Particle removal by vegetation: comparison in a forest and a wetland

Vegetation collection is one of the most effective scavenging methods but relevant studies are limited. It can be described by some abstract parameters such as collection rates and deposition fluxes within the canopy. In order to estimate the dry deposition within the canopy of particular matters (PMs) in Beijing, a highly particle-polluted city, and reveal the PM pollution-removal abilities of plants in wetlands and forests, concentration and meteorological data were collected during the daytime in an artificial forest and a wetland in the Olympic Park in Beijing. The dry depositions within the canopy and vegetation collection rates were calculated by a well-developed model and validated by measured deposition fluxes in 11 random experiment days. The experiment year was divided into three plant growth stages based on canopy density, and the day was divided into four different times. Two heights, 10 and 1.5 m, were defined in the forest while in the wetland, 0.5 and 1.5 m were defined. The results showed that in Beijing, the most severe pollution by PMs occurs in the non-leaf stage (NS), and the full-leaf stage (FS) is the cleanest stage. In NS, namely winter, more fossil fuel was used for worms in Beijing and peripheral areas and this might be the reason for the serious pollution condition. Within the canopy, PM deposition fluxes in the wetland are more than those in the forest, but the vegetation collection rates of the forest are higher. The lower temperature conditions led to more dry deposition, and the larger canopy contributed to the higher collection rates. During the daytime, over the year, the deposition of PM₁₀ in three plant growth stages is NS ≥ half-leaf stages (HS) ≥ FS, whereas the deposition of PM_2.5 is NS ≥ FS ≥ HS, and during the daytime, the maximum deposition fluxes occur in 6:00-9:00 in the wetland while the minimum deposition values occur in 15:00-18:00. This phenomenon was related to the temporal variation of particle concentration.

Study on metabolic disorders in rat liver induced by different times after scalds

Previous studies have confirmed that burns and scalds can lead to metabolic disorders in the liver. However, the effects of severe burns at various time points on liver lipid metabolism disorders, as well as the relationship between these disorders and liver function, metabolism, and infection, have not yet been investigated.This study established a SD rat scald model, macroscopic observation of weight changes, histological staining, Western blot detection of fat browning and metabolic indicators, reverse transcription quantitative polymerase chain reaction analysis of the expression of liver new fat generation genes, determination of liver function and inflammatory indicators.The results show that steam scalding of 30 % of the back skin surface area of rats for 30, 20, and 10 s can result in severe skin scalds. Liver Oil Red O staining revealed fat deposition in the scald group, which became more pronounced with longer scald durations. The fat deposition was most evident on the fifth day post-scald and gradually returned to normal over time. This phenomenon is primarily attributed to elevated liver function indicators, including TBIL, ALT, and AST, in the scald group compared to the control group. Additionally, there was activation of peripheral blood inflammatory cells (WBC, MON, NEU,TNF-α, IL-6, and IL-10) and infiltration of inflammatory cells in the liver, along with liver cell edema. The honeycomb-like appearance of peripheral epididymal fat and the significant increase in the expression of lipolytic proteins (UCP1, ATGL, HSL, and P-HSL) were also observed, alongside abnormal expression of key genes (CES and SCD1) associated with liver neovascularization. The changes are caused by the combined effects of these factors.