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Comprehensive analysis of gene mutations and mismatch repair in Chinese colorectal cancer patients
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作者 Huang Chen Rui-Ying Jiang +11 位作者 Zhan Hua Xiao-Wei Wang Xiao-Li Shi Ye Wang Qian-Qian Feng Jie Luo Wu Ning Yan-Fen Shi Da-Kui Zhang Bei Wang Jian-Zheng Jie Ding-Rong Zhong 《World Journal of Gastrointestinal Oncology》 SCIE 2024年第6期2673-2682,共10页
BACKGROUND RAS,BRAF,and mismatch repair(MMR)/microsatellite instability(MSI)are crucial biomarkers recommended by clinical practice guidelines for colorectal cancer(CRC).However,their characteristics and influencing f... BACKGROUND RAS,BRAF,and mismatch repair(MMR)/microsatellite instability(MSI)are crucial biomarkers recommended by clinical practice guidelines for colorectal cancer(CRC).However,their characteristics and influencing factors in Chinese patients have not been thoroughly described.AIM To analyze the clinicopathological features of KRAS,NRAS,BRAF,and PIK3CA mutations and the DNA MMR status in CRC.METHODS We enrolled 2271 Chinese CRC patients at the China-Japan Friendship Hospital.MMR proteins were tested using immunohistochemical analysis,and the KRAS/NRAS/BRAF/PIK3CA mutations were determined using quantitative polymerase chain reaction.Microsatellite status was determined using an MSI detection kit.Statistical analyses were conducted using SPSS software and logistic regression.RESULTS The KRAS,NRAS,BRAF,and PIK3CA mutations were detected in 44.6%,3.4%,3.7%,and 3.9% of CRC patients,respectively.KRAS mutations were more likely to occur in patients with moderate-to-high differentiation.BRAF mutations were more likely to occur in patients with right-sided CRC,poorly differentiated,or no perineural invasion.Deficient MMR(dMMR)was detected in 7.9% of all patients and 16.8% of those with mucinous adenocarcinomas.KRAS,NRAS,BRAF,and PIK3CA mutations were detected in 29.6%,1.1%,8.1%,and 22.3% of patients with dMMR,respectively.The dMMR was more likely to occur in patients with a family history of CRC,aged<50 years,right-sided CRC,poorly differentiated histology,no perineural invasion,and with carcinoma in situ,stage I,or stage II tumors.CONCLUSION This study analyzed the molecular profiles of KRAS,NRAS,BRAF,PIK3CA,and MMR/MSI in CRC,identifying key influencing factors,with implications for clinical management of CRC. 展开更多
关键词 Colorectal cancer Deficient mismatch repair Microsatellite instability Gene mutation comprehensive analysis
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Comprehensive Analysis Method of Slope Stability Based on the Limit Equilibrium and Finite Element Methods and Its Application
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作者 Yajun Wang Yifeng Li Jinzhou Chen 《Open Journal of Civil Engineering》 2023年第4期555-571,共17页
To study the safety and stability of large slopes, taking the right side slope of the Yuxi’an tunnel of the Yuchu Expressway Bridge in Yunnan Province as an example, limit equilibrium and finite element analysis were... To study the safety and stability of large slopes, taking the right side slope of the Yuxi’an tunnel of the Yuchu Expressway Bridge in Yunnan Province as an example, limit equilibrium and finite element analysis were applied to engineering examples to calculate the stability coefficient of the slope before and after excavation in the natural state. After comparative analysis, it was concluded that the former had a clear mechanical model and concept, which could quickly provide stability results;the latter could accurately determine the sliding surface of the slope and simulate the stress state changes of the rock and soil mass. The stability coefficients calculated by the two methods were within the stable range, but their values were different. On this basis, combined with the calculation principles, advantages and disadvantages of the two methods, a comprehensive analysis method of slope stability based on the limit equilibrium and finite element methods was proposed, and the rationality of the stability coefficient calculated by this method was judged for a slope case. 展开更多
关键词 Slope Body Excavation Mechanical Model Sliding Surface Coefficient of Stability Calculation Principle comprehensive analysis Method
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PRIMARY PLASMA CELL LEUKEMIA(A COMPREHENSIVE ANALYSIS OF 44 CASES)
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作者 蔡则骥 张国祯 《Chinese Journal of Cancer Research》 SCIE CAS CSCD 1991年第2期74-77,共4页
