The rice planthopper,Sogatella furcifera,is a piercing-sucking insect pest of rice,Oryza sativa.It is responsible for significant crop yield losses,and has developed moderate to high resistance to several commonly use...The rice planthopper,Sogatella furcifera,is a piercing-sucking insect pest of rice,Oryza sativa.It is responsible for significant crop yield losses,and has developed moderate to high resistance to several commonly used chemical insecticides.We investigated the effects of the insect fungal pathogen Isaria javanica,alone and in combination with the chemical insecticide dinotefuran,on S.furcifera under both laboratory and field conditions.Our results show that I.javanica displays high infection efficiency and mortality for different stages of S.furcifera,reducing adult survival,female oviposition and ovary development.Laboratory bioassays showed that the combined use of I.javanica with a low dose(4-16 mg L^(-1))of dinotefuran resulted in higher mortality in S.furcifera than the use of I.javanica or dinotefuran alone.The combined treatment also had more significant effects on several host enzymes,including superoxide dismutase,catalase,peroxidase,and prophenol oxidase activities.In field trials,I.javanica effectively suppressed populations of rice planthoppers to low levels(22-64%of the level in untreated plots).Additional field experiments showed synergistic effects,i.e.,enhanced efficiency,for the control of S.furcifera populations using the combination of a low dose of I.javanica(1×10^(4) conidia mL^(-1))and a low dose of dinotefuran(~4.8-19.2%of normal field use levels),with control effects of>90%and a population level under 50 insects per 100 hills at 3-14 days post-treatment.Our findings indicate that the entomogenous fungus I.javanica offers an attractive biological control addition as part of the integrated pest management(IPM)practices for the control of rice plant pests.展开更多
Objective: To evaluate the role of prevention and control strategies for nosocomial infection in a tertiary teaching hospital during the sudden outbreak of Corona Virus Disease 2019 (COVID-19). Methods: The hospital i...Objective: To evaluate the role of prevention and control strategies for nosocomial infection in a tertiary teaching hospital during the sudden outbreak of Corona Virus Disease 2019 (COVID-19). Methods: The hospital initiated an emergency plan involving multi-departmental defense and control. It adopted a series of nosocomial infection prevention and control measures, including strengthening pre-examination and triage, optimizing the consultation process, improving the hospital’s architectural composition, implementing graded risk management, enhancing personal protection, and implementing staff training and supervision. Descriptive research was used to evaluate the short-term effects of these in-hospital prevention and control strategies. The analysis compared changes in related evaluation indicators between January 24, 2020 and February 12, 2020 (Chinese Lunar New Year’s Eve 2020 to lunar January 19) and the corresponding lunar period of the previous year. Results: Compared to the same period last year, the outpatient fever rate increased by 1.85-fold (P P Conclusion: The nosocomial infection prevention and control strategies implemented during this specific period improved the detection and control abilities for the COVID-19 source of infection and enhanced the compliance with measures. This likely contributed significantly to avoiding the occurrence of nosocomial infection.展开更多
As industrialization and informatization becomemore deeply intertwined,industrial control networks have entered an era of intelligence.The connection between industrial control networks and the external internet is be...As industrialization and informatization becomemore deeply intertwined,industrial control networks have entered an era of intelligence.The connection between industrial control networks and the external internet is becoming increasingly close,which leads to frequent security accidents.This paper proposes a model for the industrial control network.It includes a malware containment strategy that integrates intrusion detection,quarantine,and monitoring.Basedonthismodel,the role of keynodes in the spreadofmalware is studied,a comparisonexperiment is conducted to validate the impact of the containment strategy.In addition,the dynamic behavior of the model is analyzed,the basic reproduction number is computed,and the disease-free and endemic equilibrium of the model is also obtained by the basic reproduction number.Moreover,through simulation experiments,the effectiveness of the containment strategy is validated,the influence of the relevant parameters is analyzed,and the containment strategy is optimized.In otherwords,selective immunity to key nodes can effectively suppress the spread ofmalware andmaintain the stability of industrial control systems.The earlier the immunization of key nodes,the better.Once the time exceeds the threshold,immunizing key nodes is almost ineffective.The analysis provides a better way to contain the malware in the industrial control network.展开更多
Photonic spin Hall effect(PSHE), as a novel physical effect in light–matter interaction, provides an effective metrological method for characterizing the tiny variation in refractive index(RI). In this work, we propo...Photonic spin Hall effect(PSHE), as a novel physical effect in light–matter interaction, provides an effective metrological method for characterizing the tiny variation in refractive index(RI). In this work, we propose a multi-functional PSHE sensor based on VO_(2), a material that can reveal the phase transition behavior. By applying thermal control, the mutual transformation into different phase states of VO_(2) can be realized, which contributes to the flexible switching between multiple RI sensing tasks. When VO_(2) is insulating, the ultrasensitive detection of glucose concentrations in human blood is achieved. When VO_(2) is in a mixed phase, the structure can be designed to distinguish between the normal cells and cancer cells through no-label and real-time monitoring. When VO_(2) is metallic, the proposed PSHE sensor can act as an RI indicator for gas analytes. Compared with other multi-functional sensing devices with the complex structures, our design consists of only one analyte and two VO_(2) layers, which is very simple and elegant. Therefore, the proposed VO_(2)-based PSHE sensor has outstanding advantages such as small size, high sensitivity, no-label, and real-time detection, providing a new approach for investigating tunable multi-functional sensors.展开更多
Objective:To analyze the application effect of feedforward control in outpatient blood specimen management.Methods:1,200 patients who had their venous blood collected in outpatient phlebotomy room of our hospital'...Objective:To analyze the application effect of feedforward control in outpatient blood specimen management.Methods:1,200 patients who had their venous blood collected in outpatient phlebotomy room of our hospital's outpatient clinic from January 2021 to April 2021 were selected as study subjects and divided into 600 cases in the control group and 600 cases in the observation group.The two groups of patients were compared in terms of their satisfaction with the staff,the efficiency of the nurses and the quality of nursing care,turnaround time before specimen analysis,the rejection rate of the blood specimens,and the time of result reporting.Results:After the implementation of feedforward control,patients'satisfaction with staff,nurses work efficiency and quality of care,turnaround time before specimen analysis,specimen rejection rate,and result reporting time in the observation group were significantly higher than those in the control group(P<0.05).Conclusion:The application of feedforward control in the management of outpatient blood specimens has significant effect,which effectively improves patients'satisfaction,enhances the efficiency of nurses and the quality of nursing care,shortens the turnaround time of specimens before analysis and the reporting time of results,and reduces the rejection rate of specimens.展开更多
