To ensure the safe transportation of radioactive materials,numerous countries have established specific standards.For the transfer of fissile materials,it is imperative that the material within the packaging remains i...To ensure the safe transportation of radioactive materials,numerous countries have established specific standards.For the transfer of fissile materials,it is imperative that the material within the packaging remains in a subcritical state during routine,normal,and accidental transport conditions.In the event of an accident,the rods within the storage tank may become rearranged,introducing uncertainty that must be accounted for to ensure that criticality analysis results are conservative.Historically,this uncertainty was addressed overly conservatively due to limited research on non-uniform arrangement scenarios,which proved unsuitable for criticality safety analysis of spent fuel packages.This paper introduced three distinct methods to non-uniformly rearrange fuel rods—Uniform Arrangement by Blocks,Layer-by-Layer Determination,and Birdcage Deformation—and meticulously evaluates the influences of rod rearrangement on the effective multiplication factor of neutrons,k eff,utilizing the Monte Carlo method.Ultimately,this study presents a holistic method capable of encompassing the entire spectrum of potential effects stemming from the rearrangement of fuel rods during rods mispositioning accident.By augmenting the safety margin,this approach proves to be adeptly suited for the criticality safety analysis of nuclear fuel transport containers.展开更多
Background:While the treatment of metastatic renal cell carcinoma(mRCC)is evolving due to immune checkpoint inhibitors(ICIs),optimal strategies for later lines of therapy have yet to be defined.The combination of lenv...Background:While the treatment of metastatic renal cell carcinoma(mRCC)is evolving due to immune checkpoint inhibitors(ICIs),optimal strategies for later lines of therapy have yet to be defined.The combination of lenvatinib and everolimus represents a viable option,and the present review aimed to summarize its activity,effectiveness,and safety.Methods:A systematic review of the literature was conducted using PubMed,targeting studies published between 2018 and 2025.Eligible studies included English-language prospective and retrospective trials reporting survival outcomes in mRCC patients treated with lenvatinib and everolimus after at least one ICI-containing regimen.Results:Nine studies met the inclusion criteria,encompassing a total of 441 patients.The lenvatinib and everolimus combination was primarily used in the third and subsequent lines of therapy.Median overall survival ranged from 7.5 to 24.5 months,while median progression-free survival was more consistent,between 6.1 and 6.7 months,except for one study reporting 12.9 months.Objective response rates varied widely(14.0%–55.7%).Adverse events of grade≥3 did not exceed the expected rate,with diarrhoea and proteinuria as the most reported events.Dose reductions and treatment discontinuations due to toxicity occurred but were generally lower than in prior pivotal trials.Conclusions:Real-world evidence suggests that lenvatinib and everolimus represent an effective and safe option after ICI failure in mRCC patients.Nevertheless,the lack of randomized phase III trials and the heterogeneity of existing studies highlight the need for more robust prospective research to guide post-ICI therapeutic strategies.展开更多
Intrathecal administration of human umbilical cord mesenchymal stem cells may be a promising approach for the treatment of stroke,but its safety,effectiveness,and mechanism remain to be elucidated.In this study,good m...Intrathecal administration of human umbilical cord mesenchymal stem cells may be a promising approach for the treatment of stroke,but its safety,effectiveness,and mechanism remain to be elucidated.In this study,good manufacturing practice-grade human umbilical cord mesenchymal stem cells(5×105 and 1×106 cells)and saline were administered by cerebellomedullary cistern injection 72 hours after stroke induced by middle cerebral artery occlusion in rats.The results showed(1)no significant difference in mortality or general conditions among the three groups.There was no abnormal differentiation or tumor formation in various organs of rats in any group.(2)Compared with saline-treated animals,those treated with human umbilical cord mesenchymal stem cells showed significant functional recovery and reduced infarct volume,with no significant differences between different human umbilical cord mesenchymal stem cell doses.(3)Human umbilical cord mesenchymal stem cells were found in the ischemic brain after 14 and 28 days of follow-up,and the number of positive cells significantly decreased over time.(4)Neuronal nuclei expression in the human umbilical cord mesenchymal stem cell group was greater than that in the saline group,while glial fibrillary acidic protein and ionized calcium binding adaptor molecule 1 expression levels decreased.(5)Human umbilical cord mesenchymal stem cell treatment increased the number of CD31+microvessels and doublecortin-positive cells after ischemic stroke.Human umbilical cord mesenchymal stem cells also upregulated the expression of CD31+/Ki67+.(6)At 14 days after intrathecal administration,brain-derived neurotrophic factor expression in the peri-infarct area and the concentrations of brain-derived neurotrophic factor in the cerebrospinal fluid in both human umbilical cord mesenchymal stem cell groups were significantly greater than those in the saline group and persisted until the 28th day.Taken together,these results indicate that the intrathecal administration of human umbilical cord mesenchymal stem cells via cerebellomedullary cistern injection is safe and effective for the treatment of ischemic stroke in rats.The mechanisms may include alleviating the local inflammatory response in the peri-infarct region,promoting neurogenesis and angiogenesis,and enhancing the production of neurotrophic factors.展开更多
The integration of artificial intelligence(AI)technology,particularly large language models(LLMs),has become essential across various sectors due to their advanced language comprehension and generation capabilities.De...The integration of artificial intelligence(AI)technology,particularly large language models(LLMs),has become essential across various sectors due to their advanced language comprehension and generation capabilities.Despite their transformative impact in fields such as machine translation and intelligent dialogue systems,LLMs face significant challenges.These challenges include safety,security,and privacy concerns that undermine their trustworthiness and effectiveness,such as hallucinations,backdoor attacks,and privacy leakage.Previous works often conflated safety issues with security concerns.In contrast,our study provides clearer and more reasonable definitions for safety,security,and privacy within the context of LLMs.Building on these definitions,we provide a comprehensive overview of the vulnerabilities and defense mechanisms related to safety,security,and privacy in LLMs.Additionally,we explore the unique research challenges posed by LLMs and suggest potential avenues for future research,aiming to enhance the robustness and reliability of LLMs in the face of emerging threats.展开更多