Four cases of primary plasma cell leukemia (PPCL) admitted to Zhongshan Hospital from 1959 to 1987 are reported with a review on additional 40 cases reported in China. Comparing with the 57 cases of multiple myeloma (... Four cases of primary plasma cell leukemia (PPCL) admitted to Zhongshan Hospital from 1959 to 1987 are reported with a review on additional 40 cases reported in China. Comparing with the 57 cases of multiple myeloma (MM) treated in our hospital, the following features were observed in PPCL: (1) The age was younger, with a mean of 45.2 years, 34.1% of the patients were under 40 years. (2) Onset was abrupt. Duration from onset to diagnosis was 2 months or less in 77% patients but never beyond 6 months. (3) 81.8% patients had liver enlargement, 59.1% splenomegaly and 61.4% sternum tenderness. (4) All patients showed marked anemia with an average hemoglobin of 65 g/L. BPC count was less than 100 × 109/L in 76% patients and WBC was more than 10×109/L in 77%. (5) Plasma cell number in the marrow was markedly increased with an average of 69%, of which the blast cells and immature forms were predominant. (6) No destruction of bones was shown on X-ray film in 68.3% patients. (7) The response to chemotherapy was poor with a total response rate of 18% and a mean survival of 2 months. All the above-mentioned clinical features were significantly different from those of MM. In addition, these two diseases were also different in cytology, cytogenetics and ultrastructure. Therefore, PPCL should be considered as a special type of acute leukemia distinct from MM. High dose of alkylating agents in combination with autologous bone marrow transplantation might improve the prognoses. 展开更多
关键词 PPCL PRIMARY PLASMA CELL LEUKEMIA A comprehensive analysis OF 44 CASES
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Utilizing comprehensive decision analysis methods to determine an optimal planting pattern and nitrogen application for winter oilseed rape 被引量:2
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作者 DU Ya-dan CUI Bing-jing +3 位作者 ZHANG Qian SUN Jun WANG Zhen NIU Wen-quan 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2020年第9期2229-2238,共10页
Oilseed rape is one of the most important oil crops globally.Attaining the appropriate cultivation method(planting pattern and nitrogen level)is necessary to achieve high yield,quality and resource utilization efficie... Oilseed rape is one of the most important oil crops globally.Attaining the appropriate cultivation method(planting pattern and nitrogen level)is necessary to achieve high yield,quality and resource utilization efficiency.However,the optimal method for oilseed rape varies across countries and regions.The objective of the present study was to determine an appropriate cultivation method,including planting pattern and nitrogen application,for winter oilseed rape in northwestern China.Two planting patterns:ridge film mulching and furrow planting(RFMF)and flat planting(FP),and six nitrogen(N)amounts:0(N0),60(N60),120(N120),180(N180),240(N240),and 300(N300)kg N ha–1 were applied across three growing seasons(2014–2017).Three comprehensive decision analysis methods:principal component analysis,grey correlation degree analysis and the combined entropy weight and dynamic technique for order preference by similarity to ideal solution method were used to evaluate the growth and physiological indicators,nutrient uptake,yield,quality,evapotranspiration,and water use efficiency of winter oilseed rape.Planting pattern,nitrogen amount and their interaction significantly affected the indicators aforementioned.The RFMF pattern significantly increased all indicators over the FP pattern.Application of N also markedly increased all the indicators except for seed oil content,but the yield,oil production and water use efficiency were decreased when N fertilizer exceeded 180 kg N ha–1 under FP and 240 kg N ha–1 under RFFM.The evaluation results of the three comprehensive decision analysis methods indicated that RFMF planting pattern with 240 kg N ha–1 is an appropriate cultivation method for winter oilseed rape in northwestern China.These findings are of vital significance to maximize yield,optimize quality and improve resource use efficiencies of winter oilseed rape. 展开更多
关键词 appropriate cultivation method comprehensive decision analysis method northwestern China winter oilseed rape
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Comprehensive Reliability Allocation Method for CNC Lathes Based on Cubic Transformed Functions of Failure Mode and Effects Analysis 被引量:8
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作者 YANG Zhou ZHU Yunpeng +1 位作者 REN Hongrui ZHANG Yimin 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2015年第2期315-324,共10页
