Aim: This study aims to assess the infection risks of flashlight contamination in a stomatology hospital and compare the disinfection effectiveness of alcohol (75%) and disinfecting wipes.Background: The flashlight is...Aim: This study aims to assess the infection risks of flashlight contamination in a stomatology hospital and compare the disinfection effectiveness of alcohol (75%) and disinfecting wipes.Background: The flashlight is a basic non-critical medical device in oral and maxillofacial surgery wards. Wounds are mostly found in oral cavities;therefore, reusable flashlights may be a potential source of nosocomial infections (NIs). However, the microbial flora present in flashlights used in hospitals has not yet been explored. Methods: This study investigated the microbial contamination of 41 flashlights used in a stomatology hospital in Guangzhou in March 2016. Results: Results indicated that 75.6%(31/41) of the flashlights had microbial contamination. Gram-positive bacteria accounted for 72.7%(24/33)of the microbial groups contaminating the flashlights, and Gram-negative bacteria (21.2%, 7/33), and fungi (6.1%, 2/33) constituted the remaining contaminants. The predominantly isolated species was Staphyloccus (66.7%, 22/33), especially Staphylococcus aureus (24.2%, 8/33). Approximately 77.3%(17/22) of the types of bacteria detected in the hands were same as those in the corresponding flashlights. Both the bacterial overstandard and S. aureus detection rates of doctors' flashlights were higher than those of nurses' flashlights (16/17 vs. 14/23, 7/17 vs. 1/23, respectively) (P < 0.05). Moreover, both disinfectants performed excellently, and their eligibility rates were not significantly different (17/17 vs. 14/14) (P>0.05). Conclusion: Flashlights are potential causes of NIs. Disinfecting flashlights could be an effective and practical infection control method.展开更多
A new explosion-proof walking system was designed for the coal mine rescue robot(CMRR) by optimizing the mechanical structure and control algorithm. The mechanical structure innovation lies mainly in the dual-motor dr...A new explosion-proof walking system was designed for the coal mine rescue robot(CMRR) by optimizing the mechanical structure and control algorithm. The mechanical structure innovation lies mainly in the dual-motor drive tracked unit used, which showed high dynamic performance compared with the conventional tracked unit. The control algorithm, developed based on decision trees and neural networking, facilitates autonomous switching between "Velocity-driven Mode" and "Torquedriven Mode". To verify the feasibility and effectiveness of the control strategy, we built a self-designed test platform and used it to debug the control program; we then made a robot prototype and conducted further experiments on single-step, ramp, and rubble terrains. The results show that the proposed walking system has excellent dynamic performance and the control strategy is very efficient, suggesting that a robot with this type of explosion-proof walking system can be successfully applied in Chinese coal mines.展开更多
Objective To study the agreement between ophthalmologists and community health workers in detecting shallow anterior chamber with oblique flashlight test. Methods Totally 425 subjects were given an eye examination in ...Objective To study the agreement between ophthalmologists and community health workers in detecting shallow anterior chamber with oblique flashlight test. Methods Totally 425 subjects were given an eye examination in a community health center. The anterior chamber depth of each subject was examined by one ophthalmologist and two trained community health workers (one nurse and one non-professional health worker) using oblique flashlight test. Inter-observer agreement was determined using the weighted kappa statistic. Results Among the enrolled subjects,148 (35%) were male and 277 (65%) were female. Good agreement was noted in all the three observers. The comparison between the ophthalmologist and the nurse showed a kappa statistic of 0.42 for both eyes (P<0.001). The kappa statistic was 0.54 and 0.52 for right and left eyes respectively between the ophthalmologist and the non-professional health worker (P<0.001). As for agreement between the nurse and the non-professional health worker,the kappa statistic was 0.49 and 0.38 for right and left eyes,respectively (P<0.001). Conclusion The oblique flashlight test may be used as an applicable tool by trained community health workers for screening of shallow anterior chamber and play a role in blindness prevention in community.展开更多
