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Fe(Ⅱ)对CANON工艺处理城镇污水脱氮性能的影响
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作者 张倩倩 廖祖刚 +3 位作者 冯泽通 刘金泽 符文婧 赵剑强 《安全与环境工程》 CAS CSCD 北大核心 2024年第2期291-300,共10页
全程自养脱氮(CANON)工艺,作为新型脱氮工艺应用于城镇污水深度脱氮过程中,有望降低污水处理的运行费用。考察了亚铁离子[Fe(Ⅱ)]对CANON工艺启动及稳定运行时脱氮性能的影响。结果表明:15~23℃条件下投加6.3 mg/L Fe(Ⅱ)时,可有效启动... 全程自养脱氮(CANON)工艺,作为新型脱氮工艺应用于城镇污水深度脱氮过程中,有望降低污水处理的运行费用。考察了亚铁离子[Fe(Ⅱ)]对CANON工艺启动及稳定运行时脱氮性能的影响。结果表明:15~23℃条件下投加6.3 mg/L Fe(Ⅱ)时,可有效启动并稳定运行CANON工艺处理城镇污水,该工艺氮去除负荷(NRR)、总氮去除率(TNRE)和氨氮去除率(ARE)分别为(4.8±1.1)g-N/(L^(3)·d)、(97±1)%和(44.2±9.3)%;相关性分析表明,通过调控Fe(Ⅱ)投加量可有效抑制亚硝酸盐氧化菌(NOB)的活性;本次优化的Fe(Ⅱ)投加量为6.3 mg/L,其对CANON工艺脱氮性能的影响机制与CANON工艺中功能微生物活性的提高、Fe(Ⅱ)与进水氨氮及其他氮化合物的循环反应、铁型反硝化过程以及铁型厌氧氨氧化过程的耦合有关。 展开更多
关键词 canon工艺 城镇污水 Fe(Ⅱ) 脱氮效能
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CRABP1-mediated non-canonical retinoic acid signaling in motor neurons and neural stem cells
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作者 Li-Na Wei 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第6期1169-1170,共2页
Retinoic acid(RA),the active metabolite of vitamin A(the retinoids),elicits a wide spectrum of biological activities critical to the development and health of most of the organ systems including the nervous systems(Co... Retinoic acid(RA),the active metabolite of vitamin A(the retinoids),elicits a wide spectrum of biological activities critical to the development and health of most of the organ systems including the nervous systems(Corcoran et al.,2002).The effects of RA are mediated by two very distinct pathways;the first is manifested in the nucleus by binding to a large family of nuclear RA receptors(RARs)to regulate proper expression of RAtargeted genes. 展开更多
关键词 canonICAL SPECTRUM CRITICAL
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Cross-Project Software Defect Prediction Based on SMOTE and Deep Canonical Correlation Analysis
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作者 Xin Fan Shuqing Zhang +2 位作者 Kaisheng Wu Wei Zheng Yu Ge 《Computers, Materials & Continua》 SCIE EI 2024年第2期1687-1711,共25页
Cross-Project Defect Prediction(CPDP)is a method that utilizes historical data from other source projects to train predictive models for defect prediction in the target project.However,existing CPDP methods only consi... Cross-Project Defect Prediction(CPDP)is a method that utilizes historical data from other source projects to train predictive models for defect prediction in the target project.However,existing CPDP methods only consider linear correlations between features(indicators)of the source and target projects.These models are not capable of evaluating non-linear correlations between features when they exist,for example,when there are differences in data distributions between the source and target projects.As a result,the performance of such CPDP models is compromised.In this paper,this paper proposes a novel CPDP method based on Synthetic Minority Oversampling Technique(SMOTE)and Deep Canonical Correlation Analysis(DCCA),referred to as S-DCCA.Canonical Correlation Analysis(CCA)is employed to address the issue of non-linear correlations between features of the source and target projects.S-DCCA extends CCA by incorporating the MlpNet model for feature extraction from the dataset.The redundant features are then eliminated by maximizing the correlated feature subset using the CCA loss function.Finally,cross-project defect prediction is achieved through the application of the SMOTE data sampling technique.Area Under Curve(AUC)and F1 scores(F1)are used as evaluation metrics.This paper conducted experiments on 27 projects from four public datasets to validate the proposed method.The results demonstrate that,on average,our method outperforms all baseline approaches by at least 1.2%in AUC and 5.5%in F1 score.This indicates that the proposed method exhibits favorable performance characteristics. 展开更多
关键词 Cross-project defect prediction deep canonical correlation analysis feature similarity
