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In this paper, the theoretical innovation is made on the traditional fire distribution problem. Considering the actual situation of the ship’s fault, based on the principle of multi-objective optimization, the improved distributed genetic algorithm is used for preliminary solution. And the corresponding fault-tolerant control law is formulated to correct the fault-tolerant strategy, so as to ensure the better fire strike effect and maintain a high fault tolerance. Finally, through simulation experiments, it is verified that this method can converge to the optimal solution quickly, and can reduce the loss to the maximum extent when compensating. It has certain research value for combat.

The extraction process of Morchella polyphenols was optimized via response surface methodology. In addition, single-factor optimization of solvent type, ethanol concentration, solid-liquid ratio, ultrasonic time, ultrasonic temperature, and ultrasonic power were optimized. A three-factor and three-level Box-Behnken design was then implemented based on the factors of greater influence. The optimal process was verified as follows: ethanol concentration of 10%, liquid-to-material ratio of 1:67 (g/mL), ultrasonic extraction time of 90 min, ultrasonic extraction temperature of 33, °C and ultrasonic power of 300 W. The polyphenol content extracted from morels under these process conditions was 22.39 mg/g. According to the analysis of response surface experimental data, the model was significant (P<0.000 1), the lack of fit was not significant (P>0.05), and the fitting degree was high (96.2%). The order of the three major factors affecting extraction rate was as follows: ultrasonic temperature > material-to-liquid ratio > ultrasonic power. The polyphenol contents in Morchella esculenta obtained through various extraction conditions were analyzed via HPLC. Ten phenolic compounds were detected. The content curves of these ten phenolic compounds extracted under various single-factor conditions were basically consistent with the data determined via Folin-Ciocalteu colorimetry. [ABSTRACT FROM AUTHOR]

Correlation between nonlinear subharmonic scattering of ultrasound contrast agent microbubbles and ambient pressure is expected to be used for local brain tissue pressure monitoring. Although high-frequency ultrasound has achieved high-resolution imaging of intracranial microvessels, the research on high-frequency subharmonic scattering characteristics of microbubbles is insufficient at present, which restricts the research progress of estimating local brain tissue pressure based on high-frequency subharmonic scattering of microbubbles. Therefore, under the excitation of 10 MHz high-frequency ultrasound, the effects of different acoustic pressures and ambient pressures on the high-frequency subharmonic scattering characteristics of three different ultrasound contrast agents including SonoVue, Sonazoid and Huashengxian were investigated in this in vitro study. Results showed that the subharmonic scattering amplitudes of the three microbubbles increased with the increase of ambient pressure at the peak negative acoustic pressures of 696, 766 and 817 kPa, and there was a favorable linear correlation between subharmonic amplitude and ambient pressure. Under the above three acoustic pressures, the highest correlation coefficient of SonoVue was 0.948 ( P = 0.03), the highest sensitivity of pressure measurement was 0.248 dB/mm Hg and the minimum root mean square error (RMSE) was 2.64 mm Hg. Sonazoid's highest correlation coefficient was 0.982 ( P < 0.01), the highest sensitivity of pressure measurement was 0.052 dB/mm Hg and the minimum RMSE was 1.51 mm Hg. The highest correlation coefficient of Huashengxian was 0.969 ( P = 0.02), the highest sensitivity of pressure measurement was 0.098 dB/mm Hg and the minimum RMSE was 2.00 mm Hg. The above in vitro experimental results indicate that by selecting ultrasound contrast agent microbubbles and optimizing acoustic pressure, the correlation between high-frequency subharmonic scattering of microbubbles and ambient pressure can be improved, the sensitivity of pressure measurement can be upgraded, and the measurement error can be reduced to meet the clinical demand for local brain tissue pressure measurement, which provided an important experimental basis for subsequent research in vivo .

Establishing fever clinic was an important achievement of the fight against severe acute respiratory syndrome (SARS) in 2003, and played an important role in the subsequent outbreaks of H1N1, H7N9 and Middle East respiratory syndrome (MERS). Fever clinics have significant emergency characteristics, but there are no rescue conditions in the fever clinics. Consequently, the problem of establishment and management of fever clinics is still outstanding. Based on the development of fever clinics, this paper analyzes the operational dilemma of fever clinics, explores the measures of establishment and management of fever clinics, and constructs the operational mechanism of fever clinics in order to provide the basis for the emergency management system of public health emergencies, which is suitable for Chinese health system.

