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Quaternary ammonium-induced multidrug tolerant Streptococcus mutans persisters elevate cariogenic virulence in vitro 被引量:2
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作者 Ya-Ling Jiang Wei Qiu +8 位作者 Xue-Dong Zhou Hao Li Jun-Zhuo Lu Hockin HK Xu Xian Peng Ming-Yun Li Ming-Ye Feng Lei Cheng Biao Ren 《International Journal of Oral Science》 SCIE CAS CSCD 2017年第4期224-231,共8页
Dental caries are the most prevalent chronic infections in the oral cavity, and Streptococcus mutans acts as the main cariogenic bacterial species. Antibacterial quaternary ammonium compounds (QAs) have been develop... Dental caries are the most prevalent chronic infections in the oral cavity, and Streptococcus mutans acts as the main cariogenic bacterial species. Antibacterial quaternary ammonium compounds (QAs) have been developed to preveFnt or treat dental caries. However, there is no report on the tolerance of S. mutans to QAs. In this study, we investigated the development of S. mutans persistence induced by a novel dental caries defensive agent, dimethylaminododecyl methacrylate (DMADDM), for the first time. Typical biphasic killing kinetics for persisters were observed in both S. mutans planktonic and biofilm cultures challenged by DMADDM at concentrations of 20 and 200 pg.mL- z respectively. The persisters tolerated six other antibiotics with different antibacterial mechanisms, while only daptomycin and vancomycin could slightly reduce the persister numbers in planktonic cultures. The distribution of persisters in DMADDM-treated biofilms was similar to that in the untreated control, except that the total biomass and biofilm height were significantly reduced. A higher exopolysaccharides (EPS):bacteria ratio was observed in DMADDM-treated biofilms. Persisters in biofilms significantly upregulated gtf gene expression, indicating an increase in the bacteria's ability to produce EPS and an elevated capability of cariogenic virulence. Carbon source metabolism was significantly reduced, as related metabolic genes were all downregulated in persisters. Concentrations of 0.1 mM, 1 mM and 10 mM of extra glucose significantly reduced the number of persisters both in planktonic and biofilm conditions. The formation of non- inheritable and multidrug tolerant persisters induced by DMADDM suggested that drug tolerance and new persistent eradication strategies should be considered for oral antibacterial agents. 展开更多
关键词 antibacterial quaternary ammoniums dental caries PERSISTENCE multidrug tolerance Streptococcus mutans biofilms
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Bacterial persisters: molecular mechanisms and therapeutic development
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作者 Hongxia Niu Jiaying Gu Ying Zhang 《Signal Transduction and Targeted Therapy》 SCIE CSCD 2024年第8期3305-3336,共32页
Persisters refer to genetically drug susceptible quiescent(non-growing or slow growing)bacteria that survive in stress environments such as antibiotic exposure,acidic and starvation conditions.These cells can regrow a... Persisters refer to genetically drug susceptible quiescent(non-growing or slow growing)bacteria that survive in stress environments such as antibiotic exposure,acidic and starvation conditions.These cells can regrow after stress removal and remain susceptible to the same stress.Persisters are underlying the problems of treating chronic and persistent infections and relapse infections after treatment,drug resistance development,and biofilm infections,and pose significant challenges for effective treatments.Understanding the characteristics and the exact mechanisms of persister formation,especially the key molecules that affect the formation and survival of the persisters is critical to more effective treatment of chronic and persistent infections.Currently,genes related to persister formation and survival are being discovered and confirmed,but the mechanisms by which bacteria form persisters are very complex,and there are still many unanswered questions.This article comprehensively summarizes the historical background of bacterial persisters,details their complex characteristics and their relationship with antibiotic tolerant and resistant bacteria,systematically elucidates the interplay between various bacterial biological processes and the formation of persister cells,as well as consolidates the diverse anti-persister compounds and treatments.We hope to provide theoretical background for in-depth research on mechanisms of persisters and suggest new ideas for choosing strategies for more effective treatmentofpersistent infections. 展开更多
关键词 MECHANISMS TREATMENT persist
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Identification of Persister Drug Combination Clinafloxacin+Cefuroxime+Gentamicin That Eradicates Persistent Pseudomonas aeruginosa Infection in a Murine Cystic Fibrosis Model 被引量:2
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作者 Yuting Yuan Rebecca Yee +4 位作者 Naina Gour Xinzhong Dong Jie Feng Wanliang Shi Ying Zhang 《Infectious Microbes & Diseases》 CSCD 2023年第1期21-28,共8页
