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Quantifying the age peaks,age ranges and weights of detrital ages based on the EM algorithm
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作者 Jintao Kong 《Geoscience Frontiers》 SCIE CAS CSCD 2024年第4期217-229,共13页
Detrital geochronology fundamentally involves the quantification of major age ranges and their weights winthin an age distribution.This study presents a streamlined approach,modeling the age distribution of detrital z... Detrital geochronology fundamentally involves the quantification of major age ranges and their weights winthin an age distribution.This study presents a streamlined approach,modeling the age distribution of detrital zircons using a normal mixture model,and employs the Expectation-Maximization(EM)algorithm for precise estimations.A method is introduced to automatically select appropriate initial mean values for EM algorithm,enhancing its efficacy in detrital geochronology.This process entails multiple trials with varying numbers of age components leading to diverse k-component models.The model with the lowest Bayesian Information Criterion(BIC)is identified as the most suitable.For accurate component number and weight determination,a substantial sample size(n>200)is advisable. Our findings based on both synthetic and empirical datasets confirm that the normal mixture model,refined by the EM algorithm,reliably identifies key age parameters with minimal error.As a kind of probability density estimator,the normal mixture model offers a novel visualization tool for detrital data and an alternative foundation for KDE in calculating existing similarity metrics.Another focus of this study is the critical examination of quantitative metrics for comparing detrital zircon age patterns.Through a case study,this study demonstrates that metrics based on empirical cumulative probability distribution(such as K-S and Kuiper statistics)may lead to erroneous conclusions.The employment of the Kullback-Leibler(KL)divergence,a metric grounded in probability density estimation,is proposed.Reference critical values,simulated via the Monte Carlo method,provide more objective benchmarks for these quantitative metrics. All methodologies discussed are encapsulated in a series of MATLAB scripts,available as open-source code and a standalone application,facilitating wider adoption and application in the field. 展开更多
关键词 Detrital zircongeochronology Expectation-Maximization algorithm Kullback-Leibler divergence quantifying comparison Age peaks ageranges andweights
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Quantify测量法在融合媒介效果研究中的应用研究
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作者 丁迈 董光宇 《中国新闻传播研究》 2020年第2期213-225,共13页
在融合媒介背景下,基于问卷、实验方法的媒介效果测量方法,在测量行为、技术、成本和用户体验方面都面临着新的挑战。本研究尝试使用了一种名为"Quantify"的新测量方法,在结合实验、问卷的情况下,面向数字媒介对传统测量手段... 在融合媒介背景下,基于问卷、实验方法的媒介效果测量方法,在测量行为、技术、成本和用户体验方面都面临着新的挑战。本研究尝试使用了一种名为"Quantify"的新测量方法,在结合实验、问卷的情况下,面向数字媒介对传统测量手段进行了改进,并以"情绪指标"为测量对象,探索了这种方法在融合媒介传播效果研究中的应用可能性。本文认为,Quantify方法能够通过简单的用户行为,经过统计方法输出更高级别的测量结果,适用于当前用户时间碎片化、测量成本升高、传统方法信息价值下降的现实情境,适合融合媒介背景下跨屏幕效果测量的实际应用。 展开更多
关键词 quantify TrueSkill 效果研究 融合媒介
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Quantifying Rosette Formation Mediated by Receptor-ligand Interactions
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作者 Mian LONG(National Microgravity Laboratory, Institute of Mechanics, Chinese Academy of Sciences, Beijing 100080,China) 《生物医学工程学杂志》 EI CAS CSCD 北大核心 2005年第S1期35-36,共2页
关键词 quantifying Rosette Formation Mediated by Receptor-ligand Interactions RBCS CELL
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Study on noninvasively quantifying of pregnatal fetomaternal hemorrhage (FMH) by elow cytometry(FCM)
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《中国输血杂志》 CAS CSCD 2001年第S1期403-,共1页
关键词 FCM FMH by elow cytometry Study on noninvasively quantifying of pregnatal fetomaternal hemorrhage
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A Comprehensive Strategy to Quantify the Complex System by Ultraviolet and Infrared Spectra Analyses Coupled with Combustion Heat for Recognizing the Quality Consistency of San-Huang Tablets 被引量:1
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作者 Yan Wang Guoxiang Sun +3 位作者 Yang Jin Jing Zhang Jiayue Gao Eboka Majolene Benedicta Sabi-Mouka 《American Journal of Analytical Chemistry》 2017年第10期668-680,共13页
