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Persistent accumulation of therapy-induced senescent cells:an obstacle to long-term cancer treatment efficacy
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作者 Jingjing Luo Tongxu Sun +5 位作者 Zhenghui Liu Yangfan Liu Junjiang Liu Shimeng Wang Xueke Shi Hongmei Zhou 《International Journal of Oral Science》 2025年第6期735-755,共21页
In the ever-evolving landscape of cancer therapy,while cancer treatments such as chemotherapy,radiotherapy,and targeted therapy aim to eradicate malignant cells,they also inadvertently trigger cellular senescence in b... In the ever-evolving landscape of cancer therapy,while cancer treatments such as chemotherapy,radiotherapy,and targeted therapy aim to eradicate malignant cells,they also inadvertently trigger cellular senescence in both cancerous and microenvironmental tissues.Therapy-induced senescence(TIS)can act as a barrier against tumor growth by halting cell proliferation in the short term,but the long-term persistence of therapy-induced senescent(TISnt)cells may pose a significant challenge in cancer management.Their distinct characteristics,like senescence-associated secretory phenotype(SASP),metabolic dysregulation,and immune evasion,make them exhibit remarkable heterogeneity to orchestrate the tumor microenvironment(TME),resulting in therapy resistance.However,how these TISnt cells functioning differently in cancer progression,and the intricate mechanisms by which they remodel the senescence-associated immunosuppressive microenvironment present challenges for improving anticancer therapy.Therefore,this review summarizes the heterogeneous TISnt cell phenotypes contributing to an accumulated senescent state,outlines their multidimensional interactions in the senescent microenvironment,and discusses current senescence-targeting strategies.Building on the current understanding of TIS,we propose potential avenues for improving TIS-targeting methodologies in the context of head and neck cancer,a representative heterogeneous malignancy,which can substantially enhance the efficacy of the“one-two punch”sequential treatment approach for head and neck cancer. 展开更多
关键词 persistent accumulation of therapy-induced senescent cells an obstacle to long-term cancer treatment efficacy
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Control efficacy and persistence of fluopyram dust against pine wilt disease
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作者 Yajie Guo Jiayi Ma +5 位作者 Mingqing Weng Rebeca Carballar-Lejarazú Wenlong Jiao Jieqin Wu Feiping Zhang Songqing Wu 《Journal of Forestry Research》 2025年第4期205-214,共10页
The effectiveness of fluopyram suspension concentrate against pine wilt disease(PWD)is limited by spraying efficiency and water dependence.A traditional dust formulation with strong dispersibility can overcome these s... The effectiveness of fluopyram suspension concentrate against pine wilt disease(PWD)is limited by spraying efficiency and water dependence.A traditional dust formulation with strong dispersibility can overcome these shortcomings.However,its efficacy against PWD remains uncertain.This study evaluated the translocation of fluopyram dust within tree tissues,soil and water degradation,and its effective control against PWD.Nursery tests showed effective prevention;field tests showed dust absorption and translocation into pine tissues.Thirty days following application,residual concentrations in soil were low at 0.09 mg kg^(−1);no detectable residues were found in water samples.Three years after applying fluopyram,its effectiveness increased to approximately 87%.Based on this study,fluopyram had a half-life of 346 d with persistence lasting up to three years.This provides valuable insight for managing PWD through dust applications. 展开更多
关键词 Pine wilt disease Fluopyram Dust formulation EFFICACY persistence
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Identification and Prediction of Key Technologies in Ginsenosides Based on Genetic Knowledge Persistence Algorithm
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作者 Li Qian Zhang Wenfeng Yuan Hongmei 《Asian Journal of Social Pharmacy》 2025年第1期68-79,共12页
