Search Results (7)

The Wanning Bridge is a critical component of Beijing’s Central Axis World Heritage site and the only Yuan Dynasty heritage bridge in Beijing still in service. Investigating its structural response under complex traffic conditions is therefore essential for ensuring the longevity of this ancient structure and the safety of the urban transport system. However, the application of traditional research methods, such as direct sampling, is often constrained by the cultural relic characteristics of heritage bridges. This study first conducted a macroscopic on-site survey to document its current appearance and global geometry. Subsequently, more accurate geometric and material parameters of the bridge were acquired through non-destructive testing techniques including 3D laser scanning, ground-penetrating radar, and ultrasonic testing. Subsequently, using a combined approach of experimental and numerical simulation, this study reveals key structural responses and damage conditions of the bridge through static, dynamic, and metro-induced vibration tests. Dynamic tests show a maximum deformation of 0.26 mm and a natural frequency of 10.547 Hz, indicating shear strain accumulation as the primary damage driver. Subway-induced vibrations are well within the safety limits for stone relics, and the structure’s current load-bearing capacity complies with Class-II highway standards. Full article

Background: Primary healthcare (PHC) at the community level is essential to improving access to health services and reducing healthcare costs. However, compared to developed countries where PHC is well developed, PHC in developing countries is not as well developed. The worldwide prevalence of COVID-19 has put a tremendous strain on the healthcare systems of all countries. Interestingly, we found that the impact of COVID-19 on the global healthcare system has brought about a new opportunity for PHC in developing countries. Methods: Based on community-scale panel data from Beijing, China, in the period from 1 January 2018 to 30 June 2021, this paper employed the Anderson model to reveal the impact of COVID-19 on community health service utilization. Two-way fixed effects models and double-difference models were used to analyze the data for robustness. Results: The results show that COVID-19 significantly reduced visits to the Community Health Center, but meanwhile, it raised the cost of single visits. While the costs of treatment, together with medical materials, were significantly lower during the pandemic, COVID-19 has affected the cost control of family physicians, resulting in the cost of contracted patients being significantly lower than that of non-contracted patients. Conclusions: While the COVID-19 pandemic significantly reduced routine visits to established medical centers, it served as a catalyst for the increased utilization of community health services. If appropriate measures to contain COVID-19 were taken, it would be possible to extend the scope of community health services and strengthen the PHC system. Full article

Coding and non-coding RNAs (ncRNAs) are potential novel markers that can be exploited for TB diagnostics in the fight against Mycobacterium tuberculosis. The current study investigated the mechanisms of transcript regulation and ncRNA signatures through Total RNA Seq and small (smRNA) RNA Seq followed by Bioinformatics analysis in Beijing and F15/LAM4/KZN (KZN) clinical strains compared to the laboratory strain. Total RNA Seq revealed differential regulation of RNA transcripts in Beijing (n = 1095) and KZN (n = 856) strains compared to the laboratory H37Rv strain. The KZN vs. H37Rv coding transcripts uniquely enriched fatty acids, steroid degradation, fructose, and mannose metabolism as well as a bacterial secretion system. In contrast, Tuberculosis and biosynthesis of siderophores KEGG pathways were enriched by the Beijing vs. H37Rv-specific transcripts. Novel sense and antisense ncRNAs, as well as the expression of these transcripts, were observed, and these targeted RNA transcripts are involved in cell wall synthesis and bacterial metabolism in a strain-specific manner. RNA transcripts identified in the current study offer insights into gene regulation of transcripts involved in the growth and metabolism of the clinically relevant KZN and Beijing strains compared to the laboratory H37Rv strain and thus can be exploited in the fight against Tuberculosis. Full article

Objectives: In this study, we aimed to evaluate the non-inferiority of a quadrivalent influenza vaccine (QIV) developed by Sinovac Biotech Co., Ltd. (Sinovac, Beijing, China) by comparing its immunogenicity and safety with a comparator QIV (Vaxigrip Tetra^®) in a population aged 3 years and older in Chile and the Philippines. Methods: A phase 3, non-inferiority, double-blind, randomized controlled, multicenter clinical trial was conducted in the southern hemisphere (SH) 2023 influenza season. Participants aged ≥ 3 years old with stable health were randomized 1:1 to receive either Sinovac QIV or comparator QIV. The co-primary outcomes were immunological non-inferiority for Sinovac QIV versus the comparator against each strain contained in the vaccines in terms of seroconversion rates (SCRs) and geometric mean titers (GMTs) of hemagglutination inhibition (HI) antibodies 28 days after final vaccination. Results: A total of 2039 participants were vaccinated (1019 Sinovac QIV; 1020 comparator QIV). Sinovac QIV induced non-inferior immune responses to all four strains as compared to comparator QIV, with slightly higher GMTs than those of comparator QIV: GMT ratios (lower limit 95% confidence interval (CI)) were 1.8 (1.6) for A(H1N1), 1.4 (1.3) for A (H3N2), 1.3 (1.1) for B Victoria and 1.2 (1.1) for B Yamagata; observed seroconversion rate differences (lower limit 95% CI) were 9.6% (6.7) for A(H1N1), 7.0% (3.5) for A(H3N2), 2.4% (−0.03) for B Victoria and 6.8% (3.0) for B Yamagata. Adverse reactions were similar across the two groups and no vaccine-related serious adverse events were reported. Conclusions: The immunogenicity of Sinovac QIV was non-inferior to that of the comparator QIV in these populations aged 3 years and older, and safety was comparable. Full article