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The Publication of the Piling Canon in the Late Qing
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作者 LIU Yi 《Cultural and Religious Studies》 2024年第9期566-574,共9页
Piling Canon refers to a woodblock-printed Chinese Buddhist Canon during the late Qing Dynasty.Despite its historical significance,it has received limited attention from the academia,as its discovery took place after ... Piling Canon refers to a woodblock-printed Chinese Buddhist Canon during the late Qing Dynasty.Despite its historical significance,it has received limited attention from the academia,as its discovery took place after the turn of the 21st century.This study explores the background,supervisor,proofreader,engravers,donors,and other factors that contributed to the publication of the Piling Canon.It was supervised by Buddhist monk Qingrong in Changzhou Tianning Monastery from 1908 to 1926,due to the commission of Yang Wenhui.By investigating the historical records in the colophons of Piling Canon,we found that engraving locations are distributed in Hubei,Yangzhou,and Danyang which engravers operated in groups;the majority of donors were found to be individuals and group forms,social fundraising was included as well.It is noteworthy that Sheng Xuanhuai made a significant contribution in terms of funding.Furthermore,the production of the Piling Canon confirms to the commence of Buddhism revival,as Buddhist scriptures in Jiangnan regions were almost destroyed after the Taiping Rebellion.The research shed light on extensive participation of cultural celebrities,diverse donation forms,and excellent engraving,offering a vivid depiction of Buddhist belief and social landscape in Jiangnan region. 展开更多
关键词 Piling canon Buddhist scriptures Tianning Monastery DONORS Jiangnan
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Crosstalk among canonical Wnt and Hippo pathway members in skeletal muscle and at the neuromuscular junction
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作者 Said Hashemolhosseini Lea Gessler 《Neural Regeneration Research》 SCIE CAS 2025年第9期2464-2479,共16页
Skeletal muscles are essential for locomotion,posture,and metabolic regulation.To understand physiological processes,exercise adaptation,and muscle-related disorders,it is critical to understand the molecular pathways... Skeletal muscles are essential for locomotion,posture,and metabolic regulation.To understand physiological processes,exercise adaptation,and muscle-related disorders,it is critical to understand the molecular pathways that underlie skeletal muscle function.The process of muscle contra ction,orchestrated by a complex interplay of molecular events,is at the core of skeletal muscle function.Muscle contraction is initiated by an action potential and neuromuscular transmission requiring a neuromuscular junction.Within muscle fibers,calcium ions play a critical role in mediating the interaction between actin and myosin filaments that generate force.Regulation of calcium release from the sarcoplasmic reticulum plays a key role in excitation-contraction coupling.The development and growth of skeletal muscle are regulated by a network of molecular pathways collectively known as myogenesis.Myogenic regulators coordinate the diffe rentiation of myoblasts into mature muscle fibers.Signaling pathways regulate muscle protein synthesis and hypertrophy in response to mechanical stimuli and nutrient availability.Seve ral muscle-related diseases,including congenital myasthenic disorders,sarcopenia,muscular dystrophies,and metabolic myopathies,are underpinned by dys regulated molecular pathways in skeletal muscle.Therapeutic interventions aimed at preserving muscle mass and function,enhancing regeneration,and improving metabolic health hold promise by targeting specific molecular pathways.Other molecular signaling pathways in skeletal muscle include the canonical Wnt signaling pathway,a