Cellular proliferation is a basic process during organ development, tissue homeostasis, and/or disease progression. Likewise, after injury typically multiple cell lineages respond to various cues and proliferate to initiate repair and/or remodeling of the injured tissue. Unravelling the specific role of proliferation of one cell type and its lineage in the context of the whole organism during tissue regeneration and/or disease progression would provide valuable information on these processes. Here we reported a new genetic system to inhibit cell proliferation in a tissue-specific manner. We generated Cre- or Dre-inducible p21-GFP (ip21-GFP) transgenic mice that allow for the experimentally-induced permanent cell cycle arrest of specific cell lineages of interest, while genetically marking these cells. This system allows for the inhibition of pathogenic cell proliferation. We found that cardiac fibroblast proliferation inhibition significantly reduced scar formation, and promoted neovascularization and cardiomyocyte survival. Additionally, we found that inhibition of one type of cell proliferation (namely, hepatocytes) induces the lineage conversion of another type cells (ie, ductal cells) during tissue regeneration. These results validate the use of ip21-GFP mice as a new genetic tool for cell lineage-specific inhibition of cell proliferation in vivo.

Air pollution is becoming increasingly serious along with social and economic development in the southwest of China. The distribution characteristics of particle matter (PM) were studied in Chengdu from 2016 to 2017, and the changes of PM bearing water-soluble ions and heavy metals and the distribution of secondary ions were analyzed during the haze episode. The results showed that at different pollution levels, heavy metals were more likely to be enriched in fine particles and may be used as a tracer of primary pollution sources. The water-soluble ions in PM_2.5 were mainly Sulfate-Nitrate-Ammonium (SNA) accounting for 43.02%, 24.23%, 23.50%, respectively. SO₄²⁻, NO₃⁻, NH₄⁺ in PM₁₀ accounted for 34.56%, 27.43%, 19.18%, respectively. It was mainly SO₄²⁻ in PM at Clean levels (PM_2.5 = 0~75 μg/m³, PM₁₀ = 0~150 μg/m³), and mainly NH₄⁺ and NO₃⁻ at Light-Medium levels (PM_2.5 = 75~150 μg/m³, PM₁₀ = 150~350 μg/m³). At Heavy levels (PM_2.5 = 150~250 μg/m³, PM₁₀ = 350~420 μg/m³), it is mainly SO₄²⁻ in PM_2.5, and mainly NH₄⁺ and NO₃⁻ in PM₁₀. The contribution of mobile sources to the formation of haze in the study area was significant. SNA had significant contributions to the PM during the haze episode, and more attention should be paid to them in order to improve air quality.

Mining activities have led to severe air pollution problems while they make great contributions to economic construction. Therefore, as a typical steel-industry city in southwest China, Panzhihua, its air pollution has received extensive attention. The characteristics of PM₁ in different functional areas of Panzhihua from 2018 to 2019, and the changes of its microstructure and potentially toxic elements (PTEs) and the sources of PM₁ were analyzed. The results showed that the mass concentrations of PM₁ in the heavy pollution area of Nongnongping (NNP) and the complex industrial pollution area of Hemenkou (HMK) were 12.12–145.30 μg/m³ and 14.38–67.02 μg/m³, respectively. Seasonal PM₁ mass concentrations in the two functional areas could be arranged in the following order: winter > autumn > spring > summer. The main particle types in PM₁ were fly ash, soot, sulphate particles, aluminosilicate particles and metal particles. Potential sources of PM₁ in Panzhihua included coal burning, biomass combustion, automobile exhaust and mining activities. At the same time, the average concentrations of PTEs at NNP were also higher than those at HMK because of smelting activities. Enrichment factor analysis showed that most of the PTEs came from human sources. The results could provide theoretical guidance for environmental management.