The advent of dockless bike-sharing (DBS) represents an effective solution to enhance public transportation usage. However, despite growing interest in integrating DBS with metro systems, comprehensive studies on their competitive and cooperative relationships remain limited. This study aims to analyze the spatial, temporal, and mobility characteristics of metro-related DBS to explore integration opportunities. Initially, three modes of interaction between DBS and metros are identified: strong competition, weak competition, and feeder relationships. Subsequently, based on these relationships, the analysis focuses on distance, spatio-temporal patterns, and the scope of DBS activities. Results from Beijing indicate that metro-associated DBS primarily serves as “last-mile” solutions without significant short-range competition with metro systems. Strongly competitive relationships, on the other hand, are interaction patterns due to the dense overlay of metro stations and inconvenient transfer facilities and are mainly used for non-commuting purposes. Furthermore, weakly competing and feeder DBS systems exhibit similar commuting patterns, highlighting bicycling as a viable alternative to walking within metro catchment areas and that metro catchment areas should be adapted to bicycling. Mobility communities, identified as tightly integrated cycling hubs, are proposed as strategic dispatch zones to manage peak demands and reduce operational strain on DBS fleets. These findings deepen our understanding of DBS and metro system interactions, offering insights to optimize public transport operations and enhance urban mobility solutions. Full article

The large population movement during the Spring Festival travel in China can considerably accelerate the spread of epidemics, especially after the relaxation of strict control measures against COVID-19. This study aims to assess the impact of population migration in Spring Festival holiday on epidemic spread under different scenarios. Using inter-city population movement data, we construct the population flow network during the non-holiday time as well as the Spring Festival holiday. We build a large-scale metapopulation model to simulate the epidemic spread among 371 Chinese cities. We analyze the impact of Spring Festival travel on the peak timing and peak magnitude nationally and in each city. Assuming an R₀ (basic reproduction number) of 15 and the initial conditions as the reported COVID-19 infections on 17 December 2022, model simulations indicate that the Spring Festival travel can substantially increase the national peak magnitude of infection. The infection peaks arrive at most cities 1–4 days earlier as compared to those of the non-holiday time. While peak infections in certain large cities, such as Beijing and Shanghai, are decreased due to the massive migration of people to smaller cities during the pre-Spring Festival period, peak infections increase significantly in small- or medium-sized cities. For a less transmissible disease (R₀ = 5), infection peaks in large cities are delayed until after the Spring Festival. Small- or medium-sized cities may experience a larger infection due to the large-scale population migration from metropolitan areas. The increased disease burden may impose considerable strain on the healthcare systems in these resource-limited areas. For a less transmissible disease, particular attention needs to be paid to outbreaks in large cities when people resume work after holidays. Full article

Objective: The Beijing strain of Mycobacterium tuberculosis (MTB) is controversially presented as the predominant genotype and is more drug resistant to rifampicin and isoniazid compared to the non-Beijing strain. We aimed to compare the major gene mutations related to rifampicin and isoniazid drug resistance between Beijing and non-Beijing genotypes, and to extract the best evidence using the evidence-based methods for improving the service of TB control programs based on genetics of MTB. Method: Literature was searched in Google Scholar, PubMed and CNKI Database. Data analysis was conducted in R software. The conventional and Bayesian random-effects models were employed for meta-analysis, combining the examinations of publication bias and sensitivity. Results: Of the 8785 strains in the pooled studies, 5225 were identified as Beijing strains and 3560 as non-Beijing strains. The maximum and minimum strain sizes were 876 and 55, respectively. The mutations prevalence of rpoB, katG, inhA and oxyR-ahpC in Beijing strains was 52.40% (2738/5225), 57.88% (2781/4805), 12.75% (454/3562) and 6.26% (108/1724), respectively, and that in non-Beijing strains was 26.12% (930/3560), 28.65% (834/2911), 10.67% (157/1472) and 7.21% (33/458), separately. The pooled posterior value of OR for the mutations of rpoB was 2.72 ((95% confidence interval (CI): 1.90, 3.94) times higher in Beijing than in non-Beijing strains. That value for katG was 3.22 (95% CI: 2.12, 4.90) times. The estimate for inhA was 1.41 (95% CI: 0.97, 2.08) times higher in the non-Beijing than in Beijing strains. That for oxyR-ahpC was 1.46 (95% CI: 0.87, 2.48) times. The principal patterns of the variants for the mutations of the four genes were rpoB S531L, katG S315T, inhA-15C > T and oxyR-ahpC intergenic region. Conclusion: The mutations in rpoB and katG genes in Beijing are significantly more common than that in non-Beijing strains of MTB. We do not have sufficient evidence to support that the prevalence of mutations of inhA and oxyR-ahpC is higher in non-Beijing than in Beijing strains, which provides a reference basis for clinical medication selection. Full article