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New algorithm of mining frequent closed itemsets
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作者 张亮 任永功 付玉 《Journal of Southeast University(English Edition)》 EI CAS 2008年第3期335-338,共4页
A new algorithm based on an FC-tree (frequent closed pattern tree) and a max-FCIA (maximal frequent closed itemsets algorithm) is presented, which is used to mine the frequent closed itemsets for solving memory an... A new algorithm based on an FC-tree (frequent closed pattern tree) and a max-FCIA (maximal frequent closed itemsets algorithm) is presented, which is used to mine the frequent closed itemsets for solving memory and time consuming problems. This algorithm maps the transaction database by using a Hash table,gets the support of all frequent itemsets through operating the Hash table and forms a lexicographic subset tree including the frequent itemsets.Efficient pruning methods are used to get the FC-tree including all the minimum frequent closed itemsets through processing the lexicographic subset tree.Finally,frequent closed itemsets are generated from minimum frequent closed itemsets.The experimental results show that the mapping transaction database is introduced in the algorithm to reduce time consumption and to improve the efficiency of the program.Furthermore,the effective pruning strategy restrains the number of candidates,which saves space.The results show that the algorithm is effective. 展开更多
关键词 frequent itemsets frequent closed itemsets minimum frequent closed itemsets maximal frequent closed itemsets frequent closed pattern tree
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Induced neural stem cells regulate microglial activation through Akt-mediated upregulation of CXCR4 and Crry in a mouse model of closed head injury 被引量:1
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作者 Mou Gao Qin Dong +3 位作者 Dan Zou Zhijun Yang Lili Guo Ruxiang Xu 《Neural Regeneration Research》 SCIE CAS 2025年第5期1416-1430,共15页
Microglial activation that occurs rapidly after closed head injury may play important and complex roles in neuroinflammation-associated neuronal damage and repair.We previously reported that induced neural stem cells ... Microglial activation that occurs rapidly after closed head injury may play important and complex roles in neuroinflammation-associated neuronal damage and repair.We previously reported that induced neural stem cells can modulate the behavior of activated microglia via CXCL12/CXCR4 signaling,influencing their activation such that they can promote neurological recovery.However,the mechanism of CXCR4 upregulation in induced neural stem cells remains unclear.In this study,we found that nuclear factor-κB activation induced by closed head injury mouse serum in microglia promoted CXCL12 and tumor necrosis factor-αexpression but suppressed insulin-like growth factor-1 expression.However,recombinant complement receptor 2-conjugated Crry(CR2-Crry)reduced the effects of closed head injury mouse serum-induced nuclear factor-κB activation in microglia and the levels of activated microglia,CXCL12,and tumor necrosis factor-α.Additionally,we observed that,in response to stimulation(including stimulation by CXCL12 secreted by activated microglia),CXCR4 and Crry levels can be upregulated in induced neural stem cells via the interplay among CXCL12/CXCR4,Crry,and Akt signaling to modulate microglial activation.In agreement with these in vitro experimental results,we found that Akt activation enhanced the immunoregulatory effects of induced neural stem cell grafts on microglial activation,leading to the promotion of neurological recovery via insulin-like growth factor-1 secretion and the neuroprotective effects of induced neural stem cell grafts through CXCR4 and Crry upregulation in the injured cortices of closed head injury mice.Notably,these beneficial effects of Akt activation in induced neural stem cells were positively correlated with the therapeutic effects of induced neural stem cells on neuronal injury,cerebral edema,and neurological disorders post–closed head injury.In conclusion,our findings reveal that Akt activation may enhance the immunoregulatory effects of induced neural stem cells on microglial activation via upregulation of CXCR4 and Crry,thereby promoting induced neural stem cell–mediated improvement of neuronal injury,cerebral edema,and neurological disorders following closed head injury. 展开更多
关键词 Akt signaling cerebral edema closed head injury Crry CXCR4 induced neural stem cell MICROGLIA NEUROINFLAMMATION
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Construction of hard carbon with abundant closed ultra-micropores via a pre-oxidation strategy for high-efficiency sodium storage in the low potential plateau 被引量:1