Spectral quantitative fingerprinting including ultraviolet (UV) and Fourier transform infrared (FT-IR) coupled with combustion heat (CH) analytical techniques was employed and compared for rapid screening quality grad... Spectral quantitative fingerprinting including ultraviolet (UV) and Fourier transform infrared (FT-IR) coupled with combustion heat (CH) analytical techniques was employed and compared for rapid screening quality grade and discriminating San-Huang Tablets (SHT) of different commercial brands. The systematic quantified fingerprint method (SQFM) was applied to evaluate, qualitatively and quantitatively, the quality consistency of the herbal preparation. It was possible to deduce that the quantitative similarity analysis by SQFM was enabled to make a good discrimination of the tested samples. It was a particularly useful method for the overall quality evaluation of herbal medicine and their preparations. 展开更多
关键词 Combustion Heat San-Huang TABLETS Spectral FINGERPRINT Systematic Quantified FINGERPRINT Method
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Quantifying bubble dynamics via fiber optic sensor for in situ electrocatalytic evaluation
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作者 Xian Wei Jiaqi Li +6 位作者 Wenhao Liang Chen Ma Tianfan Zhou Qi Zhang Longlu Wang Kehan Yu Wei Wei 《Nano Research》 2025年第9期1184-1192,共9页
The hydrogen evolution reaction(HER)in electrochemical water splitting is crucial for green hydrogen production,yet its efficiency is limited by bubble dynamics at the electrode surface.Accumulated bubbles can block a... The hydrogen evolution reaction(HER)in electrochemical water splitting is crucial for green hydrogen production,yet its efficiency is limited by bubble dynamics at the electrode surface.Accumulated bubbles can block active sites,hinder mass transport,and increase local resistance,causing energy loss.Thus,precise bubble monitoring is crucial for understanding performance limitations and optimizing catalyst design.Conventional bubble monitoring techniques,such as optical microscopy,high-speed imaging,and electrochemical impedance,are constrained by real-time accuracy,complex post-processing,or signal interference at high current densities.Here,we present an in situ fiber optic sensing system that enables precise,real-time monitoring of bubble dynamics during HER.Unlike traditional methods,this system leverages the sensitivity and real-time capability of fiber optic sensors to quantify key parameters,such as growth rate,detachment rate,intake/output ratio,and detaching size.Its reliability and adaptability were validated using two different Pt/C-loaded carbon paper catalysts with distinct catalytic properties.Notably,the system also achieves a bubble detection limit of 79μm,which meets the spatial resolution requirements for monitoring bubble dynamics relevant to electrocatalytic activity in HER.This sensing platform establishes a practical framework for connecting interfacial gas evolution to electrochemical performance,offering valuable insight for optimizing HER efficiency through catalyst design. 展开更多
关键词 bubble dynamics in situ monitoring fiber optic sensor ELECTROCATALYSIS quantified evaluation
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Changes in liver and spleen stiffness after transjugular intrahepatic portosystemic shunt and their relationship with prognosis
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作者 Xiao-Fang Liu Xiao-Chun Huang +4 位作者 Qian-Jun Ye Li-Jing Yuan Gui-Fang Gao Jin-Yu Li Dui-Ping Feng 《World Journal of Gastrointestinal Surgery》 2025年第8期338-349,共12页