Pseudomonas aeruginosa can cause persistent infections,such as biofilm infections,in cystic fibrosis patients,which are difficult to cure due to non-growing persister bacteria that are not effectively killed by the cu... Pseudomonas aeruginosa can cause persistent infections,such as biofilm infections,in cystic fibrosis patients,which are difficult to cure due to non-growing persister bacteria that are not effectively killed by the current treatments.While antibiotic activity against growing P.aeruginosa is well documented,their activity against non-growing stationary phase cultures is less clear.Here,we evaluated six major classes of antibiotics,including cell wall and cell membrane inhibitors,protein synthesis inhibitors,DNA synthesis inhibitors,RNA synthesis inhibitors,sulfa drugs and nitrofurantoin,for their activity against growing and non-growing P.aeruginosa.We foundthat cell wall and cell membrane inhibitors(cefuroxime and colistin),DNA synthesis inhibitors(clinafloxacin)and sulfa drugs(sulfamethoxazole)had good activity against stationary-phase bacteria,while protein synthesis inhibitors(gentamicin),RNA synthesis inhibitor(rifampin)and nitrofurantoin showed relatively poor activity.Clinafloxacin was the only drug able to completely eradicate stationary-phase bacteria within four days.The cefuroxime+gentamicin+clinafloxacin combination was able to kill all bacteria from a biofilm within two days,whereas the clinically used drug combination cefuroxime+gentamicin/colistin only partially killed the biofilmbacteria.In amurine persistent cystic fibrosis lung infectionmodel,only the cefuroxime+gentamicin+clinafloxacin drug combination eradicated all bacteria from the lungs,whereas clinafloxacin alone,cefuroxime+clinafloxacin or the currently recommended drug combination cefuroxime+gentamicin failed to do so.The complete eradication is a property of the clinafloxacin combination,as the otherwise identical levofloxacin combination did not clear the bacterial loads from the lungs.Our findings offer new therapeutic options for more effective treatment of persistent P.aeruginosa infections,with possible implications for treating other persistent infections. 展开更多
关键词 Pseudomonas aeruginosa persisters stationary-phase bacteria BIOFILM CLINAFLOXACIN cystic fibrosis
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肉桂醛诱导酿酒酵母Persisters细胞的形成 被引量:4
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作者 沈青山 周威 +2 位作者 王淼焱 莫海珍 胡梁斌 《现代食品科技》 EI CAS 北大核心 2016年第7期53-59,共7页
本文研究了肉桂醛对酿酒酵母persister细胞形成的影响。通过96孔板微量法测定肉桂醛对酿酒酵母生长的最小抑制浓度(MIC)为0.4 m M;采用流式细胞仪以及梯度稀释滴平板计数法研究了肉桂醛处理后酿酒酵母persister细胞的形成情况。结果表明... 本文研究了肉桂醛对酿酒酵母persister细胞形成的影响。通过96孔板微量法测定肉桂醛对酿酒酵母生长的最小抑制浓度(MIC)为0.4 m M;采用流式细胞仪以及梯度稀释滴平板计数法研究了肉桂醛处理后酿酒酵母persister细胞的形成情况。结果表明,肉桂醛可以抑制酿酒酵母生长,且能够诱导酿酒酵母细胞形成persister状态,该状态下的细胞对两性霉素B产生耐药性。进一步研究发现肉桂醛处理后可以使酿酒酵母细胞停滞在细胞周期的任何阶段,而雷帕霉素诱导的细胞自噬只能停留在G1期,所以酿酒酵母perisister与自噬状态存在区别。目前,对于Persister的研究集中在原核微生物,对真核生物persister的研究非常有限。由于persister群体通常占总群体极小一部分,这就给基因水平上研究persister的形成机制带来很大的挑战。本研究发现肉桂醛处理酿酒酵母细胞后,可以促使其大部分细胞形成persister。这就为从基因水平上认识真核生物persister的形成机制提供了方法,实验结果表明YGL基因也与酿酒酵母persister的形成有很大关系。 展开更多
关键词 肉桂醛 酿酒酵母 persister 诱导
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Multiframe-integrated, in-sensor computing using persistent photoconductivity 被引量:1
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作者 Xiaoyong Jiang Minrui Ye +7 位作者 Yunhai Li Xiao Fu Tangxin Li Qixiao Zhao Jinjin Wang Tao Zhang Jinshui Miao Zengguang Cheng 《Journal of Semiconductors》 EI CAS CSCD 2024年第9期36-41,共6页
The utilization of processing capabilities within the detector holds significant promise in addressing energy consumption and latency challenges. Especially in the context of dynamic motion recognition tasks, where su... The utilization of processing capabilities within the detector holds significant promise in addressing energy consumption and latency challenges. Especially in the context of dynamic motion recognition tasks, where substantial data transfers are necessitated by the generation of extensive information and the need for frame-by-frame analysis. Herein, we present a novel approach for dynamic motion recognition, leveraging a spatial-temporal in-sensor computing system rooted in multiframe integration by employing photodetector. Our approach introduced a retinomorphic MoS_(2) photodetector device for motion detection and analysis. The device enables the generation of informative final states, nonlinearly embedding both past and present frames. Subsequent multiply-accumulate (MAC) calculations are efficiently performed as the classifier. When evaluating our devices for target detection and direction classification, we achieved an impressive recognition accuracy of 93.5%. By eliminating the need for frame-by-frame analysis, our system not only achieves high precision but also facilitates energy-efficient in-sensor computing. 展开更多
关键词 in-sensor MOS2 PHOTODETECTOR persistent photoconductivity reservoir computing
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The Role of Underlying Boundary Forcing in Shaping the Recent Decadal Change of Persistent Anomalous Activity over the Ural Mountains 被引量:1
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作者 Ting LEI Shuanglin LI 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第8期1496-1510,1661-1667,共22页
