Plasmodium vivax serological exposure markers: PvMSP1-42-induced humoral and memory B-cell response generates long-lived antibodies.

Plasmodium vivax serological exposure markers (SEMs) have emerged as promising tools for the actionable surveillance and implementation of targeted interventions to accelerate malaria elimination. To determine the dynamic profiles of SEMs in current and past P. vivax infections, we screened and selected 11 P. vivax proteins from 210 putative proteins using protein arrays, with a set of serum samples obtained from patients with acute P. vivax and documented past P. vivax infections. Then we used a murine protein immune model to initially investigate the humoral and memory B cell response involved in the generation of long-lived antibodies. We show that of the 11 proteins, especially C-terminal 42-kDa region of P. vivax merozoite surface protein 1 (PvMSP1-42) induced longer-lasting long-lived antibodies, as these antibodies were detected in individuals infected with P. vivax in the 1960-1970s who were not re-infected until 2012. In addition, we provide a potential mechanism for the maintenance of long-lived antibodies after the induction of PvMSP1-42. The results indicate that PvMSP1-42 induces more CD73+CD80+ memory B cells (MBCs) compared to P. vivax GPI-anchored micronemal antigen (PvGAMA), allowing IgG anti-PvMSP1-42 antibodies to be maintained for a long time.

[Occurrence Characteristic and Risk Assessment of Microplastics in Sishui River (Xingyang Section)].

Urban rivers are the main receptors and transporters of microplastic pollution. Understanding the occurrence and environmental risk of microplastics in urban rivers can provide theoretical basis for further control of microplastic pollution. The Sishui River, a tributary of the Yellow River, was selected as the research object. A total of nine water samples were collected from sewage outlets of the Sishui River (Xingyang section). The microplastics in the collected samples were characterized by their sizes, shapes, and colors using a microscope. It was found that microplastics were mostly in the form of transparent fibers and fragments in the water body of sewage outlets, of which the size below 500 µm was relatively high. In addition, PET and PE polymers were identified as the main types using a laser infrared imager. The correlation analysis showed that there was a significant correlation between the PET and PE, indicating that they were similar in origin. The results of the environmental risk assessment showed that the type of microplastics was the main factor affecting the assessment results, whereas the risk values of six sewage samples containing PVC were high. However, the value of pollution load index revealed a low risk level of pollutants in the study area.

Celebrity CEOs, digital transformation and firm performance in China: the moderating role of controlling shareholders and institutional investors.

Background: business leaders' social status significantly impacts companies' strategic direction and performance. Digital transformation, an important tool for companies to enhance competitiveness and resilience, plays an important role in the relationship between executive background and firm performance. Objective: To investigate the impact of celebrity chief executive officers (CEO) on firm performance through digital transformation. Method: Using data from companies listed on the main boards of the Shanghai and Shenzhen Stock Exchanges between 2017 and 2021, this study explored the relationship between celebrity CEOs, digital transformation, and firm performance. Result: Celebrity CEOs significantly enhanced a firm's digital transformation. However, this effect weakened when controlling shareholders and institutional investors held more shares. Additionally, the study showed that celebrity CEOs can improve firm performance through digital transformation. These findings were robust across a range of sensitivity analyses. Conclusion: This study contributes to understanding celebrity CEOs' decision-making motivations and economic impacts from a psychological perspective while also providing valuable insights for driving digital transformation within companies.