critical regulator of myogenesis,muscle regeneration,and metabolic function,and the Hippo signaling pathway.In recent years,more details have been uncovered about the role of these two pathways during myogenesis and in developing and adult skeletal muscle fibers,and at the neuromuscular junction.In fact,research in the last few years now suggests that these two signaling pathways are interconnected and that they jointly control physiological and pathophysiological processes in muscle fibers.In this review,we will summarize and discuss the data on these two pathways,focusing on their concerted action next to their contribution to skeletal muscle biology.However,an in-depth discussion of the noncanonical Wnt pathway,the fibro/a dipogenic precursors,or the mechanosensory aspects of these pathways is not the focus of this review. 展开更多
关键词 canonical Wnt"Wingless-related integration site"pathway beta-catenin(CTNNB1) Hippo pathway MYOGENESIS MYOTUBE neuromuscular junction satellite cell skeletal muscle fiber transcriptional co-activator with PDZ-binding motif(TAZ) T-cell-specific transcription factor/lymphoid enhancer-binding factor(TCF/LEF) TEA domain family member(TEAD) transducin-like enhancer of split(TLE) yes-associated protein 1(YAP1)
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水力条件对CANON工艺颗粒污泥特性的影响研究
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作者 漆磊 《四川环境》 2023年第5期25-30,共6页
为实现自养生物脱氮,采用膨胀颗粒污泥床小试反应器(R1~R3)培养全程自养脱氮工艺(Completely Autotrophic Nitrogen Removal Over Nitrite, CANON)颗粒污泥,考察了不同上升流速、水力剪切力和溶解氧浓度下CANON颗粒污泥浓度和粒径的变... 为实现自养生物脱氮,采用膨胀颗粒污泥床小试反应器(R1~R3)培养全程自养脱氮工艺(Completely Autotrophic Nitrogen Removal Over Nitrite, CANON)颗粒污泥,考察了不同上升流速、水力剪切力和溶解氧浓度下CANON颗粒污泥浓度和粒径的变化规律。结果表明:系统稳定后,污泥浓度呈现出R2>R1>R3,R1、R2成功实现CANON颗粒污泥启动,并且实现了颗粒化,而R3中较高的上升流速、水力剪切力导致系统内污泥易碎裂从而洗出系统,导致R3未能启动成功。 展开更多
关键词 canon工艺 颗粒污泥 剪切力 污泥浓度 污泥粒径
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长期-短期饥饿对CANON工艺启动的影响
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作者 杨综艺 李军 +2 位作者 张凯 高鹏 唐鹏 《中国环境科学》 EI CAS CSCD 北大核心 2023年第7期3429-3437,共9页
采用序批式反应器(SBR)启动全程自养脱氮(CANON)工艺,考察启动过程中长期饥饿胁迫和短期饥饿调控对脱氮效果的影响,对短期饥饿前后功能菌活性进行测试,分析在缩短恢复时间下反复进行短期饥饿对亚硝酸盐氧化菌(NOB)的抑制作用,对CANON启... 采用序批式反应器(SBR)启动全程自养脱氮(CANON)工艺,考察启动过程中长期饥饿胁迫和短期饥饿调控对脱氮效果的影响,对短期饥饿前后功能菌活性进行测试,分析在缩短恢复时间下反复进行短期饥饿对亚硝酸盐氧化菌(NOB)的抑制作用,对CANON启动过程中的不同阶段进行微生物测序,分析群落结构的变化情况.结果表明,长期饥饿后系统在7d恢复运行时,TN去除率(NRE)可达到62.34%.短期饥饿-恢复模式加快了工艺的启动速度,成功将SBR中ΔNO_(3)^(-)-N/ΔNH_(4)^(+)-N控制在0.11左右.在实现启动时,工艺平均氨氮去除率(ARE)超过95%,平均NRE可达79.45%.采用短期饥饿调控前后,NOB活性由91.32mgN/(gVSS·d)降至45.40mgN/(gVSS·d),比厌氧氨氧化活性(SAA)升高至219.25mgN/(gVSS·d),保证了CANON脱氮性能.高通量测序表明,在经历长期饥饿后,好氧氨氧化菌(AerAOB)功能菌Nitrosomonas能够迅速恢复.Candidatus Kuenenia具有抵抗长期饥饿的能力,在7d恢复运行后,相对丰度高达69.04%,在稳定恢复运行中,丰度有所降低,但在工艺启动后丰度达到61.19%,实现了厌氧氨氧化菌(AnAOB)的富集.CANON工艺能够在长期饥饿胁迫中恢复,短期饥饿调控有利于提高工艺效能. 展开更多
关键词 全程自养脱氮(canon) 长期饥饿 功能菌活性 亚硝酸盐氧化菌(NOB)
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低C/N比CANON工艺脱氮机制分析
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作者 田亮 黄锐 +1 位作者 杜冬云 吴晨捷 《环境科学与技术》 CAS CSCD 北大核心 2023年第10期104-111,共8页
该文在微氧升流反应器中构建颗粒-絮体污泥体系,以乙酸钠作为碳源,探究了C/N对CANON工艺脱氮效率的影响,并分析了低C/N下该工艺的脱氮机制。当C/N=0.75时,TN和NH_(4)^(+)-N去除率达到了最高值92%和95%。而当C/N从0.75增长至1时,TN和NH_(... 该文在微氧升流反应器中构建颗粒-絮体污泥体系,以乙酸钠作为碳源,探究了C/N对CANON工艺脱氮效率的影响,并分析了低C/N下该工艺的脱氮机制。当C/N=0.75时,TN和NH_(4)^(+)-N去除率达到了最高值92%和95%。而当C/N从0.75增长至1时,TN和NH_(4)^(+)-N去除率分别下降至80%和85%;C/N回调至0.75后,10 d左右反应器性能恢复至91%TN去除率。C/N=0.75时脱氮贡献分析和粒度分布表明AnAOB对NO_(2)^(-)-N的摄取处于优势地位,反应器内主要发生Anammox反应和短程反硝化反应,合适的C/N并不会导致异养菌取代AnAOB的优势地位,且Anammox反应的脱氮贡献在56%~62%之间。 展开更多
关键词 微氧升流反应器 canon工艺 颗粒-絮体污泥 脱氮机制 低C/N
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3-D Gait Identification Utilizing Latent Canonical Covariates Consisting of Gait Features 被引量:1
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作者 Ramiz Gorkem Birdal Ahmet Sertbas 《Computers, Materials & Continua》 SCIE EI 2023年第9期2727-2744,共18页