Observational analyses demonstrate that the Ural persistent positive height anomaly event(PAE) experienced a decadal increase around the year 2000, exhibiting a southward displacement afterward. These decadal variatio... Observational analyses demonstrate that the Ural persistent positive height anomaly event(PAE) experienced a decadal increase around the year 2000, exhibiting a southward displacement afterward. These decadal variations are related to a large-scale circulation shift over the Eurasian Continent. The effects of underlying sea ice and sea surface temperature(SST) anomalies on the Ural PAE and the related atmospheric circulation were explored by Atmospheric Model Intercomparison Project(AMIP) experiments from the Coupled Model Intercomparison Project Phase 6 and by sensitivity experiments using the Atmospheric General Circulation Model(AGCM). The AMIP experiment results suggest that the underlying sea ice and SST anomalies play important roles. The individual contributions of sea ice loss in the Barents-Kara Seas and the SST anomalies linked to the phase transition of the Pacific Decadal Oscillation(PDO) and Atlantic Multidecadal Oscillation(AMO) are further investigated by AGCM sensitivity experiments isolating the respective forcings.The sea ice decline in Barents-Kara Seas triggers an atmospheric wave train over the Eurasian mid-to-high latitudes with positive anomalies over the Urals, favoring the occurrence of Ural PAEs. The shift in the PDO to its negative phase triggers a wave train propagating downstream from the North Pacific. One positive anomaly lobe of the wave train is located over the Ural Mountains and increases the PAE there. The negative-to-positive transition of the AMO phase since the late-1990s causes positive 500-h Pa height anomalies south of the Ural Mountains, which promote a southward shift of Ural PAE. 展开更多
关键词 Ural persistent anomaly Pacific decadal oscillation Atlantic multidecadal oscillation sea ice loss in Barents-Kara Seas
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Felodipine enhances aminoglycosides efficacy against implant infections caused by methicillin-resistant Staphylococcus aureus,persisters and biofilms 被引量:1
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作者 Shutao Zhang Xinhua Qu +6 位作者 Juyang Jiao Haozheng Tang Minqi Wang You Wang Hongtao Yang Weien Yuan Bing Yue 《Bioactive Materials》 SCIE 2022年第8期272-289,共18页
Methicillin-resistant Staphylococcus aureus(MRSA),biofilms,and persisters are three major factors leading to recurrent and recalcitrant implant infections.Although antibiotics are still the primary treatment for chron... Methicillin-resistant Staphylococcus aureus(MRSA),biofilms,and persisters are three major factors leading to recurrent and recalcitrant implant infections.Although antibiotics are still the primary treatment for chronic implant infections in clinical,only few drugs are effective in clearing persisters and formed biofilms.Here,felodipine,a dihydropyridine calcium channel blocker,was reported for the first time to have antibacterial effects against MRSA,biofilm,and persisters.Even after continuous exposure to sub-lethal concentrations of felodipine,bacteria are less likely to develop resistance.Besides,low doses of felodipine enhances the antibacterial activity of gentamicin by inhibiting the expression of protein associated with aminoglycoside resistance(aacA-aphD).Next,biofilm eradication test and persisters killing assay suggested felodipine has an excellent bactericidal effect against formed biofilms and persisters.Furthermore,the result of protein profiling,and quantitative metabonomics analysis indicated felodipine reduce MRSA virulence(agrABC),biofilm formation and TCA cycle.Then,molecular docking showed felodipine inhibit the growth of persisters by binding to the H pocket of ClpP protease,which could lead to substantial protein degradation.Furthermore,murine infection models suggested felodipine in combination with gentamicin alleviate bacterial burden and inflammatory response.In conclusion,low dose of felodipine might be a promising agent for biomaterial delivery to enhance aminoglycosides efficacy against implant infections caused by MRSA,biofilm,and persisters. 展开更多
关键词 AMINOGLYCOSIDES FELODIPINE persisters Methicillin-resistant Staphylococcus aureus Implant infection
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The Persistence and Zonal Scale of Atmospheric Dipolar Modes
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作者 Jie SONG 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第3期478-492,共15页