Reliability allocation of computerized numerical controlled(CNC)lathes is very important in industry.Traditional allocation methods only focus on high-failure rate components rather than moderate failure rate compon... Reliability allocation of computerized numerical controlled(CNC)lathes is very important in industry.Traditional allocation methods only focus on high-failure rate components rather than moderate failure rate components,which is not applicable in some conditions.Aiming at solving the problem of CNC lathes reliability allocating,a comprehensive reliability allocation method based on cubic transformed functions of failure modes and effects analysis(FMEA)is presented.Firstly,conventional reliability allocation methods are introduced.Then the limitations of direct combination of comprehensive allocation method with the exponential transformed FMEA method are investigated.Subsequently,a cubic transformed function is established in order to overcome these limitations.Properties of the new transformed functions are discussed by considering the failure severity and the failure occurrence.Designers can choose appropriate transform amplitudes according to their requirements.Finally,a CNC lathe and a spindle system are used as an example to verify the new allocation method.Seven criteria are considered to compare the results of the new method with traditional methods.The allocation results indicate that the new method is more flexible than traditional methods.By employing the new cubic transformed function,the method covers a wider range of problems in CNC reliability allocation without losing the advantages of traditional methods. 展开更多
关键词 CNC lathes reliability failure modes and effects analysis(FMEA) cubic transformed function comprehensive allocation
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Non-isothermal Kinetic Analysis on the Thermal Decomposition of the Phase 517 from Hydration Product of Magnesium Sulfide Cement 被引量:2
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作者 CUI Baodong GUAN Yan BI Wanli 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2023年第2期374-380,共7页
In order to better understand the thermodynamic properties of magnesium oxysulfate(MOS)cement,pure reagent was analyzed to prepare magnesium sulfide cement,non-isothermal kinetics calculation of the main hydration pro... In order to better understand the thermodynamic properties of magnesium oxysulfate(MOS)cement,pure reagent was analyzed to prepare magnesium sulfide cement,non-isothermal kinetics calculation of the main hydration products was also carried out,and the conversion process of magnesium sulfide cement 517 phase at different temperatures was investigated.Composition of magnesium sulfide cement prepared was measured by XRD technique,and decomposed by a comprehensive thermal analyzer,and DSC curves of magnesium sulfide cement under different temperature rising rates were processed by Kinssinger method and Dolye-Ozawa method.According to the TG-DSC curves of magnesium sulfide cement,the thermal decomposition reaction process can be divided into five stages under normal conditions.The DSC curve was processed by Kinssinger method and Dolye-Ozawa method,and the kinetic analysis was carried out to calculate the 517 phase activation energy of magnesium sulfide cement.The three stages correspond to different activation energies.Therefore,flame retardant mechanism and thermal decomposition mechanism of magnesium sulfide cement based materials are deduced. 展开更多
关键词 magnesium sulfide cement comprehensive thermal analysis nonisothermal dynamics 517 phase
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The First-Order Comprehensive Sensitivity Analysis Methodology (1<sup>st</sup>-CASAM) for Scalar-Valued Responses: II. Illustrative Application to a Heat Transport Benchmark Model
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作者 Dan Gabriel Cacuci 《American Journal of Computational Mathematics》 2020年第2期290-310,共21页
This work illustrates the application of the 1<sup>st</sup>-CASAM to a paradigm heat transport model which admits exact closed-form solutions. The closed-form expressions obtained in this work for the sens... This work illustrates the application of the 1<sup>st</sup>-CASAM to a paradigm heat transport model which admits exact closed-form solutions. The closed-form expressions obtained in this work for the sensitivities of the temperature distributions within the model to the model’s parameters, internal interfaces and external boundaries can be used to benchmark commercial and production software packages for simulating heat transport. The 1<sup>st</sup>-CASAM highlights the novel finding that response sensitivities to the imprecisely known domain boundaries and interfaces can arise both from the definition of the system’s response as well as from the equations, interfaces and boundary conditions that characterize the model and its imprecisely known domain. By enabling, in premiere, the exact computations of sensitivities to interface and boundary parameters and conditions, the 1<sup>st</sup>-CASAM enables the quantification of the effects of manufacturing tolerances on the responses of physical and engineering systems. 展开更多
关键词 First-Order comprehensive Adjoint Sensitivity analysis Methodology (1st-CASAM) Response Sensitivities for Coupled Systems Involving Imprecisely Known Interfaces Parameters And Boundaries Coupled Heat Conduction and Convection
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Analysis of therapeutic effect of comprehensive inter-vention on pain in patients with gastric carcinoma
