Constructed wetlands (CWs) primarily achieve efficient wastewater purification through synergistic interactions among substrates, plants, and microorganisms. Serving as the structural foundation of the entire wetland system, substrates not only provide a growth medium for plants, but also serve as adhesive carriers for microorganisms and habitats for animal activities. Research on substrates has attracted considerable attention; however, in practical engineering applications, the selection of substrates often depend on personal experience, which may lead to significant gaps in the effectiveness of wetland systems in treating different characteristic contaminants. Therefore, it is of great significance to investigate the influence of substrates on the removal of contaminants in sewage and identify substrate materials with good physical and chemical properties to optimize the design and operation of CWs-based sewage-treatment systems and improve their purification efficiency. In this review, bibliometric analysis was conducted to using the Web of Science database and VOSviewer_1.6.20 software to assess the progress of research on CWs. This article provides a comprehensive overview of substrate types and characteristics based on recent research advancements in the field. Additionally, it discusses removal methods and the influence of factors related to conventional contaminants (COD, nitrogen, and phosphorus), heavy metals (HMs), fluorinated compounds, pharmaceuticals, personal care products (PPCPs), and microplastics. A thorough evaluation was conducted on the economic costs of various substrates and their ability to remove major contaminants from water bodies, providing a reference for the further development of wetland technology.

Perfluorooctane sulfonate (PFOS) and perfluorooctanoic acid (PFOA) are a category of persistent, non-degradable pollutants that are widespread in the environment and in humans. They have attracted considerable attention due to their high bioaccumulation, multiple toxicities, long-term stability, and, in particular, their effects on human health. Therefore, there is an urgent need for highly efficient technologies and systematic mechanisms for the degradation of PFOS and PFOA. Therefore, we summarize four mainstream technologies for the degradation of PFOS and PFOA in water and their research progress in this review, namely adsorption, advanced oxidation processes, microbial treatment, and membrane separation. Among them, adsorption technology is the earliest and relatively mature, the advanced oxidation process has relatively high treatment efficiency, there are deep and broad development prospects for microbial treatment in the future, and membrane separation technology can recycle raw materials and help to save resources. Based on the analysis of the advantages and disadvantages of the existing technologies, the development prospect of reasonable optimization technology is prospected, with a view to providing a practical scientific reference for the research and engineering practice of PFOS and PFOA pollution control in China.

Introduction: The efficacy of root canal treatment is greatly impacted by a thorough understanding of root canal anatomy. This systematic review and meta-analysis aim to thoroughly investigate the root morphology and canal configuration (RMCC) of permanent premolars (PMs). Methodology: A comprehensive analysis was conducted following the PRISMA guidelines. Literature exploration was carried out across four electronic databases (PubMed, Embase, Cochrane, and Web of Science). The risk of bias assessment was conducted for the included studies utilizing the Anatomical Quality Assessment (AQUA) tool. Data analysis was performed utilizing SPSS and RevMAN5.3.3. The meta-analysis was applied with a 95% confidence interval to calculate odds ratios (OR). Results: Among the 82 selected studies, 59 studies exhibited potential bias in domain one (objective(s) and subject characteristics), followed by domain three (methodology characterization). The majority of maxillary PM1s had either single root (46.7%) or double roots (51.9%), while three-rooted variants were uncommon (1.4%). Conversely, most other PMs exhibited a single root. In terms of canal configuration, maxillary PM1s predominantly featured double distinct canals (87.2%), with the majority of maxillary PM2s displaying either a single canal (51.4%) or double canals (48.3%). Mandibular PMs were primarily characterized by single canals, accounting for 78.3% of mandibular PM1s and 90.3% of mandibular PM2s. Subgroup analyses revealed higher incidences of single-rooted and single-canalled PMs among Asians compared to Caucasians. Additionally, women exhibited a higher incidence of single-rooted PMs, while men showed a greater frequency of double-rooted PMs. Conclusions: The comprehensive analysis indicated that maxillary PM1s predominantly possess double roots and double canals, whereas maxillary PM2s and mandibular PMs were primarily characterized by single-rooted with a single canal. Notably, single root and single canal were more prevalent among women and Asian samples.