An explosion-proof dual throttling air-conditioning system was put forward to solve the heat dissipation and internal dewing problems of explosion-proof frequency converter in the underground coal mine. This study inv...An explosion-proof dual throttling air-conditioning system was put forward to solve the heat dissipation and internal dewing problems of explosion-proof frequency converter in the underground coal mine. This study investigated the feasibility and benefits of explosion-proof dual throttling cooling and dehumidification air-conditioning system applied to the explosion-proof frequency converter. The physical model of dual throttling air-conditioning system was established and its performance parameter was described by mathematical method. The design calculation of the system has also been done. The experimental result showed that the system reached the steady state at the refrigeration mode after running 45 min, and the maximum internal temperature of the flame-proof cavity was 31.0 ℃. The system reached the steady state at the dehumidification mode after running 37 min. The maximum internal relative humidity and temperature of the flame-proof cavity were 33.4% and 36.3 ℃, respectively. Therefore, the proposed system had excellent ability of heat dissipation and avoided internal dewing. Compared with water cooling system, it was more energy-saving and economical. The airflow field of dual throttling air-conditioning system was also studied by CFD simulation. It was found that the result of CFD numerical simulation was highly consistent with the experimental data.展开更多
The cooling of the high-power thyristor (HPT) in explosion-proof sbcll (EPS) used inmining pit has been a difficult problem for a long time. It has some spectal demands. According toheat pipe’s working principle, thi...The cooling of the high-power thyristor (HPT) in explosion-proof sbcll (EPS) used inmining pit has been a difficult problem for a long time. It has some spectal demands. According toheat pipe’s working principle, this paper introduced a kind of newly devcloped beat pipe radiatorSeveral HPT in EPS can be cooled by one beat pipe. In order to obtain the cooling and forced convection cooling , two dimensionless equations were obtained. This paper also studicd the refation between the surface temperature of HPT and the working electric current. The corresponding curvewas given out. Experiments shown that the beat pipe radistor introdued in this paper could effectively cool the HPT in EPS. It becomes a practical and valuable new technique.展开更多
基金This research was supported by the Extracurricular Scientific Research Program for Students of Sun Yat-Sen University
文摘Aim: This study aims to assess the infection risks of flashlight contamination in a stomatology hospital and compare the disinfection effectiveness of alcohol (75%) and disinfecting wipes.Background: The flashlight is a basic non-critical medical device in oral and maxillofacial surgery wards. Wounds are mostly found in oral cavities;therefore, reusable flashlights may be a potential source of nosocomial infections (NIs). However, the microbial flora present in flashlights used in hospitals has not yet been explored. Methods: This study investigated the microbial contamination of 41 flashlights used in a stomatology hospital in Guangzhou in March 2016. Results: Results indicated that 75.6%(31/41) of the flashlights had microbial contamination. Gram-positive bacteria accounted for 72.7%(24/33)of the microbial groups contaminating the flashlights, and Gram-negative bacteria (21.2%, 7/33), and fungi (6.1%, 2/33) constituted the remaining contaminants. The predominantly isolated species was Staphyloccus (66.7%, 22/33), especially Staphylococcus aureus (24.2%, 8/33). Approximately 77.3%(17/22) of the types of bacteria detected in the hands were same as those in the corresponding flashlights. Both the bacterial overstandard and S. aureus detection rates of doctors' flashlights were higher than those of nurses' flashlights (16/17 vs. 14/23, 7/17 vs. 1/23, respectively) (P < 0.05). Moreover, both disinfectants performed excellently, and their eligibility rates were not significantly different (17/17 vs. 14/14) (P>0.05). Conclusion: Flashlights are potential causes of NIs. Disinfecting flashlights could be an effective and practical infection control method.