Detumbling operation toward a rotating target with nutation is meaningful for debris removal but challenging. In this study, a deformable end-effector is first designed based on the requirements for contacting the nut...Detumbling operation toward a rotating target with nutation is meaningful for debris removal but challenging. In this study, a deformable end-effector is first designed based on the requirements for contacting the nutating target. A dual-arm robotic system installed with the deformable end-effectors is modeled and the movement of the end-tips is analyzed. The complex operation of the contact toward a nutating target places strict requirements on control accuracy and controller robustness. Thus, an improvement of the tracking error transformation is proposed and an adaptive sliding mode controller with prescribed performance is designed to guarantee the fast and precise motion of the effector during the contact detumbling.Finally, by employing the proposed effector and the controller,numerical simulations are carried out to verify the effectiveness and efficiency of the contact detumbling toward a nutating target.展开更多
Objective: This paper aims to explore the impact of optimizing details in the operating room on the level of knowledge, attitude, and practice of hospital infection prevention and control by surgeons, as well as the e...Objective: This paper aims to explore the impact of optimizing details in the operating room on the level of knowledge, attitude, and practice of hospital infection prevention and control by surgeons, as well as the effectiveness of infection control. Methods: From January 2022 to June 2023, a total of 120 patients were screened and randomly divided into a control group (routine care and hospital infection management) and a study group (optimizing details in the operating room). Results: Significant differences were found between the two groups in the data of surgeons’ level of knowledge, attitude, and practice in hospital infection prevention and control, infection rates, and nursing satisfaction, with the study group showing better results (P Conclusion: The use of optimizing details in the operating room among surgeons can effectively improve surgeons’ level of knowledge, attitude, and practice in hospital infection prevention and control, reduce infection occurrence, and is worth promoting.展开更多
Strong evidence has accumulated to show a correlation between depression symptoms and inflammatory responses.Moreover,anti-inflammatory treatment has shown partial effectiveness in alleviating depression symptoms.Lyci...Strong evidence has accumulated to show a correlation between depression symptoms and inflammatory responses.Moreover,anti-inflammatory treatment has shown partial effectiveness in alleviating depression symptoms.Lycium barbarum polysaccharide(LBP),derived from Goji berries,exhibits notable antioxidative and anti-inflammatory properties.In our recent double-blinded randomized placebo-controlled trial,we found that LBP significantly reduced depressive symptoms in adolescents with subthreshold depression.It is presumed that the antidepressant effect of LBP may be associated with its influence on inflammatory cytokines.In the double-blinded randomized controlled trial,we enrolled 29 adolescents with subthreshold depression and randomly divided them into an LBP group and a placebo group.In the LBP group,adolescents were given 300 mg/d LBP.A 6-week follow up was completed by 24 adolescents,comprising 14 adolescents from the LBP group(15.36±2.06 years,3 men and 11 women)and 10 adolescents from the placebo group(14.9±1.6 years,2 men and 8 women).Our results showed that after 6 weeks of treatment,the interleukin-17A level in the LBP group was lower than that in the placebo group.Network analysis showed that LBP reduced the correlations and connectivity between inflammatory factors,which were associated with the improvement in depressive symptoms.These findings suggest that 6-week administration of LBP suppresses the immune response by reducing interleukin-17A level,thereby exerting an antidepressant effect.展开更多
Xinqiao Gully is located in the area of the 2008 Wenchuan M_(s)8.0 earthquake in Sichuan province,China.Based on the investigation of the 2023"6-26"Xinqiao Gully debris flow event,this study assessed the eff...Xinqiao Gully is located in the area of the 2008 Wenchuan M_(s)8.0 earthquake in Sichuan province,China.Based on the investigation of the 2023"6-26"Xinqiao Gully debris flow event,this study assessed the effectiveness of the debris flow control project and evaluated the debris flow hazards.Through field investigation and numerical simulation methods,the indicators of flow intensity reduction rate and storage capacity fullness were proposed to quantify the effectiveness of the engineering measures in the debris flow event.The simulation results show that the debris flow control project reduced the flow intensity by41.05%to 64.61%.The storage capacity of the dam decreases gradually from upstream to the mouth of the gully,thus effectively intercepting and controlling the debris flow.By evaluating the debris flow of different recurrence intervals,further measures are recommended for managing debris flow events.展开更多
Objective:To analyze the effects of repetitive transcranial magnetic stimulation combined with motor control training on the treatment of stroke-induced hemiplegia,specifically focusing on the impact on patients’bala...Objective:To analyze the effects of repetitive transcranial magnetic stimulation combined with motor control training on the treatment of stroke-induced hemiplegia,specifically focusing on the impact on patients’balance function and gait.Methods:Fifty-two cases of hemiplegic stroke patients were randomly divided into two groups,26 in the control group and 26 in the observation group,using computer-generated random grouping.All participants underwent conventional treatment and rehabilitation training.In addition to these,the control group received repetitive transcranial magnetic pseudo-stimulation therapy+motor control training,while the observation group received repetitive transcranial magnetic stimulation therapy+motor control training.The balance function and gait parameters of both groups were compared before and after the interventions and assessed the satisfaction of the interventions in both groups.Results:Before the invention,there were no significant differences in balance function scores and each gait parameter between the two groups(P>0.05).However,after the intervention,the observation group showed higher balance function scores compared to the control group(P<0.05).The observation group also exhibited higher step speed and step frequency,longer step length,and a higher overall satisfaction level with the intervention compared to the control group(P<0.05).Conclusion:The combination of repetitive transcranial magnetic stimulation and motor control training in the treatment of stroke-induced hemiplegia has demonstrated positive effects.It not only improves the patient’s balance function and gait but also contributes to overall physical rehabilitation.展开更多
