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Formation control for multiple spacecraft with disturbances and sensor failures
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作者 Yufei LYU Yuezu PENG Wenliang 《Journal of Systems Engineering and Electronics》 2026年第1期18-25,共8页
Formation control of multiple spacecraft has attracted extensive research attention.However,achieving reliable performance under sensor failures remains a significant challenge.This paper develops an integrated framew... Formation control of multiple spacecraft has attracted extensive research attention.However,achieving reliable performance under sensor failures remains a significant challenge.This paper develops an integrated framework that jointly designs distributed observers and local controllers to ensure robust formation control in the presence of external disturbances and sensor malfunctions.Treating the spacecraft formation as a single interconnected system,each spacecraft constructs a distributed observer that estimates the overall system state by incorporating both its own measurements and the predicted control information shared among the spacecraft.Based on the observer estimates,a local control law is synthesized to maintain the desired formation.Rigorous theoretical analysis and numerical simulations demonstrate that the proposed integrated approach effectively guarantees formation stability and resilience against sensor failures and disturbances. 展开更多
关键词 formation control multiple spacecraft DISTURBANCE sensor failure
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Effect of insomnia on anxiety and depression:Mediation of cognitive failures and moderated mediation of neuroticism
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作者 Yue Li Jia-Long Yu +3 位作者 Shu-Yi Wang Lu-Xin Xie Jia-Long Hong Sha Liu 《World Journal of Psychiatry》 2025年第2期161-172,共12页
BACKGROUND The coronavirus disease 2019 pandemic has had an ongoing impact on the public’s mental health that requires long-term attention.Exploring the relationship between mental health indicators would aid in iden... BACKGROUND The coronavirus disease 2019 pandemic has had an ongoing impact on the public’s mental health that requires long-term attention.Exploring the relationship between mental health indicators would aid in identifying solutions to improve public mental health.AIM To investigate the prevalence of anxiety,depression,and insomnia and explore the relationship among neuroticism,cognitive failures,and mental health.METHODS A cross-sectional survey was conducted in December 2023 using an online platform to recruit adult participants.The neuroticism,subjective cognitive function,and mental health of the participants were assessed using the neuroticism subscale of the Chinese Big Five Personality Inventory Brief Version,cognitive failures questionnaire,generalized anxiety disorder-7,patient health questionnaire-9,and insomnia severity index.Pearson's correlation analysis,independent samples t-tests,one-way analysis of variance,and structural equation model were used to examine the relationship between mental health indicators.RESULTS A total of 1011 valid questionnaires were collected,of which 343 were completed by male(33.93%)respondents and 668 were completed by female(66.07%)respondents.The rates of anxiety,depression,and insomnia were 41.3%,44.6%,and 36.3%,respectively,most cases of which were mild.Among the mental health indicators,there were significant differences by age and between those with siblings and those who were only children.Neuroticism and cognitive failures were significantly positively correlated with mental health indicators.Further moderated mediation analysis showed that cognitive failures mediated the relationship between insomnia and anxiety and between insomnia and depression,with neuroticism moderating the first half of this pathway and the effect being greater in the low-neuroticism group.CONCLUSION Cognitive failures and neuroticism play important roles in mental health.Therefore,enhancing subjective cognitive function and regulating emotional stability may contribute to the improvement of mental health. 展开更多
关键词 INSOMNIA ANXIETY DEPRESSION NEUROTICISM Cognitive failures
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Multiscale Mechanical Failures in Lithium-Ion Batteries:Experimental and Theoretical Approaches
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作者 Chong Chen Yikun Wu +3 位作者 inbao Fan Zi-Ping Wang Lei Sun Hao-Sen Chen 《Acta Mechanica Solida Sinica》 2025年第3期344-357,共14页
The insertion and extraction of lithium ions in active materials lead to significant volumetric deformation,resulting in stresses that drive the mechanical degradation of these materials.This accumulation of mechanica... The insertion and extraction of lithium ions in active materials lead to significant volumetric deformation,resulting in stresses that drive the mechanical degradation of these materials.This accumulation of mechanical degradation ultimately leads to mechanical failure in lithium-ion batteries(LIB).This paper summarizes the experimental characterization techniques used to observe the mechanical degradation of lithium battery cells,electrodes,and particles across macro,micro,and nano scales.Additionally,the mechanical failure model for LIB that spans from the microscopic to the macroscopic scale has been outlined.Finally,we analyze the current challenges and opportunities,including the standardization of battery measurements,the quantification of mechanical failures,and the correlation between mechanical failures and electrochemical performance. 展开更多