This study investigates the relationship between the persistence and the zonal scale of atmospheric dipolar modes(DMs). Results from the daily data of ERA5 and the long-term output of an idealized atmospheric model sh... This study investigates the relationship between the persistence and the zonal scale of atmospheric dipolar modes(DMs). Results from the daily data of ERA5 and the long-term output of an idealized atmospheric model show that the atmospheric DMs with a broader(narrower) zonal scale dipolar structure possess a longer(shorter) persistence. A detailed vorticity budget analysis indicates that the persistence of a hemispheric-scale DM(1/1 DM) and a regional or sectoral DM(1/8 DM) in the model both largely rely on the persistence of the nonlinear eddy forcing. Linear terms can indirectly reduce the persistence of the anomalous nonlinear eddy forcing in a 1/8 DM by modifying the baroclinicity via the arousal of anomalous vertical motions. Therefore, the atmospheric DMs with a broader(narrower) zonal scale possess a longer(shorter) persistence because the effects of the linear terms are less(more) pronounced when the atmospheric DMs have better(worse) zonal symmetry. Further analyses show that the positive eddy feedback effect is weak or even absent in a 1/8DM and the high-frequency eddy forcing acts more like a concomitant phenomenon rather than a leading driving factor for a 1/8 DM. Thus, the hemispheric-scale DM and the regional or sectoral DMs are different, not only in their persistence but also in their dynamics. 展开更多
关键词 NAM NAO eddy feedback PERSISTENCE linear term
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THE PERSISTENCE OF SOLUTIONS IN A NONLOCAL PREDATOR-PREY SYSTEM WITH A SHIFTING HABITAT
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作者 赵敏 袁荣 《Acta Mathematica Scientia》 SCIE CSCD 2024年第3期1096-1114,共19页
In this paper,we mainly study the propagation properties of a nonlocal dispersal predator-prey system in a shifting environment.It is known that Choi et al.[J Differ Equ,2021,302:807-853]studied the persistence or ext... In this paper,we mainly study the propagation properties of a nonlocal dispersal predator-prey system in a shifting environment.It is known that Choi et al.[J Differ Equ,2021,302:807-853]studied the persistence or extinction of the prey and of the predator separately in various moving frames.In particular,they achieved a complete picture in the local diffusion case.However,the question of the persistence of the prey and of the predator in some intermediate moving frames in the nonlocal diffusion case was left open in Choi et al.'s paper.By using some a prior estimates,the Arzelà-Ascoli theorem and a diagonal extraction process,we can extend and improve the main results of Choi et al.to achieve a complete picture in the nonlocal diffusion case. 展开更多
关键词 predator-prey system PERSISTENCE nonlocal dispersal shifting environment
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Yield of alarm features in predicting significant endoscopic findings among hospitalized patients with dyspepsia
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作者 Lama Ibrahim Maamoun Basheer +1 位作者 Tawfik Khoury Wisam Sbeit 《World Journal of Gastroenterology》 SCIE CAS 2024年第26期3210-3220,共11页
BACKGROUND Dyspepsia is a very prevalent upper gastrointestinal tract symptoms complex.Some of these symptoms might arise from serious underlying diseases,so the promotion of evidence-based guidelines could potentiall... BACKGROUND Dyspepsia is a very prevalent upper gastrointestinal tract symptoms complex.Some of these symptoms might arise from serious underlying diseases,so the promotion of evidence-based guidelines could potentially better align evaluation and treatment.AIM To determine the value of alarm features as a predictive factor for significant endoscopic findings(SEFs)among hospitalized patients presenting with dyspepsia.METHODS We conducted a retrospective case-control study including information about 6208 endoscopic procedures performed for hospitalized patients.Patients were divided into two groups,with and without SEFs,and compared to elucidate the ability of the different alarm features to predict SEFs.RESULTS During the study,605 patients fulfilled the inclusion criteria.When the demographics and clinical characteristics of the two groups were compared,tachycardia(P<0.05),normocytic anemia,(P<0.05),leukocytosis(P<0.05),and hypoalbuminemia(P<0.05)documented on admission prior to endoscopy were strong predictors of SEFs.Among the alarm features,upper gastrointestinal bleeding,persistent vomiting,odynophagia[odds ratio(OR)=3.81,P<0.05;OR=1.75,P=0.03;and OR=7.81,P=0.07,respectively]were associated with SEFs.Unexplained weight loss was strongly associated with malignancy as an endoscopic finding(OR=2.05;P<0.05).In addition,long-term use of anti-aggregate medications other than aspirin(P<0.05)was correlated to SEFs.CONCLUSION Novel predictors of SEFs were elucidated in this study.These parameters could be used as an adjunctive in decision making regarding performing upper endoscopy in hospitalized patients with dyspepsia. 展开更多
关键词 DYSPEPSIA Endoscopy Weight loss Anti-aggregate medications Persistent vomiting ODYNOPHAGIA
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A Comprehensive Survey on Advanced Persistent Threat (APT) Detection Techniques
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作者 Singamaneni Krishnapriya Sukhvinder Singh 《Computers, Materials & Continua》 SCIE EI 2024年第8期2675-2719,共45页