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作者 Wenbo Hou Lili Ma +6 位作者 Zhiyuan Liu Yiming Hu Wenxing Miao Bo Tao Kanjun Sun Hui Peng Guofu Ma 《Journal of Energy Chemistry》 2025年第6期65-75,I0003,共12页
Rationally regulating the porosity of hard carbon(HC),especially the closed pores matching the low potential plateau and the ultra-microporous structure suitable for Na+embedding,has been shown to be the key to improv... Rationally regulating the porosity of hard carbon(HC),especially the closed pores matching the low potential plateau and the ultra-microporous structure suitable for Na+embedding,has been shown to be the key to improving the sodium storage performance and initial coulombic efficiency(ICE).However,the preparation of such HC materials with specific pore structures still faces great challenges.Herein,a simple pre-oxidation strategy is employed to construct abundant closed ultra-microporous structures in soy protein powder-derived HC material,achieving a significant improvement in its ICE and platform capacity.The pre-oxidation process promotes the cross-linking degree of the soy protein,thereby hindering the directional growth of graphite domains during the carbonization process.The optimized HC exhibits ultra-high platform capacity(329 mAh g^(-1))and considerable energy density(148.5 Wh kg^(-1)).Based on the ex-situ Raman and X-ray photoelectron spectroscopy characterization results,the excellent sodium storage capacity of the HC material is attributed to the synergistic effect of adsorption-intercalation/filling.The presented work provides novel insights into the synthesis of other biomass-derived HC materials with abundant closed ultra-micro pores. 展开更多
关键词 Pre-oxidation strategy closed ultra-micropores Low potential plateau Sodium-ion storage
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Multiplicity and Stability of Closed Characteristics on Compact Convex Hypersurfaces in R^(2n)
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作者 WANG Wei 《数学进展》 北大核心 2025年第4期673-686,共14页
A survey of recent progress on the multiplicity and stability problems for closed characteristics on compact convex hypersurfaces in R^(2n) is given.
关键词 compact convex hypersurface closed characteristic Hamiltonian system Morse theory index iteration theory
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Comprehensive Understanding of Closed Pores in Hard Carbon Anode for High-Energy Sodium-Ion Batteries
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作者 Siyang Gan Yujie Huang +9 位作者 Ningyun Hong Yinghao Zhang Bo Xiong Zhi Zheng Zidong He Shengrui Gao Wentao Deng Guoqiang Zou Hongshuai Hou Xiaobo Ji 《Nano-Micro Letters》 2025年第12期679-731,共53页
Hard carbon(HC)is considered the most promising anode material for sodium-ion batteries(SIBs)due to its high costeffectiveness and outstanding overall performance.However,the amorphous and intricate microstructure of ... Hard carbon(HC)is considered the most promising anode material for sodium-ion batteries(SIBs)due to its high costeffectiveness and outstanding overall performance.However,the amorphous and intricate microstructure of HC poses significant challenges in elucidating the structure-performance relationship,which has led to persistent misinterpretations regarding the intrinsic characteristics of closed pores.An irrational construction methodology of closed pores inevitably results in diminished plateau capacity,which severely restricts the practical application of HC in high-energy-density scenarios.This review provides a systematic exposition of the conceptual framework and origination mechanisms of closed pores,offering critical insights into their structural characteristics and formation pathways.Subsequently,by correlating lattice parameters with defect configurations,the structure-performance relationships governing desolvation kinetics and sodium storage behavior are rigorously established.Furthermore,pioneering advancements in structural engineering are critically synthesized to establish fundamental design principles for the rational modulation of closed pores in HC.It is imperative to emphasize that adopting a molecular-level perspective,coupled with a synergistic kinetic/thermodynamic approach,is critical for understanding and controlling the transformation process from open pores to closed pores.These innovative perspectives are strategically designed to accelerate the commercialization of HC,thereby catalyzing the sustainable and high-efficiency development of SIBs. 展开更多
关键词 Hard carbon closed pores ANODE Sodium-ion batteries High energy density
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Loading effects of unsaturated loess considering the influence of closed gas phase
