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［Objective］ City rail transit vehicles are specifically designed and developed models to adapt to city rail transit lines, differing in operational environment, line parameters, and vehicle configurations from high-speed railway EMU and urban rail transit vehicles. It is essential to conduct research on the maintenance mode for city rail transit vehicles. ［Method］ From the perspective of balancing vehicle reliability and economic efficiency, a suitable maintenance mode for city rail transit vehicles is proposed. The requirements for city rail transit vehicle maintenance from relevant standards are compared and analyzed, using these standards as the primary reference for the maintenance mode formulation. The operational status of vehicles on four launched city rail transit lines in China is surveyed to obtain actual vehicle maintenance data. Two of these lines are selected as examples for analyzing the compatibility of their actual RAMS (reliability, availability, maintainability, and safety) data with component lifespans. The vehicle maintenance system is comprehensively evaluated from the perspectives of safety, economic efficiency, and equipment lifespan compatibility. ［Result & Conclusion］ The formulation of maintenance schedules for city rail transit vehicle must consider two key factors closely related to component lifespans: operating time and mileage. The maintenance mode with optimal compatibility between these two factors should be selected. Routine operational maintenance of city rail transit vehicle is divided into two levels: train inspection (Level 1) and monthly inspection (Level 2), which uses operating time or mileage as assessment indicators. The advanced maintenance mode is categorized into a series of schedule maintenance, medium and major overhauls, or into a Level 3, Level 4, and Level 5 maintenance series.

AIMS: Invasive haemodynamic assessment with a pulmonary artery catheter is often used to guide the management of patients with cardiogenic shock (CS) and may provide important prognostic information. We aimed to assess prognostic associations and relationships to end-organ dysfunction of presenting haemodynamic parameters in CS. METHODS AND RESULTS: The Critical Care Cardiology Trials Network is an investigator-initiated multicenter registry of cardiac intensive care units (CICUs) in North America coordinated by the TIMI Study Group. Patients with CS (2018-2022) who underwent invasive haemodynamic assessment within 24 h of CICU admission were included. Associations of haemodynamic parameters with in-hospital mortality were assessed using logistic regression, and associations with presenting serum lactate were assessed using least squares means regression. Sensitivity analyses were performed excluding patients on temporary mechanical circulatory support and adjusted for vasoactive-inotropic score. Among the 3603 admissions with CS, 1473 had haemodynamic data collected within 24 h of CICU admission. The median cardiac index was 1.9 (25th-75th percentile, 1.6-2.4) L/min/m2 and mean arterial pressure (MAP) was 74 (66-86) mmHg. Parameters associated with mortality included low MAP, low systolic blood pressure, low systemic vascular resistance, elevated right atrial pressure (RAP), elevated RAP/pulmonary capillary wedge pressure ratio, and low pulmonary artery pulsatility index. These associations were generally consistent when controlling for the intensity of background pharmacologic and mechanical haemodynamic support. These parameters were also associated with higher presenting serum lactate. CONCLUSION: In a contemporary CS population, presenting haemodynamic parameters reflecting decreased systemic arterial tone and right ventricular dysfunction are associated with adverse outcomes and systemic hypoperfusion.

Using data from Yushu Agricultural Meteorological Station of Jilin from 2018 to 2023, the impact of different sowing dates of corn is investigated focusing on its growth and yield composition as well as grain quality under global warming. It is also debated whether adjusting the sowing date of corn could be a measure for agriculture to adapt to climate change. Results show that the utilization efficiency of accumulated temperature during the growing season of corn varies with different sowing dates. The accumulated temperature is the highest in the first sowing date and lowest in the fourth sowing date, with an average decrease of 8.3% compared to the first sowing date. Different sowing dates of corn have an impact on the growing period. The duration of the first sowing date for corn is extended by an average of 7.5 days compared to the normal sowing date, while durations of the third and fourth sowing dates are shortened by 5.7 days and 13.8 days, respectively. Different sowing dates have an impact on the yield structure of corn. In the first sowing date, there is an increase in the weight of 100 grains of corn in 2 years during 6 years, while a decrease by 4.8% and 8.7% in the third and fourth sowing dates compared to the normal sowing date. The average number of grains per plant in the first sowing date increases by 0.2%, while decreases by 6.0% and 9.3% in the third and fourth sowing date. Overall, delaying the corn sowing date by 10 days and 20 days results in an average yield reduction of 10.9% and 17.1%. Sowing corn 10 days earlier could increase the yield in some years. The change in sowing dates has little effect on the quality of grains. Therefore, an early corn sowing date can be utilized as a strategy to adapt to climate change in certain regions of Northeast China.

BACKGROUND: Little is known about the prevalence and post-surgical outcomes associated with cardiac intensive care unit (CICU) therapeutics among CICU patients referred for cardiac surgery. OBJECTIVES: The purpose of this study was to investigate the clinical characteristics and outcomes of CICU patients referred for cardiac surgery from the intensive care unit. METHODS: We analyzed characteristics and outcomes of CICU admissions referred from the CICU for cardiac surgery during 2017 to 2020 across 29 centers. The primary outcome was in-hospital mortality. RESULTS: Among 10,321 CICU admissions, 887 (8.6%) underwent cardiac surgery, including 406 (46%) coronary artery bypass graftings, 201 (23%) transplants or ventricular assist devices, 171 (19%) valve surgeries, and 109 (12%) other procedures. Common indications for CICU admission included shock (33.5%) and respiratory insufficiency (24.9%). Preoperative CICU therapies included vasoactive therapy in 52.2%, mechanical circulatory support in 35.9%, renal replacement in 8.2%, mechanical ventilation in 35.7%, and 17.5% with high-flow nasal cannula or noninvasive positive pressure ventilation. In-hospital mortality was 11.7% among all CICU admissions and 9.1% among patients treated with cardiac surgery. After multivariable adjustment, pre-op mechanical circulatory support and renal replacement therapy were associated with mortality, while respiratory support and vasoactive therapy were not. CONCLUSIONS: Nearly 1 in 12 contemporary CICU patients receive cardiac surgery. Despite high preoperative disease severity, CICU admissions undergoing cardiac surgery had a comparable mortality rate to CICU patients overall; highlighting the ability of clinicians to select higher acuity patients with a reasonable perioperative risk.

SignificanceAerosol-cloud interaction affects the cooling of Earth's climate, mostly by activation of aerosols as cloud condensation nuclei that can increase the amount of sunlight reflected back to space. But the controlling physical processes remain uncertain in current climate models. We present a lidar-based technique as a unique remote-sensing tool without thermodynamic assumptions for simultaneously profiling diurnal aerosol and water cloud properties with high resolution. Direct lateral observations of cloud properties show that the vertical structure of low-level water clouds can be far from being perfectly adiabatic. Furthermore, our analysis reveals that, instead of an increase of liquid water path (LWP) as proposed by most general circulation models, elevated aerosol loading can cause a net decrease in LWP.