With the anticipated growth in air traffic complexity in the coming years,future civil aviation transportation system(CATS)is transforming into a complex cyber–physical–social system,surpassing all previous experien...With the anticipated growth in air traffic complexity in the coming years,future civil aviation transportation system(CATS)is transforming into a complex cyber–physical–social system,surpassing all previous experiences in the history of civil aviation safety management.Therefore,a new safety concept based on a system-of-systems(SoS)perspective is proposed for the next-generation aviation.This article begins by elucidating the complexity of existing aviation risks and emphasizing the necessity for an updated safety concept.It then presents the challenges of current safety management and potential solutions from the new SoS perspective.To address future risks,the concept of SoS safety is introduced with the inspiration of the human immune system in terms of capability,logic,and architecture,which can serve as a guiding framework and methodology for safety engineering in complex large-scale CATS.This concept indicates the transition from“process and outcome-oriented”to“capability-oriented”intelligent safety management.Our research highlights the development directions and potential technological areas that need to be addressed at different stages of SoS safety.The integration of SoS design and operation through rapid iterations enabled by artificial intelligence(AI)will ultimately achieve endogenous SoS safety.展开更多
Surface engineering plays a crucial role in improving the performance of high energy materials,and polydopamine(PDA)is widely used in the field of energetic materials for surface modification and functionalization.In ...Surface engineering plays a crucial role in improving the performance of high energy materials,and polydopamine(PDA)is widely used in the field of energetic materials for surface modification and functionalization.In order to obtain high-quality HMX@PDA-based PBX explosives with high sphericity and a narrow particle size distribution,composite microspheres were prepared using co-axial droplet microfluidic technology.The formation mechanism,thermal behavior,mechanical sensitivity,electrostatic spark sensitivity,compressive strength,and combustion performance of the microspheres were investigated.The results show that PDA can effectively enhance the interfacial interaction between the explosive particles and the binder under the synergistic effect of chemical bonds and the physical"mechanical interlocking"structure.Interface reinforcement causes the thermal decomposition temperature of the sample microspheres to move to a higher temperature,with the sensitivity to impact,friction,and electrostatic sparks(for S-1)increasing by 12.5%,31.3%,and 81.5%respectively,and the compressive strength also increased by 30.7%,effectively enhancing the safety performance of the microspheres.Therefore,this study provides an effective and universal strategy for preparing high-quality functional explosives,and also provides some reference for the safe use of energetic materials in practical applications.展开更多
Battery technology plays a crucial role across various sectors,powering devices from smartphones to electric vehicles and supporting grid-scale energy storage.To ensure their safety and efficiency,batteries must be ev...Battery technology plays a crucial role across various sectors,powering devices from smartphones to electric vehicles and supporting grid-scale energy storage.To ensure their safety and efficiency,batteries must be evaluated under diverse operating conditions.Traditional modeling techniques,which often rely on first principles and atomic-level calculations,struggle with practical applications due to incomplete or noisy data.Furthermore,the complexity of battery dynamics,shaped by physical,chemical,and electrochemical interactions,presents substantial challenges for precise and efficient modeling.The Transformer model,originally designed for natural language processing,has proven effective in time-series analysis and forecasting.It adeptly handles the extensive,complex datasets produced during battery cycles,efficiently filtering out noise and identifying critical features without extensive preprocessing.This capability positions Transformers as potent tools for tackling the intricacies of battery data.This review explores the application of customized Transformers in battery state estimation,emphasizing crucial aspects such as charging,health assessment,lifetime prediction,and safety monitoring.It highlights the distinct advantages of Transformer-based models and addresses ongoing challenges and future opportunities in the field.By combining data-driven AI techniques with empirical insights from battery analysis,these pre-trained models can deliver precise diagnostics and comprehensive monitoring,enhancing performance metrics like health monitoring,anomaly detection,and early-warning systems.This integrated approach promises significant improvements in battery technology management and application.展开更多
With the rapid development of virtual reality(VR)and augmented reality(AR)technologies,their application potential in the field of education has become increasingly significant.For a long time,fire safety education in...With the rapid development of virtual reality(VR)and augmented reality(AR)technologies,their application potential in the field of education has become increasingly significant.For a long time,fire safety education in university laboratories has faced numerous challenges,and traditional teaching methods have been insufficiently effective,with high-risk scenarios difficult to realistically recreate.Especially in special scenarios involving hazardous chemicals,conventional training methods struggle to enable learners to achieve deep understanding and behavioral formation.This study systematically integrates immersive technology theory with safety education needs,providing a replicable technical solution for safety education in high-risk environments.Its modular design approach has reference value for expansion into other professional fields,offering practical evidence for innovation in safety education models in the digital age.展开更多
