A Novel Polymer Nanoparticle Polydimethyl Diallyl Ammonium Chloride as An Adjuvant Enhances the Immune Response of SARS-CoV-2 Subunit Vaccine.

The Coronavirus Disease 2019 (COVID-19) pandemic caused by SARS-CoV-2 has a significant impact on global health and the economy. It has underscored the urgent need for a stable, easily produced and effective vaccine. This study presents a novel approach using SARS-CoV-2 spike (S) protein-conjugated nanoparticles (NPs) in combination with cyclic GMP-AMP (cGAMP) (S-NPs-cGAMP) as a subunit vaccine. When mice are immunized, the antiserum of S-NPs-cGAMP group exhibits a 16-fold increase in neutralizing activity against a pseudovirus, compared to S protein group. Additionally, S-NPs-cGAMP induces even higher levels of neutralizing antibodies. Remarkably, the vaccine also triggers a robust humoral immune response, as evidenced by a notable elevation in virus-specific IgG and IgM antibodies. Furthermore, after 42 days of immunization, there is an observed increase in specific immune cell populations in the spleen. CD3+CD4+ and CD3+CD8+T lymphocytes, as well as B220+CD19+ and CD3-CD49b+ NK lymphocytes, show an upward trend, indicating a positive cellular immune response. Moreover, the S-NPs-cGAMP demonstrates promising results against the Delta strain and exhibits good cross-neutralization potential against other variants. These findings suggest that pDMDAAC NPs is potential adjuvant and could serve as a versatile platform for future vaccine development.

Analysis of the Spatial Differentiation and Promotion Potential for Agricultural Eco-Efficiency-Evidence of Pollution's Strong Disposability.

Agricultural eco-efficiency is an important indicator used to measure agriculture's high-quality and sustainable development. Therefore, this paper uses the EBM-Super-ML method with strong disposability of undesired output to calculate Chinese agricultural eco-efficiency and uses a geographical detector to measure the driving force of the factor. The research conclusions are mainly reflected in three aspects. Firstly, from the perspective of eco-efficiency changes, the overall mean value of agricultural eco-efficiency increased by 3.5%, and the regional heterogeneity is significant, with the fastest growth in the eastern region. Secondly, the results of driving force analysis show that the main driving factors of agricultural eco-efficiency divergence are capital inputs, total carbon emissions, labor inputs, agricultural film residues, fertilizer use, and pesticide residues, with driving forces of 0.43, 0.37, 0.34, 0.31, 0.28, and 0.20, respectively. Finally, from the perspective of eco-efficiency improvement potential, the mean value of output improvement potential is 5%, and the input factor is 7%. Among the non-desired outputs, the reduction rate of agricultural films can reach 40%. Among the input factors, labor input has the highest potential for intensive use, while agricultural machinery has a negative effect. Therefore, strengthening the development of the agricultural service industry is of great significance to improve the utilization rate of mechanical equipment and reduce the undesired output of agriculture.

[Enhanced fixation of phenanthrene in soils amended with exotic organic materials].

This paper studied the enhanced fixation of phenanthrene in clay loam soil, sandy silt soil, and silt loam soil under effects of exotic organic materials (EOMs) commercial organic fertilizer and peat. The results showed that after the addition of EOMs, the adsorption isotherms of phenanthrene in test soils were still linear, and distribution was the predominant mechanism for phenanthrene adsorption by soil. The adsorption of phenanthrene was significantly enhanced by the addition of EOMs, and the enhancement of distribution constant (Kd) was positively correlated with the content of soil organic carbon (foc), indicating that the higher the soil foc, the more significant the promotion effect of EOMs addition on phenanthrene adsorption. On the contrary, the desorption of phenanthrene was obviously inhibited by the addition of EOMs. After 64 days of EOMs addition, the extractable amount of phenanthrene was decreased significantly, compared with the control. Since the organic matter content of peat was higher than that of commercial organic fertilizer, the decrease of extractable phenanthrene in soils added with peat was more significant. In addition, the higher the soil foc, the stronger inhibition effect of EOMs on extractability of phenanthrene. On the whole, exotic EOMs could promote the adsorption, while inhibit the desorption and reduce the extractability of phenanthrene in soils.