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Determination of Complexity Factor and Its Relationship with Accuracy of Representation for DEM Terrain 被引量:8
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作者 LIU Chun SUN Weiwei WU Hangbin 《Geo-Spatial Information Science》 2010年第4期249-256,共8页
Based on the estimating rule of the normal vector angles between two adjacent terrain units, we use the concept of terrain complexity factor to quantify the terrain complexity of DEM, and then the formula of terrain c... Based on the estimating rule of the normal vector angles between two adjacent terrain units, we use the concept of terrain complexity factor to quantify the terrain complexity of DEM, and then the formula of terrain complexity factor in Raster DEM and TIN DEM is deduced theoretically. In order to make clear how the terrain complexity factor ECF and the average elevation h affect the accuracy of DEM terrain representation RMSEEt, the formula of Gauss synthetical surface is applied to simulate several real terrain surfaces, each of which has different terrain complexity. Through the statistical analysis of linear regression in simula- tion data, the linear equation between accuracy of DEM terrain representation RMSEEt, terrain complexity factor ECF and the average elevation h is achieved. A new method is provided to estimate the accuracy of DEM terrain representation RMSEEt with a certain terrain complexity and it gives convincing theoretical evidence for DEM production and the corresponding error research in the future. 展开更多
关键词 terrain complexity factor Gauss synthetical surface ACCURACY DEM terrain representation
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Structural Complexity Analysis of Information Systems Based on Petri Nets 被引量:3
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作者 王景光 甘仞初 《Journal of Beijing Institute of Technology》 EI CAS 1999年第4期416-423,共8页
Aim To present a quantitative method for structural complexity analysis and evaluation of information systems. Methods Based on Petri net modeling and analysis techniques and with the aid of mathematical tools in ge... Aim To present a quantitative method for structural complexity analysis and evaluation of information systems. Methods Based on Petri net modeling and analysis techniques and with the aid of mathematical tools in general net theory(GNT), a quantitative method for structure description and analysis of information systems was introduced. Results The structural complexity index and two related factors, i.e. element complexity factor and connection complexity factor were defined, and the relations between them and the parameters of the Petri net based model of the system were derived. Application example was presented. Conclusion The proposed method provides a theoretical basis for quantitative analysis and evaluation of the structural complexity and can be applied in the general planning and design processes of the information systems. 展开更多
关键词 information system Petri Nets structural complexity element complexity factor connection complexity factor
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Role of brahma-related gene 1/brahma-associated factor subunits in neural stem/progenitor cells and related neural developmental disorders
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作者 Nai-Yu Ke Tian-Yi Zhao +2 位作者 Wan-Rong Wang Yu-Tong Qian Chao Liu 《World Journal of Stem Cells》 SCIE 2023年第4期235-247,共13页
Different fates of neural stem/progenitor cells(NSPCs)and their progeny are determined by the gene regulatory network,where a chromatin-remodeling complex affects synergy with other regulators.Here,we review recent re... Different fates of neural stem/progenitor cells(NSPCs)and their progeny are determined by the gene regulatory network,where a chromatin-remodeling complex affects synergy with other regulators.Here,we review recent research progress indicating that the BRG1/BRM-associated factor(BAF)complex plays an important role in NSPCs during neural development and neural developmental disorders.Several studies based on animal models have shown that mutations in the BAF complex may cause abnormal neural differentiation,which can also lead to various diseases in humans.We discussed BAF complex subunits and their main characteristics in NSPCs.With advances in studies of human pluripotent stem cells and the feasibility of driving their differentiation into NSPCs,we can now investigate the role of the BAF complex in regulating the balance between self-renewal and differentiation of NSPCs.Considering recent progress in these research areas,we suggest that three approaches should be used in investigations in the near future.Sequencing of whole human exome and genome-wide association studies suggest that mutations in the subunits of the BAF complex are related to neurodevelopmental disorders.More insight into the mechanism of BAF complex regulation in NSPCs during neural cell fate decisions and neurodevelopment may help in exploiting new methods for clinical applications. 展开更多
关键词 Neural stem/progenitor cell BRG1/BRM-associated factor complex SUBUNIT Proliferation DIFFERENTIATION Neural developmental disorde
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Mammalian target of rapamycin complex 1 as an inducer of neurotrophic factors in dopaminergic neurons 被引量:1
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作者 Sang Ryong Kim 《Neural Regeneration Research》 SCIE CAS CSCD 2014年第23期2036-2037,共2页
The defining neuropathological feature of Parkinson's disease (PD) is the loss of nigrostriatal dopaminergic (DA) projections. This results in striatal dopamine levels and a biochemical reduction of movement diso... The defining neuropathological feature of Parkinson's disease (PD) is the loss of nigrostriatal dopaminergic (DA) projections. This results in striatal dopamine levels and a biochemical reduction of movement disorders, such as a tremor at rest, rigidity of the limbs, bradykinesia, and postural instability (Kim et al., 2011; Kim et al., 2012; Burke and O'Malley, 2013; Leem et al., 2014; Namet al., 2014). 展开更多