As the place where students live for the longest time, the levels, sources and health risks of heavy metals in road dust from university campuses have not been widely studied. In the present study, 41 road dust samples were collected and analyzed by ICP-MS for Zn, V, Pb, Cr, Ni and Cu. The isotopic composition of Pb was analyzed by MC-ICP MS. These heavy metals were specifically analyzed using enrichment factor, geoaccumulation index, principal component analysis, iso-sources model and health risk assessment model. Zn and Pb pollution levels were high in road dust, and they were defined as moderate enrichment and contaminated. The sources of Pb in road dust from university campus were traffic exhaust, steel smelting, soil, and fly ash, accounting for 59.4%, 23.2%, 12.2%, and 5.2%, respectively. The non-carcinogenic risk of female and male university students is safe, but the carcinogenic risk of Cr needs to be concerned by the authorities.

Thallium (Tl) contamination of soils in lead-zinc mining areas poses potential ecological risks, and the impact of microplastics on Tl accumulation by hyperaccumulator plants remains unclear. This study examined soils collected from the Daliangzi lead-zinc mining area to investigate the characteristics of Tl contamination. These soil samples were used in plant cultivation experiments. The thallium contents in both the soil and plant samples were determined using acid digestion followed by inductively coupled plasma mass spectrometry (ICP-MS). The contamination level, plant enrichment capacity, and ecological risk were then comprehensively evaluated through the Geo-accumulation index (I_geo), Bioconcentration factor (BCF), and potential ecological risk index. The results indicated that the I_geo of Tl in the soil was 2.413, corresponding to a moderately to heavily polluted level, which necessitates focused attention. Polyethylene exhibited markedly opposing effects on Pteris vittata and Solanum nigrum: it significantly promoted Tl accumulation in the former, while distinctly inhibiting it in the latter. Microplastics could modify the pH value of soil, as well as the contents of nitrogen (N) and phosphorus (P). Risk assessment indices indicated that Tl pollution in this region reaches a very high contamination level with moderate potential ecological risk. Polyethylene and polypropylene demonstrated a species-specific promoting effect on Tl adsorption by the two hyperaccumulator plants, with polyethylene significantly enhancing the Tl accumulation capacity of P. vittata and polypropylene distinctly promoting Tl adsorption in S. nigrum.

As a keystone species in alpine ecosystems, the Tibetan fox (Vulpes ferrilata) plays an important role in maintaining ecological processes on the Qinghai–Tibet Plateau. Understanding its behavioral structure, activity rhythm, and responses to road-related human disturbance is essential for effective conservation and management. This study was conducted in the Tangbei Area of Sanjiangyuan National Park from May to December 2024 using infrared camera trapping. In total, 1166 effective camera-trap days yielded 748 independent photographs, 340 video clips, and 217 valid behavioral records. An ethogram was constructed, and activity patterns and responses to human disturbance were analyzed. The results showed that: (1) Tibetan fox behavior was dominated by locomotion (55.18%), followed by vigilance (23.20%) and scent marking (17.68%). (2) The species exhibited pronounced nocturnality, with an overall daily activity rate of 76.20%. Activity peaked at night (22:00–04:00), reaching 92.63%, while the lowest activity level occurred around midday (12:00), with an activity rate of 44.63%. (3) Roads and human activities significantly altered the behavioral structure of Tibetan foxes. The study indicates that Tibetan foxes adapt to human disturbance through temporal allocation and spatial avoidance, which may affect its social structure and increase energy expenditure. In future conservation practices, focus should be placed on the management of human activities in the region, with enhanced efforts in the construction of ecological corridors, restoration of habitat connectivity, and control of traffic intensity. This study provides scientific evidence to support wildlife conservation and human activity management in alpine protected areas of the Qinghai–Tibet Plateau. The quantified behavioral baseline and disturbance response patterns also offer reference indicators for conservation veterinary medicine assessment and wild canid welfare monitoring, which can be used to evaluate the health status of Tibetan fox populations under anthropogenic pressure.