Reinforcement Learning(RL)based control algorithms can learn the control strategies for nonlinear and uncertain environment during interacting with it.Guided by the rewards generated by environment,a RL agent can lear...Reinforcement Learning(RL)based control algorithms can learn the control strategies for nonlinear and uncertain environment during interacting with it.Guided by the rewards generated by environment,a RL agent can learn the control strategy directly in a model-free way instead of investigating the dynamic model of the environment.In the paper,we propose the sampled-data RL control strategy to reduce the computational demand.In the sampled-data control strategy,the whole control system is of a hybrid structure,in which the plant is of continuous structure while the controller(RL agent)adopts a discrete structure.Given that the continuous states of the plant will be the input of the agent,the state–action value function is approximated by the fully connected feed-forward neural networks(FCFFNN).Instead of learning the controller at every step during the interaction with the environment,the learning and acting stages are decoupled to learn the control strategy more effectively through experience replay.In the acting stage,the most effective experience obtained during the interaction with the environment will be stored and during the learning stage,the stored experience will be replayed to customized times,which helps enhance the experience replay process.The effectiveness of proposed approach will be verified by simulation examples.展开更多
[Objectives]The paper was to explore the influence of unmanned aerial vehicle(UAV)low volume spray technology on the control effect of viruliferous thrips and tomato spotted wilt virus(TSWV)under different pesticide c...[Objectives]The paper was to explore the influence of unmanned aerial vehicle(UAV)low volume spray technology on the control effect of viruliferous thrips and tomato spotted wilt virus(TSWV)under different pesticide concentrations,and to explore the effective control nodes and methods of thrips and TSWV.[Methods]According to the occurrence characteristics of thrips and TSWV,the field control effects of 4 pesticides on thrips and TSWV were tested by UAV with the thrips number and disease index as indicators,following the principle of regional and periodic control trials.[Results]In the groups of UAV and artificial prevention and control,4 agents were used alternatively,including 1%emamectin benzoate ME,1.7%abamectin imidacloprid ME,5%emamectin benzoate WDG,and 30%pyriproxyfen dinotefuran SL.There was no significant difference in the control effect of thrips and TSWV among treatment 1(recommended dosage of UAV agent),treatment 2(reduction of recommended dosage of UAV agent by 25%)and treatment 4(recommended dosage of artificial control agent),and the control effects on thrips were more than 83.16%in the 3 treatments.The disease index of TSWV in the 3 treatments decreased from 8.64±1.37 in the blank control group to less than 3,which reached the prevention and control threshold.But treatment 3(reduction of recommended dosage of UAV agent by 50%)did not reach the prevention and control threshold.The disease index of TSWV in the blank control area increased with the increase of the number of live nymphs of thrips,and there was a significant positive correlation,with good fitness.[Conclusions]UAV has a significant impact on the control effect of thrips and TSWV under different pesticide concentrations.In the actual flight control application,it is recommended that the amount of the pesticides is about 3/4 and not less than 1/2 of that of the artificial application.The control area should be extended to 100 m of the ridge of the tobacco field,and UAV is used periodically to control thrips and TSWV for 5 times from pre-transplanting stage to pre-squaring stage of flue-cured tobacco.The control effect is significantly different from the traditional artificial application.展开更多
Objective Current clinical evidence on the effects of home blood pressure telemonitoring(HBPT)on improving blood pressure control comes entirely from developed countries.Thus,we performed this randomized controlled tr...Objective Current clinical evidence on the effects of home blood pressure telemonitoring(HBPT)on improving blood pressure control comes entirely from developed countries.Thus,we performed this randomized controlled trial to evaluate whether HBPT plus support(patient education and clinician remote hypertension management)improves blood pressure control more than usual care(UC)in the Chinese population.Methods This single-center,randomized controlled study was conducted in Beijing,China.Patients aged 30-75 years were eligible for enrolment if they had blood pressure[systolic(SBP)≥140 mmHg and/or diastolic(DBP)≥90 mmHg;or SBP≥130 mmHg and/or DBP≥80 mmHg with diabetes].We recruited 190 patients randomized to either the HBPT or the UC groups for 12 weeks.The primary endpoints were blood pressure reduction and the proportion of patients achieving the target blood pressure.Results Totally,172 patients completed the study,the HBPT plus support group(n=84),and the UC group(n=88).Patients in the plus support group showed a greater reduction in mean ambulatory blood pressure than those in the UC group.The plus support group had a significantly higher proportion of patients who achieved the target blood pressure and maintained a dipper blood pressure pattern at the12th week of follow-up.Additionally,the patients in the plus support group showed lower blood pressure variability and higher drug adherence than those in the UC group.Conclusion HBPT plus additional support results in greater blood pressure reduction,better blood pressure control,a higher proportion of dipper blood pressure patterns,lower blood pressure variability,and higher drug adherence than UC.The development of telemedicine may be the cornerstone of hypertension management in primary care.展开更多
The 20,000-ton combined train running has greatly promoted China’s heavy-haul railway transportation capability. The application of controllable train-tail devices could improve the braking wave of the train and brak...The 20,000-ton combined train running has greatly promoted China’s heavy-haul railway transportation capability. The application of controllable train-tail devices could improve the braking wave of the train and braking synchronism, and alleviate longitudinal impulse.However, the characteristics of the controllable train-tail device such as exhaust area, exhaust duration and exhaust action time are not uniform in practice, and their effects on the longitudinal impulse of the train are not apparent,which is worth studying. In this work, according to the formation of the Datong-Qinhuangdao Railway, the train air brake and longitudinal dynamics simulation system(TABLDSS) is applied to establish a 20,000-ton combined train model with the controllable train-tail device, and the braking characteristics and the longitudinal impulse of the train are calculated synchronously with changing the air exhaust time, exhaust area, and action lag time under initial braking. The results show that the maximum coupler force of the combined train will decrease with the extension of the continuous exhaust time, while the total exhaust time of the controllable train-tail device remains unchanged;the maximum coupler force of the combined train reduces by32.5% with the exhaust area increasing from 70% to 140%;when the lag time between the controllable train-tail device and the master locomotive is more than 1.5 s, the maximum coupler force of the train increases along with the time difference enlargement.展开更多