关键词 Mechanical failure Experimental characterization Chemo-mechanical coupling Lithium-ion battery
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Study on Cascading Failures Based on Intra-Layer and Inter-Layer Structures of Multiplayer Networks
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作者 CHEN Mengjiao WANG Niu WEI Daijun 《数学理论与应用》 2025年第3期107-124,共18页
Compared to single-layer networks,multilayer networks exhibit a more complex node degree composition,comprising both intra-layer and inter-layer degrees.However,the distinct impacts of these degree types on cascading ... Compared to single-layer networks,multilayer networks exhibit a more complex node degree composition,comprising both intra-layer and inter-layer degrees.However,the distinct impacts of these degree types on cascading failures remain underexplored.Distinguishing their effects is crucial for a deeper understanding of network structure,information propagation,and behavior prediction.This paper proposes a capacity-load model to influence and compare the influence of different degree types on cascading failures in multilayer networks.By designing three node removal strategies based on total degree,intra-layer degree,and inter-layer degree,simulation experiments are conducted on four types of networks.Network robustness is evaluated using the maximum number of removable nodes before collapse.The relationships between network robustness and the coupling coefficient,as well as load and capacity adjustment parameters,are also analyzed.The results indicate that the node removal strategy with the least impact on cascading failures varies across different types of networks,revealing the significance of different node degrees in failure propagation.Compared to other models,the proposed model enables networks to maintain a higher maximum number of removable nodes during cascading failures,demonstrating superior robustness. 展开更多
关键词 Multilayer network ROBUSTNESS Cascading failure Capacity load model
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Frequent Pattern Growth-Based Identification of Critical Lines in Cascading Failures for Renewable-Dominant Hybrid AC/DC Power Systems
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作者 Tianhao Liu Jiongcheng Yan Yutian Liu 《Engineering》 2025年第8期158-170,共13页
In wind and solar renewable-dominant hybrid alternating current/direct current(AC/DC)power systems,the active power of high-voltage direct current(HVDC)system is significantly limited by the security and stability eve... In wind and solar renewable-dominant hybrid alternating current/direct current(AC/DC)power systems,the active power of high-voltage direct current(HVDC)system is significantly limited by the security and stability events caused by cascading failures.To identify critical lines in cascading failures,a rapid risk assessment method is proposed based on the gradient boosting decision tree(GBDT)and frequent pat-tern growth(FP-Growth)algorithms.First,security and stability events triggered by cascading failures are analyzed to explain the impact of cascading failures on the maximum DC power.Then,a cascading failure risk index is defined,focusing on the DC power being limited.To handle the strong nonlinear relationship between the maximum DC power and cascading failures,a GBDT with an update strategy is utilized to rapidly predict the maximum DC power under uncertain operating conditions.Finally,the FP-Growth algorithm is improved to mine frequent patterns in cascading failures.The importance index for each fault in a frequent pattern is defined by evaluating its impact on cascading failures,enabling the identification of critical lines.Simulation results of a modified Ningxia–Shandong hybrid AC/DC system in China demonstrate that the proposed method can rapidly assess the risk of cascading failures and effectively identify critical lines. 展开更多
关键词 Cascading failure Risk assessment Frequent pattern Hybrid AC/DC power system Renewable energy
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Audit Without Integrity:Ethical Failures and Fraud in High-Profile Corporate Cases
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作者 Enda Putri Rudangta Meliala Julia +1 位作者 Iskandar Muda Erlina 《Journal of Modern Accounting and Auditing》 2025年第3期218-228,共11页
This study explores ethical violations and audit failures in various large-scale corporate fraud cases.Using a qualitative descriptive method and based on secondary data from documented fraud cases and published audit... This study explores ethical violations and audit failures in various large-scale corporate fraud cases.Using a qualitative descriptive method and based on secondary data from documented fraud cases and published audit reports,the study applies the Fraud Triangle framework,focusing on how weak integrity,objectivity,and professional competence have undermined public trust in the auditing profession.Using a qualitative descriptive method and the Fraud Triangle framework,which includes pressure,opportunity,and rationalization,the study analyzes cases from Indonesia(SNP Finance,Jiwasraya),China(Evergrande),and Germany(Wirecard).The analysis reveals that many audit failures observed in this study appear to stem more from ethical challenges than from technical incapability,driven by client pressure,weak internal controls,and compromised auditor independence.These cases demonstrate a recurring global pattern in which auditors neglect their responsibility to act in the public interest. 展开更多