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作者 林根友 《中国组织工程研究与临床康复》 CAS CSCD 2001年第18期155-,共1页
关键词 analysis of therapeutic effect of comprehensive inter-vention on pain in patients with gastric carcinoma
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Hierarchical Privacy Protection Model in Advanced Metering Infrastructure Based on Cloud and Fog Assistance
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作者 Linghong Kuang Wenlong Shi Jing Zhang 《Computers, Materials & Continua》 SCIE EI 2024年第8期3193-3219,共27页
The Advanced Metering Infrastructure(AMI),as a crucial subsystem in the smart grid,is responsible for measuring user electricity consumption and plays a vital role in communication between providers and consumers.Howe... The Advanced Metering Infrastructure(AMI),as a crucial subsystem in the smart grid,is responsible for measuring user electricity consumption and plays a vital role in communication between providers and consumers.However,with the advancement of information and communication technology,new security and privacy challenges have emerged for AMI.To address these challenges and enhance the security and privacy of user data in the smart grid,a Hierarchical Privacy Protection Model in Advanced Metering Infrastructure based on Cloud and Fog Assistance(HPPM-AMICFA)is proposed in this paper.The proposed model integrates cloud and fog computing with hierarchical threshold encryption,offering a flexible and efficient privacy protection solution that significantly enhances data security in the smart grid.The methodology involves setting user protection levels by processing missing data and utilizing fuzzy comprehensive analysis to evaluate user importance,thereby assigning appropriate protection levels.Furthermore,a hierarchical threshold encryption algorithm is developed to provide differentiated protection strategies for fog nodes based on user IDs,ensuring secure aggregation and encryption of user data.Experimental results demonstrate that HPPM-AMICFA effectively resists various attack strategies while minimizing time costs,thereby safeguarding user data in the smart grid. 展开更多
关键词 AMI cloud and fog assistance fuzzy comprehensive analysis hierarchical threshold encryption
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Planetary health risks in urban agriculture
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作者 Nilanjana Ganguli Anna Maria Subic +1 位作者 Janani Maheswaran Byomkesh Talukder 《Global Health Journal》 2024年第1期4-10,共7页
Urban agriculture is gaining recognition for its potential contributions to environmental resilience and climate change adaptation,providing advantages such as urban greening,reduced heat island effects,and decreased ... Urban agriculture is gaining recognition for its potential contributions to environmental resilience and climate change adaptation,providing advantages such as urban greening,reduced heat island effects,and decreased air pollution.Moreover,it indirectly supports communities during weather events and natural disasters,ensuring food security and fostering community cohesion.However,concerns about planetary health risks persist in highly urbanized and climate-affected areas.Employing electronic databases such as Web of Science and PubMed and adhering to Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines,we identified 55 relevant papers to comprehend the planetary health risks associated with urban agriculture,The literature review identified five distinct health risks related to urban agriculture:(1)trace metal risks in urban farms;(2)health risks associated with wastewater irrigation;(3)zoonotic risks;(4)other health risks;and(5)social and economic risks.The study highlights that urban agriculture,while emphasizing environmental benefits,particularly raises concerns about trace metal bioaccumulation in soil and vegetables,posing health risks for populations.Other well studied risks included wastewater irrigation and backyard livestock farming.The main limitations in the available literature were in studying infectious diseases and antibiotic resistance associated with urban agriculture. 展开更多
关键词 Urban agriculture URBANIZATION Systems-thinking Planetary health impacts comprehensive risk analysis Planetary Health Risks analysis of Urban Agriculture Framework(PHRAUAF) HEURISTIC
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Experiencing a traumatic spinal cord injury—Analysis on the view of the theory of Watson’s transpersonal caring 被引量:1
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作者 Zuila Maria de Figueiredo Carvalho Juan Jose Tirado Darder +2 位作者 Priscila Alencar Mendes Reis Samira Rocha Magalhaes Samia Jardelle Costa de Freitas Maniva 《Journal of Biomedical Science and Engineering》 2013年第7期14-20,共7页