Epidural electrical stimulation is a new treatment method for spinal cord injury(SCI).Its efficacy and safety have previously been reported.Rehabilitation treatment after epidural electrical stimulation is important t...Epidural electrical stimulation is a new treatment method for spinal cord injury(SCI).Its efficacy and safety have previously been reported.Rehabilitation treatment after epidural electrical stimulation is important to ensure and improve the postoperative efficacy of epidural electrical stimulation in patients with SCI.Considering that electromyography(EMG)-induced rehabilitation treatment can accurately match the muscle contraction of patients with SCI,we designed a study protocol for a prospective,randomized controlled trial.In this trial,on the premise of adjusting the spinal cord electrical stimulator to obtain the maximum EMG signal of the target muscle,patients with SCI receiving epidural electrical stimulation will undergo EMG-induced rehabilitation treatment.Recovery of muscle strength of key muscles,quality of life,safety and therapeutic effects will be monitored.Twenty patients with SCI who are scheduled to undergo epidural electrical stimulation in Shanghai Ruijin Rehabilitation Hospital will be randomly divided into two groups with 10 patients per group.The control group will receive conventional rehabilitation treatment.The EMG-induced rehabilitation group will receive EMG-induced rehabilitation treatment of the target muscles of the upper and lower limbs based on conventional rehabilitation treatment.After rehabilitation treatment,follow up for all patients will occur at 2 weeks and 1,3 and 6 months.The primary outcome measure of this trial will be evaluation of target muscle recovery using the Manual Muscle Testing grading scale.Secondary outcome measures will include modified Barthel Index scores,integrated EMG values,the visual analogue scale,Spinal Cord Independence Measure scores,and modified Ashworth scale scores.The safety indicator will be the incidence of adverse events.This trial will collect data regarding the therapeutic effects of EMG-induced rehabilitation in patients with SCI receiving epidural electrical stimulation for 6 months after rehabilitation treatment.Findings from this trial will help develop rehabilitation methods in patients with SCI after epidural electrical stimulation.This study protocol was approved by Ethics Committee of Shanghai Ruijin Rehabilitation Hospital(Approval No.RKIRB2022-12)on February 15,2022 and was registered with Chinese Clinical Trial Registry(registration number:ChiCTR2200061674;date:June 30,2022).Study protocol version:1.0.展开更多
Reinforcement learning(RL) has roots in dynamic programming and it is called adaptive/approximate dynamic programming(ADP) within the control community. This paper reviews recent developments in ADP along with RL and ...Reinforcement learning(RL) has roots in dynamic programming and it is called adaptive/approximate dynamic programming(ADP) within the control community. This paper reviews recent developments in ADP along with RL and its applications to various advanced control fields. First, the background of the development of ADP is described, emphasizing the significance of regulation and tracking control problems. Some effective offline and online algorithms for ADP/adaptive critic control are displayed, where the main results towards discrete-time systems and continuous-time systems are surveyed, respectively.Then, the research progress on adaptive critic control based on the event-triggered framework and under uncertain environment is discussed, respectively, where event-based design, robust stabilization, and game design are reviewed. Moreover, the extensions of ADP for addressing control problems under complex environment attract enormous attention. The ADP architecture is revisited under the perspective of data-driven and RL frameworks,showing how they promote ADP formulation significantly.Finally, several typical control applications with respect to RL and ADP are summarized, particularly in the fields of wastewater treatment processes and power systems, followed by some general prospects for future research. Overall, the comprehensive survey on ADP and RL for advanced control applications has d emonstrated its remarkable potential within the artificial intelligence era. In addition, it also plays a vital role in promoting environmental protection and industrial intelligence.展开更多
In the context of mosquito control, a plethora of devices have been put on the market. The effectiveness of these devices is not always proven, but some have interesting principles that have the potential to be a good...In the context of mosquito control, a plethora of devices have been put on the market. The effectiveness of these devices is not always proven, but some have interesting principles that have the potential to be a good means of mosquito control. Among these interesting devices are the photonic traps. We have carried out nightly captures of mosquitoes on human baits in the presence and absence of the device. These captures were made during the rainy season in the localities of Zogbadjè and Mènontin. The captures were made under the same atmospheric conditions at the same locations at 5-day intervals. These captures were made twice per house, indoors and outdoors, with one blank capture without the device and one capture with the device. The captured mosquitoes were identified and classified by genus and their aggressiveness determined by calculating the biting rate. A total of 845 mosquitoes were captured during these captures with 296 mosquitoes captured indoors without the device and 132 mosquitoes with the device present. This represents a decrease of 55.40% in culicidae density. Furthermore, a significant decrease was observed in aggressiveness, from 49 to 22 bites per man per night (b/m/n) with the use of the device. This decrease is even more important for nocturnal species such as Anopheles spp. whose aggressiveness decreased by 90%. The present study confirms the effectiveness of the “Electron go out mosquito small lamp” in reducing Culicidae density and mosquito aggression even in the presence of chemotactic interference. However, this study was limited in time and focused only on the ability of the device to reduce mosquito numbers and did not assess its epidemiological efficacy. It is therefore important to extend the work to examine the influence of the use of this device on population health and the occurrence of mosquito-borne diseases, particularly malaria.展开更多
An observer-based adaptive backstepping boundary control is proposed for vibration control of flexible offshore riser systems with unknown nonlinear input dead zone and uncertain environmental disturbances.The control...An observer-based adaptive backstepping boundary control is proposed for vibration control of flexible offshore riser systems with unknown nonlinear input dead zone and uncertain environmental disturbances.The control algorithm can update the control law online through real-time data to make the controller adapt to the environment and improve the control precision.Specifically,based on the adaptive backstepping framework,virtual control laws and Lyapunov functions are designed for each subsystem.Three direction interference observers are designed to track the timevarying boundary disturbance.On this basis,the inverse of the dead zone and linear state transformation are used to compensate for the original system and eliminate the adverse effects of the dead zone.In addition,the stability of the closed-loop system is proven by Lyapunov stability theory.All the system states are bounded,and the vibration offset of the riser converges to a small area of the initial position.Finally,four examples of flexible marine risers are simulated in MATLAB to verify the effectiveness of the proposed controller.展开更多
The stamping-out strategy has been used to control highly pathogenic avian influenza viruses in many countries,driven by the belief that vaccination would not be successful against such viruses and fears that avian in...The stamping-out strategy has been used to control highly pathogenic avian influenza viruses in many countries,driven by the belief that vaccination would not be successful against such viruses and fears that avian influenza virus in vaccinated birds would evolve more rapidly and pose a greater risk to humans.In this review,we summarize the successes in controlling highly pathogenic avian influenza in China and make suggestions regarding the requirements for vaccine selection and effectiveness.In addition,we present evidence that vaccination of poultry not only eliminates human infection with avian influenza virus,but also significantly reduces and abolishes some harmful characteristics of avian influenza virus.展开更多