关键词 auditor ethics internal auditor competence internal control fraud triangle audit failure professional responsibility SNP Finance Evergrande Wirecard Jiwasraya
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Audit without Integrity:Ethical Failures and Fraud in High-Profile Corporate Cases
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作者 Enda Putri Rudangta Meliala Julia +1 位作者 Iskandar Muda Erlina 《Journal of Modern Accounting and Auditing》 2025年第3期159-169,共11页
This study explores ethical violations and audit failures in various large-scale corporate fraud cases.Using a qualitative descriptive method and based on secondary data from documented fraud cases and published audit... This study explores ethical violations and audit failures in various large-scale corporate fraud cases.Using a qualitative descriptive method and based on secondary data from documented fraud cases and published audit reports,the study applies the Fraud Triangle framework,focusing on how weak integrity,objectivity,and professional competence have undermined public trust in the auditing profession.Using a qualitative descriptive method and the Fraud Triangle framework,which includes pressure,opportunity,and rationalization,the study analyzes cases from Indonesia(SNP Finance,Jiwasraya),China(Evergrande),and Germany(Wirecard).The analysis reveals that many audit failures observed in this study appear to stem more from ethical challenges than from technical incapability,driven by client pressure,weak internal controls,and compromised auditor independence.These cases demonstrate a recurring global pattern in which auditors neglect their responsibility to act in the public interest. 展开更多
关键词 auditor ethics internal auditor competence internal control fraud triangle audit failure professional responsibility SNP Finance Evergrande Wirecard Jiwasraya
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Sustainable Emergency Rescue Products: Design and Monitoring Techniques for Preventing and Mitigating Construction Failures in Unforeseen Circumstances
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作者 Xiaobo Jiang Hongchao Zheng 《Structural Durability & Health Monitoring》 2025年第6期1695-1716,共22页
Construction failures caused by unforeseen circumstances, such as natural disasters, environmental degradation, and structural weaknesses, present significant challenges in achieving durability, safety, and sustainabi... Construction failures caused by unforeseen circumstances, such as natural disasters, environmental degradation, and structural weaknesses, present significant challenges in achieving durability, safety, and sustainability. This research addresses these challenges through the development of advanced emergency rescue systems incorporating wood-derived nanomaterials and IoT-enabled Structural Health Monitoring (SHM) technologies. The use of nanocellulose which demonstrates outstanding mechanical capabilities and biodegradability alongside high resilience allowed developers to design modular rescue systems that function effectively even under challenging conditions while providing real-time failure protection. Experimental data from testing showed that the replacement system strengthened load-bearing limits by 20% while enhancing impact tolerance by 30% and decreasing lifecycle carbon footprints by 60% against conventional methods. FEA results alongside dynamic simulations established that the system maintains its strength across seismic events and thermal variations and environmental conditions. SHM systems that leverage the Internet of Things Platform revealed 95% accuracy rates in detecting anomalies while improving response speed by 30% for predictive maintenance operations. The innovative solutions support the special issue’s direction to push structural transformation through durable designs and creative materials with preventive failure solutions. The proposed solutions work together toward creating resilient infrastructure systems which resist unexpected stressors and environmental damage. 展开更多
关键词 Sustainable materials wood-derived nanomaterials structural durability emergency rescue products construction failures smart materials structural health monitoring IoT-based monitoring RESILIENCE environmental sustainability
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Transmission patterns of progressive damage and reliability analysis of reservoir-induced landslides considering local tensile failure
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作者 Minghao Miao Huiming Tang +5 位作者 Yinlong Jiang Kun Fang Changdong Li Cheng He Peng Cao Sha Lu 《Journal of Rock Mechanics and Geotechnical Engineering》 2026年第2期913-931,共19页