This is an inquiry that seeks to understand the meaning of experiencing a spinal cord injury for hospitalized Brazilian and Portuguese patients. A quailtative study was achieved in two care services to spinal cord inj... This is an inquiry that seeks to understand the meaning of experiencing a spinal cord injury for hospitalized Brazilian and Portuguese patients. A quailtative study was achieved in two care services to spinal cord injury in Fortaleza-Brazil and Lisboa-Portugal. The subjects were 30 patients with complete spinal cord injury. The findings were obtained through a semi-structured interview, which took place at different times and it was used the following guiding question: What does it mean for you to experience a spinal cord injury? The data were organized by Bardin technique and analysis based on the assumptions of the theory of Jean Watson’s care. The speeches of the patients show a diversity of meanings such as: to lose the freedom of going and coming, sexuality and to become dependent on others. It is concluded that this situation of loss overbalances the person’s existence, which is expressed by feelings of sadness, grief, discontent, isolation, anxiety, crying, pain and emotional suffering. These feelings were expressed by the two groups despite being from different cultures. The research enabled the description of multiple dimensions of the meaning of spinal cord injury. It fills the theoretical gap, not yet sufficiently addressed to the practice of caring people with spinal cord injury. 展开更多
关键词 Spinal Cord Injury comprehensive analysis Jean Watson’s Theory
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Harmoniousness analysis of total amount control of water use
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作者 Qian-qi YIN Guo-hua FANG 《Water Science and Engineering》 EI CAS CSCD 2014年第1期49-59,共11页
Based on the fundamental principles of total amount control of water use, the harmony theory was used in this study to develop a concept of the degree of harmony of total amount control of water use. Based on this con... Based on the fundamental principles of total amount control of water use, the harmony theory was used in this study to develop a concept of the degree of harmony of total amount control of water use. Based on this concept, the harmoniousness of total amount control of water use was analyzed in terms of the supply and demand of water resources, water resources management, water use benefits, and water-saving level. An evaluation index system of the degree of harmony of total amount control of water use was established, and a method for calculation of the degree of harmony of total amount control of water use was developed based on the analytic hierarchy process (AHP) and fuzzy comprehensive analysis (FCA) methods. The new evaluation index system was applied to a certain area in Jiangsu Province, China. The degree of harmony of total amount control of water use over this area was calculated for different years. Results indicate that the evaluation index system and calculation method proposed in this study are feasible, and such a harmoniousness analysis can provide scientific references for the strict water resources management system that will be implemented in China in the near future. 展开更多
关键词 total amount control of water usel degree of harmony evaluation index system quantification method analytic hierarchy process method fuzzy comprehensive analysis method
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Reliability Analysis of Unmanned Aerial Vehicles Flight Control System Based on Reliability Analysis Technologies
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作者 蔡爽 姜广君 《Journal of Donghua University(English Edition)》 EI CAS 2018年第3期264-269,共6页
The unmanned aerial vehicles( UAV) has been becoming more and more important in the aviation industry.Despite the superior performance and advanced technology,major accident of UAV happens frequently due to the impact... The unmanned aerial vehicles( UAV) has been becoming more and more important in the aviation industry.Despite the superior performance and advanced technology,major accident of UAV happens frequently due to the impact of their systems,long distance of remote control and skill of manipulator technology.According to the application of engineering application,failure mode effects and criticality analysis( FMECA),failure reporting analysis and corrective action comprehensive analysis systems( FRACAS)and fault tree analysis( FTA)( 3 F) were combined.And also a set of user-friendly,more time,more efficient and accurate reliability analysis system were explored. 展开更多
关键词 failure mode effect and criticality analysis(FMECA) failure reporting analysis and corrective action comprehensive analysis systems(FRACAS) fault tree analysis(FTA) 3F integrated system analysis
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Transcriptome analysis of adherens junction pathway-related genes after peripheral nerve injury 被引量:3
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作者 Sheng Yi Xing-Hui Wang Ling-Yan Xing 《Neural Regeneration Research》 SCIE CAS CSCD 2018年第10期1804-1810,共7页