Biometric gait recognition is a lesser-known but emerging and effective biometric recognition method which enables subjects’walking patterns to be recognized.Existing research in this area has primarily focused on fe... Biometric gait recognition is a lesser-known but emerging and effective biometric recognition method which enables subjects’walking patterns to be recognized.Existing research in this area has primarily focused on feature analysis through the extraction of individual features,which captures most of the information but fails to capture subtle variations in gait dynamics.Therefore,a novel feature taxonomy and an approach for deriving a relationship between a function of one set of gait features with another set are introduced.The gait features extracted from body halves divided by anatomical planes on vertical,horizontal,and diagonal axes are grouped to form canonical gait covariates.Canonical Correlation Analysis is utilized to measure the strength of association between the canonical covariates of gait.Thus,gait assessment and identification are enhancedwhenmore semantic information is available through CCA-basedmulti-feature fusion.Hence,CarnegieMellon University’s 3D gait database,which contains 32 gait samples taken at different paces,is utilized in analyzing gait characteristics.The performance of Linear Discriminant Analysis,K-Nearest Neighbors,Naive Bayes,Artificial Neural Networks,and Support Vector Machines was improved by a 4%average when the CCA-utilized gait identification approachwas used.Asignificant maximumaccuracy rate of 97.8%was achieved throughCCA-based gait identification.Beyond that,the rate of false identifications and unrecognized gaits went down to half,demonstrating state-of-the-art for gait identification. 展开更多
关键词 Gait identification canonical covariates multivariate data analysis gait determinant
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An Update Method of Decision Implication Canonical Basis on Attribute Granulating 被引量:1
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作者 Yanhui Zhai Rujie Chen Deyu Li 《Intelligent Automation & Soft Computing》 SCIE 2023年第8期1833-1851,共19页
Decision implication is a form of decision knowledge represen-tation,which is able to avoid generating attribute implications that occur between condition attributes and between decision attributes.Compared with other... Decision implication is a form of decision knowledge represen-tation,which is able to avoid generating attribute implications that occur between condition attributes and between decision attributes.Compared with other forms of decision knowledge representation,decision implication has a stronger knowledge representation capability.Attribute granularization may facilitate the knowledge extraction of different attribute granularity layers and thus is of application significance.Decision implication canonical basis(DICB)is the most compact set of decision implications,which can efficiently represent all knowledge in the decision context.In order to mine all deci-sion information on decision context under attribute granulating,this paper proposes an updated method of DICB.To this end,the paper reduces the update of DICB to the updates of decision premises after deleting an attribute and after adding granulation attributes of some attributes.Based on this,the paper analyzes the changes of decision premises,examines the properties of decision premises,designs an algorithm for incrementally generating DICB,and verifies its effectiveness through experiments.In real life,by using the updated algorithm of DICB,users may obtain all decision knowledge on decision context after attribute granularization. 展开更多
关键词 Decision context attribute granulating decision implication decision implication canonical basis
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Cohen-Macaulay局部环上的Canonical模
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作者 路姣姣 杨晓燕 《吉林大学学报(理学版)》 CAS 北大核心 2023年第1期61-65,共5页
令(R,m,k)是Cohen-Macaulay局部环,M,N是有限生成R-模.假设N∈ΩCM(R),且Ext_(R)^(1≤i≤d)(M,N)=0,证明HomR(M,N)∈ΩCM(R),并给出有限生成模N是canonical模的条件.