Reservoir-induced landslides in China's Three Gorges Reservoir area are prone to tensile cracks due to the influenceof their own weight and fluctuationsin water levels.The presence of cracks indicates that the ten... Reservoir-induced landslides in China's Three Gorges Reservoir area are prone to tensile cracks due to the influenceof their own weight and fluctuationsin water levels.The presence of cracks indicates that the tensile stress in the area has exceeded the tensile strength of the soil,leading to local instability.To explore the impact of tensile failure behavior on the stability and failure modes of reservoir landslides,the Huangtupo Riverside Slump#1 is taken as a case study.By considering local tensile failure,potential tensile cracks are incorporated into the analysis via the limit equilibrium method and reliability theory.The reliability of landslides under different tensile failure scenarios is quantified.Strain-softening characteristics of the soil are combined to further analyze the failure transmission path of the landslide.Finally,these potential failure modes were validated through physical model tests.The results show that cracks developing at rear positions reduce the stability of the slope and increase the probability of instability.During the destruction process,retrogressive failures with multiple sliding surfaces are likely to occur.However,tensile failure at the forefront reduces the likelihood of an individual slide mass descending.Progressive failure results in both regular and skip transmission patterns.Additionally,cracks and water level changes can also lead to shifts in the positions of the most dangerous blocks.Therefore,in practical landslide analysis and prevention,it is necessary to consider local tensile damage and identify potential tensile crack locations in advance to optimize prevention measures and accurately evaluate landslide risk. 展开更多
关键词 Reliability analysis Tensile failure Reservoir landslide Progressive damage failure mode Tensile crack
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Utility of the Vulnerable Elders Survey-13(VES-13) in detecting frailty and predicting prognosis in heart failure outpatients
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作者 Thaïs Roig Elisabet Zamora +15 位作者 Josep Lupón Beatriz González Ana Pulido Eva Crespo Patricia Velayos Carmen Rivas Violeta Díaz Yolanda López Andrea Borrellas Mar Domingo María Ruiz Pau Codina Evelyn Santiago-Vacas MiquelÀMas Ramón Miralles Antoni Bayes-Genis 《Journal of Geriatric Cardiology》 2026年第1期17-26,共10页
Background Frailty is common and significantly impacts prognosis in heart failure(HF). The Vulnerable Elders Survey-13(VES-13), widely used in oncogeriatrics and public health, remains unexplored as a frailty screenin... Background Frailty is common and significantly impacts prognosis in heart failure(HF). The Vulnerable Elders Survey-13(VES-13), widely used in oncogeriatrics and public health, remains unexplored as a frailty screening tool in HF outpatients. In this study, we prospectively evaluated VES-13 against a multimodal screening assessment in detecting frailty and predicting individual risk of adverse prognosis.Methods Frailty was assessed at the initial visit using both a multimodal approach, incorporating Barthel Index, Older American Resources and Services scale, Pfeiffer Test, abbreviated Geriatric Depression Scale, age > 85 years, lacking support systems,and VES-13. Patients scoring ≥ 3 on VES-13 or meeting at least one multimodal criterion were classified as frail. Endpoints included all-cause mortality, a composite of death or HF hospitalization, and recurrent HF hospitalizations.Results A total of 301 patients were evaluated. VES-13 identified 40.2% as frail and the multimodal assessment 33.2%. In Cox regression analyses, frailty identified by VES-13 showed greater prognostic significance than the multimodal assessment for allcause mortality(HR = 3.70 [2.15–6.33], P < 0.001 vs. 2.40 [1.46–4.0], P = 0.001) and the composite endpoint(HR = 3.13 [2.02–4.84], P< 0.001 vs. 1.96 [1.28–2.99], P = 0.002). Recurrent HF hospitalizations were four times more frequent in VES-13 frail patients while two times in those identified as frail by the multimodal assessment. Additionally, stratifying patients by VES-13 tertiles provided robust risk differentiation.Conclusions VES-13, a simple frailty tool, outperformed a comprehensive multimodal assessment and could be easily integrated into routine HF care, highlighting its clinical utility in identifying patients at risk for poor outcomes. 展开更多
关键词 barthel i FRAILTY heart failure hf Heart failure multimodal screening assessment multimodal approach detecting frailty Vulnerable Elders Survey
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Decade of insights on causes of scleral buckle failure in retinal detachment
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作者 Hu Cheng Liu Yin +6 位作者 Du Fan Zhu Li Xiang Nian Huang Zhijian Yan Ying Zeng Bo Chen Xiao 《国际眼科杂志》 2026年第2期197-201,共5页
AIM:To investigate the underlying causes of surgical failure and reoperation management in patients with rhegmatogenous retinal detachment(RRD)who underwent scleral buckle surgery at our institution.METHODS:This was a... AIM:To investigate the underlying causes of surgical failure and reoperation management in patients with rhegmatogenous retinal detachment(RRD)who underwent scleral buckle surgery at our institution.METHODS:This was a single-center,retrospective,descriptive study.The clinical data of 368 patients(387 eyes)with RRD who underwent scleral buckling(SB)surgery between August 2013 and July 2023 at our institution were collected.The aim was to analyze the causes of recurrence and the rationale for selecting reoperation methods.RESULTS:Totally 368 patients(387 eyes)were included in the analysis,comprising 222 males and 146 females.The average age was 30.26±14.18 years,and the mean follow-up duration was(48.33±20.39)mo.The success rate of SB surgery was 90.2%.Recurrent retinal detachment occurred