Objective To study the key technologies in the field of ginsenosides and to offer a guide for the future development ginsenosides through the main path identification method based on genetic knowledge persistence algo... Objective To study the key technologies in the field of ginsenosides and to offer a guide for the future development ginsenosides through the main path identification method based on genetic knowledge persistence algorithm(GKPA).Methods The global ginsenoside invention authorized patents were used as the data source to construct a ginsenoside patent self-citation network,and to identify high knowledge persistent patents(HKPP)of ginsenoside technology based on the GKPA,and extract its high knowledge persistence main path(HKPMP).Finally,the genetic forward and backward path(GFBP)was used to search the nodes on the main path,and draw the genetic forward and backward main path(GFBMP)of ginsenoside technology.Results and Conclusion The algorithm was applied to the field of ginsenosides.The research results show the milestone patents in ginsenosides technology and the main evolution process of three key technologies,which points out the future direction for the technological development of ginsenosides.The results obtained by this algorithm are more interpretable,comprehensive and scientific. 展开更多
关键词 ginsenoside genetic knowledge persistence algorithm(GKPA) high knowledge persistence patent(HKPP) genetic forward and backward path(GFBP) main path analysis
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Grid-growth method for the reconstruction of 3D rock joints with arbitrary joint roughness and persistence
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作者 Hanyu CHEN Peng GUO +1 位作者 Guangyao LI Lifeng FAN 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 2025年第5期393-406,共14页
We present a grid-growth method to reconstruct 3D rock joints with arbitrary joint roughness and persistence.In the first step of this workflow,the joint model is divided into uniform grids.Then by adjusting the posit... We present a grid-growth method to reconstruct 3D rock joints with arbitrary joint roughness and persistence.In the first step of this workflow,the joint model is divided into uniform grids.Then by adjusting the positions of the grids,the joint morphology can be modified to construct models with desired joint roughness and persistence.Accordingly,numerous joint models with different joint roughness and persistence were built.The effects of relevant parameters(such as the number,height,slope of asperities,and the number,area of rock bridges)on the joint roughness coefficient(JRC)and joint persistence were investigated.Finally,an artificially split joint was reconstructed using the method,and the method's accuracy was evaluated by comparing the JRC of the models with that of the artificially split joint.The results showed that the proposed method can effectively control the JRC of joint models by adjusting the number,height,and slope of asperities.The method can also modify the joint persistence of joint models by adjusting the number and area of rock bridges.Additionally,the JRC of models obtained by our method agrees with that of the artificially split surface.Overall,the method demonstrated high accuracy for 3D rock joint reconstruction. 展开更多
关键词 3D rock joint reconstruction Joint roughness Joint persistence ASPERITY Rock bridge
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Subtypes and corneal astigmatism in pediatric persistent fetal vasculature
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作者 Shao-Hua Zhang Ning Lyu +2 位作者 Ying-Ying Hong Yi Lu Ying-Hong Ji 《International Journal of Ophthalmology(English edition)》 2026年第2期333-338,共6页
AIM:To characterize the distribution of persistent fetal vasculature(PFV)subtypes and to evaluate corneal astigmatism(CA)in children with unilateral PFV.METHODS:The medical records of patients diagnosed with PFV betwe... AIM:To characterize the distribution of persistent fetal vasculature(PFV)subtypes and to evaluate corneal astigmatism(CA)in children with unilateral PFV.METHODS:The medical records of patients diagnosed with PFV between January 2014 and August 2021 were retrospectively reviewed.Corneal keratometry parameters were measured using IOLMaster or a handheld keratometer.Differences in CA between the affected and fellow eyes were analyzed in 52 unilateral PFV patients with available examination data.RESULTS:Totally 133 patients diagnosed with PFV were retrospectively reviewed.The male-to-female ratio was 73/60.Median age at surgery was 38.03mo(interquartile range 58.27mo).Among the PFV patients,32(24.06%)had anterior PFV,2(1.50%)had posterior PFV,and 99(74.44%)had combined anterior-posterior PFV.Mild combined PFV was the most common subtype.In unilateral PFV cases,the mean CA in the affected eye was 2.29±1.11 D,and 59.62%(31 eyes)had CA≥2.0 D.The mean CA in the affected eyes was significantly higher than in the fellow eyes(1.37±0.77 D;P<0.001).Among PFV-affected eyes with CA≥2.0 D,the steepest corneal meridian was vertically oriented in 30 cases(96.77%),while only 1 case(3.23%)had the steepest meridian oriented horizontally.CONCLUSION:In children with unilateral PFV,CA is significantly higher in the affected eyes than in the fellow eyes,and the steepest corneal meridian was predominantly oriented vertically. 展开更多