To investigate the mechanism of rockburst prevention by spraying water onto the surrounding rocks,15 experiments are performed considering different water absorption levels on a single face.High-speed photography and ...To investigate the mechanism of rockburst prevention by spraying water onto the surrounding rocks,15 experiments are performed considering different water absorption levels on a single face.High-speed photography and acoustic emission(AE)system are used to monitor the rockburst process.The effect of water on sandstone rockburst and the prevention mechanism of water on sandstone rockburst are analyzed from the perspective of energy and failure mode.The results show that the higher the ab-sorption degree,the lower the intensity of the rockburst after absorbing water on single side of sand-stone.This is reflected in the fact that with the increase in the water absorption level,the ejection velocity of rockburst fragments is smaller,the depth of the rockburst pit is shallower,and the AE energy is smaller.Under the water absorption level of 100%,the magnitude of rockburst intensity changes from medium to slight.The prevention mechanism of water on sandstone rockburst is that water reduces the capacity of sandstone to store strain energy and accelerates the expansion of shear cracks,which is not conducive to the occurrence of plate cracking before rockburst,and destroys the conditions for rockburst incubation.展开更多
基金funded by grants from the Science and Technology Planning Project of Guangzhou,China(202002020029)the Science and Technology Planning Project of Guangdong Province,China(2019B020217003)+1 种基金the National Key R&D Program of China(2018YFD02003)the National Key Technology Support Program of China(201303019-02)。
文摘The rice planthopper,Sogatella furcifera,is a piercing-sucking insect pest of rice,Oryza sativa.It is responsible for significant crop yield losses,and has developed moderate to high resistance to several commonly used chemical insecticides.We investigated the effects of the insect fungal pathogen Isaria javanica,alone and in combination with the chemical insecticide dinotefuran,on S.furcifera under both laboratory and field conditions.Our results show that I.javanica displays high infection efficiency and mortality for different stages of S.furcifera,reducing adult survival,female oviposition and ovary development.Laboratory bioassays showed that the combined use of I.javanica with a low dose(4-16 mg L^(-1))of dinotefuran resulted in higher mortality in S.furcifera than the use of I.javanica or dinotefuran alone.The combined treatment also had more significant effects on several host enzymes,including superoxide dismutase,catalase,peroxidase,and prophenol oxidase activities.In field trials,I.javanica effectively suppressed populations of rice planthoppers to low levels(22-64%of the level in untreated plots).Additional field experiments showed synergistic effects,i.e.,enhanced efficiency,for the control of S.furcifera populations using the combination of a low dose of I.javanica(1×10^(4) conidia mL^(-1))and a low dose of dinotefuran(~4.8-19.2%of normal field use levels),with control effects of>90%and a population level under 50 insects per 100 hills at 3-14 days post-treatment.Our findings indicate that the entomogenous fungus I.javanica offers an attractive biological control addition as part of the integrated pest management(IPM)practices for the control of rice plant pests.
文摘Objective: To evaluate the role of prevention and control strategies for nosocomial infection in a tertiary teaching hospital during the sudden outbreak of Corona Virus Disease 2019 (COVID-19). Methods: The hospital initiated an emergency plan involving multi-departmental defense and control. It adopted a series of nosocomial infection prevention and control measures, including strengthening pre-examination and triage, optimizing the consultation process, improving the hospital’s architectural composition, implementing graded risk management, enhancing personal protection, and implementing staff training and supervision. Descriptive research was used to evaluate the short-term effects of these in-hospital prevention and control strategies. The analysis compared changes in related evaluation indicators between January 24, 2020 and February 12, 2020 (Chinese Lunar New Year’s Eve 2020 to lunar January 19) and the corresponding lunar period of the previous year. Results: Compared to the same period last year, the outpatient fever rate increased by 1.85-fold (P P Conclusion: The nosocomial infection prevention and control strategies implemented during this specific period improved the detection and control abilities for the COVID-19 source of infection and enhanced the compliance with measures. This likely contributed significantly to avoiding the occurrence of nosocomial infection.
基金Scientific Research Project of Liaoning Province Education Department,Code:LJKQZ20222457&LJKMZ20220781Liaoning Province Nature Fund Project,Code:No.2022-MS-291.
文摘As industrialization and informatization becomemore deeply intertwined,industrial control networks have entered an era of intelligence.The connection between industrial control networks and the external internet is becoming increasingly close,which leads to frequent security accidents.This paper proposes a model for the industrial control network.It includes a malware containment strategy that integrates intrusion detection,quarantine,and monitoring.Basedonthismodel,the role of keynodes in the spreadofmalware is studied,a comparisonexperiment is conducted to validate the impact of the containment strategy.In addition,the dynamic behavior of the model is analyzed,the basic reproduction number is computed,and the disease-free and endemic equilibrium of the model is also obtained by the basic reproduction number.Moreover,through simulation experiments,the effectiveness of the containment strategy is validated,the influence of the relevant parameters is analyzed,and the containment strategy is optimized.In otherwords,selective immunity to key nodes can effectively suppress the spread ofmalware andmaintain the stability of industrial control systems.The earlier the immunization of key nodes,the better.Once the time exceeds the threshold,immunizing key nodes is almost ineffective.The analysis provides a better way to contain the malware in the industrial control network.
基金Project supported by the National Natural Science Foundation of China(Grant No.NSFC 12175107)the Natural Science Foundation of Nanjing Vocational University of Industry Technology,China(Grant No.YK22-02-08)+3 种基金the Qing Lan Project of Jiangsu Province,Chinathe Postgraduate Research&Practice Innovation Program of Jiangsu Province,China(Grant No.KYCX23_0964)the Natural Science Foundation of Jiangsu Province,China(Grant No.BK20230347)the Fund from the Research Center of Industrial Perception and Intelligent Manufacturing Equipment Engineering of Jiangsu Province,China(Grant No.ZK21-05-09)。
文摘Photonic spin Hall effect(PSHE), as a novel physical effect in light–matter interaction, provides an effective metrological method for characterizing the tiny variation in refractive index(RI). In this work, we propose a multi-functional PSHE sensor based on VO_(2), a material that can reveal the phase transition behavior. By applying thermal control, the mutual transformation into different phase states of VO_(2) can be realized, which contributes to the flexible switching between multiple RI sensing tasks. When VO_(2) is insulating, the ultrasensitive detection of glucose concentrations in human blood is achieved. When VO_(2) is in a mixed phase, the structure can be designed to distinguish between the normal cells and cancer cells through no-label and real-time monitoring. When VO_(2) is metallic, the proposed PSHE sensor can act as an RI indicator for gas analytes. Compared with other multi-functional sensing devices with the complex structures, our design consists of only one analyte and two VO_(2) layers, which is very simple and elegant. Therefore, the proposed VO_(2)-based PSHE sensor has outstanding advantages such as small size, high sensitivity, no-label, and real-time detection, providing a new approach for investigating tunable multi-functional sensors.