The neural regeneration process is driven by a wide range of molecules and pathways. Adherens junctions are critical cellular junctions for the integrity of peripheral nerves. However, few studies have systematically ... The neural regeneration process is driven by a wide range of molecules and pathways. Adherens junctions are critical cellular junctions for the integrity of peripheral nerves. However, few studies have systematically characterized the transcript changes in the adherens junction pathway following injury. In this study, a rat model of sciatic nerve crush injury was established by forceps. Deep sequencing data were analyzed using comprehensive transcriptome analysis at 0, 1, 4, 7, and 14 days after injury. Results showed that most individual molecules in the adherens junctions were either upregulated or downregulated after nerve injury. The m RNA expression of ARPC1 B, ARPC3, TUBA8, TUBA1 C, CTNNA2, ACTN3, MET, HGF, NME1 and ARF6, which are involved in the adherens junction pathway and in remodeling of adherens junctions, was analyzed using quantitative real-time polymerase chain reaction. Most of these genes were upregulated in the sciatic nerve stump following peripheral nerve injury, except for CTNNA2, which was downregulated. Our findings reveal the dynamic changes of key molecules in adherens junctions and in remodeling of adherens junctions. These key genes provide a reference for the selection of clinical therapeutic targets for peripheral nerve injury. 展开更多
关键词 peripheral nerve regeneration crushed sciatic nerve RNA-SEQ adherens junctions remodeling of adherens junctions Venn diagram ingenuity pathway analysis differentially expressed genes comprehensive transcript analysis transcriptomics heatmap neural regeneration
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Evaluation and Selection of Sealants and Fillers Using Principal Component Analysis for Cracks in Asphalt Concrete Pavements 被引量:8
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作者 李波 REN Xiaoyu +2 位作者 LI Yanbo MA Weizhong LI Hanlian 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2017年第2期408-412,共5页
The objective of this paper was to develop a comprehensive evaluation method and index to evaluate the performance of sealants and fillers for cracks in asphalt concrete pavements using the method of principal compone... The objective of this paper was to develop a comprehensive evaluation method and index to evaluate the performance of sealants and fillers for cracks in asphalt concrete pavements using the method of principal component analysis. The performance experiments including cone penetration, softening point, flow, resilience and tension at low temperature respectively were conducted by reference of ASTM D5329 for eight sealants and fillers often used in China. There by a principal component model was developed and weight of every index was calculated. The experimental results show that there are significantly different performances for sealants and fillers often used in China. Principal component analysis is an objective method that evaluates and selects the performance of sealants and fillers for cracks in asphalt concrete pavements. 展开更多
关键词 road materials asphalt pavement sealants and fillers principal component analysis comprehensive evaluation
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Property analysis of bistatic forward-looking SAR with arbitrary geometry 被引量:2
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作者 Ziqiang Meng Yachao Li +1 位作者 Mengdao Xing Zheng Bao 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2016年第1期111-127,共17页
Bistatic forward-looking synthetic aperture radar(SAR) has many advantages and applications owing to its twodimensional imaging capability.There could be various imaging configurations because of the geometric flexi... Bistatic forward-looking synthetic aperture radar(SAR) has many advantages and applications owing to its twodimensional imaging capability.There could be various imaging configurations because of the geometric flexibility of bistatic platforms,resulting in kinds of models built independently among which there could be some similar even the same motion features.Comprehensive research on such systems in a more comprehensive and general point of view is required to address their difference and consistency.Property analysis of bistatic forwardlooking SAR with arbitrary geometry is achieved including stripmap and spotlight modes on airborne platform,missile-borne platform,and hybrid platform of both.Emphasis is placed on azimuth space variance of some key parameters significantly affecting the subsequent imaging processing,based on which the frequency spectra are further described and compared considering respective features of different platforms for frequency imaging algorithm developing.Simulation results confirm the effectiveness and correctness of our analysis. 展开更多
关键词 bistatic forward-looking synthetic aperture radar(SAR) comprehensive research property analysis azimuth space variance.