关键词 persistent fetal vasculature corneal astigmatism corneal keratometry children
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Long-term creep of Beishan granite under uniaxial compression
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作者 Chunping Wang Xingguang Zhao +4 位作者 Jianfeng Liu Haiyang Zhang Liang Chen Hongsu Ma Ju Wang 《International Journal of Mining Science and Technology》 2026年第1期79-93,共15页
Investigations into the long-term creep behavior of Beishan granite in uniaxial compression were conducted.Four levels of axial stress(60,70,87,and 95 MPa)were applied to rock specimens.Contrasting with earlier resear... Investigations into the long-term creep behavior of Beishan granite in uniaxial compression were conducted.Four levels of axial stress(60,70,87,and 95 MPa)were applied to rock specimens.Contrasting with earlier research,the long-term creep data in this work present a substantial advancement in the time dimension.Except for the sample subjected to 60 MPa axial loading,which did not fail after a loading duration of 1650 d,the specimens under the other three stresses all failed after sustained constant loading durations of 1204,1023,and 839 d,respectively.A lower envelope of driving stress-ratio for crystalline rocks was obtained,tending towards approximately 0.45 over an infinite time scale.According to the experimental results,as axial stress increases,both the axial strain accumulated in the transient creep process and the strain rate associated with steady-state creep deformation increase exponentially;however,the share of steady-state creep strain remains nearly constant at about82.53%.A novel damage-based creep model was put forward.It provides an enhanced depiction of the comprehensive creep process in rocks,notably improving the accuracy in forecasting the accelerated creep phase,which significantly impacts the long-term stability of engineering structures. 展开更多
关键词 long-term strength Creep model DAMAGE Creep behavior
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Potential impacts of invasive mussels on long-term carbonate chemistry changes in Lake Michigan
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作者 Chunqi SHEN Jeremy MTESTA Yang SONG 《Journal of Oceanology and Limnology》 2026年第1期125-136,共12页
While oceanic and coastal acidification has gained increased attention,long-term pH trends and their drivers in large freshwater systems remain poorly understood.The Laurentian Great Lakes are the world’s largest fre... While oceanic and coastal acidification has gained increased attention,long-term pH trends and their drivers in large freshwater systems remain poorly understood.The Laurentian Great Lakes are the world’s largest freshwater system,and in many ways resemble marine ecosystems.However,unlike the open ocean and coastal waters where pH has declined due to rising atmospheric CO_(2),no significant pH trends have been observed in the Laurentian Great Lakes,despite significant ecosystem changes driven partly by the invasion of dreissenid mussels.This study examined 41 years of field observations from Lake Michigan to investigate the long-term carbonate chemistry dynamics.Observational results revealed substantial declines in both total alkalinity(TA)and dissolved inorganic carbon(DIC)over the four decades.Mussel shell calcification emerged as the primary mechanism behind these declines,accounting for 97%and 47%of the observed changes in TA and DIC,respectively,lowering water column pH by 0.24 units.Elevated carbon accumulation in soft mussel tissues,coupled with long-term changes in the air-water pCO_(2)gradient during summer,significantly contributed to long-term DIC variations,explaining 18%and 28%of the lake-wide DIC loss.These two mechanisms also resulted in an overall pH increase of 0.09 and 0.12 units,largely offsetting the calcification-driven pH decrease.These findings bridge a gap in acidification research for large freshwater systems and provide valuable insights for comprehensive lake-wide management strategies. 展开更多
