Distribution, source, and contamination assessment of heavy metals in surface sediments of the Zhifu Bay in northern China.

In this study, 30 surface sediment samples were collected from Zhifu Bay in northern China and analyzed for heavy metals; in addition, their concentrations and pollution status were evaluated. The distributions of Cu and Zn were similar and mainly dominated by fine-grained sediments, whereas the other heavy metal distributions were not very regular. Al was positively correlated with Cu and Zn, and weakly correlated with Pb, As, and Hg. Except for some stations that showed minor enrichment and were unpolluted to moderately polluted by Cr, Cd, and Hg, the overall quality of sediments in the study area was good. Three principal components with eigenvalues >1 were estimated, accounting for 72.06 % of the total variability and representing natural sources, natural and anthropogenic, and anthropogenic sources, respectively.

A Novel Energy Planning Scheme Based on PGA Algorithm and Its Application.

In order to actively respond to the "14th Five-Year Plan," the PGA algorithm is used to develop a new energy planning strategy in this paper. The project can make full use of my country's abundant renewable energy resources, encourage energy conservation and reduction of emissions, improve the energy structure's low-carbon level, support the development of smart green energy, and achieve ecological civilization construction. This solution can show users how much greenhouse gas emissions can be reduced through some environmental changes, as well as the basic issues of meeting the future energy needs. It can display the benefits, costs, and emissions data under different scenarios in the future and use the scenario demonstration method to show energy planning to make energy data more vivid. It allows people, technicians, and decision makers to understand what will happen to China's carbon emissions over time in the next 15 years. This paper innovatively combines a particle swarm optimization algorithm with a genetic algorithm and designs a PGA algorithm for path optimization. In terms of carbon emission reduction, comparative trials demonstrate that the PGA algorithm's path optimization is 58.06 percent greater than the genetic algorithm; In terms of cost, the PGA algorithm's path optimization is 15.72% less expensive than the genetic algorithm's. This article provides a reference path for selecting the best results for future energy planning schemes and provides a new strategy for the "14th Five-Year" energy plan.

Clinical efficacy and mechanism of mesenchymal stromal cells in treatment of COVID-19.

Coronavirus disease 2019 (COVID-19) is a highly infectious epidemic disease that has seriously affected human health worldwide. To date, however, there is still no definitive drug for the treatment of COVID-19. Cell-based therapies could represent a new breakthrough. Over the past several decades, mesenchymal stromal cells (MSCs) have proven to be ideal candidates for the treatment of many viral infectious diseases due to their immunomodulatory and tissue repair or regeneration promoting properties, and several relevant clinical trials for the treatment of COVID-19 have been registered internationally. Herein, we systematically summarize the clinical efficacy of MSCs in the treatment of COVID-19 based on published results, including mortality, time to symptom improvement, computed tomography (CT) imaging, cytokines, and safety, while elaborating on the possible mechanisms underpinning the effects of MSCs, to provide a reference for subsequent studies.