The present study introduces a screw-pressing charging method to tackle deficiencies in automation and charge uniformity during the melt-casting of polymer-based energetic materials.To ensure the safety of the experim...The present study introduces a screw-pressing charging method to tackle deficiencies in automation and charge uniformity during the melt-casting of polymer-based energetic materials.To ensure the safety of the experiments,this study used inert materials with similar physical properties to partially substitute for the actual energetic components in the preparation of simulant materials.By thoroughly analyzing slurry physical properties,a simulation framework and an extensive performance evaluation method were developed.Such tools guide the design of the structure and configuration of process parameters.Results demonstrate that employing the Pin element significantly enhances radial mixing within the screw,minimizes temperature variations in the slurry,and improves both efficiency and safety in the mixing process.Further,adjustments such as widening the cone angle of the barrel,modifying the solid content of the slurry,and varying the speed of the screw can optimize the mechanical and thermal coupling in the flow field.These adjustments promote higher-quality slurry and create a safer production environment for the extrusion process.展开更多
Due to batteries inconsistencies and potential faults in battery management systems,slight overcharging remains a common yet insufficiently understood safety risk,lacking effective warning methods.To illuminate the de...Due to batteries inconsistencies and potential faults in battery management systems,slight overcharging remains a common yet insufficiently understood safety risk,lacking effective warning methods.To illuminate the degradation behavior and failure mechanism of various overcharged states(100%SOC,105%SOC,110%SOC,and 115%SOC),multiple advanced in-situ characterization techniques(accelerating rate calorimeter,electrochemical impedance spectroscopy,ultrasonic scanning,and expansion instrument)were utilized.Additionally,re-overcharge-induced thermal runaway(TR)tests were conducted,with a specific emphasis on the evolution of the expansion force signal.Results indicated significant degradation at 110%SOC including conductivity loss,loss of lithium inventory,and loss of active material accompanied by internal gas generation.These failure behaviors slow down the expansion force rate during reovercharging,reducing the efficacy of active warnings that depend on rate thresholds of expansion force.Specifically,the warning time for 115%SOC battery is only 144 s,which is 740 s shorter than that for fresh battery,and the time to TR is advanced by 9 min.Moreover,the initial self-heating temperature(T1)is reduced by 62.4℃compared to that of fresh battery,reaching only 70.8℃.To address the low safety of overcharged batteries,a passive overcharge warning method utilizing relaxation expansion force was proposed,based on the continued gas generation after stopping charging,leading to a sustained increase in force.Compared to active methods that rely on thresholds of expansion force rate,the passive method can issue warnings 115 s earlier.By combining the passive and active warning methods,guaranteed effective overcharge warning can be issued 863-884 s before TR.This study introduces a novel perspective for enhancing the safety of batteries.展开更多
BACKGROUND Currently,very few studies have examined the analgesic effectiveness and safety of dexmedetomidine-assisted intravenous-inhalation combined general anesthesia in laparoscopic minimally invasive surgery for ...BACKGROUND Currently,very few studies have examined the analgesic effectiveness and safety of dexmedetomidine-assisted intravenous-inhalation combined general anesthesia in laparoscopic minimally invasive surgery for inguinal hernia.AIM To investigate the analgesic effect and safety of dexmedetomidine-assisted intravenous-inhalation combined general anesthesia in laparoscopic minimally invasive surgery for inguinal hernia.METHODS In this retrospective study,94 patients scheduled for laparoscopic minimally invasive surgery for inguinal hernia,admitted to Yiwu Central Hospital between May 2022 and May 2023,were divided into a control group(inhalation combined general anesthesia)and a treatment group(dexmedetomidine-assisted intrave-nous-inhalation combined general anesthesia).Perioperative indicators,analgesic effect,preoperative and postoperative 24-hours blood pressure(BP)and heart rate(HR),stress indicators,immune function levels,and adverse reactions were com-pared between the two groups.RESULTS Baseline data,including age,hernia location,place of residence,weight,monthly income,education level,and underlying diseases,were not significantly different between the two groups,indicating comparability(P>0.05).No significant difference was found in operation time and anesthesia time between the two groups(P>0.05).However,the treatment group exhibited a shorter postoperative urinary catheter removal time and hospital stay than the control group(P<0.05).Preoperatively,no significant differences were found in the visual analog scale(VAS)scores between the two groups(P>0.05).However,at 12,18,and 24 hours postoper-atively,the treatment group had significantly lower VAS scores than the control group(P<0.05).Although no significant differences in preoperative hemodynamic indicators were found between the two groups(P>0.05),both groups experienced some extent of changes in postoperative HR,diastolic BP(DBP),and systolic BP(SBP).Nevertheless,the treatment group showed smaller changes in HR,DBP,and SBP than the control group(P<0.05).Preoperative immune function indicators showed no significant differences between the two groups(P>0.05).However,postoperatively,the treatment group demonstrated higher levels of CD3+,CD4+,and CD4+/CD8+and lower levels of CD8+than the control group(P<0.05).The rates of adverse reactions were 6.38%and 23.40%in the treatment and control groups,respectively,revealing a significant difference(χ2=5.371,P=0.020).CONCLUSION Dexmedetomidine-assisted intravenous-inhalation combined general anesthesia can promote early recovery of patients undergoing laparoscopic minimally invasive surgery for inguinal hernia.It ensures stable blood flow,improves postoperative analgesic effects,reduces postoperative pain intensity,alleviates stress response,improves immune function,facilitates anesthesia recovery,and enhances safety.展开更多
Strong surface impact will produce strong vibration,which will pose a threat to the safety of nearby buried pipelines and other important lifeline projects.Based on the verified numerical method,a comprehensive numeri...Strong surface impact will produce strong vibration,which will pose a threat to the safety of nearby buried pipelines and other important lifeline projects.Based on the verified numerical method,a comprehensive numerical parameter analysis is conducted on the key influencing factors of the vibration isolation hole(VIH),which include hole diameter,hole net spacing,hole depth,hole number,hole arrangement,and soil parameters.The results indicate that a smaller ratio of net spacing to hole diameter,the deeper the hole,the multi-row hole,the hole adoption of staggered arrangements,and better site soil conditions can enhance the efficiency of the VIH barrier.The average maximum vibration reduction efficiency within the vibration isolation area can reach 42.2%.The vibration safety of adjacent oil pipelines during a dynamic compaction projection was evaluated according to existing standards,and the measurement of the VIH was recommended to reduce excessive vibration.The single-row vibration isolation scheme and three-row staggered arrangement with the same hole parameters are suggested according to different cases.The research findings can serve as a reference for the vibration safety analysis,assessment,and control of adjacent underground facilities under the influence of strong surface impact loads.展开更多