关键词 carbonate chemistry freshwater acidification invasive mussel Lake Michigan long-term trend
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Long-term stability of graphene sheets as water lubricating additives
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作者 Zhaoxiang Zhang Runhua Qiu +3 位作者 Hongling Qin Zhiying Ren Xiaohong Jia Fei Guo 《Chinese Journal of Mechanical Engineering》 2026年第1期356-369,共14页
Micron-sized graphene sheets have been introduced as additives to enhance the lubricating capabilities of water.The tribological characteristics of the lubricants after preparation and storage for 6 months were system... Micron-sized graphene sheets have been introduced as additives to enhance the lubricating capabilities of water.The tribological characteristics of the lubricants after preparation and storage for 6 months were systematically analyzed.Results indicated that the friction coefficient and wear volume of the tribo-pair were reduced through the incorporation of a certain concentration of graphene sheets,and also have long-term storage stability.Notably,under the experimental conditions,a 0.2%mass concentration of graphene in the aqueous lubricant exhibited exceptional tribological performance and long-term storage stability,achieving an 80%reduction in friction coefficient and a 78%decrease in wear volume with a 14000-cycle friction test.Wear morphology analysis indicated that after adding graphene sheets to the aqueous solution,micro-plastic deformation occurs on the worn surface of the steel plate.The wear profile of the GCr15 counter ball changes from a circular profile to a rectangular-like profile.The main reason is that the graphene sheets in the aqueous solution can enter the contact interface during the friction process,hindering direct contact between the friction pair.The study prov-ides a simple method to improve the tribological properties of aqueous solutions stably for engineering applica-tions. 展开更多
关键词 Tribological behaviors GRAPHENE Water-based lubricant Wear morphology analysis long-term storage
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Analysis of Long-term Prognosis and Cosmetic Outcomes of Breast-conserving Surgery Combined with Sentinel Lymph Node Biopsy for Early-stage Breast Cancer
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作者 Yuedong Zhang 《Proceedings of Anticancer Research》 2026年第1期101-108,共8页
Objective:To investigate the long-term prognosis and postoperative cosmetic outcomes of breast-conserving surgery combined with sentinel lymph node biopsy in patients with early-stage breast cancer,providing a referen... Objective:To investigate the long-term prognosis and postoperative cosmetic outcomes of breast-conserving surgery combined with sentinel lymph node biopsy in patients with early-stage breast cancer,providing a reference for the selection of clinical treatment plans.Methods:A retrospective analysis was conducted on the clinical data of 68 patients with early-stage breast cancer admitted from January 2022 to December 2025.Based on the surgical approach,patients were divided into an observation group(breast-conserving surgery+sentinel lymph node biopsy)and a control group(other surgical methods such as modified radical mastectomy/total mastectomy).Clinical and pathological characteristics,incidence of postoperative complications,follow-up prognosis,and satisfaction with cosmetic outcomes were compared between the two groups.Results:Among the 68 patients,41 were in the observation group and 27 in the control group.The average age of patients in the observation group was(54.32±8.15)years,while that in the control group was(62.45±9.76)years.The average tumor size in the observation group was(1.86±0.72)cm,compared to(3.21±1.45)cm in the control group.The incidence of postoperative complications in the observation group was 9.76%,significantly lower than that in the control group at 33.33%(P<0.05).The 6-month disease-free survival rate was 95.12%in the observation group and 88.89%in the control group,with no statistically significant difference between the two groups(P>0.05).The excellent and good rate of cosmetic outcomes in the observation group was 87.80%,significantly higher than that in the control group at 29.63%(P<0.05).Conclusion:Breast-conserving surgery combined with sentinel lymph node biopsy for early-stage breast cancer can achieve long-term prognostic outcomes comparable to those of traditional radical surgery,with the advantages of fewer postoperative complications and superior cosmetic results.This approach is worthy of clinical promotion and application,particularly for early-stage breast cancer patients who have a demand for preserving breast morphology. 展开更多
