N-fixing tree species promote the chemical stability of soil organic carbon in subtropical plantations through increasing the relative contribution of plant-derived lipids

Biodiversity experiments have shown that soil organic carbon(SOC)is not only a function of plant diversity,but is also closely related to the nitrogen(N)-fixing plants.However,the effect of N-fixing trees on SOC chemical stability is still little known,especially with the compounding effects of tree species diversity.An experimental field manipulation was established in subtropical plantations of southern China to explore the impacts of tree species richness(i.e.,one,two,four and six tree species)and with/without N-fixing trees on SOC chemical stability,as indicated by the ratio of easily oxidized organic carbon to SOC(EOC/SOC).Plant-derived C components in terms of hydrolysable plant lipids and lignin phenols were isolated from soils for evaluating their relative contributions to SOC chemical stability.The results showed that N-fixing tree species rather than tree species richness had a significant effect on EOC/SOC.Hydrolysable plant lipids and lignin phenols were negatively correlated with EOC/SOC,while hydrolysable plant lipids contributed more to EOC/SOC than lignin phenols,especially in the occurrence of N-fixing trees.The presence of N-fixing tree species led to an increase in soil N availability and a decrease in fungal abundance,promoting the selective retention of certain key components of hydrolysable plant lipids,thus enhancing SOC chemical stability.These findings underpin the crucial role of N-fixing trees in shaping SOC chemical stability,and therefore,preferential selection of N-fixing tree species in mixed plantations is an appropriate silvicultural strategy to improve SOC chemical stability in subtropical plantations.

Perfluorooctyl bromide nanoemulsions holding MnO_(2) nanoparticles with dual-modality imaging and glutathione depletion enhanced HIFU-eliciting tumor immunogenic cell death

Tumor-targeted immunotherapy is a remarkable breakthrough,offering the inimitable advantage of specific tumoricidal effects with reduced immune-associated cytotoxicity.However,existing platforms suffer from low efficacy,inability to induce strong immunogenic cell death(ICD),and restrained capacity of transforming immune-deserted tumors into immune-cultivated ones.Here,an innovative platform,perfluorooctyl bromide(PFOB)nanoemulsions holding MnO_(2) nanoparticles(MBP),was developed to orchestrate cancer immunotherapy,serving as a theranostic nanoagent for MRI/CT dual-modality imaging and advanced ICD.By simultaneously depleting the GSH and eliciting the ICD effect via highintensity focused ultrasound(HIFU)therapy,the MBP nanomedicine can regulate the tumor immune microenvironment by inducing maturation of dendritic cells(DCs)and facilitating the activation of CD8^(+)and CD4^(+)T cells.The synergistic GSH depletion and HIFU ablation also amplify the inhibition of tumor growth and lung metastasis.Together,these findings inaugurate a new strategy of tumor-targeted immunotherapy,realizing a novel therapeutics paradigm with great clinical significance.

A method for distinguishing benign and malignant pulmonary nodules based on 3D dual path network aided by K-means clustering analysis

In the USA,there were about 1806590 new cancer cases in 2020,and 606520 cancer deaths are expected to have occurred in 2021.Lung cancer has become the leading cause of death from cancer in both men and women(Siegel et al.,2020).Clinical studies show that the five-year survival rate of lung cancer patients after early diagnosis and treatment intervention can reach 80%,compared with that of patients having advanced lung cancer.Thus,the early diagnosis of lung cancer is a key factorto reduce mortality.