目的:探讨基于年龄、体质指数、进食情况、体重减少情况的营养风险评估工具(Assessment of Nutritional Risk based on BodyMass Index,Intake and Weight loss,AIWW)和营养风险筛查2002(NRS2002)用于胃癌住院病人营养风险筛查的效果,...目的:探讨基于年龄、体质指数、进食情况、体重减少情况的营养风险评估工具(Assessment of Nutritional Risk based on BodyMass Index,Intake and Weight loss,AIWW)和营养风险筛查2002(NRS2002)用于胃癌住院病人营养风险筛查的效果,分析其在胃癌病人中的适用性。方法:采用便利抽样法,选取2023年10月—2024年4月在广西某三级甲等肿瘤医院胃及腹部肿瘤病区就诊的376例胃癌病人,于病人入院后24 h内用AIWW和NRS2002进行营养筛查,以改良版病人主观整体评估(MPG-SGA)评估结果为营养不良的诊断标准,计算AIWW和NRS2002的灵敏度、特异度、阳性预测值和阴性预测值、阳性似然比和阴性似然比、Kappa值以及受试者特征(ROC)曲线和曲线下面积。结果:共纳入376例胃癌病人,以MPG-SGA为诊断标准,254例(67.6%)病人出现营养不良;使用AIWW、NRS2002诊断胃癌病人营养不良风险分别为67.0%、34.8%。AIWW、NRS2002诊断营养不良的灵敏度分别为0.98,0.51,特异度分别为0.97,0.98;AIWW和NRS2002与MPG-SGA的Kappa一致性结果分别为0.928,0.389;ROC曲线下面积分别为0.982,0.788。结论:AIWW、NRS2002均能为胃癌病人营养不良风险筛查提供依据,且两种工具的一致性较好。诊断效能评价中,AIWW灵敏度较高,与MPG-SGA的一致性较好,且条目简单易于评估。因此,建议使用AIWW于胃癌病人的营养筛查。展开更多
The construction of the new tunnel under the existing railway will break the original stress balance in the engineering area, resulting in the secondary redistribution of surrounding rock stress. The large amount of e...The construction of the new tunnel under the existing railway will break the original stress balance in the engineering area, resulting in the secondary redistribution of surrounding rock stress. The large amount of excavation unloading of the soil below is also easy to induce the uneven settlement deformation of the existing structure above, affecting the safety of driving. Based on the shield tunnel project between Caoqiao Station and Lize Business District Station of Beijing Metro, this paper restores the construction site by constructing the finite element numerical model of the project area, calculates and analyzes the deformation and stress of the existing railway structure before and after the construction of the tunnel, and determines the safety impact of the new structure on the existing railway. The results show that the shield tunnel undercrossing construction will cause the “concave” settlement of the railway subgrade above. Under the condition of grouting reinforcement, the “concave” settlement curve is slower and the distribution range is wider. With the advancement of the construction step, the settlement deformation of the subgrade gradually increases. When the tunnel approaches and passes directly below the subgrade, the settlement deformation curve of the subgrade changes from slow to steep. After the tunnel passes away, the curve changes from steep to slow, and the deformation of the subgrade reaches the maximum after the tunnel is connected. Under the grouting condition, the maximum settlement deformation of the subgrade is 2.08 mm, which is about 45% of the settlement deformation of the subgrade under the non-grouting condition. The ground grouting reinforcement can effectively control the subgrade settlement, and the field monitoring verifies the rationality of the calculation results. After the tunnel passes underneath, the most unfavorable section of the existing railway frame bridge is located at the top plate of the structure, and the maximum crack width is 0.178 mm. After grouting reinforcement, the stress environment of the structure is improved, the crack width generated by the structure is smaller, the reinforcement area required for calculation is less, and the structural safety meets the requirements.展开更多
Objective:In recent years,the incidence and detection rate of pancreatic cystic lesions(PCLs)have increased significantly.Endoscopic ultrasound(EUS)plays an indispensable role in the diagnosis and differential diagnos...Objective:In recent years,the incidence and detection rate of pancreatic cystic lesions(PCLs)have increased significantly.Endoscopic ultrasound(EUS)plays an indispensable role in the diagnosis and differential diagnosis of PCLs.However,evidence comparing the diagnostic performance of EUS-guided fine-needle aspiration(EUS-FNA)and fine-needle biopsy(FNB)remains limited.This study aims to compare the diagnostic yield,adequacy of tissue acquisition,and safety between EUS-FNA and EUS-FNB in evaluating PCLs to inform clinical practice.Methods:A retrospective review was conducted on patients with PCLs who underwent either EUS-FNA or EUS-FNB between January 2014 and August 2021.The diagnostic yield,tissue acquisition adequacy,and incidence of adverse events were compared between the 2 groups.Results:A total of 90 patients with PCLs were included(52 in the FNA group and 38 in the FNB group).The diagnostic yield was similar between the FNA and FNB groups(94.2%vs 94.7%,P>0.05).The adequacy of tissue acquisition was 71.2%in the FNA group and 81.6%in the FNB group(P>0.05).No statistically significant difference was observed in the incidence of adverse events between the 2 groups(P>0.05).Conclusion:Both EUS-FNA and EUS-FNB demonstrate equally high diagnostic yields and tissue adequacy in PCLs,with excellent safety profiles.Both methods are safe and effective diagnostic tools for evaluating PCLs.展开更多
文摘To ensure the safe transportation of radioactive materials,numerous countries have established specific standards.For the transfer of fissile materials,it is imperative that the material within the packaging remains in a subcritical state during routine,normal,and accidental transport conditions.In the event of an accident,the rods within the storage tank may become rearranged,introducing uncertainty that must be accounted for to ensure that criticality analysis results are conservative.Historically,this uncertainty was addressed overly conservatively due to limited research on non-uniform arrangement scenarios,which proved unsuitable for criticality safety analysis of spent fuel packages.This paper introduced three distinct methods to non-uniformly rearrange fuel rods—Uniform Arrangement by Blocks,Layer-by-Layer Determination,and Birdcage Deformation—and meticulously evaluates the influences of rod rearrangement on the effective multiplication factor of neutrons,k eff,utilizing the Monte Carlo method.Ultimately,this study presents a holistic method capable of encompassing the entire spectrum of potential effects stemming from the rearrangement of fuel rods during rods mispositioning accident.By augmenting the safety margin,this approach proves to be adeptly suited for the criticality safety analysis of nuclear fuel transport containers.