The increase in number of people using the Internet leads to increased cyberattack opportunities.Advanced Persistent Threats,or APTs,are among the most dangerous targeted cyberattacks.APT attacks utilize various advan... The increase in number of people using the Internet leads to increased cyberattack opportunities.Advanced Persistent Threats,or APTs,are among the most dangerous targeted cyberattacks.APT attacks utilize various advanced tools and techniques for attacking targets with specific goals.Even countries with advanced technologies,like the US,Russia,the UK,and India,are susceptible to this targeted attack.APT is a sophisticated attack that involves multiple stages and specific strategies.Besides,TTP(Tools,Techniques,and Procedures)involved in the APT attack are commonly new and developed by an attacker to evade the security system.However,APTs are generally implemented in multiple stages.If one of the stages is detected,we may apply a defense mechanism for subsequent stages,leading to the entire APT attack failure.The detection at the early stage of APT and the prediction of the next step in the APT kill chain are ongoing challenges.This survey paper will provide knowledge about APT attacks and their essential steps.This follows the case study of known APT attacks,which will give clear information about the APT attack process—in later sections,highlighting the various detection methods defined by different researchers along with the limitations of the work.Data used in this article comes from the various annual reports published by security experts and blogs and information released by the enterprise networks targeted by the attack. 展开更多
关键词 Advanced persistent threats APT cyber security intrusion detection cyber attacks
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Characteristics and Mechanisms of Persistent Wet–Cold Events with Different Cold-air Paths in South China
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作者 Xiaojuan SUN Li CHEN +1 位作者 Chuhan LU Panxing WANG 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第6期1171-1183,共13页
We investigate the characteristics and mechanisms of persistent wet–cold events(PWCEs)with different types of coldair paths.Results show that the cumulative single-station frequency of the PWCEs in the western part o... We investigate the characteristics and mechanisms of persistent wet–cold events(PWCEs)with different types of coldair paths.Results show that the cumulative single-station frequency of the PWCEs in the western part of South China is higher than that in the eastern part.The pattern of single-station frequency of the PWCEs are“Yangtze River(YR)uniform”and“east–west inverse”.The YR uniform pattern is the dominant mode,so we focus on this pattern.The cold-air paths for PWCEs of the YR uniform pattern are divided into three types—namely,the west,northwest and north types—among which the west type accounts for the largest proportion.The differences in atmospheric circulation of the PWCEs under the three types of paths are obvious.The thermal inversion layer in the lower troposphere is favorable for precipitation during the PWCEs.The positive water vapor budget for the three types of PWCEs mainly appears at the southern boundary. 展开更多
关键词 persistent wet–cold events cold-air paths circulation characteristics water vapor
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Numerical Analysis of Bacterial Meningitis Stochastic Delayed Epidemic Model through Computational Methods
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作者 Umar Shafique Mohamed Mahyoub Al-Shamiri +3 位作者 Ali Raza Emad Fadhal Muhammad Rafiq Nauman Ahmed 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第10期311-329,共19页
Based on theWorld Health Organization(WHO),Meningitis is a severe infection of the meninges,the membranes covering the brain and spinal cord.It is a devastating disease and remains a significant public health challeng... Based on theWorld Health Organization(WHO),Meningitis is a severe infection of the meninges,the membranes covering the brain and spinal cord.It is a devastating disease and remains a significant public health challenge.This study investigates a bacterial meningitis model through deterministic and stochastic versions.Four-compartment population dynamics explain the concept,particularly the susceptible population,carrier,infected,and recovered.The model predicts the nonnegative equilibrium points and reproduction number,i.e.,the Meningitis-Free Equilibrium(MFE),and Meningitis-Existing Equilibrium(MEE).For the stochastic version of the existing deterministicmodel,the twomethodologies studied are transition probabilities and non-parametric perturbations.Also,positivity,boundedness,extinction,and disease persistence are studiedrigorouslywiththe helpofwell-known theorems.Standard and nonstandard techniques such as EulerMaruyama,stochastic Euler,stochastic Runge Kutta,and stochastic nonstandard finite difference in the sense of delay have been presented for computational analysis of the stochastic model.Unfortunately,standard methods fail to restore the biological properties of the model,so the stochastic nonstandard finite difference approximation is offered as an efficient,low-cost,and independent of time step size.In addition,the convergence,local,and global stability around the equilibria of the nonstandard computational method is studied by assuming the perturbation effect is zero.The simulations and comparison of the methods are presented to support the theoretical results and for the best visualization of results. 展开更多
关键词 Bacterial Meningitis disease stochastic delayed model stability analysis extinction and persistence computational methods