文摘Objective:To analyze the application effect of feedforward control in outpatient blood specimen management.Methods:1,200 patients who had their venous blood collected in outpatient phlebotomy room of our hospital's outpatient clinic from January 2021 to April 2021 were selected as study subjects and divided into 600 cases in the control group and 600 cases in the observation group.The two groups of patients were compared in terms of their satisfaction with the staff,the efficiency of the nurses and the quality of nursing care,turnaround time before specimen analysis,the rejection rate of the blood specimens,and the time of result reporting.Results:After the implementation of feedforward control,patients'satisfaction with staff,nurses work efficiency and quality of care,turnaround time before specimen analysis,specimen rejection rate,and result reporting time in the observation group were significantly higher than those in the control group(P<0.05).Conclusion:The application of feedforward control in the management of outpatient blood specimens has significant effect,which effectively improves patients'satisfaction,enhances the efficiency of nurses and the quality of nursing care,shortens the turnaround time of specimens before analysis and the reporting time of results,and reduces the rejection rate of specimens.
基金supported by the National Natural Science Foundation of China(11972077,11672035)。
文摘Detumbling operation toward a rotating target with nutation is meaningful for debris removal but challenging. In this study, a deformable end-effector is first designed based on the requirements for contacting the nutating target. A dual-arm robotic system installed with the deformable end-effectors is modeled and the movement of the end-tips is analyzed. The complex operation of the contact toward a nutating target places strict requirements on control accuracy and controller robustness. Thus, an improvement of the tracking error transformation is proposed and an adaptive sliding mode controller with prescribed performance is designed to guarantee the fast and precise motion of the effector during the contact detumbling.Finally, by employing the proposed effector and the controller,numerical simulations are carried out to verify the effectiveness and efficiency of the contact detumbling toward a nutating target.
文摘Objective: This paper aims to explore the impact of optimizing details in the operating room on the level of knowledge, attitude, and practice of hospital infection prevention and control by surgeons, as well as the effectiveness of infection control. Methods: From January 2022 to June 2023, a total of 120 patients were screened and randomly divided into a control group (routine care and hospital infection management) and a study group (optimizing details in the operating room). Results: Significant differences were found between the two groups in the data of surgeons’ level of knowledge, attitude, and practice in hospital infection prevention and control, infection rates, and nursing satisfaction, with the study group showing better results (P Conclusion: The use of optimizing details in the operating room among surgeons can effectively improve surgeons’ level of knowledge, attitude, and practice in hospital infection prevention and control, reduce infection occurrence, and is worth promoting.
基金supported by the National Natural Science Foundation of China,No.81671347(to KL)the Science and Technology Program of Guangzhou of China,No.202007030012(to KFS and KL)the Science and Technology Program of Guangzhou of China,No 202102020735(to RW).
文摘Strong evidence has accumulated to show a correlation between depression symptoms and inflammatory responses.Moreover,anti-inflammatory treatment has shown partial effectiveness in alleviating depression symptoms.Lycium barbarum polysaccharide(LBP),derived from Goji berries,exhibits notable antioxidative and anti-inflammatory properties.In our recent double-blinded randomized placebo-controlled trial,we found that LBP significantly reduced depressive symptoms in adolescents with subthreshold depression.It is presumed that the antidepressant effect of LBP may be associated with its influence on inflammatory cytokines.In the double-blinded randomized controlled trial,we enrolled 29 adolescents with subthreshold depression and randomly divided them into an LBP group and a placebo group.In the LBP group,adolescents were given 300 mg/d LBP.A 6-week follow up was completed by 24 adolescents,comprising 14 adolescents from the LBP group(15.36±2.06 years,3 men and 11 women)and 10 adolescents from the placebo group(14.9±1.6 years,2 men and 8 women).Our results showed that after 6 weeks of treatment,the interleukin-17A level in the LBP group was lower than that in the placebo group.Network analysis showed that LBP reduced the correlations and connectivity between inflammatory factors,which were associated with the improvement in depressive symptoms.These findings suggest that 6-week administration of LBP suppresses the immune response by reducing interleukin-17A level,thereby exerting an antidepressant effect.
基金supported by the project of the China Geological Survey(No.DD20221746)the National Natural Science Foundation of China(Grant Nos.41101086)。
文摘Xinqiao Gully is located in the area of the 2008 Wenchuan M_(s)8.0 earthquake in Sichuan province,China.Based on the investigation of the 2023"6-26"Xinqiao Gully debris flow event,this study assessed the effectiveness of the debris flow control project and evaluated the debris flow hazards.Through field investigation and numerical simulation methods,the indicators of flow intensity reduction rate and storage capacity fullness were proposed to quantify the effectiveness of the engineering measures in the debris flow event.The simulation results show that the debris flow control project reduced the flow intensity by41.05%to 64.61%.The storage capacity of the dam decreases gradually from upstream to the mouth of the gully,thus effectively intercepting and controlling the debris flow.By evaluating the debris flow of different recurrence intervals,further measures are recommended for managing debris flow events.
文摘Objective:To analyze the effects of repetitive transcranial magnetic stimulation combined with motor control training on the treatment of stroke-induced hemiplegia,specifically focusing on the impact on patients’balance function and gait.Methods:Fifty-two cases of hemiplegic stroke patients were randomly divided into two groups,26 in the control group and 26 in the observation group,using computer-generated random grouping.All participants underwent conventional treatment and rehabilitation training.In addition to these,the control group received repetitive transcranial magnetic pseudo-stimulation therapy+motor control training,while the observation group received repetitive transcranial magnetic stimulation therapy+motor control training.The balance function and gait parameters of both groups were compared before and after the interventions and assessed the satisfaction of the interventions in both groups.Results:Before the invention,there were no significant differences in balance function scores and each gait parameter between the two groups(P>0.05).However,after the intervention,the observation group showed higher balance function scores compared to the control group(P<0.05).The observation group also exhibited higher step speed and step frequency,longer step length,and a higher overall satisfaction level with the intervention compared to the control group(P<0.05).Conclusion:The combination of repetitive transcranial magnetic stimulation and motor control training in the treatment of stroke-induced hemiplegia has demonstrated positive effects.It not only improves the patient’s balance function and gait but also contributes to overall physical rehabilitation.
基金supported by Imperial College London,UK,King’s College London,UK and Engineering and Physical Sciences Research Council(EPSRC),UK.
文摘Reinforcement Learning(RL)based control algorithms can learn the control strategies for nonlinear and uncertain environment during interacting with it.Guided by the rewards generated by environment,a RL agent can learn the control strategy directly in a model-free way instead of investigating the dynamic model of the environment.In the paper,we propose the sampled-data RL control strategy to reduce the computational demand.In the sampled-data control strategy,the whole control system is of a hybrid structure,in which the plant is of continuous structure while the controller(RL agent)adopts a discrete structure.Given that the continuous states of the plant will be the input of the agent,the state–action value function is approximated by the fully connected feed-forward neural networks(FCFFNN).Instead of learning the controller at every step during the interaction with the environment,the learning and acting stages are decoupled to learn the control strategy more effectively through experience replay.In the acting stage,the most effective experience obtained during the interaction with the environment will be stored and during the learning stage,the stored experience will be replayed to customized times,which helps enhance the experience replay process.The effectiveness of proposed approach will be verified by simulation examples.