关键词 Cohen-Macaulay局部环 极大Cohen-Macaulay模 canonical模
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Drivers of Forecasting the Behavioral Intention and Acceptance Behavior of the Hail Canon Technology(HCT): Using Logistic and System Dynamics Modeling
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作者 ABADI Bijan HAGHANINIA Mohammad 《Chinese Geographical Science》 SCIE CSCD 2023年第3期549-564,共16页
Globally known about the drivers through which farmers are instigated to uphold and use Hail Canon Technology(HCT)is lacking.Therefore,this article intended to examine the drivers of forecasting the behavioral intenti... Globally known about the drivers through which farmers are instigated to uphold and use Hail Canon Technology(HCT)is lacking.Therefore,this article intended to examine the drivers of forecasting the behavioral intention and acceptance behavior of the HCT,249 apple farmers from northwestern Iran were recruited,including adopters(n1=114)and non-adopters(n2=135).The conceptual foundation included demographic theory,resource-based theory,theory of planned behavior,innovation diffusion model,and institutional support model.We also used the system dynamics model(SDM)in the Netlogo to assess the results of the conventional statistical approach(i.e.,the logistic model).Authenticated the fitness of conceptual model with the data,logistic model manifests that the most outstanding determinants of the acceptance of HCT entail age,experience,total land size,income,attitude,compatibility,visibility,relative advantage,and financial support.Using the SDM,it was also shown that the results of the logistic model are confirmed by the SDM.In conclusion,management implications are available for the university extension to eliminate the adoption obstacles and stir up farmers to join in applying HCT,furthermore,researchers would avail themselves of remarks for future research. 展开更多
关键词 canon VISIBILITY furthermore
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Grand canonical Monte Carlo simulation study of hydrogen storage by Li-decorated pha-graphene
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作者 张蒙蒙 张凤 +7 位作者 吴强 黄欣 闫巍 赵春梅 陈伟 杨志红 王允辉 武婷婷 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第6期476-480,共5页
Grand canonical Monte Carlo simulation(GCMCs)is utilized for studying hydrogen storage gravimetric density by pha-graphene at different metal densities,temperatures and pressures.It is demonstrated that the optimum ad... Grand canonical Monte Carlo simulation(GCMCs)is utilized for studying hydrogen storage gravimetric density by pha-graphene at different metal densities,temperatures and pressures.It is demonstrated that the optimum adsorbent location for Li atoms is the center of the seven-membered ring of pha-graphene.The binding energy