文摘Background:While the treatment of metastatic renal cell carcinoma(mRCC)is evolving due to immune checkpoint inhibitors(ICIs),optimal strategies for later lines of therapy have yet to be defined.The combination of lenvatinib and everolimus represents a viable option,and the present review aimed to summarize its activity,effectiveness,and safety.Methods:A systematic review of the literature was conducted using PubMed,targeting studies published between 2018 and 2025.Eligible studies included English-language prospective and retrospective trials reporting survival outcomes in mRCC patients treated with lenvatinib and everolimus after at least one ICI-containing regimen.Results:Nine studies met the inclusion criteria,encompassing a total of 441 patients.The lenvatinib and everolimus combination was primarily used in the third and subsequent lines of therapy.Median overall survival ranged from 7.5 to 24.5 months,while median progression-free survival was more consistent,between 6.1 and 6.7 months,except for one study reporting 12.9 months.Objective response rates varied widely(14.0%–55.7%).Adverse events of grade≥3 did not exceed the expected rate,with diarrhoea and proteinuria as the most reported events.Dose reductions and treatment discontinuations due to toxicity occurred but were generally lower than in prior pivotal trials.Conclusions:Real-world evidence suggests that lenvatinib and everolimus represent an effective and safe option after ICI failure in mRCC patients.Nevertheless,the lack of randomized phase III trials and the heterogeneity of existing studies highlight the need for more robust prospective research to guide post-ICI therapeutic strategies.
基金supported by the Medicine-Engineering Interdisciplinary Project of Sun Yat-sen Memorial Hospital,China,No.YXYGRH202203(to YW)Key-Area Research and Development Program of Guangdong Province,China,No.2023B1111050003(to HC)Guangzhou Science and Technology Talent Project of China,No.201909020006(to HC).
文摘Intrathecal administration of human umbilical cord mesenchymal stem cells may be a promising approach for the treatment of stroke,but its safety,effectiveness,and mechanism remain to be elucidated.In this study,good manufacturing practice-grade human umbilical cord mesenchymal stem cells(5×105 and 1×106 cells)and saline were administered by cerebellomedullary cistern injection 72 hours after stroke induced by middle cerebral artery occlusion in rats.The results showed(1)no significant difference in mortality or general conditions among the three groups.There was no abnormal differentiation or tumor formation in various organs of rats in any group.(2)Compared with saline-treated animals,those treated with human umbilical cord mesenchymal stem cells showed significant functional recovery and reduced infarct volume,with no significant differences between different human umbilical cord mesenchymal stem cell doses.(3)Human umbilical cord mesenchymal stem cells were found in the ischemic brain after 14 and 28 days of follow-up,and the number of positive cells significantly decreased over time.(4)Neuronal nuclei expression in the human umbilical cord mesenchymal stem cell group was greater than that in the saline group,while glial fibrillary acidic protein and ionized calcium binding adaptor molecule 1 expression levels decreased.(5)Human umbilical cord mesenchymal stem cell treatment increased the number of CD31+microvessels and doublecortin-positive cells after ischemic stroke.Human umbilical cord mesenchymal stem cells also upregulated the expression of CD31+/Ki67+.(6)At 14 days after intrathecal administration,brain-derived neurotrophic factor expression in the peri-infarct area and the concentrations of brain-derived neurotrophic factor in the cerebrospinal fluid in both human umbilical cord mesenchymal stem cell groups were significantly greater than those in the saline group and persisted until the 28th day.Taken together,these results indicate that the intrathecal administration of human umbilical cord mesenchymal stem cells via cerebellomedullary cistern injection is safe and effective for the treatment of ischemic stroke in rats.The mechanisms may include alleviating the local inflammatory response in the peri-infarct region,promoting neurogenesis and angiogenesis,and enhancing the production of neurotrophic factors.
基金supported by the National Key R&D Program of China under Grant No.2022YFB3103500the National Natural Science Foundation of China under Grants No.62402087 and No.62020106013+3 种基金the Sichuan Science and Technology Program under Grant No.2023ZYD0142the Chengdu Science and Technology Program under Grant No.2023-XT00-00002-GXthe Fundamental Research Funds for Chinese Central Universities under Grants No.ZYGX2020ZB027 and No.Y030232063003002the Postdoctoral Innovation Talents Support Program under Grant No.BX20230060.