BACKGROUND The impact of transjugular intrahepatic portosystemic shunt(TIPS)on liver and spleen stiffness remains unclear,as does the association between preoperative liver and spleen stiffness and prognosis following... BACKGROUND The impact of transjugular intrahepatic portosystemic shunt(TIPS)on liver and spleen stiffness remains unclear,as does the association between preoperative liver and spleen stiffness and prognosis following TIPS.AIM To investigate changes in liver and spleen stiffness after TIPS and examines the relationship between these parameters and the prognosis of post-TIPS patients.METHODS A total of 76 patients with liver cirrhosis and portal hypertension who underwent TIPS were included.Liver and spleen stiffness was assessed using the sound touch quantify(STQ)value,determined via point shear wave elastography in ultrasound imaging.Cox regression analysis was employed to evaluate the relationship between liver and spleen stiffness and cumulative survival in TIPS patients.RESULTS The liver STQ value demonstrated a marginally decreasing trend over time(P=0.052),while the spleen STQ value showed a significantly decreasing trend(P=0.025).Spleen STQ was positively correlated with portal pressure gradient(PPG)levels(rs=0.327,P=0.025).Cox regression analysis indicated that older age[hazard ratio(HR)=1.063,95%CI:0.997-1.133,P=0.060]and a higher liver STQ value(HR=1.051,95%CI:1.009-1.095,P=0.018)were associated with an increased mortality risk after TIPS.No significant correlation was found between liver or spleen stiffness and overt hepatic encephalopathy post-TIPS.The liver STQ value[area under the receiver operating characteristic curve(AUC)=0.724(95%CI:0.563-0.884)]showed superior predictive performance compared to the Child-Pugh score[AUC=0.699(95%CI:0.529-0.870)]and was comparable to the model for end-stage liver disease score[AUC=0.746(95%CI:0.591-0.902)].CONCLUSION Following TIPS,spleen stiffness exhibited a more pronounced change than liver stiffness and was positively associated with PPG.Preoperative liver stiffness serves as a prognostic indicator for survival in patients undergoing TIPS. 展开更多
关键词 Liver and spleen stiffness Sound touch quantify Portal pressure gradient Transjugular intrahepatic portosystemic shunt PROGNOSIS
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Research on wear state prediction of ball end milling cutter based on entropy measurement of tool mark texture images
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作者 LI Mao-yue LU Xin-yuan +1 位作者 LIU Ze-long ZHANG Ming-lei 《Journal of Central South University》 2025年第1期174-188,共15页
Efficient tool condition monitoring techniques help to realize intelligent management of tool life and reduce tool usage costs.In this paper,the influence of different wear degrees of ball-end milling cutters on the t... Efficient tool condition monitoring techniques help to realize intelligent management of tool life and reduce tool usage costs.In this paper,the influence of different wear degrees of ball-end milling cutters on the texture shape of machining tool marks is investigated,and a method is proposed for predicting the wear state(including the position and degree of tool wear)of ball-end milling cutters based on entropy measurement of tool mark texture images.Firstly,data samples are prepared through wear experiments,and the change law of the tool mark texture shape with the tool wear state is analyzed.Then,a two-dimensional sample entropy algorithm is developed to quantify the texture morphology.Finally,the processing parameters and tool attitude are integrated into the prediction process to predict the wear value and wear position of the ball end milling cutter.After testing,the correlation between the predicted value and the standard value of the proposed tool condition monitoring method reaches 95.32%,and the accuracy reaches 82.73%,indicating that the proposed method meets the requirement of tool condition monitoring. 展开更多
关键词 ball-end cutter wear tool condition monitoring surface texture texture quantifier sample entropy
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Value of 3-dimensional speckle tracking imaging to quantify regional left ventricular function in patients with coronary artery disease
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作者 刘芳 《China Medical Abstracts(Internal Medicine)》 2013年第4期216-217,共2页
Objective To assess left ventricular (LV) strain by3-dimensional speckle tracking imaging (3D-STI) in patients with coronary heart disease (CHD) .Methods All subjects underwent invasive coronary angiography.2-dimensio... Objective To assess left ventricular (LV) strain by3-dimensional speckle tracking imaging (3D-STI) in patients with coronary heart disease (CHD) .Methods All subjects underwent invasive coronary angiography.2-dimensional and 3-dimensional echocardiography were performed in 52 subjects with suspected CHD.Longitudinal strain (LS) ,circumferential strain (CS) ,radial 展开更多