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Detecting APT-Exploited Processes through Semantic Fusion and Interaction Prediction
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作者 Bin Luo Liangguo Chen +1 位作者 Shuhua Ruan Yonggang Luo 《Computers, Materials & Continua》 SCIE EI 2024年第2期1731-1754,共24页
Considering the stealthiness and persistence of Advanced Persistent Threats(APTs),system audit logs are leveraged in recent studies to construct system entity interaction provenance graphs to unveil threats in a host.... Considering the stealthiness and persistence of Advanced Persistent Threats(APTs),system audit logs are leveraged in recent studies to construct system entity interaction provenance graphs to unveil threats in a host.Rule-based provenance graph APT detection approaches require elaborate rules and cannot detect unknown attacks,and existing learning-based approaches are limited by the lack of available APT attack samples or generally only perform graph-level anomaly detection,which requires lots of manual efforts to locate attack entities.This paper proposes an APT-exploited process detection approach called ThreatSniffer,which constructs the benign provenance graph from attack-free audit logs,fits normal system entity interactions and then detects APT-exploited processes by predicting the rationality of entity interactions.Firstly,ThreatSniffer understands system entities in terms of their file paths,interaction sequences,and the number distribution of interaction types and uses the multi-head self-attention mechanism to fuse these semantics.Then,based on the insight that APT-exploited processes interact with system entities they should not invoke,ThreatSniffer performs negative sampling on the benign provenance graph to generate non-existent edges,thus characterizing irrational entity interactions without requiring APT attack samples.At last,it employs a heterogeneous graph neural network as the interaction prediction model to aggregate the contextual information of entity interactions,and locate processes exploited by attackers,thereby achieving fine-grained APT detection.Evaluation results demonstrate that anomaly-based detection enables ThreatSniffer to identify all attack activities.Compared to the node-level APT detection method APT-KGL,ThreatSniffer achieves a 6.1%precision improvement because of its comprehensive understanding of entity semantics. 展开更多
关键词 Advanced persistent threat provenance graph multi-head self-attention graph neural network
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Effect of autologous serum after amniotic membrane transplantation for persistent corneal ulcers
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作者 Rozaliya Hristova Petya Yankova +2 位作者 Georgi Markov Alexander Oscar Yani Zdravkov 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2024年第9期1639-1644,共6页
AIM:To investigate the effect of adding autologous serum eye drops to the postoperative regime after amniotic membrane transplantation for severe persistent corneal ulcers.METHODS:Forty eyes of 40 patients with persis... AIM:To investigate the effect of adding autologous serum eye drops to the postoperative regime after amniotic membrane transplantation for severe persistent corneal ulcers.METHODS:Forty eyes of 40 patients with persistent corneal ulcers were randomly assigned to artificial tears(sodium hyaluronate 0.2%,ATs group,n=20)or autologous serum eye drops(ASEDs,n=20)following treatment with amniotic membrane transplantation.Digital slit lamp images were acquired from all patients before and 30d post treatment.The area with fibrovascular tissue was calculated using Image J.Central corneal sensitivity was assessed by Cochet-Bonnet aesthesiometry before and one month after treatment.Scar tissue transparency was assessed with a novel optical densitometry.RESULTS:Mean age of patients was 61.65±16.47y and 57.3±19.11y in the ATs group and ASEDs group,respectively.Twenty-two male and 18 female patients were included in the study.The improvement in visual acuity was significantly greater in the ASEDs group(0.14±0.04)than the ATs(0.08±0.04;P=0.00046).Cochet-Bonnet aesthesiometry improved significantly after treatment with a similar rate between groups.There were no statistically significant differences in the area of postoperative fibrovascular tissue between the two groups(P=0.082).The success rate in the two groups was similar.The difference in densitometry between the ATs and ASEDs group was statistically significant(P=0.042)with greater reduction from baseline in the ASEDS group.CONCLUSION:Autologous serum eye drops can lead to better visual acuity,more stable results and improved densitometry and should be considered in the postoperative care following amniotic membrane transplantation. 展开更多
关键词 autologous serum amniotic membrane ocular surface persistent corneal ulcer
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Hydromassage of macular hole edges for large and persistent full-thickness macular holes
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作者 Yi Cai Wen-Bo Liu +5 位作者 Duo Wei Xun Deng Xiao-Xin Li Ming-Wei Zhao Xuan Shi Jian-Hong Liang 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2024年第3期551-557,共7页
