Zhongda Liu

Background: Post-tuberculosis lung disease (PTLD) constitutes a substantial global public health burden, yet its overall research landscape has not been systematically quantified. This bibliometric study characterizes global research trends and the knowledge architecture of PTLD publications issued between 2015 and 2025. Methods: We retrieved PTLD-related literature from the Web of Science Core Collection using search terms including “post-tuberculosis lung disease” and “tuberculosis sequelae”. Only English original articles were retained, yielding a final dataset of 353 publications. We adopted VOSviewer, CiteSpace and the Bibliometrix R package to visualize annual publication outputs, cross-country and institutional collaborations, author co-authorship networks, keyword co-occurrence patterns, and citation burst dynamics. Results: Annual publications rose from 13 in 2015 to 67 in 2025, with 71.4% of all papers published from 2021 to 2025. The five most productive nations were the United States (72 papers), India (61), China (51), the United Kingdom (49), and South Africa (38). The US and UK occupied core hub positions in international collaboration networks. Leading institutions included Stellenbosch University (20 articles), the University of Cape Town (14), and the University of Liverpool/Liverpool School of Tropical Medicine (10). Keyword co-occurrence clustering identified eight thematic groups, with dominant hotspots covering post-tuberculosis bronchiectasis, pulmonary function impairment, chronic pulmonary aspergillosis (CPA), and quality of life. The keywords with the strongest recent citation bursts were “post-tuberculosis lung disease” (strength = 3.79), “prevalence” (3.70), and “quality of life” (2.51). Research frontiers extending to 2025 center on standardized PTLD conceptual framing, pulmonary rehabilitation, and long-term clinical outcome assessment. Conclusions: PTLD research has shifted from merely describing structural lung damage toward standardized disease definitions, functional pulmonary testing, complication management, and patient quality-of-life improvement. Future research priorities should include prospective multicenter cohort studies, individualized pulmonary rehabilitation programs, and host-directed therapies to mitigate the global burden of chronic PTLD.

To assess the performance, durability, and field applicability of soybean-oil-based dust suppressants, controlled laboratory experiments and a 3-week field particulate emissions monitoring program were conducted on unpaved roads. The laboratory program simulated wind erosion, wetting–drying durability, and traffic-induced loading. Soybean-oil treatments exhibited minimal mass loss and maintained surface integrity under all conditions, whereas calcium chloride brine (CCB) experienced substantial erosion. Field experiments were conducted on six sections treated with different materials, dosages, and application methods. Continuous on-vehicle monitoring and blower-induced particulate matter (PM) measurements showed that soybean oil applied at 0.8 L/m ² produced the lowest particulate emissions, and sustained strong performance throughout the 3 weeks. In contrast, the CCB-treated section exhibited rapidly increasing emissions. The area under the curve for particulate matter with aerodynamic diameters less than 2.5 µm (PM _2.5 ) increased by a factor of 11.59, indicating rapid performance degradation and the need for frequent reapplication. Cost analysis showed that soybean oil has a higher unit price than CCB; however the dosage flexibility provides cost advantages. A low-dosage application of 0.12 L/m ² costs 1.34 times the price of CCB yet demonstrates superior durability. Overall, soybean-oil-based dust suppressants offer advantages in performance, durability, and environmental profile. They also provide flexibility in balancing cost and treatment effectiveness. Future work incorporating life-cycle assessment and life-cycle cost analysis is needed to evaluate long-term environmental effects, reapplication intervals, and system-level cost effectiveness.