关键词 RHEB Mammalian target of rapamycin complex 1 as an inducer of neurotrophic factors in dopaminergic neurons GDNF BDNF
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Modified projective synchronization with complex scaling factors of uncertain real chaos and complex chaos
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作者 张芳芳 刘树堂 余卫勇 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第12期141-151,共11页
To increase the variety and security of communication, we present the definitions of modified projective synchronization with complex scaling factors (CMPS) of real chaotic systems and complex chaotic systems, where... To increase the variety and security of communication, we present the definitions of modified projective synchronization with complex scaling factors (CMPS) of real chaotic systems and complex chaotic systems, where complex scaling factors establish a link between real chaos and complex chaos. Considering all situations of unknown parameters and pseudo-gradient condition, we design adaptive CMPS schemes based on the speed-gradient method for the real drive chaotic system and complex response chaotic system and for the complex drive chaotic system and the real response chaotic system, respectively. The convergence factors and dynamical control strength are added to regulate the convergence speed and increase robustness. Numerical simulations verify the feasibility and effectiveness of the presented schemes. 展开更多
关键词 modified projective synchronization complex scaling factors complex chaotic systems speed-gradient method
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Functions of nuclear factor Y in nervous system development,function and health
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作者 Pedro Moreira Roger Pocock 《Neural Regeneration Research》 SCIE CAS 2025年第10期2887-2894,共8页
Nuclear factor Y is a ubiquitous heterotrimeric transcription factor complex conserved across eukaryotes that binds to CCAAT boxes,one of the most common motifs found in gene promoters and enhancers.Over the last 30 y... Nuclear factor Y is a ubiquitous heterotrimeric transcription factor complex conserved across eukaryotes that binds to CCAAT boxes,one of the most common motifs found in gene promoters and enhancers.Over the last 30 years,research has revealed that the nuclear factor Y complex controls many aspects of brain development,including differentiation,axon guidance,homeostasis,disease,and most recently regeneration.However,a complete understanding of transcriptional regulatory networks,including how the nuclear factor Y complex binds to specific CCAAT boxes to perform its function remains elusive.In this review,we explore the nuclear factor Y complex’s role and mode of action during brain development,as well as how genomic technologies may expand understanding of this key regulator of gene expression. 展开更多
关键词 axon guidance CCAAT boxes neuronal degeneration neuronal differentiation neuronal regeneration nuclear factor Y complex transcription factor transcriptional regulation
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Characterization of Energy_Transduction in Thermal Pretreated Chloroplast from Spinach
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作者 彭建新 万常照 +4 位作者 邹永龙 陈根云 钱月琴 袁勤 王国强 《Acta Botanica Sinica》 CSCD 2001年第1期29-35,共7页
Characterization of energy-transduction on die chloroplast thylakoid membranes from spinach (Spinacia oleracca L.) after thermal pretreatment was investigated. The related reactions of energy-transduction in chloropla... Characterization of energy-transduction on die chloroplast thylakoid membranes from spinach (Spinacia oleracca L.) after thermal pretreatment was investigated. The related reactions of energy-transduction in chloroplasts were seriously affected by thermal pretreatment. The results were obtained as following: (1) The rate of cyclic photophosphorylation declined when the pretreatment temperature increased in the range of 25 to 45 degreesC. (2) The thermal pretreatment led to a decrease of the activity of thylakoid membrane-bounded ATPase. (3) Proton uptake of chloroplasts acid the fluorescence quenching of 9-aminoacridine (9-AA) in thylakoid membrane decreased after the thermal pretreatment, but addition of dicyclohexylcarbodiimide (DCCD) could partially restore the fluorescence quenching of 9-AA. (4) Both the rates of fast phase in electrochroism absorption change at 515 nm and the millisecond delayed light emission (ms-DLE) of chloroplast showed a progressive decrease upon raising the temperature of pretreatment. (5) Immunbloting analysis showed that the thermal pretreatment caused the changes of protein content and the electrophoresis mobility of thylakoid membrane-bound ATPase and its alpha -subunit. (6) If the temperature of pretreatment were higher than 33 degreesC, oxygen uptake of PS I -mediated in the samples was rapidly inhibited, but addition of sinapine into the reaction medium could partially restore the ability of oxygen uptake in the samples. These results are briefly discussed in relation to the change of permeability of thylakoid membranes, the dissociation of coupling factor complex as well as accumulation of the radicals in the thylakoid membranes after thermal pretreatment. 展开更多
关键词 Spinacia oleracea CHLOROPLAST thermal pretreatment energy-transduction permeability of thylakoid membranes coupling factor complex
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Anti-plane analysis of semi-infinite crack in piezoelectric strip 被引量:5
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作者 郭俊宏 刘萍 +1 位作者 卢子兴 秦太验 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2011年第1期75-82,共8页