of Li-decorated phagraphene is larger than the cohesive energy of Li atoms,implying that Li can be distributed on the surface of pha-graphene without forming metal clusters.We fitted the force field parameters of Li and C atoms at different positions and performed GCMCs to study the absorption capacity of H_(2).The capacity of hydrogen storage was studied by the differing density of Li decoration.The maximum hydrogen storage capacity of 4Li-decorated pha-graphene was 15.88 wt%at 77 K and100 bar.The enthalpy values of adsorption at the three densities are in the ideal range of 15 kJ·mol^(-1)-25 kJ·mol^(-1).The GCMC results at different pressures and temperatures show that with the increase in Li decorative density,the hydrogen storage gravimetric ratio of pha-graphene decreases but can reach the 2025 US Department of Energy's standard(5.5 wt%).Therefore,pha-graphene is considered to be a potential hydrogen storage material. 展开更多
关键词 hydrogen storage pha-graphene grand canonical Monte Carlo simulation(GCMCs) force field
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Analysis of Differential Gene Expression and Core Canonical Pathways Involved in the Epithelial to Mesenchymal Transition of Triple Negative Breast Cancer Cells by Ingenuity Pathway Analysis
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作者 Elizabeth Cagle Brent Lake +10 位作者 Anasua Banerjee Jazmine Cuffee Narendra Banerjee Darla Gilmartin Makaiyah Liverman Shennel Brown Erik Armstrong Santanu Bhattacharya Somiranjan Ghosh Tanmoy Mandal Hirendra Banerjee 《Computational Molecular Bioscience》 2023年第2期21-34,共14页
Triple Negative Breast Cancer (TNBC) is a malignant form of cancer with very high mortality and morbidity. Epithelial to Mesenchymal Transition (EMT) is the most common pathophysiological change observed in cancer cel... Triple Negative Breast Cancer (TNBC) is a malignant form of cancer with very high mortality and morbidity. Epithelial to Mesenchymal Transition (EMT) is the most common pathophysiological change observed in cancer cells of epithelial origin that promotes metastasis, drug resistance and cancer stem cell formation. Since the information regarding differential gene expression in TNBC cells and cell signaling events leading to EMT is limited, this investigation was done by comparing transcriptomic data generated by RNA isolation and sequencing of a EMT model TNBC cell line in comparison to regular TNBC cells. RNA sequencing and Ingenuity Pathway Software Analysis (IPA) of the transcriptomic data revealed several upregulated and downregulated gene expressions along with novel core canonical pathways including Sirtuin signaling, Oxidative Phosphorylation and Mitochondrial dysfunction events involved in EMT changes of the TNBC cells. 展开更多