文摘[Objectives]The paper was to explore the influence of unmanned aerial vehicle(UAV)low volume spray technology on the control effect of viruliferous thrips and tomato spotted wilt virus(TSWV)under different pesticide concentrations,and to explore the effective control nodes and methods of thrips and TSWV.[Methods]According to the occurrence characteristics of thrips and TSWV,the field control effects of 4 pesticides on thrips and TSWV were tested by UAV with the thrips number and disease index as indicators,following the principle of regional and periodic control trials.[Results]In the groups of UAV and artificial prevention and control,4 agents were used alternatively,including 1%emamectin benzoate ME,1.7%abamectin imidacloprid ME,5%emamectin benzoate WDG,and 30%pyriproxyfen dinotefuran SL.There was no significant difference in the control effect of thrips and TSWV among treatment 1(recommended dosage of UAV agent),treatment 2(reduction of recommended dosage of UAV agent by 25%)and treatment 4(recommended dosage of artificial control agent),and the control effects on thrips were more than 83.16%in the 3 treatments.The disease index of TSWV in the 3 treatments decreased from 8.64±1.37 in the blank control group to less than 3,which reached the prevention and control threshold.But treatment 3(reduction of recommended dosage of UAV agent by 50%)did not reach the prevention and control threshold.The disease index of TSWV in the blank control area increased with the increase of the number of live nymphs of thrips,and there was a significant positive correlation,with good fitness.[Conclusions]UAV has a significant impact on the control effect of thrips and TSWV under different pesticide concentrations.In the actual flight control application,it is recommended that the amount of the pesticides is about 3/4 and not less than 1/2 of that of the artificial application.The control area should be extended to 100 m of the ridge of the tobacco field,and UAV is used periodically to control thrips and TSWV for 5 times from pre-transplanting stage to pre-squaring stage of flue-cured tobacco.The control effect is significantly different from the traditional artificial application.
基金The Project of the National Ministry of Industry and Information Technology[2020-0103-3-1-1]The Project of Beijing Science and technology“capital characteristics”[Z181100001718007]。
文摘Objective Current clinical evidence on the effects of home blood pressure telemonitoring(HBPT)on improving blood pressure control comes entirely from developed countries.Thus,we performed this randomized controlled trial to evaluate whether HBPT plus support(patient education and clinician remote hypertension management)improves blood pressure control more than usual care(UC)in the Chinese population.Methods This single-center,randomized controlled study was conducted in Beijing,China.Patients aged 30-75 years were eligible for enrolment if they had blood pressure[systolic(SBP)≥140 mmHg and/or diastolic(DBP)≥90 mmHg;or SBP≥130 mmHg and/or DBP≥80 mmHg with diabetes].We recruited 190 patients randomized to either the HBPT or the UC groups for 12 weeks.The primary endpoints were blood pressure reduction and the proportion of patients achieving the target blood pressure.Results Totally,172 patients completed the study,the HBPT plus support group(n=84),and the UC group(n=88).Patients in the plus support group showed a greater reduction in mean ambulatory blood pressure than those in the UC group.The plus support group had a significantly higher proportion of patients who achieved the target blood pressure and maintained a dipper blood pressure pattern at the12th week of follow-up.Additionally,the patients in the plus support group showed lower blood pressure variability and higher drug adherence than those in the UC group.Conclusion HBPT plus additional support results in greater blood pressure reduction,better blood pressure control,a higher proportion of dipper blood pressure patterns,lower blood pressure variability,and higher drug adherence than UC.The development of telemedicine may be the cornerstone of hypertension management in primary care.
基金China National Railway Group Co.,Ltd(N2020J037).
文摘The 20,000-ton combined train running has greatly promoted China’s heavy-haul railway transportation capability. The application of controllable train-tail devices could improve the braking wave of the train and braking synchronism, and alleviate longitudinal impulse.However, the characteristics of the controllable train-tail device such as exhaust area, exhaust duration and exhaust action time are not uniform in practice, and their effects on the longitudinal impulse of the train are not apparent,which is worth studying. In this work, according to the formation of the Datong-Qinhuangdao Railway, the train air brake and longitudinal dynamics simulation system(TABLDSS) is applied to establish a 20,000-ton combined train model with the controllable train-tail device, and the braking characteristics and the longitudinal impulse of the train are calculated synchronously with changing the air exhaust time, exhaust area, and action lag time under initial braking. The results show that the maximum coupler force of the combined train will decrease with the extension of the continuous exhaust time, while the total exhaust time of the controllable train-tail device remains unchanged;the maximum coupler force of the combined train reduces by32.5% with the exhaust area increasing from 70% to 140%;when the lag time between the controllable train-tail device and the master locomotive is more than 1.5 s, the maximum coupler force of the train increases along with the time difference enlargement.
基金supported by a grant from Shanghai Municipal Health Commission(General Program),No.202140221(to YB)Shanghai Municipal Key Clinical Specialty,No.shslczdzk02701。
文摘Epidural electrical stimulation is a new treatment method for spinal cord injury(SCI).Its efficacy and safety have previously been reported.Rehabilitation treatment after epidural electrical stimulation is important to ensure and improve the postoperative efficacy of epidural electrical stimulation in patients with SCI.Considering that electromyography(EMG)-induced rehabilitation treatment can accurately match the muscle contraction of patients with SCI,we designed a study protocol for a prospective,randomized controlled trial.In this trial,on the premise of adjusting the spinal cord electrical stimulator to obtain the maximum EMG signal of the target muscle,patients with SCI receiving epidural electrical stimulation will undergo EMG-induced rehabilitation treatment.Recovery of muscle strength of key muscles,quality of life,safety and therapeutic effects will be monitored.Twenty patients with SCI who are scheduled to undergo epidural electrical stimulation in Shanghai Ruijin Rehabilitation Hospital will be randomly divided into two groups with 10 patients per group.The control group will receive conventional rehabilitation treatment.The EMG-induced rehabilitation group will receive EMG-induced rehabilitation treatment of the target muscles of the upper and lower limbs based on conventional rehabilitation treatment.After rehabilitation treatment,follow up for all patients will occur at 2 weeks and 1,3 and 6 months.The primary outcome measure of this trial will be evaluation of target muscle recovery using the Manual Muscle Testing grading scale.Secondary outcome measures will include modified Barthel Index scores,integrated EMG values,the visual analogue scale,Spinal Cord Independence Measure scores,and modified Ashworth scale scores.The safety indicator will be the incidence of adverse events.This trial will collect data regarding the therapeutic effects of EMG-induced rehabilitation in patients with SCI receiving epidural electrical stimulation for 6 months after rehabilitation treatment.Findings from this trial will help develop rehabilitation methods in patients with SCI after epidural electrical stimulation.This study protocol was approved by Ethics Committee of Shanghai Ruijin Rehabilitation Hospital(Approval No.RKIRB2022-12)on February 15,2022 and was registered with Chinese Clinical Trial Registry(registration number:ChiCTR2200061674;date:June 30,2022).Study protocol version:1.0.
