Mechanochemical dynamics of collective cells and hierarchical topological defects in multicellular lumens.

Collective cell dynamics is essential for tissue morphogenesis and various biological functions. However, it remains incompletely understood how mechanical forces and chemical signaling are integrated to direct collective cell behaviors underlying tissue morphogenesis. Here, we propose a three-dimensional (3D) mechanochemical theory accounting for biochemical reaction-diffusion and cellular mechanotransduction to investigate the dynamics of multicellular lumens. We show that the interplay between biochemical signaling and mechanics can trigger either pitchfork or Hopf bifurcation to induce diverse static mechanochemical patterns or generate oscillations with multiple modes both involving marked mechanical deformations in lumens. We uncover the crucial role of mechanochemical feedback in emerging morphodynamics and identify the evolution and morphogenetic functions of hierarchical topological defects including cell-level hexatic defects and tissue-level orientational defects. Our theory captures the common mechanochemical traits of collective dynamics observed in experiments and could provide a mechanistic context for understanding morphological symmetry breaking in 3D lumen-like tissues.

Factors affecting the triage decision-making ability of emergency nurses in Northern China: A multi-center descriptive survey.

INTRODUCTION: The quality of triage decision-making is a prerequisite for priority treatment of critically ill patients and effective utilization of medical resources. Figuring out how to improve triage decision-making is still a topic around the global emergency department. Hence, this study aims to promote an understanding of triage priority care and clarify the elements influencing triage decision-making ability, offering reference for the future to improve the quality of triage decision-making. METHOD: A total of 404 emergency nurses from 11 tertiary hospitals in northern China were surveyed by questionnaire, of which 371 valid questionnaires were submitted (effective rate = 91.83 %). One hospital distributed the questionnaire face-to-face, and the other ten used online form. RESULT: Prior to occupying triage jobs, only a quarter of participants(25.30 %)were qualified. Less than half of emergency nurses (46.60 %) reported taking part in the triage training program. The emergency nurses' triage decision-making ability score was 166.50 ± 26.90(95 %CI 163.75,169.24) in northern China. Gender(P = 0.003), case discussion(P = 0.024), secondary assessment(P = 0.020)and knowledge of triage consensus(P = 0.027) are independent factors influencing triage decision-making ability. CONCLUSION: Emergency triage practices are less implemented in northern China. The triage decision-making ability of emergency nurses in northern China is at a low level. Providing emergency nurses with diverse opportunities to develop their triage skills, finding effective triage training content, form, and frequency, strengthening implement triage consensus, and wisely managing triage nurse resources would improve triage decision-making.