关键词 Triple Negative Breast Cancer Epithelial to Mesenchymal Transition Core canonical Pathways
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基于Canonical最小二乘蒙特卡罗法的可转债定价
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作者 殷炼乾 皮蓉 《债券》 2023年第12期91-97,共7页
区别于传统的最小二乘蒙特卡罗方法,本文利用标的资产收益率生成Canonical风险中性概率计算累计概率分布函数进行抽样,以此生成标的资产价格的蒙特卡罗路径。同时,运用平赌过程适配法对蒙特卡罗模拟进行改进,以提高模型的收敛速度并降... 区别于传统的最小二乘蒙特卡罗方法,本文利用标的资产收益率生成Canonical风险中性概率计算累计概率分布函数进行抽样,以此生成标的资产价格的蒙特卡罗路径。同时,运用平赌过程适配法对蒙特卡罗模拟进行改进,以提高模型的收敛速度并降低其误差。针对可转债的特殊条款,本文按照市场惯例及逻辑,将回售条款与下修条款结合处理,以提高模型的可行性和运算效率。最后,使用传统的参数化方法进行对比实验。结果表明,本文所设计方法的模拟路径比传统方法更能体现标的资产的运动特性,定价结果优于传统的参数化方法。 展开更多
关键词 可转债定价 最小二乘蒙特卡罗 canonical风险中性概率 平赌过程适配法
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基于蒙特卡罗的硫化氢吸附-扩散机理 被引量:1
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作者 贾进章 邢迎欢 +4 位作者 李斌 贾鹏 吴禹默 杨强 王东明 《煤炭学报》 EI CAS CSCD 北大核心 2024年第2期845-864,共20页
为了明确硫化氢(H_(2)S)在煤中吸附扩散的微观动力学机理,揭示不同温度、压力对煤吸附H_(2)S分子吸附扩散特性的影响机制,基于巨正则蒙特卡罗(GCMC)、分子动力学(MD)和密度泛函理论(DFT)方法,利用Material Studio软件研究了温度在273.15... 为了明确硫化氢(H_(2)S)在煤中吸附扩散的微观动力学机理,揭示不同温度、压力对煤吸附H_(2)S分子吸附扩散特性的影响机制,基于巨正则蒙特卡罗(GCMC)、分子动力学(MD)和密度泛函理论(DFT)方法,利用Material Studio软件研究了温度在273.15~313.15 K、压力1~1 000 kPa时H_(2)S在气肥煤大分子模型中的吸附扩散特征。结果表明:温度由273.15 K升至313.15 K时,H_(2)S的饱和吸附量由38.34 mL/g降至31.85 mL/g,降低了16.93%,当压力为1 kPa时,温度对吸附量的影响最为敏感。温度为293.15 K时,压力由1 kPa升至1 000 kPa时,最可几相互作用能由-39.391 kJ/mol升至-34.301 kJ/mol,随着压力的增加,最可几相互作用能先快速增加,后缓慢增加。在吸附H_(2)S过程中,H_(2)S的等量吸附热在36.63~41.43 kJ/mol内,为物理吸附,等量吸附热随着吸附量的增加呈现出负指数变化;H_(2)S的吉布斯自由能ΔG为-3.57~-24.57 kJ/mol,吸附熵ΔS为-0.126~-0.194 8 kJ/(mol·K),随吸附量升高ΔG和ΔS的绝对值线性降低,H_(2)S的吸附自发性和系统的混沌程度均降低。H_(2)S与气肥煤的相互作用能为-492.47~-3 390.95 kJ/mol,以范德华能为主,占总能量的58.67%,以静电能为辅,占41.33%,随着吸附量的增加,相互作用能绝对值增加,吸附量与相互作用能的变化具有一致性。H_(2)S与羧基的相互作用最强,羟基次之,H_(2)S在—OH、—COOH、—C=O周围存在双层吸附。温度由273.15 K升至313.15 K,H_(2)S分子的扩散系数由1.066×10^(-10)m^(2)/s升至2.025×10^(-10)m^(2)/s,温度升高会导致原本闭合的孔吼孔道打开,增加裂隙的连通性,温度升高,增加H_(2)S分子平均自由程,使得H_(2)S扩散能力增强,H_(2)S扩散活化能为11.206 kJ/mol。H_(2)S相对体积分数分布呈现多峰结构,H_(2)S在气肥煤大分子模型中呈层状结构分布。H_(2)S的极限吸附热为42.898 kJ/mol,H_(2)S与煤体上—OH、—COOH、—C=O活性基团产生氢键作用,H_(2)S在吸附初期存在微弱的化学吸附。 展开更多
关键词 硫化氢 吸附-扩散 巨正则蒙特卡罗 分子模拟 吸附机理
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南京明城墙绿带草本层自生植物群落数量分类与排序分析 被引量:1
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作者 刘倩 丁彦芬 +2 位作者 宋杉杉 许文婕 杨威 《草业学报》 CSCD 北大核心 2024年第5期1-15,共15页
探索南京明城墙绿带草本层自生植物群落类型及其分布情况,确定影响其群落分布的主要环境因子,旨在为构建南京明城墙沿线绿色生态廊道及加强对于明城墙的保护提供理论依据。以南京明城墙绿带内30个样点为研究对象,基于南京明城墙绿带的... 探索南京明城墙绿带草本层自生植物群落类型及其分布情况,确定影响其群落分布的主要环境因子,旨在为构建南京明城墙沿线绿色生态廊道及加强对于明城墙的保护提供理论依据。以南京明城墙绿带内30个样点为研究对象,基于南京明城墙绿带的野外调查数据,以物种重要值为指标,运用α多样性指数分析草本层自生植物的物种多样性特征,采用平均聚合聚类(UPGMA)和典范对应分析(CCA)进行数量分类与排序,研究南京明城墙绿带草本层自生植物群落组成、分布及其与环境因子的关系。结果表明:1)南京明城墙绿带草本层自生植物的物种多样性指数和均匀度指数均较高,且物种分布较为均匀;2)UPGMA聚类将明城墙绿带草本层自生植物分为棕榈-常春藤婆婆纳+中华薹草+黄鹌菜群落、繁缕+紫堇+诸葛菜+阿拉伯婆婆纳群落、常春藤婆婆纳+野芝麻+繁缕+紫堇群落、鹅观草+野芝麻+诸葛菜+紫堇群落、络石-鹅观草+常春藤婆婆纳+加拿大一枝黄花群落、天葵+繁缕+野芝麻+猪殃殃群落、络石-野芝麻+诸葛菜+南赤瓟群落、蓬蘽+络石-渐尖毛蕨+鹅观草群落、野芝麻+鹅观草+求米草+青绿薹草群落、络石-野芝麻+常春藤婆婆纳+诸葛菜群落、野蔷薇+络石+厚萼凌霄-茜草群落11组类型;3)CCA排序结果显示,影响南京明城墙绿带草本层自生植物群落分布的主要环境因子是郁闭度、枯落物厚度、墙体高度及墙面朝向。 展开更多