基金Project(2012AA041504)supported by the National High-Tech Research and Development Program of ChinaProject(KYLX15_1418)supported by the 2015 Annual General University Graduate Research and Innovation Program of Jiangsu Province,ChinaProject supported by the Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD),China
文摘A new explosion-proof walking system was designed for the coal mine rescue robot(CMRR) by optimizing the mechanical structure and control algorithm. The mechanical structure innovation lies mainly in the dual-motor drive tracked unit used, which showed high dynamic performance compared with the conventional tracked unit. The control algorithm, developed based on decision trees and neural networking, facilitates autonomous switching between "Velocity-driven Mode" and "Torquedriven Mode". To verify the feasibility and effectiveness of the control strategy, we built a self-designed test platform and used it to debug the control program; we then made a robot prototype and conducted further experiments on single-step, ramp, and rubble terrains. The results show that the proposed walking system has excellent dynamic performance and the control strategy is very efficient, suggesting that a robot with this type of explosion-proof walking system can be successfully applied in Chinese coal mines.
基金Supported by Tsinghua-Yue-Yuen Medical Sciences Fund (20240000564) and Norwegian Fredskorpset Exchange Program
文摘Objective To study the agreement between ophthalmologists and community health workers in detecting shallow anterior chamber with oblique flashlight test. Methods Totally 425 subjects were given an eye examination in a community health center. The anterior chamber depth of each subject was examined by one ophthalmologist and two trained community health workers (one nurse and one non-professional health worker) using oblique flashlight test. Inter-observer agreement was determined using the weighted kappa statistic. Results Among the enrolled subjects,148 (35%) were male and 277 (65%) were female. Good agreement was noted in all the three observers. The comparison between the ophthalmologist and the nurse showed a kappa statistic of 0.42 for both eyes (P<0.001). The kappa statistic was 0.54 and 0.52 for right and left eyes respectively between the ophthalmologist and the non-professional health worker (P<0.001). As for agreement between the nurse and the non-professional health worker,the kappa statistic was 0.49 and 0.38 for right and left eyes,respectively (P<0.001). Conclusion The oblique flashlight test may be used as an applicable tool by trained community health workers for screening of shallow anterior chamber and play a role in blindness prevention in community.
基金Supported by the National Basic Research Program of China("973"Program,No.2009CB219907)
文摘An explosion-proof dual throttling air-conditioning system was put forward to solve the heat dissipation and internal dewing problems of explosion-proof frequency converter in the underground coal mine. This study investigated the feasibility and benefits of explosion-proof dual throttling cooling and dehumidification air-conditioning system applied to the explosion-proof frequency converter. The physical model of dual throttling air-conditioning system was established and its performance parameter was described by mathematical method. The design calculation of the system has also been done. The experimental result showed that the system reached the steady state at the refrigeration mode after running 45 min, and the maximum internal temperature of the flame-proof cavity was 31.0 ℃. The system reached the steady state at the dehumidification mode after running 37 min. The maximum internal relative humidity and temperature of the flame-proof cavity were 33.4% and 36.3 ℃, respectively. Therefore, the proposed system had excellent ability of heat dissipation and avoided internal dewing. Compared with water cooling system, it was more energy-saving and economical. The airflow field of dual throttling air-conditioning system was also studied by CFD simulation. It was found that the result of CFD numerical simulation was highly consistent with the experimental data.
文摘The cooling of the high-power thyristor (HPT) in explosion-proof sbcll (EPS) used inmining pit has been a difficult problem for a long time. It has some spectal demands. According toheat pipe’s working principle, this paper introduced a kind of newly devcloped beat pipe radiatorSeveral HPT in EPS can be cooled by one beat pipe. In order to obtain the cooling and forced convection cooling , two dimensionless equations were obtained. This paper also studicd the refation between the surface temperature of HPT and the working electric current. The corresponding curvewas given out. Experiments shown that the beat pipe radistor introdued in this paper could effectively cool the HPT in EPS. It becomes a practical and valuable new technique.