关键词 Early-stage breast cancer Breast-conserving surgery Sentinel lymph node biopsy long-term prognosis Cosmetic results
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Long-term outcomes following lens extraction surgery in acute primary angle closure
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作者 Yi-Ning Guo Jing Ding +3 位作者 Hao-Ran Ai Xin-Zuo Zhou Xue-Min Li Chun Zhang 《International Journal of Ophthalmology(English edition)》 2026年第2期281-290,共10页
AIM:To investigate the long-term outcomes in acute primary angle closure(APAC)patients treated with lens extraction(LE)surgery and to identify risk factors for glaucomatous optic neuropathy(GON).METHODS:In this longit... AIM:To investigate the long-term outcomes in acute primary angle closure(APAC)patients treated with lens extraction(LE)surgery and to identify risk factors for glaucomatous optic neuropathy(GON).METHODS:In this longitudinal observational study,detailed medical histories of APAC patients and comprehensive ophthalmic examinations at final followup were collected.Logistic regression analysis was performed to identify predictors of blindness.Univariate and multivariate linear regression analyses were conducted to determine risk factors associated with visual outcomes.RESULTS:This study included 39 affected eyes of 31 subjects(26 females)with an average age of 74.1±8.0y.At 6.7±4.2y after APAC attack,2(5.7%)eyes had bestcorrected visual acuity(VA)worse than 3/60.Advanced glaucomatous visual field loss was observed in 15(39.5%)affected eyes and 5(25.0%)fellow eyes.Nine affected eyes(23.7%)had GON,and 11(28.9%)were blind.Six(15.4%)affected eyes and 2(9.1%)fellow eyes had suspicious progression.A significantly higher blindness rate in factory workers compared to office workers.Logistic regression identified that worse VA at attack(OR 10.568,95%CI 1.288-86.695;P=0.028)and worse early postoperative VA(OR 13.214,95%CI 1.157-150.881;P=0.038)were risk factors for blindness.Multivariate regression showed that longer duration of elevated intraocular pressure(P=0.004)and worse early postoperative VA(P=0.009)were associated with worse visual outcomes.CONCLUSION:Despite LE surgery,some APAC patients experience continued visual function deterioration.Lifelong monitoring is necessary.Target pressure and progression rates should be re-evaluated during follow-up. 展开更多
关键词 acute primary angle closure lens extraction surgery long-term follow-up visual impairment glaucomatous optic neuropathy
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Long-term manure amendment enhances N_(2)O emissions from acidic soil by alleviating acidification and increasing nitrogen mineralization
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作者 Lei Wu Jing Hu +4 位作者 Muhammad Shaaban Jun Wang Kailou Liu Minggang Xu Wenju Zhang 《Journal of Integrative Agriculture》 2026年第1期262-272,共11页
Long-term manure application has the potential to alleviate soil acidification, and increase carbon sequestration and nutrient availability, thus improving cropland fertility. However, the mechanisms behind greenhouse... Long-term manure application has the potential to alleviate soil acidification, and increase carbon sequestration and nutrient availability, thus improving cropland fertility. However, the mechanisms behind greenhouse gas N_(2)O emissions from acidic soil mediated by long-term manure application remain poorly understood. Herein, we investigated N_(2)O emission and its linkage with gross N mineralization and nitrification rates, as well as nitrifying and denitrifying microbes in an acidic upland soil subjected to 36-year fertilization treatments, including an unfertilized control(CK), inorganic fertilizer(F), 2× rate of inorganic fertilizer(2F), manure(M), and the combination of inorganic fertilizer and manure(FM) treatments. Compared to the CK treatment(1.34 μg N kg^(-1) d^(-1)), fertilization strongly increased N_(2)O emissions by 34-fold on average, with more pronounced increases in the manure-amendment(10.6-169 μg N kg^(-1) d^(-1)) than those in the inorganic fertilizer treatments(3.26-5.51 μg N kg^(-1) d^(-1)). The manure amendment-stimulated N_(2)O emissions were highly associated with increased soil pH, mean weight diameter of soil aggregates, substrate availability(e.g., particulate