Objective: The laryngeal mask airway (LMA) is an established way for airway control during spontaneous ventila- tion. Its ability to deliver positive pressure ventilation without leakage especially in low flow stat...Objective: The laryngeal mask airway (LMA) is an established way for airway control during spontaneous ventila- tion. Its ability to deliver positive pressure ventilation without leakage especially in low flow states is still controversy. The aim of this study is to test the possibility of using LMA in pediatric closed circuit controlled ventilation, and to find out the optimum cuff volume to perform closed system ventilation. Methods: Twenty children scheduled for elective surgeries were enrolled in a crossover study. Laryngeal mask airway was used. In stage I, the cuff was inflated with the maximum volume of air as rec- ommended by the manufacturers. Adjustment of volume of air inflated into the LMA cuff to the minimum volume to obtain the effective seal was done at stage II. The leak pressure, intracuff pressure and the leak volume were measured in both stages. Results: The cuff filling volume was significantly lower compared to the maximum cuff inflation volume in stage I. Leakage values showed significantly less values in stage II of the study with smaller cuff inflation volumes. The airway leakage pressure was significantly lower in stage fl in comparison to stage I. Cuff inflation pressure in stage I showed marked elevation which dropped significantly after adjustment of cuff volume in stage I1. Conclusion: Laryngeal mask airway is an effective tool to provide closed circuit controlled ventilation in pediatrics. Inflation of the cuff by the minimum volume of air needed to reach the just sealing pressure is suggested to minimize the leakage volume.展开更多
On the basis of analysis of the operating characteristics of SMEs, problems in financial management are pointed out, such as: limited financing channels, lack of internal control systems, weak basic accounting and ba...On the basis of analysis of the operating characteristics of SMEs, problems in financial management are pointed out, such as: limited financing channels, lack of internal control systems, weak basic accounting and backward financial management information construction, and measures like to create a favorable policy and service environment for SMEs through the legal system, to innovate the financial system, to pay attention to nurturing and incentive financial innovation talents, network-building management and to establish related punishment and supervision system, are proposed.展开更多
Based on the critical gap phenomenon of the intestinal capsule robot,a variable-diameter capsule robot with radial gap self-compensation is developed in this paper.With the functional variation principle,a fluid dynam...Based on the critical gap phenomenon of the intestinal capsule robot,a variable-diameter capsule robot with radial gap self-compensation is developed in this paper.With the functional variation principle,a fluid dynamic pressure model satisfying the boundary conditions of the outer surface of capsule robot with screw blades is derived.The critical gap phenomenon is studied theoretically and experimentally based on the end effect and the dynamic balance characteristics of the fluid on the surface of capsule robot.The concept of start-up rotation speed is defined,the relationship between the start-up rotation speed and the spiral parameters of capsule robot is investigated.The strategy for implementing drive and control on several capsule robots under the same rotational magnetic field is proposed,and by defining the start-up curves of several capsule robots with the similar motion regulation as the objective functions,genetic algorithm is employed to optimize the spiral parameters of several capsule robots.Experiments have shown that the proposed drive and control strategy for several capsule robots can be implemented effectively.It has a good prospect of application inside intestine to realize the drive and control on several capsule robots for different medical purposes.展开更多
文摘Objective: The laryngeal mask airway (LMA) is an established way for airway control during spontaneous ventila- tion. Its ability to deliver positive pressure ventilation without leakage especially in low flow states is still controversy. The aim of this study is to test the possibility of using LMA in pediatric closed circuit controlled ventilation, and to find out the optimum cuff volume to perform closed system ventilation. Methods: Twenty children scheduled for elective surgeries were enrolled in a crossover study. Laryngeal mask airway was used. In stage I, the cuff was inflated with the maximum volume of air as rec- ommended by the manufacturers. Adjustment of volume of air inflated into the LMA cuff to the minimum volume to obtain the effective seal was done at stage II. The leak pressure, intracuff pressure and the leak volume were measured in both stages. Results: The cuff filling volume was significantly lower compared to the maximum cuff inflation volume in stage I. Leakage values showed significantly less values in stage II of the study with smaller cuff inflation volumes. The airway leakage pressure was significantly lower in stage fl in comparison to stage I. Cuff inflation pressure in stage I showed marked elevation which dropped significantly after adjustment of cuff volume in stage I1. Conclusion: Laryngeal mask airway is an effective tool to provide closed circuit controlled ventilation in pediatrics. Inflation of the cuff by the minimum volume of air needed to reach the just sealing pressure is suggested to minimize the leakage volume.
文摘On the basis of analysis of the operating characteristics of SMEs, problems in financial management are pointed out, such as: limited financing channels, lack of internal control systems, weak basic accounting and backward financial management information construction, and measures like to create a favorable policy and service environment for SMEs through the legal system, to innovate the financial system, to pay attention to nurturing and incentive financial innovation talents, network-building management and to establish related punishment and supervision system, are proposed.
基金supported by National Natural Science Foundation of China(Grant Nos. 60675054, 60875064)Self-Planned Task of State Key Laboratory of Robotics and System (HIT) (Grant No. SKLRS200903B)
文摘Based on the critical gap phenomenon of the intestinal capsule robot,a variable-diameter capsule robot with radial gap self-compensation is developed in this paper.With the functional variation principle,a fluid dynamic pressure model satisfying the boundary conditions of the outer surface of capsule robot with screw blades is derived.The critical gap phenomenon is studied theoretically and experimentally based on the end effect and the dynamic balance characteristics of the fluid on the surface of capsule robot.The concept of start-up rotation speed is defined,the relationship between the start-up rotation speed and the spiral parameters of capsule robot is investigated.The strategy for implementing drive and control on several capsule robots under the same rotational magnetic field is proposed,and by defining the start-up curves of several capsule robots with the similar motion regulation as the objective functions,genetic algorithm is employed to optimize the spiral parameters of several capsule robots.Experiments have shown that the proposed drive and control strategy for several capsule robots can be implemented effectively.It has a good prospect of application inside intestine to realize the drive and control on several capsule robots for different medical purposes.