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作者 Biao Qin Xi'an Li +2 位作者 Li Wang Hao Chai Qian Liu 《Journal of Rock Mechanics and Geotechnical Engineering》 2025年第4期2416-2432,共17页
Loess is susceptible to loading effects such as significant changes in strength and volume variation caused by loading and wetting.In this study,considering the different connection states of pore water and gas in loe... Loess is susceptible to loading effects such as significant changes in strength and volume variation caused by loading and wetting.In this study,considering the different connection states of pore water and gas in loess fabric,the gas phase closure case is incorporated into a unified form of the generalized effective stress framework,introducing a damage parameter considering the effects of closed pore gas.The loading effects of unsaturated loess under wide variations in saturation are described in a unified way,and the model performance is verified by corresponding stress and hydraulic path tests.The results indicated that the collapse response involves the initial void ratio of loess,and the coupled outwards motion of the loading-collapse(LC)yield surface under loading enhances its structural strength.Suction-enhanced yield stress requires a greater"tensile stress"to counteract its structural stability.The nucleation of bubbles at high saturation causes a decrease in yield stress.The loading effect exhibits a smaller collapse behavior when the influence of closed gas is considered,whereas the suction path does not cross the LC in the stress space under hydraulic action for the same parameters,which amplifies the influence of closed gas on loess deformation. 展开更多
关键词 Unsaturated loess closed gas Generalized effective stress Loading effect Constitutive model
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The effect of a closed back cavity on air-coupled piezoelectric micromachined ultrasonic transducer performance
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作者 Yi Gong Miaojie Liu +4 位作者 Shaobo Gong Quanning Li Xuejiao Chen Wei Pang Menglun Zhang 《Nanotechnology and Precision Engineering》 2025年第3期8-17,共10页
In conventional piezoelectric micromachined ultrasonic transducers(PMUTs),the backside acoustic energy is often used inefficiently,resulting in up to half of the energy being wasted.Vacuum encapsulation can improve th... In conventional piezoelectric micromachined ultrasonic transducers(PMUTs),the backside acoustic energy is often used inefficiently,resulting in up to half of the energy being wasted.Vacuum encapsulation can improve the energy utilization efficiency,but this technique is not compatible with state-of-the-art devices such as cantilever-based PMUTs.A closed back cavity provides an alternative method for effectively utilizing the backside acoustic energy.This paper investigates the effects of a closed back cavity on PMUT performance through theoretical analysis,simulations,and experimental verification.Increasing the cavity depth produces a periodic modulation of several key PMUT metrics,such as the relative frequency deviation and quality factor.The optimal cavity depth for PMUTs that ensures a robust resonant frequency and high quality factor is defined as a function of the acoustic wavelength.A closed back cavity also provides an effective method for continuously tuning the quality factor,and thus the bandwidth,of PMUTs.This work paves the way for air-coupled PMUTs with adjustable performance for various applications. 展开更多
关键词 closed back cavity Cavity resonance Air-coupled PMUTs Performance tuning
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Visualization System for Closed Thoracic Drainage Puncture Based on Augmented Reality and Ultrafine Diameter Camera
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作者 QIN Wei WANG Shuyi +3 位作者 CHEN Xueyu ZHUANG Yiwei SHEN Yichun SHEN Yuhan 《Journal of Shanghai Jiaotong university(Science)》 2025年第3期417-424,共8页
Closed thoracic drainage can be performed using a steel-needle-guided chest tube to treat pleural effusion or pneumothorax in clinics.However,the puncture procedure during surgery is invisible,increasing the risk of s... Closed thoracic drainage can be performed using a steel-needle-guided chest tube to treat pleural effusion or pneumothorax in clinics.However,the puncture procedure during surgery is invisible,increasing the risk of surgical failure.Therefore,it is necessary to design a visualization system for closed thoracic drainage.Augmented reality(AR)technology can assist in visualizing the internal anatomical structure and determining the insertion point on the body surface.The structure of the currently used steel-needle-guided chest tube was modified by integrating it with an ultrafine diameter camera to provide