organic carbon, NO_(3)^(-)and available phosphorus), gross N mineralization rates, denitrifier abundances and the(nirK+nirS)/nosZ ratio. These findings suggest that the increased N_(2)O emissions primarily resulted from alleviated acidification, increased substrate availability and improved soil structure, thus enhancing microbial N mineralization and favoring N_(2)O^(-)producing denitrifiers over N_(2)O consumers. Moreover, ammonia-oxidizing bacteria(AOB) rather than ammonia-oxidizing archaea(AOA) positively correlated with soil NO_(3)^(-)concentration and N_(2)O emissions, indicating that nitrification indirectly contributed to N_(2)O production by supplying NO_(3)^(-)for denitrification. Collectively, manure amendment potentially stimulates N_(2)O emissions, primarily resulting from alleviated soil acidification and increased substrate availability, thus enhancing N mineralization and denitrifier-mediated N_(2)O production. Our findings suggest that consideration should be given to the greenhouse gas budgets of agricultural ecosystems when applying manure for managing the pH and fertility of acidic soils. 展开更多
关键词 long-term manure amendment N_(2)O emission nitrogen mineralization denitrification (nirK+nirS)/nosZ
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State Space Guided Spatio-Temporal Network for Efficient Long-Term Traffic Prediction
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作者 Guangyu Huo Chang Su +2 位作者 Xiaoyu Zhang Xiaohui Cui Lizhong Zhang 《Computers, Materials & Continua》 2026年第2期1242-1264,共23页
Long-term traffic flow prediction is a crucial component of intelligent transportation systems within intelligent networks,requiring predictive models that balance accuracy with low-latency and lightweight computation... Long-term traffic flow prediction is a crucial component of intelligent transportation systems within intelligent networks,requiring predictive models that balance accuracy with low-latency and lightweight computation to optimize trafficmanagement and enhance urban mobility and sustainability.However,traditional predictivemodels struggle to capture long-term temporal dependencies and are computationally intensive,limiting their practicality in real-time.Moreover,many approaches overlook the periodic characteristics inherent in traffic data,further impacting performance.To address these challenges,we introduce ST-MambaGCN,a State-Space-Based Spatio-Temporal Graph Convolution Network.Unlike conventionalmodels,ST-MambaGCN replaces the temporal attention layer withMamba,a state-space model that efficiently captures long-term dependencies with near-linear computational complexity.The model combines Chebyshev polynomial-based graph convolutional networks(GCN)to explore spatial correlations.Additionally,we incorporate a multi-temporal feature capture mechanism,where the final integrated features are generated through the Hadamard product based on learnable parameters.This mechanism explicitly models shortterm,daily,and weekly traffic patterns to enhance the network’s awareness of traffic periodicity.Extensive experiments on the PeMS04 and PeMS08 datasets demonstrate that ST-MambaGCN significantly outperforms existing benchmarks,offering substantial improvements in both prediction accuracy and computational efficiency for long-term traffic flow prediction. 展开更多
关键词 State space model long-term traffic flow prediction graph convolutional network multi-time scale analysis emerging applications at intelligent networks
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Persistence of hepatitis B vaccine immune protection and response to hepatitis B booster immunization 被引量:15
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作者 LI Hui 1, LI Rong Cheng 2, LIAO Su Su 1, YANG Jin Ye 2, ZENG Xian Jia 1 and WANG Shu Sheng 2 《World Journal of Gastroenterology》 SCIE CAS CSCD 1998年第6期38-41,共4页
AbstractAIMToidentifythepersistenceofimmuneprotectionofChinamade,plasmaderivedhepatitisBvaccineafterinfancyi... AbstractAIMToidentifythepersistenceofimmuneprotectionofChinamade,plasmaderivedhepatitisBvaccineafterinfancyimmunizationandt... 展开更多
关键词 HEPATITIS B vaccines IMMUNE PROTECTION persistence BOOSTER IMMUNIZATION
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PERSISTENCE AND GLOBAL STABILITY FOR A THREE-SPECIES RATIO-DEPENDENT PREDATOR-PREY SYSTEM WITH TIME DELAYS IN TWO-PATCH ENVIRONMENTS 被引量:12
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作者 徐瑞 陈兰荪 《Acta Mathematica Scientia》 SCIE CSCD 2002年第4期533-541,共9页