关键词 SPECKLE STENOSIS quantify SUSPECTED radial MODERATE BRANCHES initially enrolled negatively
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Reliability analysis of geotechnical infrastructures: Introduction 被引量:3
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作者 Wengang Zhang Anthony Teck Chee Goh 《Geoscience Frontiers》 SCIE CAS CSCD 2018年第6期1595-1596,共2页
In the design of geotechnical infrastructure,engineers have to deal with naturally occurring soils and rocks which are subjected to spatial variability as well as other uncertainties such as errors in measurement and ... In the design of geotechnical infrastructure,engineers have to deal with naturally occurring soils and rocks which are subjected to spatial variability as well as other uncertainties such as errors in measurement and in modeling methods.Reliability assessment which provides a systematic approach for quantifying the risk of failure has been shown to be a promising tool for solving these challenging geotechnical engineering problems.The method provides a more consistent measure of the level of safety or“structural reliability”through the evaluation of a reliability index and the associated“failure”probability,and is a method that satisfies the need to clearly convey safety issues to the public and regulatory authorities.Various methods for calculating the reliability of geotechnical infrastructures with regard to the assessment of the ultimate and serviceability limit states have been proposed by many researchers and these approaches include:the direct Monte Carlo Simulation,Bayesian and other sampling techniques,the first-order reliability method and the second-order reliability method,the random field method,the response surface method and other surrogate models with the related probabilistic procedures.In this special issue of Geoscience Frontiers,we assemble eleven invited papers which provide insights on the latest developments and challenges in applying probabilistic and reliability methods to geotechnical infrastructure design. 展开更多
关键词 GEOTECHNICAL INFRASTRUCTURE quantifying the risk of FAILURE
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Urinary metabonomics study of Wu-tou-tang and its co-decoction with Pinelliae Rhizoma in adjuvant-induced arthritis rats 被引量:6
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作者 Yao Qi Zi-Feng Pi +4 位作者 Shu Liu Feng-Rui Song Ying Xu Na Lin Zhi-Qiang Liu 《Chinese Chemical Letters》 SCIE CAS CSCD 2015年第3期387-392,共6页
Wu-tou-tang was applied to treat rheumatoid arthritis,rheumatic arthritis,and joint pain for thousands of years.Aconiti Radix Cocta is the primary component of Wu-tou-tang,and Aconiti Radix and Pinelliae Rhizoma is on... Wu-tou-tang was applied to treat rheumatoid arthritis,rheumatic arthritis,and joint pain for thousands of years.Aconiti Radix Cocta is the primary component of Wu-tou-tang,and Aconiti Radix and Pinelliae Rhizoma is one of the famous combination taboos in traditional Chinese medicine.A urinary metabonomics method based on the ultra-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry(UPLC-Q-TOF-MS) had been established to quantify the changes of the endogenous metabolites in the urine of adjuvant-induced arthritis rats treated by Wutou-tang and Wu-tou-tang and Pinelliae Rhizoma(WP) co-decoctions.There was a clear separation between Wu-tou-tang and WP co-decoction treated groups in the PCA model.16 potential biomarkers had been identified which correlated with how Pinelliae Rhizoma influenced the therapeutic effect made by Wu-tou-tang.Results showed that it could reduce the therapeutic effects or make some side effects when Pinelliae Rhizoma is added in Wu-tou-tang.This is the first time to use metabonomics to investigate the reason of combination taboo. 展开更多
关键词 decoction adjuvant Radix endogenous rheumatic urine metabolism taboo urinary quantify
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中英文化中量词对比研究(英文) 被引量:3
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作者 宋淑敏 《齐齐哈尔大学学报(哲学社会科学版)》 2006年第4期139-140,共2页
Chinese has special quantifiers as a part of speech while English does not have independent quantifiers.To some degree,the difference comes from the different cultural backgrounds.
