[ Objective ] This study aimed to investigate the optimal method for extracting RNA from roots of medicinal plant herba violae by comparing the effects of liquid nitrogen grinding method and low-temperature sectioning...[ Objective ] This study aimed to investigate the optimal method for extracting RNA from roots of medicinal plant herba violae by comparing the effects of liquid nitrogen grinding method and low-temperature sectioning method on RNA extraction. [ Method] Roots of herba violae were respectively crushed by using liquid nitrogen grinding method and low-temperature sectioning method to extract RNA. The extraction effects of these two methods were compared based on detec- tion of RNA concentration, purity and integrity and amplification of GAPDH gene by RT-PCR. [Result] The concentration of RNA extracted by liquid nitrogen grinding method and low-temperature sectioning method was 1.21 and 3.57 p^g/~, respectively. Both RNA extracted by these two methods showed two distinct bands after agarose gel electrophoresis. The ratio of brightness of the 28S rRNA to the 18S rRNA bands was greater than 1. PCR amplification showed that the length of GAPDH gene was about 230 bp, which was consistent with the expected result. [ Conclusion ] The experimental results indicated that using low-tempera ture sectioning method to crush the roots of herba violae can meet the needs of most molecular biological experiments including gene cloning and expression analysis, which is an effective and simple method for extracting RNA from plant roots.展开更多
To utilizing the characteristic of radar cross section (RCS) of the low detectable aircraft, a special path planning algorithm to eluding radars by the variable RCS is presented. The algorithm first gives the RCS ch...To utilizing the characteristic of radar cross section (RCS) of the low detectable aircraft, a special path planning algorithm to eluding radars by the variable RCS is presented. The algorithm first gives the RCS changing model of low detectable aircraft, then establishes a threat model of a ground-based air defense system according to the relations between RCS and the radar range coverage. By the new cost functions of the flight path, which consider both factors of the survival probability and the distance of total route, this path planning method is simulated based on the Dijkstra algorithm, and the planned route meets the flight capacity constraints. Simulation results show that using the effective path planning algorithm, the low detectable aircraft can give full play to its own advantage of stealth to achieve the purpose of silent penetration.展开更多
On the purpose of accurate data acquisition for the aeroacoustic testing mostly in open jet test section of aeroacoustic wind tunnel, the large scale anechoic chamber is specifically designed to build the low backgrou...On the purpose of accurate data acquisition for the aeroacoustic testing mostly in open jet test section of aeroacoustic wind tunnel, the large scale anechoic chamber is specifically designed to build the low background noise environment. A newly acoustic test section is presented in this paper, of which the contour is similar as the closed test section, and the wall is fabricated by the fiber fabric, both the characteristics of closed and open jet test section of conventional wind tunnel are combined in it. By thoroughly researching on the acoustics and aerodynamics of this acoustically transparent test section, significant progress in reducing the background noises in test section and improving the ratio of energy of the wind tunnel and some other aspects have been achieved. Acoustically transparent test section behaves better in acoustics and aerodynamics than conventional acoustic test section because of their high definition in detecting the sound sources and great performance in transmitting sounds.展开更多
Objective: In the present study, we report on the results of our investigation of optimum dose monitoring using coagulation and fibrinolytic system indicators during obstetric prophylactic anticoagulant therapy with e...Objective: In the present study, we report on the results of our investigation of optimum dose monitoring using coagulation and fibrinolytic system indicators during obstetric prophylactic anticoagulant therapy with enoxaparin. Study Design: Of 103 cases of cesarean section performed at our hospital, 37 cases were selected for this study after obtain ing their consent for blood collection. Variables of the coagulation and fibrinolytic systems [anti-factor Xa activity, endogenous thrombin potential (ETP), prothrombin time (PT) or international normalized ratio (INR), activated partial thromboplastin time (APTT) and D-dimer levels] were determined. Results: In the 5-day administration group, the anti-factor Xa activitywas 0.0 U/ml on the postoperative day 1, increased to 0.05 U/ml ± 0.04 U/ml on the postoperative day 3, and mildly increased to 0.06 U/ml ± 0.05 U/ml on the postoperative day 5. On the other hand, the anti-factor Xa activity in the 3-day administration group was 0.0 U/ml on the postoperative day 1 (before enoxaparin administration), increased to 0.06 U/ml ± 0.05 U/ml on the postoperative day 3, and significantly decreased to 0.02 U/ml ± 0.03 U/ml on the postoperative day 5 (p = 0.003);thus, the pattern of change was significantly different from that in the 5-day administration group (p = 0.004). Enoxaparin administration did not result in any significant fluctuation of the ETP, and no significant difference was observed between the 5-day and 3-day administration groups. Conclusion: Enoxaparin administration was associated with increase of the anti-factor Xa activity, and prolonged administration led to more sustained increase of the activity.展开更多