in 38 eyes.Based on surgical records,the causes of SB failure were analyzed.The recurrence causes included abnormal compression ridge position(position,height,or width)in 14 eyes(36.8%,14/38),hole omission in 11 eyes(29.0%,11/38),proliferative vitreoretinopathy(PVR)in 10 eyes(26.3%,10/38),and new holes in 3 eyes(7.9%,3/38).Among these,8 eyes(21.1%,8/38)underwent repeat SB surgery,while the remaining 30 eyes(78.9%,30/38)underwent pars plana vitrectomy(PPV).Regarding tamponade agents,silicone oil was used in 11 eyes(36.7%,11/30),C_(3)F_(8) gas in 12 eyes(40.0%,12/30),and sterile air in 7 eyes(23.3%,7/30).CONCLUSION:SB surgery demonstrates a high success rate in the treatment of RRD.However,abnormal compression ridge position,missed holes during surgery,and PVR are the primary causes of SB failure.After addressing the reasons for failure,re-SB surgery or PPV can be effective alternatives. 展开更多
关键词 retinal detachment scleral buckling cause of failure REOPERATION
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Correlation between life satisfaction,pleasure level,and negative emotion in patients with chronic renal failure
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作者 Lin-Lin Zhang You-Li Zhang +3 位作者 Ting Liu Jian Wang Chen Chen Xiao-Yu Wang 《World Journal of Psychiatry》 2026年第1期291-298,共8页
BACKGROUND Anxiety,depression,and other negative emotions are common among patients with chronic renal failure(CRF).Analyzing the factors related to negative emotions is necessary to provide targeted nursing care.AIM ... BACKGROUND Anxiety,depression,and other negative emotions are common among patients with chronic renal failure(CRF).Analyzing the factors related to negative emotions is necessary to provide targeted nursing care.AIM To explore the correlations among life satisfaction,pleasure levels,and negative emotions in patients with CRF.METHODS One hundred patients with CRF who received therapy at the First Affiliated Hospital of Jinzhou Medical University between December 2022 and February 2025 were included.The Depression,Anxiety,and Stress Scale(DASS-21),Satisfaction with Life Scale(SWLS),and Temporal Experience of Pleasure Scale(TEPS)were used to evaluate negative emotions,life satisfaction,and pleasure level,respectively.Pearson’s correlation coefficient analyzed the correlation between life satisfaction,pleasure level,and negative emotions.Linear regression analysis identified the factors affecting negative emotions.RESULTS The average DASS-21 score among patients with CRF was 51.90±2.30,with subscale scores of 17.90±1.50 for depression,18.53±1.18 for anxiety,and 15.47±2.36 for stress,all significantly higher than the domestic norm(P<0.05).The average SWLS score was 22.17±4.90.Correlation analysis revealed a negative correlation between the SWLS and total DASS-21 scores(P<0.05),but not with the individual depression,anxiety,or stress dimensions.The average TEPS score was 67.80±8.34.TEPS scores were negatively correlated with the DASS-21 score and the stress dimension(P<0.05),but not with depression or anxiety.Linear regression analysis showed that TEPS scores significantly influenced DASS-21 scores(P<0.05).CONCLUSION Patients with CRF experience high levels of negative emotions,which are negatively correlated with life satisfaction and pleasure.Furthermore,pleasure level had an impact on negative emotions. 展开更多
关键词 Chronic renal failure HEMODIALYSIS Negative emotion Life satisfaction PLEASURE CORRELATION
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Preterm heart failure and refractory lactic acidosis caused by congenital hypothyroidism:A case report and review of literature
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作者 Hong-Ju Chen Jiao Li +3 位作者 Xiao-Ming Xu Bo Zhang Bo-Chao Cheng Jing Shi 《World Journal of Clinical Cases》 2026年第1期43-51,共9页
BACKGROUND Congenital hypothyroidism(CH)is a common condition in both preterm and term infants characterized by either thyroid gland absence or hypofunctionality.The clinical association of refractory lactic acidosis ... BACKGROUND Congenital hypothyroidism(CH)is a common condition in both preterm and term infants characterized by either thyroid gland absence or hypofunctionality.The clinical association of refractory lactic acidosis and heart failure has rarely been observed in cases of pediatric patients with CH pathology.Here,we explored the etiological relationship between CH,heart failure,and refractory lactic acidosis to reflect the importance of thyroid function screening in neonates with heart disease.CASE SUMMARY A 33-day-old extremely premature female infant presented with tachypnea,respiratory distress,recurrent infections,and abdominal distension postnatal.On admission to our facility,she had cardiomegaly,hepatomegaly,and lactic acidosis(revealed on blood gas analysis),with lactate progressively rising to 25 mmol/L.Chest radiographs showed pulmonary congestion,while echocardiography revealed cardiac enlargement,left ventricular wall thickening,and pericardial effusion.Initial management aimed at correcting acidosis and treating heart failure proved ineffective.After reassessment,thyroid function tests showed significantly decreased triiodothyronine,free triiodothyronine,thyroxine,and free thyroxine levels,with a significantly increased thyroidstimulating hormone level,confirming a CH diagnosis.Levothyroxine was administered,resulting in rapid correction of lactic acidosis and gradual improvement of thyroid function and systemic symptoms,culminating in full recovery and discharge.We also reviewed the relevant literature on thyroid and cardiac dysfunctions in order to explore their deeper association.CONCLUSION This case links CH-induced heart failure with refractory lactic acidosis,urging prompt thyroid screening in affected neonates to reduce mortality. 展开更多