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Illustrative Application of the 2<sup>nd</sup>-Order Adjoint Sensitivity Analysis Methodology to a Paradigm Linear Evolution/Transmission Model: Point-Detector Response 被引量:2
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作者 Dan Gabriel Cacuci 《American Journal of Computational Mathematics》 2020年第3期355-381,共27页
This work illustrates the application of the “Second Order Comprehensive Adjoint Sensitivity Analysis Methodology” (2<sup>nd</sup>-CASAM) to a mathematical model that can simulate the evolution and/or tr... This work illustrates the application of the “Second Order Comprehensive Adjoint Sensitivity Analysis Methodology” (2<sup>nd</sup>-CASAM) to a mathematical model that can simulate the evolution and/or transmission of particles in a heterogeneous medium. The model response is the value of the model’s state function (particle concentration or particle flux) at a point in phase-space, which would simulate a pointwise measurement of the respective state function. This paradigm model admits exact closed-form expressions for all of the 1<sup>st</sup>- and 2<sup>nd</sup>-order response sensitivities to the model’s uncertain parameters and domain boundaries. These closed-form expressions can be used to verify the numerical results of production and/or commercial software, e.g., particle transport codes. Furthermore, this paradigm model comprises many uncertain parameters which have relative sensitivities of identical magnitudes. Therefore, this paradigm model could serve as a stringent benchmark for inter-comparing the performances of all deterministic and statistical sensitivity analysis methods, including the 2<sup>nd</sup>-CASAM. 展开更多
关键词 Second-Order Adjoint comprehensive Sensitivity analysis Methodology (2nd-CASAM) Evolution Benchmark Model Exact and Efficient Computation of First- and Second-Order Response Sensitivities
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Illustrative Application of the 2<sup>nd</sup>-Order Adjoint Sensitivity Analysis Methodology to a Paradigm Linear Evolution/Transmission Model: Reaction-Rate Detector Response 被引量:2
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作者 Dan Gabriel Cacuci 《American Journal of Computational Mathematics》 2020年第3期382-397,共16页
This work continues the illustrative application of the “Second Order Comprehensive Adjoint Sensitivity Analysis Methodology” (2<sup>nd</sup>-CASAM) to a benchmark mathematical model that can simulate th... This work continues the illustrative application of the “Second Order Comprehensive Adjoint Sensitivity Analysis Methodology” (2<sup>nd</sup>-CASAM) to a benchmark mathematical model that can simulate the evolution and/or transmission of particles in a heterogeneous medium. The model response considered in this work is a reaction-rate detector response, which provides the average interactions of particles with the respective detector or, alternatively, the time-average of the concentration of a mixture of substances in a medium. The definition of this model response includes both uncertain boundary points of the benchmark, thereby providing both direct and indirect contributions to the response sensitivities stemming from the boundaries. The exact expressions for the 1<sup>st</sup>- and 2<sup>nd</sup>-order response sensitivities to the boundary and model parameters obtained in this work can serve as stringent benchmarks for inter-comparing the performances of all (deterministic and statistical) sensitivity analysis methods. 展开更多
关键词 Second-Order Adjoint comprehensive Sensitivity analysis Methodology (2nd-CASAM) Evolution Benchmark Model Exact and Efficient Computation of First- and Second-Order Response Sensitivities
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Second-Order Adjoint Sensitivity Analysis Methodology for Computing Exactly Response Sensitivities to Uncertain Parameters and Boundaries of Linear Systems: Mathematical Framework 被引量:3
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作者 Dan Gabriel Cacuci 《American Journal of Computational Mathematics》 2020年第3期329-354,共26页