Objective: To analyze the using of pre-hospital emergency resources and treatment characteristics of acute alcoholism patients in Guangzhou., Methods: The pre-hospital emergency data of the emergency department of the Second Affiliated Hospital of Guangzhou Medical University from January 1st in 2009 to December 31st in 2018 were obtained from the database of the Guangzhou Emergency Medical Command Center. The related data of patients with acute alcoholism were collected, including gender, age, poisoning severity, treatment results, caller type, number of empty vehicles (empty vehicle was defined as the empty vehicle return caused by the ambulance who did not receive or refused to come to the hospital after the ambulance leaved), departure time (from the ambulance to the completion time), on-site time (from the ambulance to the patient boarding time) and the distribution of pre-hospital emergency time in 24 hours on weekdays and weekends. The relationship between acute alcoholism patients and the peak of in-hospital emergency treatment was analyzed., Results: A total of 2 408 acute alcoholism patients were recorded, among whom 2 109 patients (87.58%) with acute alcoholism,126 (5.23%) with drug poisoning, 67 (2.78%) with chemical poisoning, 3 (0.13%) with pesticide poisoning, and 103 (4.28%) with other poisoning. Acute alcoholism patients were mainly male, with a total of 1 862 cases (88.29%), and the ratio between males and females was 7.54:1. In 2 109 patients with acute alcoholism, 93.41% were in the age range of 18-59 years old. The number of mild patients was 1 717 (81.41%), 1 178 (55.86%) needed further treatment, and no patient died. For the occupation of pre-hospital emergency resources, 43.24% (912/2 109) of acute alcoholism called 120 through 110 with empty vehicles of 36.79% (776/2 109), which were significantly higher than the acute cerebrovascular disease [3.83% (362/9 461), 5.80% (549/9 461), both P < 0.01], acute trauma [24.29% (1 708/7 033), 7.96% (560/7 033), both P < 0.01], acute circulation system disease [2.44% (90/3 694), 2.87% (106/3 694), both P < 0.01], and acute respiratory system disease [0.86% (31/3 606), 1.58% (57/3 606), both P < 0.01]. Furthermore, empty vehicles were more likely to happen through 110 with empty vehicles rate of 51.75% (472/912), which was significantly higher than that through the witness [40.82% (60/147), P < 0.01] and relatives and friends [23.24% (244/1 050), P < 0.01]. The driving time and on-site time of acute alcoholism were significantly shorter than those of acute cerebrovascular disease, acute circulation system disease, and acute respiratory system disease [driving time (minutes): 26 (20, 34) vs. 34 (26, 45), 38 (29, 49), 38 (29, 50); on-site time (minutes): 6 (4, 10) vs. 10 (7, 14), 10 (7, 15), 10 (8, 15), all P < 0.01], but there was no statistical difference as compared with acute trauma [driving time (minutes): 26 (20, 34) vs. 29 (20, 42), on-site time (minutes): 6 (4, 10) vs. 7 (4, 11), both P > 0.05]. The regularity of variation in number of critically acute alcoholism patients was distinctive, which peaked in the period of 21:00-00:00 and bottomed out in the period of 09:00-13:00, which overlapped with the peak flow in the hospital emergency department (17:00-22:00)., Conclusions: Acute alcoholism patients occupy excessive pre-hospital emergency resources, and overlap with the hospital emergency treatment peak. It is necessary to strengthen the public propaganda and education on the rational usage of 120 emergency resources and reduce waste.

With the discovery of the significant medicinal value of alginate oligosaccharides and bioethanol produced by microalgae, alginate lyase has been the focus of research in all fields. Five alginate lyase genes in cluster from Vibrio alginolyticus were cloned and expressed in Escherichia coli. SDS-PAGE and enzyme activity showed that four of the five genes have the activity to degrade alginate. Optimization of the induction conditions, protein purification and enzyme properties of rAlgV3 with the highest enzyme activity were studied. The results showed that the enzyme activity of recombinant enzyme rAlgV3 increased from 2.34×10⁴ U/L to 1.68×10⁵ U/L, which was 7.3 times higher than before. The optimal reaction temperature was 40 °C, and the enzyme was relatively stable between 4 °C and 20 °C. The enzyme had a higher activity between pH 6.5 and 9.0, with the optimum pH 8.0. It showed a wide range of pH that the alginate lyase can exist stably between pH 4.5 and 9.5. Appropriate concentrations of NaCl and Fe²⁺, Fe³⁺ ions promoted enzyme activity. SDS and Cu²⁺ ions inhibited the enzyme activity. The enzyme degraded Poly-M fragments and Poly-G fragments, with a wide range of substrate properties. The degraded product of sodium alginate of rAlgV3 analyzed by ESI-MS mainly was oligosaccharides with a polymerization degree of 2 to 3, which means that rAlgV3 was an endo-type alginate lyase. This enzyme has the potential in the development of third-generation bioethanol and the production of alginate oligosaccharides.