文摘The integration of artificial intelligence(AI)technology,particularly large language models(LLMs),has become essential across various sectors due to their advanced language comprehension and generation capabilities.Despite their transformative impact in fields such as machine translation and intelligent dialogue systems,LLMs face significant challenges.These challenges include safety,security,and privacy concerns that undermine their trustworthiness and effectiveness,such as hallucinations,backdoor attacks,and privacy leakage.Previous works often conflated safety issues with security concerns.In contrast,our study provides clearer and more reasonable definitions for safety,security,and privacy within the context of LLMs.Building on these definitions,we provide a comprehensive overview of the vulnerabilities and defense mechanisms related to safety,security,and privacy in LLMs.Additionally,we explore the unique research challenges posed by LLMs and suggest potential avenues for future research,aiming to enhance the robustness and reliability of LLMs in the face of emerging threats.
基金supported by the National Natural Science Foundation of China(72225012)the National Key Research and Development Program of China(2023YFB4302901)+1 种基金the National Natural Science Foundation of China(72288101,71822101,and 62201577)the Safety Capability Building Fund of the Civil Aviation Administration of China(ASSA2023/19).
文摘With the anticipated growth in air traffic complexity in the coming years,future civil aviation transportation system(CATS)is transforming into a complex cyber–physical–social system,surpassing all previous experiences in the history of civil aviation safety management.Therefore,a new safety concept based on a system-of-systems(SoS)perspective is proposed for the next-generation aviation.This article begins by elucidating the complexity of existing aviation risks and emphasizing the necessity for an updated safety concept.It then presents the challenges of current safety management and potential solutions from the new SoS perspective.To address future risks,the concept of SoS safety is introduced with the inspiration of the human immune system in terms of capability,logic,and architecture,which can serve as a guiding framework and methodology for safety engineering in complex large-scale CATS.This concept indicates the transition from“process and outcome-oriented”to“capability-oriented”intelligent safety management.Our research highlights the development directions and potential technological areas that need to be addressed at different stages of SoS safety.The integration of SoS design and operation through rapid iterations enabled by artificial intelligence(AI)will ultimately achieve endogenous SoS safety.
基金supported by the National Natural Science Foundation of China(Grant No.22005275).
文摘Surface engineering plays a crucial role in improving the performance of high energy materials,and polydopamine(PDA)is widely used in the field of energetic materials for surface modification and functionalization.In order to obtain high-quality HMX@PDA-based PBX explosives with high sphericity and a narrow particle size distribution,composite microspheres were prepared using co-axial droplet microfluidic technology.The formation mechanism,thermal behavior,mechanical sensitivity,electrostatic spark sensitivity,compressive strength,and combustion performance of the microspheres were investigated.The results show that PDA can effectively enhance the interfacial interaction between the explosive particles and the binder under the synergistic effect of chemical bonds and the physical"mechanical interlocking"structure.Interface reinforcement causes the thermal decomposition temperature of the sample microspheres to move to a higher temperature,with the sensitivity to impact,friction,and electrostatic sparks(for S-1)increasing by 12.5%,31.3%,and 81.5%respectively,and the compressive strength also increased by 30.7%,effectively enhancing the safety performance of the microspheres.Therefore,this study provides an effective and universal strategy for preparing high-quality functional explosives,and also provides some reference for the safe use of energetic materials in practical applications.
基金the support provided by the California Department of Transportation(Caltrans)through the Fiscal Year 2023-24 grant(65A0686)for the research project titled‘Revolutions in Battery technologies and Future Electric Vehicles’。
文摘Battery technology plays a crucial role across various sectors,powering devices from smartphones to electric vehicles and supporting grid-scale energy storage.To ensure their safety and efficiency,batteries must be evaluated under diverse operating conditions.Traditional modeling techniques,which often rely on first principles and atomic-level calculations,struggle with practical applications due to incomplete or noisy data.Furthermore,the complexity of battery dynamics,shaped by physical,chemical,and electrochemical interactions,presents substantial challenges for precise and efficient modeling.The Transformer model,originally designed for natural language processing,has proven effective in time-series analysis and forecasting.It adeptly handles the extensive,complex datasets produced during battery cycles,efficiently filtering out noise and identifying critical features without extensive preprocessing.This capability positions Transformers as potent tools for tackling the intricacies of battery data.This review explores the application of customized Transformers in battery state estimation,emphasizing crucial aspects such as charging,health assessment,lifetime prediction,and safety monitoring.It highlights the distinct advantages of Transformer-based models and addresses ongoing challenges and future opportunities in the field.By combining data-driven AI techniques with empirical insights from battery analysis,these pre-trained models can deliver precise diagnostics and comprehensive monitoring,enhancing performance metrics like health monitoring,anomaly detection,and early-warning systems.This integrated approach promises significant improvements in battery technology management and application.
文摘With the rapid development of virtual reality(VR)and augmented reality(AR)technologies,their application potential in the field of education has become increasingly significant.For a long time,fire safety education in university laboratories has faced numerous challenges,and traditional teaching methods have been insufficiently effective,with high-risk scenarios difficult to realistically recreate.Especially in special scenarios involving hazardous chemicals,conventional training methods struggle to enable learners to achieve deep understanding and behavioral formation.This study systematically integrates immersive technology theory with safety education needs,providing a replicable technical solution for safety education in high-risk environments.Its modular design approach has reference value for expansion into other professional fields,offering practical evidence for innovation in safety education models in the digital age.
