH groups in B-ring and C-ring contribute mainly to the antioxidative activities of quercetin and glucosides compared with A-ring.
Journal Article
Functional pavements : proceedings of the 6th Chinese-European Workshop on Functional Pavement Design (CEW 2020), Nanjing, China, 18-21 October 2020
\"Functional Pavements is a collection of papers presented at the 6th Chinese-European Workshop (CEW) on Functional Pavement Design (Nanjing, China, October 18-21, 2020). The focus of the CEW series is on field tests, laboratory test methods and advanced analysis techniques, and cover analysis, material development and production, experimental characterization, design and construction of pavements. The main areas covered by the book include: Asphalt binders for flexible pavements Asphalt mixture evaluation and performance Pavement construction and maintenance Pavement Surface Properties and Vehicle Interaction Cementitious materials for rigid pavements Pavement geotechnics and environment Functional Pavements aims at contributing to the establishment of a new generation of pavement design methodologies in which rational mechanics principles, advanced constitutive models and advanced material characterization techniques shall constitute the backbone of the design process. The book will be much of interest to professionals, academics and practitioners in pavement engineering and related disciplines as it should assist them in providing improved road pavement infrastructure to their stakeholders.\"-- Provided by publisher.
Book
Global and local path planning of robots combining ACO and dynamic window algorithm
As a key technology, robot path planning is of great significance in safely and efficiently completing tasks. However, faced with the challenges of static and dynamic obstacles in complex environments, traditional path planning methods have limitations in terms of efficiency and adaptability. Therefore, a global and local path planning method combining improved ant colony algorithm and improved dynamic window algorithm is proposed. The optimization ability, convergence efficiency, and obstacle avoidance performance are optimized in complex environments. The innovation is reflected in the proposed cone pheromone initialization, adaptive heuristic factor regulation, and ant colony division of labor strategies, which improve the global search ability and convergence speed of ant colony algorithm. In addition, the path direction angle evaluation function and dynamic velocity sampling optimization are introduced to enhance the obstacle avoidance stability of dynamic window algorithm. The research results showed that the optimization method had the greatest improvement on the basic ant colony algorithm, with an average path reduction of 30.18 and an accuracy increase of 98.46%. In a 20*20 grid map, the improved strategy achieved convergence in the 23rd iteration, with an average path length of only 25.87 during convergence. In a 30*30 grid map, the improved method converged in the 81st iteration, and the path length at convergence was 41.03. In the designed four environments, the smoothness was 0.94, 0.91, 0.79, and 0.65, all of which were better than comparison algorithms. The designed method based on improved dynamic window algorithm can effectively avoid dynamic obstacles. The research not only improves the efficiency and robustness of the path planning algorithm, but also improves the autonomous navigation ability of robots in complex environments, providing more adaptive path planning schemes for industrial automation, service robots, exploration robots and other fields.
Journal Article