关键词 Congenital hypothyroidism Lactic acidosis Heart failure NEONATE PRETERM Case report
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Effect of dynamic disturbance frequency on brittle failure of granite in deep excavation
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作者 Ben-Guo He Hanyi Liu +1 位作者 Xia-Ting Feng Hongyuan Fu 《Journal of Rock Mechanics and Geotechnical Engineering》 2026年第2期1002-1015,共14页
Dynamic disturbances with various frequencies could trigger different failure modes of deep excavations.Superimposed on this static stress are dynamic disturbances due to various dynamic vibrations,e.g.excavation blas... Dynamic disturbances with various frequencies could trigger different failure modes of deep excavations.Superimposed on this static stress are dynamic disturbances due to various dynamic vibrations,e.g.excavation blasting,blasting,tunnel boring machine(TBM)vibration,rockburst wave,earthquakes.Specifically,these dynamic sources are characterized by a wide range of wave frequencies f,resulting in differences in failure modes.A series of true-triaxial compression tests were conducted on granite to simulate the excavation-induced stress path in three-dimensional(3D)stresses.Subsequently,a dynamic disturbance with various frequencies was applied to a cuboid specimen,to reveal the behavior associated with brittle failure.The dynamic disturbance with frequencies f of 5 Hz,10 Hz,and 40 Hz generates less disturbed energy components in the granite together with higher peak strength.However,dynamic disturbances with f of 20 Hz and 30 Hz resulted in a lower peak strength;the peak strength of the rock increases sp albeit it decreases at first,then increases.This U-shaped phenomenon relates to the natural frequency of the granite under such stress conditions.Different rock lithologies consisting of diverse mineral composition,respond differently to each sensitive resonance frequency.Interestingly,the weak disturbance stress with a high frequency f and low amplitude A increases the ratio of crack damage to peak strength(scd/sp)in the granite.This leads to the inhibition of the expansion of the granite during the dynamic disturbance process.Multiple penetrating tensileeshear cracks appear in the s3-direction as the disturbance frequency f increases. 展开更多
关键词 True-triaxial compression Disturbance frequency Brittle failure Characteristic strength Deep excavation
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Experimental study on damage evolution and failure precursor characteristics of granite under thermal shock cycles
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作者 Zhenjiang Huang Mingxuan Shen +5 位作者 Yu Zhao Chaolin Wang Jing Bi Yongfa Zhang Shuang Dang Yuhang Zhao 《International Journal of Mining Science and Technology》 2026年第1期125-148,共24页
Investigating the damage evolution of surrounding rock under thermal shock cycles is crucial for ensuring the stability of engineering rock masses.This study performed Brazilian splitting tests on granite specimens un... Investigating the damage evolution of surrounding rock under thermal shock cycles is crucial for ensuring the stability of engineering rock masses.This study performed Brazilian splitting tests on granite specimens under varying temperature and cycle conditions,employing acoustic emission monitoring,digital image correlation,and three-dimensional scanning technology.A systematic analysis was conducted on the patterns of damage evolution,failure precursor,and response mechanisms under combined thermal and cyclic loading.Experimental results show that both P-wave velocity and tensile strength degrade significantly with increasing temperature and cycle count,with temperature having a more pronounced effect than cycle count.Notably,damage evolution exhibits a dual-threshold behavior in which degradation accelerates markedly above 400℃ and stabilizes after 5 thermal cycles.Fracture surfaces evolve from initially planar to rugged morphologies,with peak-valley height differences at 600℃ being approximately three times greater than those at 200℃.Furthermore,based on acoustic emission energy entropy analysis,we introduce a novel failure precursor indicator where the sustained increase and critical surge in average entropy serve as reliable early-warning signals for impending rock failure.These findings establish a solid theoretical basis and practical methodology for damage assessment and instability early-warning systems in high-temperature rock engineering. 展开更多
关键词 GRANITE Thermal shock cycles Acoustic emission Thermal damage failure precursor
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Xijiaqi Formula attenuates cognitive dysfunction by inhibiting neuroinflammation and promoting neuroplasticity in rats with chronic heart failure
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作者 Jie Chen Xuefen Wu +8 位作者 Qian Zhang Hongcai Shang Wanting Li Linnan Zhou Xinyu Chu Guiyang Xia Huan Xia Xiaohong Wei Sheng Lin 《Chinese Journal of Natural Medicines》 2026年第1期73-88,共16页