Using the complex variable function method and the technique of the conformal mapping, the fracture problem of a semi-infinite crack in a piezoelectric strip is studied under the anti-plane shear stress and the in-pla... Using the complex variable function method and the technique of the conformal mapping, the fracture problem of a semi-infinite crack in a piezoelectric strip is studied under the anti-plane shear stress and the in-plane electric load. The analytic solutions of the field intensity factors and the mechanical strain energy release rate are presented under the assumption that the surface of the crack is electrically impermeable. When the height of the strip tends to infinity, the analytic solutions of an infinitely large piezoelectric solid with a semi-infinite crack are obtained. Moreover, the present results can be reduced to the well-known solutions for a purely elastic material in the absence of the electric loading. In addition, numerical examples are given to show the influences of the loaded crack length, the height of the strip, and the applied mechanical/electric loads on the mechanical strain energy release rate. 展开更多
关键词 piezoelectric strip semi-infinite crack complex variable function method field intensity factor mechanical strain energy release rate
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Efficacy of EGFR Tyrosine Kinase Inhibitors in Non-small Cell Lung Cancer Patients Harboring Different Types of EGFR Mutations:A Retrospective Analysis 被引量:8
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作者 刘华丽 韩光 +5 位作者 彭敏 翁一鸣 袁静萍 杨桂芳 于金明 宋启斌 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 2017年第6期864-872,共9页
With the development of molecular pathology, many types of epidermal growth factor receptor(EGFR) mutations have been identified. The efficacy of EGFR tyrosine kinase inhibitors(EGFR-TKIs) in non-small cell lung c... With the development of molecular pathology, many types of epidermal growth factor receptor(EGFR) mutations have been identified. The efficacy of EGFR tyrosine kinase inhibitors(EGFR-TKIs) in non-small cell lung cancer(NSCLC) patients with different types of EGFR mutations, especially in patients with single rare mutations or complex mutations(co-occurrence of two or more different mutations), has not been fully understood. This study aimed to examine the efficacy of EGFR-TKIs in NSCLC patients with different types of EGFR mutations. Clinical data of 809 NSCLC patients who harbored different types of EGFR mutations and treated from January 2012 to October 2016 at Renmin Hospital and Zhongnan Hospital, Wuhan, were retrospectively reviewed. The clinical characteristics of these patients and the efficacy of EGFR-TKIs were analyzed. Among these patients, 377 patients had only the EGFR del-19 mutation, 362 patients the EGFR L858R mutation in exon 21, 33 patients single rare mutations and 37 patients complex mutations. Among these 809 patients, 239 patients were treated with EGFR-TKIs. In all the 239 patients, the disease control rate(DCR) was 93.7% with two patients(0.2%) achieving complete response(CR), the median progression free survival(PFS) was 13.0 months(95% confidence interval [CI], 11.6–14.4 months), and the median overall survival(OS) was 55.0 months(95% CI, 26.3–83.7 months). Subgroup analysis revealed that the DCR in patients harboring single rare or complex mutations of EGFR was significantly lower than in those with del-19 or L858 R mutation(P〈0.001). Patients with classic mutations(del-19 and/or L858 R mutations) demonstrated longer PFS(P〈0.001) and OS(P=0.017) than those with uncommon mutations(single rare and/or complex mutations). Furthermore, the patients with single rare mutations had shorter median OS than in those with other mutations. Multivariate Cox regression analysis identified that the type of EGFR mutations was an independent risk factor for PFS(hazard ratio [HR]=0.308, 95% CI, 0.191–0.494, P〈0.001) and OS(HR=0.221, 95% CI, 0.101–0.480, P〈0.001). The results suggest that the single rare or complex EGFR mutations confer inferior efficacy of EGFR-TKIs treatment to the classic mutations. The prognosis of the single rare EGFR mutations is depressing. EGFR-TKIs may be not a good choice for NSCLC patients with single rare mutations of EGFR. Further studies in these patients with uncommon mutations(especially for the patients with single rare mutations) are needed to determine a better precision treatment. 展开更多
关键词 non-small cell lung cancer epidermal growth factor receptor rare mutations complex mutations tyrosine kinase inhibitors
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ANALYSIS OF COMPLEX STRESS INTENSITIES FOR CRACKED LAMINATES
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作者 胡互让 吴承平 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1996年第2期119-132,共14页
Classical plate theory has been used to find out interfacial stress intensity factors in composite laminates. By using a well-known relation between the crack-tip energy release rate and the complex stress intensity f... Classical plate theory has been used to find out interfacial stress intensity factors in composite laminates. By using a well-known relation between the crack-tip energy release rate and the complex stress intensity factor. a closed-form solution for complex. Stress intensity in terms of external loading and a mode mix parameter for fairly. general composite laminates is given. Then a procedure for determining this mode mix. parameter is presented. followed by numerical results for some laminates. Small scale contact condition is expressed in terms of external loading In particular, a symmetric property of interfacial toughness curye is proven. Finally. the accuracy of failure load predicled by elininating oscllation index is discussed. and an example is presented to show the validity and limitation of β=0 approximation. 展开更多
关键词 composite materials. laminates complex stress intensity factor.energy release rate. inlerface Crack
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