A three-species ratio-dependent predator-prey diffusion model with time delays is investigated. It is shown that the system is uniformly persistent under some appropriate conditions, and sufficient conditions axe obta... A three-species ratio-dependent predator-prey diffusion model with time delays is investigated. It is shown that the system is uniformly persistent under some appropriate conditions, and sufficient conditions axe obtained for the global stability of the positive equilibrium of the system. 展开更多
关键词 time delay diffusion uniform persistence global asymptotic stability
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PERSISTENCE AND PERIODIC ORBITS FOR TWO-SPECIES NON-AUTONOMOUS DIFFUSION LOTKA-VOLTERRA MODELS 被引量:4
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作者 ChenFengde 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2004年第4期359-366,共8页
A non-autonomous competing system is investigated in this paper,where the species x can diffuse between two patches of a heterogeneous environment with barriers between patches,but for species y,the diffusion does not... A non-autonomous competing system is investigated in this paper,where the species x can diffuse between two patches of a heterogeneous environment with barriers between patches,but for species y,the diffusion does not involve a barrier between patches,further it is assumed that all the parameters are time dependent.It is shown that the system can be made persistent under some appropriate conditions.Moreover,sufficient conditions that guarantee the existence of a unique positive periodic orbit which is globally asymptotic stable are derived. 展开更多
关键词 persistence DIFFUSION periodic orbits global stability.
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UNIQUE CONTINUATION AND PERSISTENCE PROPERTIES OF SOLUTIONS OF THE 2-COMPONENT DEGASPERIS-PROCESI EQUATIONS 被引量:7
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作者 付英 屈长征 《Acta Mathematica Scientia》 SCIE CSCD 2012年第2期652-662,共11页
In this article, the unique continuation and persistence properties of solutions of the 2-component Degasperis-Procesi equations are discussed. It is shown that strong solutions of the 2-component Degasperis-Procesi e... In this article, the unique continuation and persistence properties of solutions of the 2-component Degasperis-Procesi equations are discussed. It is shown that strong solutions of the 2-component Degasperis-Procesi equations, initially decaying exponentially together with its spacial derivative, must be identically equal to zero if they also decay exponentially at a later time. 展开更多
关键词 2-component Degasperis-Procesi equation unique continuation property persistence property
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PERSISTENCE AND THE GLOBAL DYNAMICS OF THE POSITIVE SOLUTIONS FOR A RATIODEPENDENT PREDATOR-PREY SYSTEM WITH A CROWDING TERM IN THE PREY EQUATION 被引量:3
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作者 曾宪忠 顾永耕 《Acta Mathematica Scientia》 SCIE CSCD 2016年第3期689-703,共15页
This paper deals with the global dynamical behaviors of the positive solutions for a parabolic type ratio-dependent predator-prey system with a crowding term in the prey equation, where it is assumed that the coeffici... This paper deals with the global dynamical behaviors of the positive solutions for a parabolic type ratio-dependent predator-prey system with a crowding term in the prey equation, where it is assumed that the coefficient of the functional response is less than the coefficient of the intrinsic growth rates of the prey species. We demonstrated some special dynamical behaviors of the positive solutions of this system which the persistence of the coexistence of two species can be obtained when the crowding region in the prey equation only is designed suitably. Furthermore, we can obtain that under some conditions, the unique positive steady state solution of the system is globally asymptotically stable. 展开更多
关键词 ratio-dependent predator-prey system crowding effect persistence global stability
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PERSISTENCE IN A THREE SPECIES LOTKA-VOLTERRA NONPERIODIC PREDATOR-PREY SYSTEM 被引量:2
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作者 张银萍 孙继涛 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2000年第8期879-884,共6页
The predator-prey model for three species in which the right-hand sides are nonperiodic functions in time were considered, It's proved that the model is persistent under appropriate conditions.