基金supported in part by the National Natural Science Foundation of China(62222301, 62073085, 62073158, 61890930-5, 62021003)the National Key Research and Development Program of China (2021ZD0112302, 2021ZD0112301, 2018YFC1900800-5)Beijing Natural Science Foundation (JQ19013)。
文摘Reinforcement learning(RL) has roots in dynamic programming and it is called adaptive/approximate dynamic programming(ADP) within the control community. This paper reviews recent developments in ADP along with RL and its applications to various advanced control fields. First, the background of the development of ADP is described, emphasizing the significance of regulation and tracking control problems. Some effective offline and online algorithms for ADP/adaptive critic control are displayed, where the main results towards discrete-time systems and continuous-time systems are surveyed, respectively.Then, the research progress on adaptive critic control based on the event-triggered framework and under uncertain environment is discussed, respectively, where event-based design, robust stabilization, and game design are reviewed. Moreover, the extensions of ADP for addressing control problems under complex environment attract enormous attention. The ADP architecture is revisited under the perspective of data-driven and RL frameworks,showing how they promote ADP formulation significantly.Finally, several typical control applications with respect to RL and ADP are summarized, particularly in the fields of wastewater treatment processes and power systems, followed by some general prospects for future research. Overall, the comprehensive survey on ADP and RL for advanced control applications has d emonstrated its remarkable potential within the artificial intelligence era. In addition, it also plays a vital role in promoting environmental protection and industrial intelligence.
文摘In the context of mosquito control, a plethora of devices have been put on the market. The effectiveness of these devices is not always proven, but some have interesting principles that have the potential to be a good means of mosquito control. Among these interesting devices are the photonic traps. We have carried out nightly captures of mosquitoes on human baits in the presence and absence of the device. These captures were made during the rainy season in the localities of Zogbadjè and Mènontin. The captures were made under the same atmospheric conditions at the same locations at 5-day intervals. These captures were made twice per house, indoors and outdoors, with one blank capture without the device and one capture with the device. The captured mosquitoes were identified and classified by genus and their aggressiveness determined by calculating the biting rate. A total of 845 mosquitoes were captured during these captures with 296 mosquitoes captured indoors without the device and 132 mosquitoes with the device present. This represents a decrease of 55.40% in culicidae density. Furthermore, a significant decrease was observed in aggressiveness, from 49 to 22 bites per man per night (b/m/n) with the use of the device. This decrease is even more important for nocturnal species such as Anopheles spp. whose aggressiveness decreased by 90%. The present study confirms the effectiveness of the “Electron go out mosquito small lamp” in reducing Culicidae density and mosquito aggression even in the presence of chemotactic interference. However, this study was limited in time and focused only on the ability of the device to reduce mosquito numbers and did not assess its epidemiological efficacy. It is therefore important to extend the work to examine the influence of the use of this device on population health and the occurrence of mosquito-borne diseases, particularly malaria.
基金financially supported by the Sichuan Science and Technology Program(Grant No.2023NSFSC1980)。
文摘An observer-based adaptive backstepping boundary control is proposed for vibration control of flexible offshore riser systems with unknown nonlinear input dead zone and uncertain environmental disturbances.The control algorithm can update the control law online through real-time data to make the controller adapt to the environment and improve the control precision.Specifically,based on the adaptive backstepping framework,virtual control laws and Lyapunov functions are designed for each subsystem.Three direction interference observers are designed to track the timevarying boundary disturbance.On this basis,the inverse of the dead zone and linear state transformation are used to compensate for the original system and eliminate the adverse effects of the dead zone.In addition,the stability of the closed-loop system is proven by Lyapunov stability theory.All the system states are bounded,and the vibration offset of the riser converges to a small area of the initial position.Finally,four examples of flexible marine risers are simulated in MATLAB to verify the effectiveness of the proposed controller.
基金This work was supported by the National Key Research andDevelopment Programof China(2021YFD1800200 and2021YFC2301700).
文摘The stamping-out strategy has been used to control highly pathogenic avian influenza viruses in many countries,driven by the belief that vaccination would not be successful against such viruses and fears that avian influenza virus in vaccinated birds would evolve more rapidly and pose a greater risk to humans.In this review,we summarize the successes in controlling highly pathogenic avian influenza in China and make suggestions regarding the requirements for vaccine selection and effectiveness.In addition,we present evidence that vaccination of poultry not only eliminates human infection with avian influenza virus,but also significantly reduces and abolishes some harmful characteristics of avian influenza virus.
基金The financial support from the National Natural Science Foun-dation of China(Grant Nos.52074299 and 41941018)the Fundamental Research Funds for the Central Universities of China(Grant No.2023JCCXSB02)are gratefully acknowledged.
文摘To investigate the mechanism of rockburst prevention by spraying water onto the surrounding rocks,15 experiments are performed considering different water absorption levels on a single face.High-speed photography and acoustic emission(AE)system are used to monitor the rockburst process.The effect of water on sandstone rockburst and the prevention mechanism of water on sandstone rockburst are analyzed from the perspective of energy and failure mode.The results show that the higher the ab-sorption degree,the lower the intensity of the rockburst after absorbing water on single side of sand-stone.This is reflected in the fact that with the increase in the water absorption level,the ejection velocity of rockburst fragments is smaller,the depth of the rockburst pit is shallower,and the AE energy is smaller.Under the water absorption level of 100%,the magnitude of rockburst intensity changes from medium to slight.The prevention mechanism of water on sandstone rockburst is that water reduces the capacity of sandstone to store strain energy and accelerates the expansion of shear cracks,which is not conducive to the occurrence of plate cracking before rockburst,and destroys the conditions for rockburst incubation.