基金financially supported by the Fundamental Research Funds for the Central Universities(Grant No.30923011018)。
文摘The present study introduces a screw-pressing charging method to tackle deficiencies in automation and charge uniformity during the melt-casting of polymer-based energetic materials.To ensure the safety of the experiments,this study used inert materials with similar physical properties to partially substitute for the actual energetic components in the preparation of simulant materials.By thoroughly analyzing slurry physical properties,a simulation framework and an extensive performance evaluation method were developed.Such tools guide the design of the structure and configuration of process parameters.Results demonstrate that employing the Pin element significantly enhances radial mixing within the screw,minimizes temperature variations in the slurry,and improves both efficiency and safety in the mixing process.Further,adjustments such as widening the cone angle of the barrel,modifying the solid content of the slurry,and varying the speed of the screw can optimize the mechanical and thermal coupling in the flow field.These adjustments promote higher-quality slurry and create a safer production environment for the extrusion process.
基金supported by the National Natural Science Foundation of China(52476200,52106244)the Guangdong Basic and Applied Basic Research Foundation(2024A1515030124)+1 种基金the Science and Technology Project of China Southern Power Grid under Grant GDKJXM20230246(030100KC23020017)the Fundamental Research Funds for the Central Universities。
文摘Due to batteries inconsistencies and potential faults in battery management systems,slight overcharging remains a common yet insufficiently understood safety risk,lacking effective warning methods.To illuminate the degradation behavior and failure mechanism of various overcharged states(100%SOC,105%SOC,110%SOC,and 115%SOC),multiple advanced in-situ characterization techniques(accelerating rate calorimeter,electrochemical impedance spectroscopy,ultrasonic scanning,and expansion instrument)were utilized.Additionally,re-overcharge-induced thermal runaway(TR)tests were conducted,with a specific emphasis on the evolution of the expansion force signal.Results indicated significant degradation at 110%SOC including conductivity loss,loss of lithium inventory,and loss of active material accompanied by internal gas generation.These failure behaviors slow down the expansion force rate during reovercharging,reducing the efficacy of active warnings that depend on rate thresholds of expansion force.Specifically,the warning time for 115%SOC battery is only 144 s,which is 740 s shorter than that for fresh battery,and the time to TR is advanced by 9 min.Moreover,the initial self-heating temperature(T1)is reduced by 62.4℃compared to that of fresh battery,reaching only 70.8℃.To address the low safety of overcharged batteries,a passive overcharge warning method utilizing relaxation expansion force was proposed,based on the continued gas generation after stopping charging,leading to a sustained increase in force.Compared to active methods that rely on thresholds of expansion force rate,the passive method can issue warnings 115 s earlier.By combining the passive and active warning methods,guaranteed effective overcharge warning can be issued 863-884 s before TR.This study introduces a novel perspective for enhancing the safety of batteries.
文摘BACKGROUND Currently,very few studies have examined the analgesic effectiveness and safety of dexmedetomidine-assisted intravenous-inhalation combined general anesthesia in laparoscopic minimally invasive surgery for inguinal hernia.AIM To investigate the analgesic effect and safety of dexmedetomidine-assisted intravenous-inhalation combined general anesthesia in laparoscopic minimally invasive surgery for inguinal hernia.METHODS In this retrospective study,94 patients scheduled for laparoscopic minimally invasive surgery for inguinal hernia,admitted to Yiwu Central Hospital between May 2022 and May 2023,were divided into a control group(inhalation combined general anesthesia)and a treatment group(dexmedetomidine-assisted intrave-nous-inhalation combined general anesthesia).Perioperative indicators,analgesic effect,preoperative and postoperative 24-hours blood pressure(BP)and heart rate(HR),stress indicators,immune function levels,and adverse reactions were com-pared between the two groups.RESULTS Baseline data,including age,hernia location,place of residence,weight,monthly income,education level,and underlying diseases,were not significantly different between the two groups,indicating comparability(P>0.05).No significant difference was found in operation time and anesthesia time between the two groups(P>0.05).However,the treatment group exhibited a shorter postoperative urinary catheter removal time and hospital stay than the control group(P<0.05).Preoperatively,no significant differences were found in the visual analog scale(VAS)scores between the two groups(P>0.05).However,at 12,18,and 24 hours postoper-atively,the treatment group had significantly lower VAS scores than the control group(P<0.05).Although no significant differences in preoperative hemodynamic indicators were found between the two groups(P>0.05),both groups experienced some extent of changes in postoperative HR,diastolic BP(DBP),and systolic BP(SBP).Nevertheless,the treatment group showed smaller changes in HR,DBP,and SBP than the control group(P<0.05).Preoperative immune function indicators showed no significant differences between the two groups(P>0.05).However,postoperatively,the treatment group demonstrated higher levels of CD3+,CD4+,and CD4+/CD8+and lower levels of CD8+than the control group(P<0.05).The rates of adverse reactions were 6.38%and 23.40%in the treatment and control groups,respectively,revealing a significant difference(χ2=5.371,P=0.020).CONCLUSION Dexmedetomidine-assisted intravenous-inhalation combined general anesthesia can promote early recovery of patients undergoing laparoscopic minimally invasive surgery for inguinal hernia.It ensures stable blood flow,improves postoperative analgesic effects,reduces postoperative pain intensity,alleviates stress response,improves immune function,facilitates anesthesia recovery,and enhances safety.