Chronic heart failure(CHF)impairs cognitive function.Xijiaqi Formula(XJQ),a traditional Chinese medicine(TCM)used clinically to treat CHF,demonstrates potential for improving cognition in CHF patients.However,its prec... Chronic heart failure(CHF)impairs cognitive function.Xijiaqi Formula(XJQ),a traditional Chinese medicine(TCM)used clinically to treat CHF,demonstrates potential for improving cognition in CHF patients.However,its precise mechanism in treating post-CHF cognitive dysfunction remains unclear.This study systematically investigates XJQ’s effects on post-CHF cognitive dysfunction and the underlying mechanisms.The components of XJQ were identified through liquid chromatography-mass spectrometry.CHF was induced in rats via ligation of the left anterior descending coronary artery,followed by six weeks of XJQ treatment.Cardiac function was evaluated through echocardiography and hemodynamic parameters,while cognitive function was assessed using Morris water maze(MWM)and open field tests(OFT).XJQ treatment enhanced both cardiac and cognitive functions in CHF rats.Network pharmacology identified 12 core active components of XJQ and indicated its effect on cognitive dysfunction involved regulating synapses,inflammation,and phosphodiesterase 4(PDE4)-dependent cyclic adenosine monophosphate(cAMP)signaling.XJQ inhibited microglial and astrocyte activation,decreased proinflammatory cytokines,and mitigated neuronal damage.Notably,XJQ promoted synaptic repair and dendritic growth by downregulating PDE4 and upregulating cAMP,protein kinase A(PKA),cAMP-response element binding protein(CREB),brain-derived neurotrophic factor(BDNF),PSD95,and synapsin I levels.Molecular docking and Bio-layer interferometry assays confirmed direct binding of quercetin,kaempferol,isorhamnetin,and darutoside to PDE4.In conclusion,XJQ alleviates neuroinflammation and enhances synaptic plasticity to improve cognitive dysfunction in CHF rats via the PDE4/cAMP/PKA/CREB signaling pathway.These findings provide valuable insight into the heart-brain axis. 展开更多
关键词 Xijiaqi Formula Cognitive dysfunction Chronic heart failure Synaptic plasticity NEUROINFLAMMATION PDE4
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Qi deficiency syndrome in heart failure:integrative analysis reveals CISD2-linked lipid metabolic dysregulation and prognostic implications
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作者 Jia-Mei Huang Lu-Hua Xu +6 位作者 Yu-Wen Qi Jie-Ni Fang Teng-Yang Zhai Zhi-Cong Zeng Hong-Cai Shang Rong-Feng Yang Feng-Xia Lin 《Traditional Medicine Research》 2026年第4期39-49,共11页
Background:“Qi deficiency”(a pathological state where the body’s vital energy(Qi)is insufficient or weakened,impairing physiological functions and diminishing the body’s ability to perform daily activities,defend ... Background:“Qi deficiency”(a pathological state where the body’s vital energy(Qi)is insufficient or weakened,impairing physiological functions and diminishing the body’s ability to perform daily activities,defend against illness,and maintain homeostasis)syndrome is considered a critical syndrome in traditional Chinese medicine(TCM)and is associated with poor prognosis in heart failure(HF).This study investigates the clinical,metabolic,and transcriptomic differences between heart failure patients with and without Qi deficiency syndrome.Methods:56 heart failure patients were evaluated using a Qi deficiency syndrome scale and divided into Qi deficiency syndrome(QD)and non-Qi deficiency(non-QD)groups based on the median score.Clinical characteristics,including baseline N-terminal pro-B-type natriuretic peptide(NT-proBNP),left ventricular ejection fraction(LVEF),total diuretic use during hospitalization,and 90-day rehospitalization rates,were compared between the groups.Differentially expressed genes(DEGs)and differential metabolites were identified,followed by enrichment analyses and validation using qPCR and Western blot in AC16 cardiomyocytes.Results:QD patients exhibited significantly higher NT-proBNP levels,lower LVEF,and increased 90-day rehospitalization rates.Metabolomic profiling revealed lipid metabolism disruptions,notably in linoleic acid and phospholipid pathways.Transcriptomic analysis highlighted 17 DEGs,including CISD2,a critical mitochondrial regulator,which was downregulated in QD patients.Correlation analysis identified significant associations between DEGs(e.g.,CISD2,BPGM)and lipid metabolites such as PC(16:0/P-16:0).Functional knockdown of CISD2 in AC16 cells led to upregulation of lipid oxidation enzymes ALOX15 and CYP1A2,linking CISD2 dysfunction to lipid metabolic dysregulation.Conclusion:Qi deficiency is associated with more severe heart failure symptoms,worse prognosis,and distinct metabolic and transcriptomic profiles,particularly in lipid metabolism.CISD2 emerges as a potential therapeutic target,offering new avenues for integrating molecular insights with TCM approaches to optimize HF management. 展开更多
关键词 Qi deficiency syndrome heart failure lipid metabolism transcriptomic alterations CISD2
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Heavy-ions-induced failure mechanisms and structural damage in SiC MOSFETs under complex irradiation conditions
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作者 Yiping Xiao Chaoming Liu +4 位作者 Jiaming Zhou Le Gao Mingzheng Wang Tianqi Wang and Mingxue Huo 《Chinese Physics B》 2026年第1期599-606,共8页