●AIM:To introduce the macular hole(MH)hydromassage technique as a potentially beneficial approach for the treatment of large or persistent MH.●METHODS:This retrospective observational case series comprised 16 consec... ●AIM:To introduce the macular hole(MH)hydromassage technique as a potentially beneficial approach for the treatment of large or persistent MH.●METHODS:This retrospective observational case series comprised 16 consecutive patients(17 eyes)diagnosed with MH.Inclusion criteria involved a hole aperture diameter larger than 600μm or the presence of an unclosed MH larger than 600μm following the previous vitrectomy.Standard MH repair procedures were administered in all cases,involving the manipulation and aspiration of the hole margin through the application of water flow with a soft-tip flute needle.A comprehensive assessment was conducted for each case before and after surgery,and optical coherence tomography(OCT)images were captured at every follow-up point.●RESULTS:The mean preoperative aperture diameter was 747±156μm(range 611-1180μm),with a mean base diameter of 1390±435μm(range 578-2220μm).Following surgery,all cases achieved complete anatomical closure of MH,with 13 cases(76.5%)exhibiting type 1 closure and 4 cases(23.5%)demonstrating type 2 closure.No significant differences were observed in the preoperative OCT variables between the two closure types.Eyes with type 1 closure showed a significantly improved visual acuity(0.70±0.10,range 0.50-0.80)compared to those with type 2 closure(0.90±0.12,range 0.80-1.00,P=0.014).●CONCLUSION:The MH hydromassage technique demonstrates promising results,achieving acceptable closure rates in cases of large or persistent MH.This technique may serve as an effective adjunctive maneuver during challenging MH surgery. 展开更多
关键词 macular hole large macular hole persistent macular hole optical coherence tomography surgical technique hydromassage
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Mechanisms to explain soil liquefaction triggering,development,and persistence during an earthquake
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作者 Fernando Teixeira 《Earthquake Science》 2024年第6期558-573,共16页
Mechanisms have been proposed to explain the triggering,development,and persistence of soil liquefaction.The mechanism explaining the horizontal failure plane(triggering)and its depth below the phreatic surface is gov... Mechanisms have been proposed to explain the triggering,development,and persistence of soil liquefaction.The mechanism explaining the horizontal failure plane(triggering)and its depth below the phreatic surface is governed by the flux properties and effective stress at that plane.At the failure plane,the pore water pressure was higher than the effective stress,and the volume change was the highest.The pore water pressure is a function of the soil profile features(particularly the phreatic zone width)and bedrock motion(horizontal acceleration).The volume change at the failure plane is a function of the intrinsic permeability of the soil and bedrock displacement.The failure plane was predicted to occur during the oscillation with the highest amplitude,disregarding further bedrock motion,which was consistent with low seismic energy densities.Two mechanisms were proposed to explain the persistence of soil liquefaction.The first is the existence of low-permeability layers in the depth range in which the failure planes are predicted to occur.The other allows for the persistence and development of soil liquefaction;it is consistent with homogeneous soils and requires water inflow from bedrock water springs.The latter explains many of the features of soil liquefaction observed during earthquakes,namely,surficial effects,“instant”liquefaction,and the occurrence of short-and long-term changes in the level of the phreatic surfaces.This model(hypothesis),the relationship between the flux characteristics and loss of soil shear strength,provides self-consistent constraints on the depth below the phreatic surfaces where the failure planes are observed(expected to occur).It requires further experimental and observational evidence.Similar reasoning can be used to explain other saturated soil phenomena. 展开更多
关键词 soil liquefaction triggering soil liquefaction persistence intrinsic soil permeability impervious soil layers bedrock water springs
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Clinical study of neutrophil-to-lymphocyte ratio and platelet-tolymphocyte ratio in hypertriglyceridemia-induced acute pancreatitis and acute biliary pancreatitis with persistent organ failure
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作者 Mu-Sen Xu Jia-Le Xu +5 位作者 Xin Gao Shao-Jian Mo Jia-Yu Xing Jia-Hang Liu Yan-Zhang Tian Xi-Feng Fu 《World Journal of Gastrointestinal Surgery》 SCIE 2024年第6期1647-1659,共13页