基金National Natural Science Foundation of China under Grant Nos.52078386 and 52308496SINOMACH Youth Science and Technology Fund under Grant No.QNJJ-PY-2022-02+2 种基金Young Elite Scientists Sponsorship Program under Grant No.BYESS2023432Fund of State Key Laboratory of Precision Blasting and Hubei Key Laboratory of Blasting Engineering,Jianghan University under Grant No.PBSKL2023A9Fund of China Railway Construction Group Co.,Ltd.under Grant No.LX19-04b。
文摘Strong surface impact will produce strong vibration,which will pose a threat to the safety of nearby buried pipelines and other important lifeline projects.Based on the verified numerical method,a comprehensive numerical parameter analysis is conducted on the key influencing factors of the vibration isolation hole(VIH),which include hole diameter,hole net spacing,hole depth,hole number,hole arrangement,and soil parameters.The results indicate that a smaller ratio of net spacing to hole diameter,the deeper the hole,the multi-row hole,the hole adoption of staggered arrangements,and better site soil conditions can enhance the efficiency of the VIH barrier.The average maximum vibration reduction efficiency within the vibration isolation area can reach 42.2%.The vibration safety of adjacent oil pipelines during a dynamic compaction projection was evaluated according to existing standards,and the measurement of the VIH was recommended to reduce excessive vibration.The single-row vibration isolation scheme and three-row staggered arrangement with the same hole parameters are suggested according to different cases.The research findings can serve as a reference for the vibration safety analysis,assessment,and control of adjacent underground facilities under the influence of strong surface impact loads.
文摘目的:探讨基于年龄、体质指数、进食情况、体重减少情况的营养风险评估工具(Assessment of Nutritional Risk based on BodyMass Index,Intake and Weight loss,AIWW)和营养风险筛查2002(NRS2002)用于胃癌住院病人营养风险筛查的效果,分析其在胃癌病人中的适用性。方法:采用便利抽样法,选取2023年10月—2024年4月在广西某三级甲等肿瘤医院胃及腹部肿瘤病区就诊的376例胃癌病人,于病人入院后24 h内用AIWW和NRS2002进行营养筛查,以改良版病人主观整体评估(MPG-SGA)评估结果为营养不良的诊断标准,计算AIWW和NRS2002的灵敏度、特异度、阳性预测值和阴性预测值、阳性似然比和阴性似然比、Kappa值以及受试者特征(ROC)曲线和曲线下面积。结果:共纳入376例胃癌病人,以MPG-SGA为诊断标准,254例(67.6%)病人出现营养不良;使用AIWW、NRS2002诊断胃癌病人营养不良风险分别为67.0%、34.8%。AIWW、NRS2002诊断营养不良的灵敏度分别为0.98,0.51,特异度分别为0.97,0.98;AIWW和NRS2002与MPG-SGA的Kappa一致性结果分别为0.928,0.389;ROC曲线下面积分别为0.982,0.788。结论:AIWW、NRS2002均能为胃癌病人营养不良风险筛查提供依据,且两种工具的一致性较好。诊断效能评价中,AIWW灵敏度较高,与MPG-SGA的一致性较好,且条目简单易于评估。因此,建议使用AIWW于胃癌病人的营养筛查。
文摘The construction of the new tunnel under the existing railway will break the original stress balance in the engineering area, resulting in the secondary redistribution of surrounding rock stress. The large amount of excavation unloading of the soil below is also easy to induce the uneven settlement deformation of the existing structure above, affecting the safety of driving. Based on the shield tunnel project between Caoqiao Station and Lize Business District Station of Beijing Metro, this paper restores the construction site by constructing the finite element numerical model of the project area, calculates and analyzes the deformation and stress of the existing railway structure before and after the construction of the tunnel, and determines the safety impact of the new structure on the existing railway. The results show that the shield tunnel undercrossing construction will cause the “concave” settlement of the railway subgrade above. Under the condition of grouting reinforcement, the “concave” settlement curve is slower and the distribution range is wider. With the advancement of the construction step, the settlement deformation of the subgrade gradually increases. When the tunnel approaches and passes directly below the subgrade, the settlement deformation curve of the subgrade changes from slow to steep. After the tunnel passes away, the curve changes from steep to slow, and the deformation of the subgrade reaches the maximum after the tunnel is connected. Under the grouting condition, the maximum settlement deformation of the subgrade is 2.08 mm, which is about 45% of the settlement deformation of the subgrade under the non-grouting condition. The ground grouting reinforcement can effectively control the subgrade settlement, and the field monitoring verifies the rationality of the calculation results. After the tunnel passes underneath, the most unfavorable section of the existing railway frame bridge is located at the top plate of the structure, and the maximum crack width is 0.178 mm. After grouting reinforcement, the stress environment of the structure is improved, the crack width generated by the structure is smaller, the reinforcement area required for calculation is less, and the structural safety meets the requirements.
基金supported by the Special Project for the Construction of Innovative Provinces in Hunan Province,China(2020SK2013)。
文摘Objective:In recent years,the incidence and detection rate of pancreatic cystic lesions(PCLs)have increased significantly.Endoscopic ultrasound(EUS)plays an indispensable role in the diagnosis and differential diagnosis of PCLs.However,evidence comparing the diagnostic performance of EUS-guided fine-needle aspiration(EUS-FNA)and fine-needle biopsy(FNB)remains limited.This study aims to compare the diagnostic yield,adequacy of tissue acquisition,and safety between EUS-FNA and EUS-FNB in evaluating PCLs to inform clinical practice.Methods:A retrospective review was conducted on patients with PCLs who underwent either EUS-FNA or EUS-FNB between January 2014 and August 2021.The diagnostic yield,tissue acquisition adequacy,and incidence of adverse events were compared between the 2 groups.Results:A total of 90 patients with PCLs were included(52 in the FNA group and 38 in the FNB group).The diagnostic yield was similar between the FNA and FNB groups(94.2%vs 94.7%,P>0.05).The adequacy of tissue acquisition was 71.2%in the FNA group and 81.6%in the FNB group(P>0.05).No statistically significant difference was observed in the incidence of adverse events between the 2 groups(P>0.05).Conclusion:Both EUS-FNA and EUS-FNB demonstrate equally high diagnostic yields and tissue adequacy in PCLs,with excellent safety profiles.Both methods are safe and effective diagnostic tools for evaluating PCLs.