real-time visualization of the puncture process.After simulation experiments,the overall registration error of the AR method was measured to be within(3.59±0.53)mm,indicating its potential for clinical application.The ultrafine diameter camera module and improved steel-needle-guided chest tube can timely reflect the position of the needle tip in the human body.A comparative experiment showed that video guidance could improve the safety of the puncture process compared to the traditional method.Finally,a qualitative evaluation of the usability of the system was conducted through a questionnaire.This system facilitates the visualization of closed thoracic drainage puncture procedure and pro-vides an implementation scheme to enhance the accuracy and safety of the operative step,which is conducive to reducing the learning curve and improving the proficiency of the doctors. 展开更多
关键词 closed thoracic drainage visualization augmented reality(AR) steel-needle-guided chest tube ultrafine diameter camera
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Closed Classes of Binary Complete Decision Tables with Many-Valued Decisions
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作者 Azimkhon Ostonov Kerven Durdymyradov Mikhail Moshkov 《Journal of Intelligent Learning Systems and Applications》 2025年第4期211-236,共26页
A binary complete decision table with many-valued decisions is a table with n attributes and 2^(n) pairwise distinct rows filled with numbers from the set{0,1}.Each row of this table is labeled with a nonempty finite ... A binary complete decision table with many-valued decisions is a table with n attributes and 2^(n) pairwise distinct rows filled with numbers from the set{0,1}.Each row of this table is labeled with a nonempty finite set of decisions.For a given row of the table,the task is to find a decision from the set of decisions attached to the row.Such tables are generalizations of Boolean functions.They can also be viewed as representations of various problems related to systems of decision rules.In this paper,we consider three types of classes of binary complete decision tables with many-valued decisions,closed with respect to removal of columns and changing of decisions.For tables from these classes,we study the relationships between the minimum weighted depth of deterministic,nondeterministic,and(for one type of classes)strongly nondeterministic decision trees and the total weight of attributes attached to columns.Note that nondeterministic decision trees and strongly nondeterministic decision trees for decision tables can be interpreted as a way of representing the two types of systems of decision rules for these tables. 展开更多
关键词 Binary Complete Decision Table closed Class Deterministic Decision Tree Nondeterministic Decision Tree Strongly Nondeterministic Decision Tree
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Closed Reduction and Minimally Invasive Fixation for the Treatment of Bilateral Displaced Posterior Pelvic Ring Disruption
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作者 Zhen Wang Zhe Xu +5 位作者 Peng-hui Xiang Mei-qi Gu Rui Zhang Hua Chen Li He Cheng-la Yi 《Current Medical Science》 2025年第1期137-145,共9页
Objective Close reduction and internal fixation have gained popularity for the treatment of pelvic fractures.However,the closed reduction of bilateral displaced posterior pelvic ring disruption is a great challenge ev... Objective Close reduction and internal fixation have gained popularity for the treatment of pelvic fractures.However,the closed reduction of bilateral displaced posterior pelvic ring disruption is a great challenge even for the most experienced surgeon.In this study,we describe in detail a novel unlocking closed reduction technique(UCRT)frame that allows strong traction for bilateral posterior pelvic ring displacement and presents preliminary clinical outcomes.Methods We retrospectively reviewed 32 patients with bilateral displaced posterior pelvic ring disruptions(AO/OTA 61-C2 and C3)who were initially treated with this technique between July 2017 and July 2022.According to the AO/OTA clas-sification,there were 9 cases(28.12%)of 61-C2,and 23 cases(71.88%)of 61-C3.There were 11 males,21 females,with an average age of 38.1 years.The interval from injury to operation was 4-27 days,with a cut-off of 12.5 days(receiver operat-ing characteristic curve).Operative time,blood loss,and postoperative radiographic findings were recorded.The functional outcomes and complications were followed.Results A total of 30(93.8%)patients achieved successful closed reduction,whereas 2 required open reduction.The success-ful closed reduction rate was 95.5%(21/22)in patients whose injury-to-operation time was less than 12.5 days.The vertical displacement percent