关键词 南京明城墙 草本层自生植物 物种多样性 群落分类 典范对应分析
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基于PSD特征的FBCCA脑电信号识别方法 被引量:1
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作者 张学军 杨京儒 《科学技术与工程》 北大核心 2024年第4期1411-1417,共7页
当前基于稳态视觉诱发电位(steady-state visual evoked potential,SSVEP)的脑机接口(brain-computer interfaces,BCIs)使用的都是单一识别算法,针对不同时间长度的识别准确率较低。提出了一种基于滤波器组的典型相关分析(filter bank c... 当前基于稳态视觉诱发电位(steady-state visual evoked potential,SSVEP)的脑机接口(brain-computer interfaces,BCIs)使用的都是单一识别算法,针对不同时间长度的识别准确率较低。提出了一种基于滤波器组的典型相关分析(filter bank canonical correlation analysis,FBCCA)与功率谱密度(power spectral density,PSD)分析相结合的SSVEP识别算法,可以提高SSVEP识别的普适性与准确率。该方法使用FBCCA寻找高相似度的参考频率信号,再通过多组PSD分析来锁定最终的响应频率,完成频率识别。该方法无需经过训练就能得到较高的识别准确率。实验结果表明:在刺激时长为1 s时,该方法能达到86.61%的准确率,比PSD分析方法提升了5.44%,比典型相关性分析方法(canonical correlation analysis,CCA)提升了10.38%的准确率,比FBCCA提升了8.86%的准确率。 展开更多
关键词 脑机接口(BCI) 稳态视觉诱发电位(SSVEP) 滤波器组的典型相关分析(FBCCA) 功率谱密度(PSD) 频率识别
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基于UPLC指纹图谱和多组分化学计量学探究白及饮片变色对其质量的影响
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作者 张佳 袁金凤 +5 位作者 柴冲冲 宋宜燕 燕姝羽 陈意淋 刘娜 李飞 《天津中医药》 CAS 2024年第8期1039-1046,共8页
[目的]探究白及饮片变绿对其质量的影响,明确主要化学成分变化和外观颜色的关联规律。[方法]采用CM-5型测色仪测定白及饮片的色度值,通过荧光法检测黄曲霉毒素,并建立超高效液相色谱法(UPLC)指纹图谱,进行多成分的含量测定,利用正交偏... [目的]探究白及饮片变绿对其质量的影响,明确主要化学成分变化和外观颜色的关联规律。[方法]采用CM-5型测色仪测定白及饮片的色度值,通过荧光法检测黄曲霉毒素,并建立超高效液相色谱法(UPLC)指纹图谱,进行多成分的含量测定,利用正交偏最小二乘判别分析(OPLS-DA)化学计量学方法探究影响白及颜色变化的差异性标志物,并将色度值和标志物含量进行典型相关性分析。[结果]通过对比5批白及正常和变绿饮片的色度值、多糖,以及8个特征峰的含量,发现多糖、白及苷、gymnosideⅢ、dactylorhin A可用于区分白及的正常饮片和颜色变绿饮片。典型相关分析表明,随着白及饮片变绿,L*、a*、E*值减小,b*值升高,白及苷、dactylorhin A、gymnosideⅢ以及多糖的含量均随之升高。[结论]白及饮片变绿后,多糖、白及苷等4种主要成分的含量明显增加,且和色度值具有显著的相关性,但颜色变化对其药效有何影响尚需进一步研究。 展开更多
关键词 白及 色度值 指纹图谱 白及苷 典型相关性分析
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宣和猪生长与胴体性状的典型相关分析
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作者 王孝义 赖金花 +4 位作者 鲁绍雄 卢薇霖 陈强 何家书 李明丽 《江西农业学报》 CAS 2024年第2期105-109,118,共6页
为了揭示宣和猪生长与胴体性状的内在关系,选择了122头体重30 kg左右的宣和仔猪,在相同饲养管理条件下育肥,测定其生长性能,在体重达100 kg左右时进行屠宰测定,并对7个生长性状和6个胴体性状进行Pearson相关与典型相关分析。结果表明:... 为了揭示宣和猪生长与胴体性状的内在关系,选择了122头体重30 kg左右的宣和仔猪,在相同饲养管理条件下育肥,测定其生长性能,在体重达100 kg左右时进行屠宰测定,并对7个生长性状和6个胴体性状进行Pearson相关与典型相关分析。结果表明:大多数生长性状之间的Pearson相关均达到显著水平(P<0.05或P<0.01),其中,料重比与平均日增重的相关系数最高(r=-0.5851,P<0.01);胴体瘦肉率与眼肌面积、后腿比例均呈极显著正相关(P<0.01);平均日增重、体长与胴体直长,胸围、活体背膘厚与平均背膘厚,宰前活重与屠宰率呈显著正相关(P<0.05或P<0.01),但料重比与平均背膘厚、胴体直长,体长、体高与胴体瘦肉率,胸围、活体背膘厚与后腿比例显著负相关(P<0.05或P<0.01)。生长与胴体性状的第1、第2对典型相关系数分别为0.6777(P<0.001)和0.4797(P<0.001),共解释总相关信息的79.79%;两类性状之间的典型相关主要是由料重比与屠宰率、平均背膘厚的相关所引起的。综上,在宣和猪育种实践中,选择料重比有助于提高宣和猪的生长速率,同时也可能会降低屠宰率和增加平均背膘厚。 展开更多
关键词 宣和猪 生长性状 胴体性状 Pearson相关 典型相关
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