关键词 persistence predator-prey system nonperiodic
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PERSISTENCE AND EXTINCTION OF A STOCHASTIC LOGISTIC MODEL WITH DELAYS AND IMPULSIVE PERTURBATION 被引量:2
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作者 卢春 丁效华 《Acta Mathematica Scientia》 SCIE CSCD 2014年第5期1551-1570,共20页
A stochastic logistic model with delays and impulsive perturbation is proposed and investigated. Sufficient conditions for extinction are established as well as nonpersistence in the mean, weak persistence and stochas... A stochastic logistic model with delays and impulsive perturbation is proposed and investigated. Sufficient conditions for extinction are established as well as nonpersistence in the mean, weak persistence and stochastic permanence. The threshold between weak persistence and extinction is obtained. Furthermore, the theoretical analysis results are also derivated with the help of numerical simulations. 展开更多
关键词 logistic model white noise DELAY persistence impulsive perturbation
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Persistence and growth of faecal culturable bacterial indicators in water column and sediments of Vidy Bay,Lake Geneva,Switzerland 被引量:2
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作者 POTE John HALLER Laurence +3 位作者 KOTTELAT Régis SASTRE Vincent ARPAGAUS Philippe WILDI Walter 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2009年第1期62-69,共8页
The aims of this study was to investigate the persistence and the growth of culturable bacterial indicators (CBI) including total coliforms (TC) and faecal coliforms represented by Escherichia coli, enterococcus ... The aims of this study was to investigate the persistence and the growth of culturable bacterial indicators (CBI) including total coliforms (TC) and faecal coliforms represented by Escherichia coli, enterococcus (ENT), and aerobic mesophilic bacteria (AMB) in the surface sediments and the water column of Vidy Bay fLake Geneva, City of Lausanne, Switzerland). The study was carded out for 60 d using microcosms containing Sewage Treatment Plant (STP) effluent and nonsterile water without CBI, as well as contaminated and non-contaminated sediments. The effects of water temperature and of organic matter associated with sediments on the survival of CBI in the sediments and the water column were observed. The number of CBI colonies in the contaminated sediments of Vidy Bay and in the STP effluent was almost identical in the order of 10^5-10^7, 10^4-10^6, 10^5-10^5, and 10^4-10^7 CFU/100 g sediment or/100 mL water for TC, E. coli, ENT, and AMB respectively. A degradation of CBI was observed in the sediments where organic mater content was low and in the water column at a temperature of 10℃ after 5 d of experimentation. In addition, a growth of CBI was observed in the sediment which is rich in organic matter at 20℃. The results of this study indicate: (1) the higher concentrations of the CBI observed in different points in the water column of Vidy Bay may not be explained only by the recent contribution of the three potential sources of the Bay contamination including STP and the Chamberonne and Flon Rivers, but also by the persistence, removal from sediment and multiplication of CBI in the sediment and water column; (2) the sediment of Vidy Bay constitute a reservoir of CBI and can even support their growth; and (3) the CBI not only survive in sediments, but also can be remobilized and increased in the water column, therefore, it become a permanent microbiological pollution in Vidy Bay. 展开更多
关键词 Lake Geneva faecal pollution persistence MULTIPLICATION human health risk
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