correction of the obviously displaced hemipelvis was 70.20%±16.79%on average.The average degree of pelvic deformity correction was 64.86%±17.71%.Thirty patients were followed up for at least 12 months(12-36 months),and no complications of nonunion or redisplacement were observed.The Matta-Tornetta scoring standard revealed that the excellent(25/30)and good(4/30)rate was 96.7%.The Majeed clinical efficacy score revealed that the overall excellent and good rate was 100%.One patient had INFIX-related infection,and 2 reported numbness in the lateral thigh.The numbness was improved after INFIX removal.Conclusions This study presents an updated technique for closed reduction using a UCRT frame for bilateral posterior pelvic ring disruption,which has been shown to be effective,as indicated by excellent surgical and functional outcomes. 展开更多
关键词 Pelvic fractures Unlocking closed reduction technique Minimally invasive internal fixation
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C^(2)estimates for a class of degenerate k-Hessian equations with gradient terms on closed Hermitian manifolds
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作者 WU Hanqing XU Lu 《纯粹数学与应用数学》 2025年第1期25-45,共21页
In this article,we are concerned with the C^(2)estimates for the k-convex solutions of a class of degenerate k-Hessian equations on closed Hermitian manifolds,whose function in the right-hand side is relevant to the u... In this article,we are concerned with the C^(2)estimates for the k-convex solutions of a class of degenerate k-Hessian equations on closed Hermitian manifolds,whose function in the right-hand side is relevant to the unknown function and its gradient.We will get C^(0)estimate by promoting others′results,and get the“HMW estimate”of this equation such that the conditions of using blow-up analysis are satisfied,and the gradient estimate and second-order estimate will be obtained.Such an estimate will be helpful to study the existence for the solution of the equation. 展开更多
关键词 C^(2)estimates degenerate k-Hessian equation closed Hermitian manifold
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OPEN表和CLOSED表的合一 被引量:2
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作者 冯乃勤 王岁花 +1 位作者 郑延斌 冯国燚 《计算机工程与应用》 CSCD 北大核心 2003年第16期100-101,125,共3页
在人工智能传统的搜索方法中,一直是将OPEN表和CLOSED表分开的。这不仅增加了搜索算法的复杂性,久而久之,也许禁锢了人们的思想。文章试图改变这种状况,提出了一种与众不同的新思路,巧妙地将OPEN表和CLOSED表合二为一,减少了一些工作量... 在人工智能传统的搜索方法中,一直是将OPEN表和CLOSED表分开的。这不仅增加了搜索算法的复杂性,久而久之,也许禁锢了人们的思想。文章试图改变这种状况,提出了一种与众不同的新思路,巧妙地将OPEN表和CLOSED表合二为一,减少了一些工作量,在一定程度上降低了算法的复杂性。 展开更多
关键词 搜索 0PEN表 closed 算法复杂性
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Singular Points, Closed Orbits, Stable Manifolds and Unstable Manifolds of Second Order Autonomous Birkhoff Systems 被引量:1
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作者 陈向炜 梅凤翔 《Journal of Beijing Institute of Technology》 EI CAS 1998年第4期330-336,共7页
Aim To study singular points, closed orbits, stable manifolds and unstable manifolds of a second order autonomous Birkhoff system. Methods Qualitative methods of ordinary differential equation were used. Results and ... Aim To study singular points, closed orbits, stable manifolds and unstable manifolds of a second order autonomous Birkhoff system. Methods Qualitative methods of ordinary differential equation were used. Results and Conclusion The criteria for singular points, closed orbits and hyperbolic equilibrium points of a second order autonomous Birkhoff system are given. Moreover the stability of equilibria, stable manifolds and unstable manifolds are obtained. 展开更多
关键词 Birkhoff system singular point closed orbit stable manifold unstable manifold
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Evaluation of Two Cooling Methods for Closed Greenhouses
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作者 张敏 樊强 +1 位作者 党亚爱 薛绪掌 《Agricultural Science & Technology》 CAS 2016年第6期1475-1478,共4页
Special cooling methods are needed for normal growth of crops in closed greenhouses which permit no ventilation, especially during warm seasons. Experi- ments were designed to evaluate two cooling methods (Watergy ch... Special cooling methods are needed for normal growth of crops in closed greenhouses which permit no ventilation, especially during warm seasons. Experi- ments were designed to evaluate two cooling methods (Watergy chimney method and pool method) in a closed greenhouse in Beijing during warm seasons. Prelimi- nary results showed that average temperature at daytime (from 8:00 to 18:00) at 100 cm above ground surface in the closed greenhouse could be reduced by 8 with the Watergy chimney method. Average relative humidity fluctuated between 45% and 75% during daytime at 100 cm above ground surface within the closed greenhouse. With the pool method, average temperature was about 10 ℃ lower than that of the control greenhouse without pool at 50 cm above the ground surface. The peak temperature at 50 cm height was about 32℃ between 11:30 and 15:00 and, close to outside temperature. Temperature in this system satisfied normal growth of most crops, but relative humidity at 50 cm height were above 90% at daytime. 展开更多