The failure mechanisms and structural damage of SiC MOSFETs induced by heavy ion irradiation were demonstrated.The findings reveal three degradation modes,depending on the drain voltage.At a relatively low voltage,the... The failure mechanisms and structural damage of SiC MOSFETs induced by heavy ion irradiation were demonstrated.The findings reveal three degradation modes,depending on the drain voltage.At a relatively low voltage,the damage is triggered by the formation and activation of gate latent damage(LDs),with damage concentrated in the gate oxide.The second degradation mode involves permanent leakage current degradation,with damage progressively transitioning from the oxide to the SiC material as the drain voltage escalates.Ultimately,the device undergoes catastrophic burnout above certain voltages,characterized by the lattice temperature reaching the sublimation point of SiC,resulting in surface cavity and complete structural destruction.This paper presents a comprehensive investigation of SiC MOSFETs under heavy ion exposure,providing radiation resistance methods of SiC-based devices for aerospace applications. 展开更多
关键词 heavy ion irradiation silicon carbide(SiC)MOSFETs structural damage failure mechanism
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Experimental and theoretical investigation of face failure and ground collapse during slurry pressure-balanced shield tunneling in saturated sand
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作者 Mengzhe Huo Weizhong Chen +3 位作者 Jingqiang Yuan Yunfa Li Yubiao Liu Qun Sui 《Journal of Rock Mechanics and Geotechnical Engineering》 2026年第2期1320-1336,共17页
Shield tunneling in saturated ground poses challenges due to the potential risk of ground collapse resulting from seepage force and inadequate support pressure.This study employed a laboratory model test and a theoret... Shield tunneling in saturated ground poses challenges due to the potential risk of ground collapse resulting from seepage force and inadequate support pressure.This study employed a laboratory model test and a theoretical validation to elucidate the mechanisms of face failure and subsequent ground collapse in saturated ground during slurry pressure-balanced shield(SPBS)tunneling operations.A slurry circulation system was developed to ensure steady shield tunneling and to replicate the phenomena of ground collapse.Investigations into shield tunneling parameters and ground responses,including soil pressure,pore water pressure,and surface subsidence,were conducted to understand the mechanisms of face failure and subsequent ground collapse.The theoretical solution for the critical collapse pressure of the tunnel face,based on the rotational failure mechanism,was validated through the comparison with the experimentally determined critical collapse pressure.The results indicate that:(1)appropriate adjustments of tunneling parameters are crucial for promoting filtercake formation,maintaining chamber pressure,and minimizing ground subsidence;(2)chamber pressure,soil pressure,pore water pressure,and ground subsidence are closely correlated with shield tunneling parameters and the formation of filter cake;(3)ground collapse follows a continuous failure mode due to the destruction of filtercake and the decrease in chamber pressure;(4)the soil pressure at the cutterhead is more sensitive to disturbances from shield tunneling than chamber pressure;and(5)experimentally determined critical collapse pressures is consistent with the theoretical solution of limit analysis. 展开更多
关键词 Slurry shield model test Saturated sand Ground collapse Tunnel face stability Rotational failure mechanism
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Energy absorption properties and failure modes of flexible UHMWPE foam protective sandwich structure subjected to low-velocity impact
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作者 Xiaoke Liu Kejing Yu Pengwan Chen 《Defence Technology(防务技术)》 2026年第2期32-48,共17页
Flexible materials play a crucial role in protecting against behind armour blunt trauma(BABT).However,their compliance complicates the understanding of failure mechanisms and energy absorption.This study used a combin... Flexible materials play a crucial role in protecting against behind armour blunt trauma(BABT).However,their compliance complicates the understanding of failure mechanisms and energy absorption.This study used a combined experimental and numerical approach to investigate the response and failure modes of a flexible ultra-high-molecular-weight polyethylene(UHMWPE)foam protective sandwich structure(UFPSS)under low-velocity impact(LVI).A finite element(FE)model,accounting for nonlinear large deformation and strain-rate-dependent material behavior,was developed for a woven-UFPSS(featuring a plain-woven fabric structure)subjected to a 50 J impact.Experimental and numerical results showed strong agreement in peak force(error<5%),maximum displacement(error<6%),and buffer time(error<8%).The impact's kinetic energy was mainly converted into internal energy of the fabric and foam materials(~50%),viscous dissipation in the foam core(12%-15%),frictional work at the contact interfaces(5%-6%),and work by the pneumatic fixture clamping force(~38%).This study provides the first investigation of the LVI performance of sandwich structures with all soft material layers,offering significant insights for the application of compliant materials in protective fields. 展开更多
关键词 Sandwich structure Ultra-high-molecular-weight polyethylene(UHMWPE) Low-velocity impact(LVI) failure mode Energy absorption
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