基金Supported by National Natural Science Foundation of China(81001700)Project of Sichuan Provincial Education Department(11ZB227,11ZB124)Research Project for the Application Foundation of Sichuan Provincial Science and Technology Department(2012JY0081)
文摘[ Objective ] This study aimed to investigate the optimal method for extracting RNA from roots of medicinal plant herba violae by comparing the effects of liquid nitrogen grinding method and low-temperature sectioning method on RNA extraction. [ Method] Roots of herba violae were respectively crushed by using liquid nitrogen grinding method and low-temperature sectioning method to extract RNA. The extraction effects of these two methods were compared based on detec- tion of RNA concentration, purity and integrity and amplification of GAPDH gene by RT-PCR. [Result] The concentration of RNA extracted by liquid nitrogen grinding method and low-temperature sectioning method was 1.21 and 3.57 p^g/~, respectively. Both RNA extracted by these two methods showed two distinct bands after agarose gel electrophoresis. The ratio of brightness of the 28S rRNA to the 18S rRNA bands was greater than 1. PCR amplification showed that the length of GAPDH gene was about 230 bp, which was consistent with the expected result. [ Conclusion ] The experimental results indicated that using low-tempera ture sectioning method to crush the roots of herba violae can meet the needs of most molecular biological experiments including gene cloning and expression analysis, which is an effective and simple method for extracting RNA from plant roots.
文摘To utilizing the characteristic of radar cross section (RCS) of the low detectable aircraft, a special path planning algorithm to eluding radars by the variable RCS is presented. The algorithm first gives the RCS changing model of low detectable aircraft, then establishes a threat model of a ground-based air defense system according to the relations between RCS and the radar range coverage. By the new cost functions of the flight path, which consider both factors of the survival probability and the distance of total route, this path planning method is simulated based on the Dijkstra algorithm, and the planned route meets the flight capacity constraints. Simulation results show that using the effective path planning algorithm, the low detectable aircraft can give full play to its own advantage of stealth to achieve the purpose of silent penetration.
文摘On the purpose of accurate data acquisition for the aeroacoustic testing mostly in open jet test section of aeroacoustic wind tunnel, the large scale anechoic chamber is specifically designed to build the low background noise environment. A newly acoustic test section is presented in this paper, of which the contour is similar as the closed test section, and the wall is fabricated by the fiber fabric, both the characteristics of closed and open jet test section of conventional wind tunnel are combined in it. By thoroughly researching on the acoustics and aerodynamics of this acoustically transparent test section, significant progress in reducing the background noises in test section and improving the ratio of energy of the wind tunnel and some other aspects have been achieved. Acoustically transparent test section behaves better in acoustics and aerodynamics than conventional acoustic test section because of their high definition in detecting the sound sources and great performance in transmitting sounds.
文摘Objective: In the present study, we report on the results of our investigation of optimum dose monitoring using coagulation and fibrinolytic system indicators during obstetric prophylactic anticoagulant therapy with enoxaparin. Study Design: Of 103 cases of cesarean section performed at our hospital, 37 cases were selected for this study after obtain ing their consent for blood collection. Variables of the coagulation and fibrinolytic systems [anti-factor Xa activity, endogenous thrombin potential (ETP), prothrombin time (PT) or international normalized ratio (INR), activated partial thromboplastin time (APTT) and D-dimer levels] were determined. Results: In the 5-day administration group, the anti-factor Xa activitywas 0.0 U/ml on the postoperative day 1, increased to 0.05 U/ml ± 0.04 U/ml on the postoperative day 3, and mildly increased to 0.06 U/ml ± 0.05 U/ml on the postoperative day 5. On the other hand, the anti-factor Xa activity in the 3-day administration group was 0.0 U/ml on the postoperative day 1 (before enoxaparin administration), increased to 0.06 U/ml ± 0.05 U/ml on the postoperative day 3, and significantly decreased to 0.02 U/ml ± 0.03 U/ml on the postoperative day 5 (p = 0.003);thus, the pattern of change was significantly different from that in the 5-day administration group (p = 0.004). Enoxaparin administration did not result in any significant fluctuation of the ETP, and no significant difference was observed between the 5-day and 3-day administration groups. Conclusion: Enoxaparin administration was associated with increase of the anti-factor Xa activity, and prolonged administration led to more sustained increase of the activity.