关键词 closed greenhouse COOLING TEMPERATURE EFFICIENCY
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On closed weak supplemented modules
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作者 曾庆怡 史美华 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2006年第2期210-215,共6页
A module M is called closed weak supplemented if for any closed submodule N of M, there is a submodule K of M such that M=K+N and K∩N<<M. Any direct summand of closed weak supplemented module is also closed wea... A module M is called closed weak supplemented if for any closed submodule N of M, there is a submodule K of M such that M=K+N and K∩N<<M. Any direct summand of closed weak supplemented module is also closed weak supplemented. Any nonsingular image of closed weak supplemented module is closed weak supplemented. Nonsingular V-rings in which all nonsingular modules are closed weak supplemented are characterized in Section 4. 展开更多
关键词 closed submodules closed weak supplemented Small submodule
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The Predetermined Failure of Murphy's Quest for Freedom in Closed Systems--Narritivity Temporality in Murphy
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作者 杨静 《海外英语》 2018年第6期179-181,共3页
This essay aims at an analysis of Murphy's failure of his quest for freedom from the aspect of narrative temporality whichwill focus on order, duration and frequency. From the perspective of temporal order, the es... This essay aims at an analysis of Murphy's failure of his quest for freedom from the aspect of narrative temporality whichwill focus on order, duration and frequency. From the perspective of temporal order, the essay will endeavor to probe into the pro-lepsis in the novel to analyse predetermined narrative and its function. Considering with temporal duration, this essay will penetratethe deceleration of narrative—scene and pause in Murphy to explore its thematic meaning. To investigate the temporal frequency,iterative narrative within text will be exemplified to discuss closed systems in the novel. Based on the analysis of the narrativity tem-porality in Murphy, the essay will focuses on that how its narrative strategy well embodies its theme—the predetermined failure ofMurphy's quest for freedom in closed systems. 展开更多
关键词 narrative temporality closed system predetermined FREEDOM
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Multiresolution for Closed Curves and Surfaces Using Wavelets
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作者 ZHAO Gang BAI Jie WANG Chao YAO Fu-sheng 《Computer Aided Drafting,Design and Manufacturing》 2005年第2期1-13,共13页
Multiresolution modeling is becoming a powerful tool for fast display, and geometric data compression and transmission of complex shapes. Most of the existing literatures investigating the multiresolution for B-spline... Multiresolution modeling is becoming a powerful tool for fast display, and geometric data compression and transmission of complex shapes. Most of the existing literatures investigating the multiresolution for B-spline curves and surfaces are concentrated on open ones. In this paper, we focus on the multiresolution representations and editing of closed B-spline curves and surfaces using wavelets. A repetition approach is adopted for the multiresolution analysis of closed B-spline curves and surfaces. Since the closed curve or surface itself is periodic, it can overcome the drawback brought by the repetition method, i.e. introducing the discontinuities at the boundaries. Based on the models at different multiresolution levels, the multiresolution editing methods of closed curves and surfaces are introduced. Users can edit the overall shape of a closed one while preserving its details, or change its details without affecting its overall shape. 展开更多
关键词 closed B-spline curves closed B-spline surfaces WAVELETS multiresolution representation analysis multiresolution representation multiresolution editing
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Recent advances in the study of hepatitis B virus covalently closed circular DNA 被引量:10
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作者 Mengying Ji Kanghong Hu 《Virologica Sinica》 SCIE CAS CSCD 2017年第6期454-464,共11页