This work presents the “Second-Order Comprehensive Adjoint Sensitivity Analysis Methodology (2<sup>nd</sup>-CASAM)” for the efficient and exact computation of 1<sup>st</sup>- and 2<sup>... This work presents the “Second-Order Comprehensive Adjoint Sensitivity Analysis Methodology (2<sup>nd</sup>-CASAM)” for the efficient and exact computation of 1<sup>st</sup>- and 2<sup>nd</sup>-order response sensitivities to uncertain parameters and domain boundaries of linear systems. The model’s response (<em>i.e.</em>, model result of interest) is a generic nonlinear function of the model’s forward and adjoint state functions, and also depends on the imprecisely known boundaries and model parameters. In the practically important particular case when the response is a scalar-valued functional of the forward and adjoint state functions characterizing a model comprising N parameters, the 2<sup>nd</sup>-CASAM requires a single large-scale computation using the First-Level Adjoint Sensitivity System (1<sup>st</sup>-LASS) for obtaining all of the first-order response sensitivities, and at most N large-scale computations using the Second-Level Adjoint Sensitivity System (2<sup>nd</sup>-LASS) for obtaining exactly all of the second-order response sensitivities. In contradistinction, forward other methods would require (<em>N</em>2/2 + 3 <em>N</em>/2) large-scale computations for obtaining all of the first- and second-order sensitivities. This work also shows that constructing and solving the 2<sup>nd</sup>-LASS requires very little additional effort beyond the construction of the 1<sup>st</sup>-LASS needed for computing the first-order sensitivities. Solving the equations underlying the 1<sup>st</sup>-LASS and 2<sup>nd</sup>-LASS requires the same computational solvers as needed for solving (<em>i.e.</em>, “inverting”) either the forward or the adjoint linear operators underlying the initial model. Therefore, the same computer software and “solvers” used for solving the original system of equations can also be used for solving the 1<sup>st</sup>-LASS and the 2<sup>nd</sup>-LASS. Since neither the 1<sup>st</sup>-LASS nor the 2<sup>nd</sup>-LASS involves any differentials of the operators underlying the original system, the 1<sup>st</sup>-LASS is designated as a “<u>first-level</u>” (as opposed to a “first-order”) adjoint sensitivity system, while the 2<sup>nd</sup>-LASS is designated as a “<u>second-level</u>” (rather than a “second-order”) adjoint sensitivity system. Mixed second-order response sensitivities involving boundary parameters may arise from all source terms of the 2<sup>nd</sup>-LASS that involve the imprecisely known boundary parameters. Notably, the 2<sup>nd</sup>-LASS encompasses an automatic, inherent, and independent “solution verification” mechanism of the correctness and accuracy of the 2nd-level adjoint functions needed for the efficient and exact computation of the second-order sensitivities. 展开更多
关键词 Second-Order comprehensive Adjoint Sensitivity analysis Methodology (2nd-CASAM) First-Level Adjoint Sensitivity System (1st-LASS) Second-Level Adjoint Sensitivity System (2nd-LASS) Operator-Type Response Second-Order Sensitivities to Uncertain Model Boundaries Second-Order Sensitivities to Uncertain Model Parameters
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Influence of Wall Effect on Comprehensive Controllability for Ducted Fan Aircraft
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作者 Tianfu Ai Changle Xiang +2 位作者 Bin Xu Wei Fan Yibo Zhang 《Journal of Beijing Institute of Technology》 EI CAS 2020年第4期581-591,共11页
A novel coaxial ducted fan structure aircraft is proposed to enable the aircraft near vertical walls at high altitudes.The state space equation of the system can be obtained by correlation deduction and identification... A novel coaxial ducted fan structure aircraft is proposed to enable the aircraft near vertical walls at high altitudes.The state space equation of the system can be obtained by correlation deduction and identification of the whole prototype model.Based on the duct test bench experiment and computational fluid dynamics(CFD)simulation analysis,the expressions between the different distances dWE from the rotor center of the prototype to the wall and the thrust,reaction torque,and tilting moment of the system under hovering conditions are obtained.The influence of the wall effect of the prototype is incorporated into the system model to analyze the relationship between distance dWE and the comprehensive controllability of the system.The results show that the system comprehensive controllability vector of other channels changes little with the decrease of the distance dWE,and only the controllability vector of the rolling channel increases significantly.At the same time,the tilting moment also increases significantly,which strengthens the tendency of the prototype to tilt towards the wall. 展开更多
关键词 coaxial ducted fan aircraft hovering condition wall effect tilting moment comprehensive controllability analysis
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