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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. [ABSTRACT FROM AUTHOR]

With the rapid development of the biopharmaceutical industry in China, the laboratory animal sector has entered a stage of rapid growth, and the construction of facility operation systems has become increasingly automated and intelligent. Compared to traditional laboratory animal facilities, new facilities require a more specialized technical team for the maintenance of air supply and exhaust systems, air conditioning, automated control, and the entire barrier system. The Lingang Laboratory’s animal facilities accommodate both large and small animals for feeding and experimental purposes. The facility management team has summarized daily maintenance experiences and explored various operational and maintenance modes based on the characteristics of laboratory operation. After analyzing the advantages and disadvantages of three common modes, this paper provides new ideas for the management of these laboratory animal facilities, and offers guidance for peers in choosing the most appropriate professional maintenance mode. [ABSTRACT FROM AUTHOR]

Aviation maintenance is one of the important supports for aircraft operation and a way to ensure safe flight and control operating costs of airlines. Current use of real-time online fault prognostic and health management（PHM）has been far from full-fledged in aviation maintenance，and practical data and cases are in need. This paper puts forward a concept of maintenance mode based on PHM，and then establishes the models of optimization of maintenance plan，controling unscheduled maintenance and error impact analysis. In the simulation， different parameters are input into the PHM system. The maintenance， the cost of maintenance and unscheduled maintenance events before and after the implementation of PHM are simulated， and the advantages of the PHM maintenance mode for reduction in maintenance hours，cost and control of unscheduled maintenance events are validated. The air conditioners system is selected as the verification object，and the results show that，for the single system with the ideal condition that the parameter of PHM is best， compared to the traditional preventive maintenance， the proposed approach can reduce 56% maintenance hours，save 60% maintenance cost，and avoid 88% unscheduled maintenance events based on PHM maintenance mode. [ABSTRACT FROM AUTHOR]

Strategies to treat cancer have focused primarily on the killing of tumor cells. Here, we describe a differential stress resistance (DSR) method that focuses instead on protecting the organism but not cancer cells against chemotherapy. Short-term starved S. cerevisiae or cells lacking proto-oncogene homologs were up to 1,000 times better protected against oxidative stress or chemotherapy drugs than cells expressing the oncogene homolog Ras2[supval19]. Low-glucose or low-serum media also protected primary glial cells but not six different rat and human glioma and neuroblastoma cancer cell lines against hydrogen peroxide or the chemotherapy drug/pro-oxidant cyclophosphamide. Finally, short-term starvation provided complete protection to mice but not to injected neuroblastoma.cells against a high dose of the chemotherapy drug/pro-oxidant etoposide. These studies describe a starvation-based DSR strategy to enhance the efficacy of chemotherapy and suggest that specific agents among those that promote oxidative stress and DNA damage have the potential to maximize the differential toxicity to normal and cancer cells. [ABSTRACT FROM AUTHOR]

• The results have indicated that the distinct thresholds of maintenance mode would reduce the total maintenance cost. • The accurate arrangement of maintenance mode and time would help the inventory control of spare parts. • The proposed PSO approach can generate the same optimal results for small size problems and better results than GA for mediate and large size problems. • The result shows that taking multiple maintenance modes into account would help optimize the total maintenance cost. To decrease the over-maintenance and under-maintenance phenomenon, this paper examined the relationship between facility reliability and lifespan so as to generate the optimal maintenance plan which includes the proper combination of maintenance time and maintenance modes. An age reduction maintenance model is built to describe the deterioration situation of the port facility, and a particle swarm optimization (PSO) based integrated approach is used to solve the model. The sensitivity analysis helps to determine the maintenance mode combination from which the total maintenance cost is minimized. The result shows that taking multiple maintenance modes into account would help optimize the total maintenance cost. In addition, the obvious difference between the reliability thresholds would assist in providing discrepant maintenance service. The results have indicated that when the thresholds of different maintenance mode are overlapped, the total maintenance cost is the highest. [ABSTRACT FROM AUTHOR]