Chronic hepatitis B infection is caused by hepatitis B virus(HBV) and a total cure is yet to be achieved. The viral covalently closed circular DNA(ccc DNA) is the key to establish a persistent infection within hepatoc... Chronic hepatitis B infection is caused by hepatitis B virus(HBV) and a total cure is yet to be achieved. The viral covalently closed circular DNA(ccc DNA) is the key to establish a persistent infection within hepatocytes. Current antiviral strategies have no effect on the pre-existing ccc DNA reservoir. Therefore, the study of the molecular mechanism of ccc DNA formation is becoming a major focus of HBV research. This review summarizes the current advances in ccc DNA molecular biology and the latest studies on the elimination or inactivation of ccc DNA, including three major areas:(1) epigenetic regulation of ccc DNA by HBV X protein,(2) immune-mediated degradation,and(3) genome-editing nucleases. All these aspects provide clues on how to finally attain a cure for chronic hepatitis B infection. 展开更多
关键词 hepatitis B virus(HBV) covalently closed circular DNA(cccDNA) HBX immunemediated genome-editing nucleases
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Novel therapeutic approaches for hepatitis B virus covalently closed circular DNA 被引量:5
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作者 Motoko Ohno Motoyuki Otsuka +3 位作者 Takahiro Kishikawa Takeshi Yoshikawa Akemi Takata Kazuhiko Koike 《World Journal of Gastroenterology》 SCIE CAS 2015年第23期7084-7088,共5页
Hepatitis B virus(HBV) infection is a major global health problem. Although current therapies, such as the use of nucleos(t)ide analogs, inhibit HBV replication efficiently, they do not eliminate covalently closed cir... Hepatitis B virus(HBV) infection is a major global health problem. Although current therapies, such as the use of nucleos(t)ide analogs, inhibit HBV replication efficiently, they do not eliminate covalently closed circular DNA(ccc DNA), which persists in hepatocyte nuclei. As HBV ccc DNA is a viral transcription template, novel therapeutic approaches to directly target HBV ccc DNA are necessary to completely eradicate persistent HBV infections. HBV ccc DNA levels in HBV-infected human liver cells are extremely low; thus, more reliable and simple measurement methods are needed to correctly monitor their levels during therapeutic treatment. Although reverse transcription-polymerase chain reaction or Southern blot procedures are currently used in research studies, these methods are not completely reliable and are also time-consuming and labor-intensive. Genome editing technologies, such as zinc finger nucleases, transcription activator-like effector nucleases, and the clustered regularly interspaced short palindromic repeats/Cas9(CRISPR/Cas9) system, which are designed to target specific DNA sequences, represent highly promising potential therapeutic tools. In particular, the CRISPR/Cas9 system is an easily customizable sequencespecific nuclease with high flexibility and may be the most feasible approach to target HBV ccc DNA. Further research to develop easier, safer, and more effective protocols should be pursued. 展开更多
关键词 HEPATITIS B VIRUS Covalently closed circularHBV DNA GENOME EDITING
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Closed form solutions for free vibrations of rectangular Mindlin plates 被引量:7
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作者 Yufeng Xing Bo Liu The Solid Mechanics Research Center, Beihang University,100191 Beijing, China 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2009年第5期689-698,共10页
A new two-eigenfunctions theory, using the amplitude deflection and the generalized curvature as two fundamental eigenfunctions, is proposed for the free vibration solutions of a rectangular Mindlin plate. The three c... A new two-eigenfunctions theory, using the amplitude deflection and the generalized curvature as two fundamental eigenfunctions, is proposed for the free vibration solutions of a rectangular Mindlin plate. The three classical eigenvalue differential equations of a Mindlin plate are reformulated to arrive at two new eigenvalue differential equations for the proposed theory. The closed form eigensolutions, which are solved from the two differential equations by means of the method of separation of variables are identical with those via Kirchhoff plate theory for thin plate, and can be employed to predict frequencies for any combinations of simply supported and clamped edge conditions. The free edges can also be dealt with if the other pair of opposite edges are simply supported. Some of the solutions were not available before. The frequency parameters agree closely with the available ones through pb-2 Rayleigh-Ritz method for different aspect ratios and relative thickness of plate. 展开更多
关键词 Mindlin plate Free vibration closed form solution Separation of variable
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