The incorporation of crumb rubber derived from waste tires in asphalt pavements has gained increasing attention as a strategy to enhance performance while reducing environmental impacts, particularly in cold regions such as the Midwestern United States, where pavements are subjected to severe thermal stresses and freeze–thaw cycles. Despite the numerous performance benefits observed in previous laboratory-scale studies, field demonstrations can play a critical role in validating the use of recycled waste tires as asphalt additives. This study examines the performance benefits and environmental impacts of incorporating recycled tire rubber into asphalt mixtures via a dry modification process for cold-climate applications. Building on these findings, this paper is based on a full-scale field demonstration of a dry-process rubber-modified asphalt pavement constructed in Ann Arbor, Michigan. Performance testing was conducted at both the binder and mixture levels, and field cores were collected during the construction of field sections. To complement the performance evaluation, a life-cycle assessment (LCA) was conducted to quantify the environmental impacts of rubber-modified asphalt and conventional asphalt. The results indicate that successful rubber incorporation, combined with improved low-, intermediate-, and high-temperature performance, enhances long-term durability compared with control sections. Moreover, despite slightly higher initial environmental impacts associated with rubber incorporation, improved durability and reduced maintenance frequency can lead to lower life-cycle impacts over the long term. The findings highlight the potential of rubber-modified asphalt as a sustainable, resilient solution for cold-region pavements, offering practical insights for agencies seeking to balance performance and environmental impacts in future infrastructure design.

This study investigated the feasibility and performance of using soybean oil as a bio-based recycling agent in recycled asphalt pavement (RAP) for road reconstruction in cold regions. A comprehensive demonstration project was conducted on a 5-mile section of Old State Road in Clare County, Michigan, where a 100% RAP mixture modified with soybean oil was produced and placed using a conventional asphalt paver equipped with a screed. Laboratory evaluations included balanced mix design, rutting and cracking testing, and binder performance analysis. Field application processes, including mixing and compaction, were also documented and evaluated. The asphalt mixture tests included the Hamburg wheel-tracking test (HWTT) and the indirect tensile asphalt cracking test (IDEAL-CT), while the asphalt binder tests included dynamic shear rheometer (DSR), asphalt binder cracking device (ABCD), rotational viscometer (RV), linear amplitude sweep (LAS), Fourier transform infrared spectroscopy (FTIR), and CO ₂ emission analysis. An optimal soybean oil dosage of 1.0 wt.% (based on the total weight of the mix) significantly improved low-temperature cracking resistance and fatigue life while maintaining rutting resistance. Results showed that soybean oil improved compaction performance and exhibited a cracking temperature approximately 3.3°C lower than that of untreated RAP based on the ABCD test. Fatigue performance was also enhanced. Fourier transform infrared spectroscopy (FTIR) analysis confirmed the chemical compatibility and interaction between soybean oil and the RAP binder. On-site application was completed smoothly without workability issues, and the final pavement met all compaction and density requirements. In summary, using soybean oil as an RAP recycling agent provides a practical and environmentally friendly solution to improve the performance of recycled asphalt mixes, especially for low-volume roads in cold climates, while supporting the sustainability of Michigan’s pavement and the growth of the soybean market.

This paper presents a comprehensive review of the environmentally friendly management and reutilization of electronic waste (e-waste) plastics in flexible pavement construction. The discussion begins with an overview of e-waste management challenges and outlines key recycling approaches for converting plastic waste into asphalt-compatible materials. This review then discusses the types of e-waste plastics used for asphalt modification, their incorporation methods, and compatibility challenges. Physical and chemical treatment techniques, including the use of free radical initiators, are then explored for improving dispersion and performance. Additionally, in situations where advanced pretreatment methods are not applicable due to cost, safety, or technical constraints, the application of alternative approaches, such as the use of low-cost complementary additives, is discussed as a practical solution to enhance compatibility and performance. Finally, the influence of e-waste plastics on the conventional and rheological properties of asphalt binders, as well as the performance of asphalt mixtures, is also evaluated. Findings indicate that e-waste plastics, when combined with appropriate pretreatment methods and complementary additives, can enhance workability, cold-weather cracking resistance, high-temperature anti-rutting performance, and resistance against moisture-induced damage while also offering environmental and economic benefits. This review highlights the potential of e-waste plastics as sustainable asphalt modifiers and provides insights across the full utilization pathway, from recovery to in-field performance.