Assessment of the supply/demand balance of medical resources in Beijing from the perspective of hierarchical diagnosis and treatment.

Considering the United Nations' Sustainable Development Goals (SDGs) and the need for a balanced spatial distribution of urban medical resources capable of perspective of hierarchical diagnosis and treatment, i.e. providing continuous and accessible medical services during potential public health emergencies, we assessed accessibility and service capacity of the three hospital levels in Beijing. Using geographical information systems (GIS) and the two-step floating catchment area method with the street as research unit, we found that there is an over-supply of medical resources in the centre of the city with weaker support in the peripheral areas as manifested by less supply in relation to popular demand of medical services. The spatial distribution of hospitals at all levels and their resources was found to be uneven: 82.4% of the residents can reach a tertiary hospital (a hospital offering advanced specialized medical and health services to multiple regions) within a 15-minute drive; 50.6% can reach a secondary hospital (a hospital offering comprehensive medical and health services to various communities) within a 10-minute drive; and 77.6% can reach a primary hospital (a hospital directly delivering prevention, medical treatment, healthcare, and rehabilitation services to the community of a certain population) within a 15- minute walk. It was noted that the supply/demand balance of medical resources in the tertiary hospitals decreases from the centre to the periphery, while the secondary hospitals show a dual-centre pattern and the primary hospitals a more uneven distribution, with oversupply in the East and the opposite in the Centre. The results of the study provide supplementary decision support for improving the hierarchical diagnosis and treatment system and accelerate the overall deployment of medical resources.

Online Video Anomaly Detection.

With the popularity of video surveillance technology, people are paying more and more attention to how to detect abnormal states or events in videos in time. Therefore, real-time, automatic and accurate detection of abnormal events has become the main goal of video-based surveillance systems. To achieve this goal, many researchers have conducted in-depth research on online video anomaly detection. This paper presents the background of the research in this field and briefly explains the research methods of offline video anomaly detection. Then, we sort out and classify the research methods of online video anomaly detection and expound on the basic ideas and characteristics of each method. In addition, we summarize the datasets commonly used in online video anomaly detection and compare and analyze the performance of the current mainstream algorithms according to the evaluation criteria of each dataset. Finally, we summarize the future trends in the field of online video anomaly detection.

Fabrication and characterization of lignin-xylan hybrid nanospheres as pesticide carriers with enzyme-mediated release property.

Lignin nanospheres (LNPs) are an emerging high-value material platform to realize lignin valorization. The modification or introduction of new functions to LNPs is of great significance to expand its downstream applications. This work evaluated the technical feasibility of preparing lignin-xylan hybrid nanospheres (LXNPs) through a simple solution-based self-assembly process, with the goal of achieving the application as pesticide carriers for enzyme-mediated controlled release. Hybrid LXNPs with various weigh ratios (lignin to xylan, 3 : 1, 1 : 1, 1 : 3) were obtained using deep eutectic solvent-extracted condensed lignin and water-insoluble xylan fragments, which exhibited a nanosphere size of about 166-210 nm with considerable stability in the pH range of 4-10. LXNPs with lignin to xylan ratios of 3 : 1 and 1 : 1 showed well-defined core-shell structures with enriched hydroxyl groups on the surface. It was proposed that lignin could anchor xylan fragments through van der Waals force and hydrophobic interactions between lignin phenylpropanes and xylan molecular backbones, thus facilitating the self-assembly process for the formation of this specific spherical structure. The resulting hydrophobic LXNPs core enabled the facile encapsulation of the biological pesticide avermectin (AVM) with 57.9-67.0% efficiency using one-pot synthesis. When these AVM-encapsulated LXNPs were subjected to enzymatic hydrolysis using xylanase, considerable AVM release of 44.8-55.1% was achieved after 16 h, in comparison to the 4.1% release only for those without xylanase. This work showed the high promise of fabricating hybrid LXNPs through the self-assembly process and also provided a universal nanosphere carrier for drug encapsulation and subsequent enzyme-mediated controlled release.

Fabrication of spherical lignin nanoparticles using acid-catalyzed condensed lignins.

Valorization of lignin by-products enhances the overall economics of current lignocellulose biorefinery. This work showed the high potential of fabricating acid-catalyzed condensed lignin fragments into high-value lignin nanoparticles (LNPs) with spherical structure. Four condensed lignins, i.e., liquid hot water pretreated hardwood aspen and eucalyptus lignin, steam pretreated softwood lodgepole pine and herbaceous corn stover lignin, were assessed for their abilities for LNPs using facile self-assembly method. Results showed the contents of condensed aromatics (0.20-0.67 mmol g-1) were varied with biomass species and hydrothermal pretreatment methods selected. Those resulting LNPs exhibited yields from 17.5 to 29.4%, particle sizes ranging from 20 to 100 nm and considerable suspension stabilities at pH 4-10. It was proposed that higher content of condensed lignin aromatics could provide more anchors available for their self-assembly through enhanced hydrophobic interactions, thus LNPs with more uniform particle size could be obtained. This work showed the technical opportunity to enhance the value of intractable condensed lignin through LNPs production towards a multi-product lignocellulose biorefinery.