BACKGROUND The neutrophil-to-lymphocyte ratio(NLR)and platelet-to-lymphocyte ratio(PLR)are novel inflammatory indicators that can be used to predict the severity and prognosis of various diseases.We categorize acute p... BACKGROUND The neutrophil-to-lymphocyte ratio(NLR)and platelet-to-lymphocyte ratio(PLR)are novel inflammatory indicators that can be used to predict the severity and prognosis of various diseases.We categorize acute pancreatitis by etiology into acute biliary pancreatitis(ABP)and hypertriglyceridemia-induced acute pancreatitis(HTGP).AIM To investigate the clinical significance of NLR and PLR in assessing persistent organ failure(POF)in HTGP and ABP.METHODS A total of 1450 patients diagnosed with acute pancreatitis(AP)for the first time at Shanxi Bethune Hospital between January 2012 and January 2023 were enrolled.The patients were categorized into two groups according to the etiology of AP:ABP in 530 patients and HTGP in 241 patients.We collected and compared the clinical data of the patients,including NLR,PLR,and AP prognostic scoring systems,within 48 h of hospital admission.RESULTS The NLR(9.1 vs 6.9,P<0.001)and PLR(203.1 vs 160.5,P<0.001)were significantly higher in the ABP group than in the HTGP group.In the HTGP group,both NLR and PLR were significantly increased in patients with severe AP and those with a SOFA score≥3.Likewise,in the ABP group,NLR and PLR were significantly elevated in patients with severe AP,modified computed tomography severity index score≥4,Japanese Severity Score≥3,and modified Marshall score≥2.Moreover,NLR and PLR showed predictive value for the development of POF in both the ABP and HTGP groups.CONCLUSION NLR and PLR vary between ABP and HTGP,are strongly associated with AP prognostic scoring systems,and have predictive potential for the occurrence of POF in both ABP and HTGP. 展开更多
关键词 Acute pancreatitis GALLSTONE HYPERTRIGLYCERIDEMIA Neutrophil-to-lymphocyte ratio Platelet-to-lymphocyte ratio Persistent organ failure
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Risk factors associated with intraoperative persistent hypotension in pancreaticoduodenectomy
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作者 Xing-Jun Wang Xi-Chen Xuan +6 位作者 Zhao-Chu Sun Shi Shen Fan Yu Na-Na Li Xue-Chun Chu Hui Yin You-Li Hu 《World Journal of Gastrointestinal Surgery》 SCIE 2024年第6期1582-1591,共10页
BACKGROUND Intraoperative persistent hypotension(IPH)during pancreaticoduodenectomy(PD)is linked to adverse postoperative outcomes,yet its risk factors remain unclear.AIM To clarify the risk factors associated with IP... BACKGROUND Intraoperative persistent hypotension(IPH)during pancreaticoduodenectomy(PD)is linked to adverse postoperative outcomes,yet its risk factors remain unclear.AIM To clarify the risk factors associated with IPH during PD,ensuring patient safety in the perioperative period.METHODS A retrospective analysis of patient records from January 2018 to December 2022 at the First Affiliated Hospital of Nanjing Medical University identified factors associated with IPH in PD.These factors included age,gender,body mass index,American Society of Anesthesiologists classification,comorbidities,medication history,operation duration,fluid balance,blood loss,urine output,and blood gas parameters.IPH was defined as sustained mean arterial pressure<65 mmHg,requiring prolonged deoxyepinephrine infusion for>30 min despite additional deoxyepinephrine and fluid treatments.RESULTS Among 1596 PD patients,661(41.42%)experienced IPH.Multivariate logistic regression identified key risk factors:increased age[odds ratio(OR):1.20 per decade,95%confidence interval(CI):1.08-1.33](P<0.001),longer surgery duration(OR:1.15 per additional hour,95%CI:1.05-1.26)(P<0.01),and greater blood loss(OR:1.18 per 250-mL increment,95%CI:1.06-1.32)(P<0.01).A novel finding was the association of arterial blood Ca^(2+)<1.05 mmol/L with IPH(OR:2.03,95%CI:1.65-2.50)(P<0.001).CONCLUSION IPH during PD is independently associated with older age,prolonged surgery,increased blood loss,and lower plasma Ca^(2+). 展开更多
关键词 Risk factors PANCREATICODUODENECTOMY Perioperative period Intraoperative persistent hypotension Retrospective cohort study
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Enhancing predictive accuracy in hypertriglyceridemia-induced acute pancreatitis:Role of red cell distribution width and prospective studies
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作者 Shi-Yan Zhang 《World Journal of Clinical Cases》 SCIE 2024年第20期4452-4454,共3页
This letter addresses the study titled“Red cell distribution width:A predictor of the severity of hypertriglyceridemia-induced acute pancreatitis”by Lv et al published in the World Journal of Experimental Medicine.T... This letter addresses the study titled“Red cell distribution width:A predictor of the severity of hypertriglyceridemia-induced acute pancreatitis”by Lv et al published in the World Journal of Experimental Medicine.The study offers a valuable analysis of red cell distribution width(RDW)as a predictive marker for persistent organ failure in patients with hypertriglyceridemia-induced acute pancreatitis.The study results suggest that RDW,combined with the Bedside Index for Severity in Acute Pancreatitis score,could enhance the predictive accuracy for severe outcomes.Further investigation into the role of RDW in different severities of acute pancreatitis is recommended.Additionally,the need for large-scale and multicenter prospective studies to validate these findings is emphasized. 展开更多
关键词 Red cell distribution width Hypertriglyceridemia-induced acute pancreatitis Persistent organ failure Predictive marker Letter to the Editor COMMENTARY
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