关键词 CHINESE English quantifier DIFFERENCE CULTURE
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GERM CELL MUTATIONS IN MICE:STANDARDS FOR PROTECTING THE HUMAN GENOME 被引量:1
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作者 Udo H.Ehling 《癌变·畸变·突变》 CAS CSCD 1991年第S1期35-35,共1页
The most extensive set of information on the factorsaffecting mutation induction by chemical mutagens inmice has been obtained by use of the dominant lethalassay and the specific locus method.Dominant lethalmutations ... The most extensive set of information on the factorsaffecting mutation induction by chemical mutagens inmice has been obtained by use of the dominant lethalassay and the specific locus method.Dominant lethalmutations are caused by chromosomal aberrations,and they occur shortly before or after implantation. 展开更多
关键词 CHROMOSOMAL CELL implantation mutation LOCUS induction CATARACT INHERITED AFFECTING quantify
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Three methods for generating monotonic OWA operator weights with given orness level 被引量:1
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作者 刘新旺 《Journal of Southeast University(English Edition)》 EI CAS 2004年第3期369-373,共5页
Based on the properties of ordered weighted averaging (OWA) operator and regular increasing monotone (RIM) quantifier, three methods for generating monotonic OWA operator weights are proposed. They are geometric OWA o... Based on the properties of ordered weighted averaging (OWA) operator and regular increasing monotone (RIM) quantifier, three methods for generating monotonic OWA operator weights are proposed. They are geometric OWA operator weights, equidifferent OWA operator weights and the modified RIM quantifier OWA weights. Compared with most of the common OWA methods for generating weights, the methods proposed in this paper are more intuitive and efficient in computation. And as there are more than one solution in most cases, the decision maker can set some initial condition and chooses the appropriate solution in the real decision process, which increases the flexibility of decision making to some extent. All these three OWA methods for generating weights are illustrated by numerical examples. 展开更多
关键词 ordered weighted averaging operator orness measure fuzzy quantifier
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Modeling and Dynamic Analysis for the Foundation of a Blade-Rotor System 被引量:2
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作者 Liang Anyang Huang Guoyuan +1 位作者 Zhang Yuetong Yue Lin 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2017年第3期326-332,共7页
In order to achieve the model-based fault monitoring and diagnosis,an accurate model for the rotor system is necessary to locate and quantify faults.Since the dynamic characteristics of a blade-rotor system is influen... In order to achieve the model-based fault monitoring and diagnosis,an accurate model for the rotor system is necessary to locate and quantify faults.Since the dynamic characteristics of a blade-rotor system is influenced by foundation flexibility,the modeling and dynamic analyses on the foundation were sequentially investigated.Firstly,the effect of element size on the model convergence was investigated using the forward difference quotient as the slope of the frequency difference,which found that the model converged when the element size refined to 4mm.Secondly,a modal analysis and a harmonic response analysis were performed to obtain the dynamic characteristics of the foundation structure.Finally,an optimization to the foundation utilizing an additional stiffener was conducted to reduce the foundation response and make the critical speed far away from the working frequency band of 20—50Hz. 展开更多
关键词 rotor refined sequentially utilizing blade quantify quotient harmonic convergent locate
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EXPERIMENTAL STUDIES OF MEDICAL EQUIPMENT SELECTION USING THE MULTI-STAGE WEIGHTING EVALUTION METHOD 被引量:1
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作者 M.Zhang L.Zhang Department of Medical Engineering,Chinese PLA General Hospital,Beijing 100853,China 《Chinese Journal of Biomedical Engineering(English Edition)》 1993年第4期143-143,共1页
As more and more sophisticated medical equipment being purchased by hospi-tals,the selection is becoming an increasingly complex and important process.Usu-ally there are three steps in the selection process: planning,... As more and more sophisticated medical equipment being purchased by hospi-tals,the selection is becoming an increasingly complex and important process.Usu-ally there are three steps in the selection process: planning,feasibility and model se-lection evaluation.Model selection evalution is the most complex stage.The consid- 展开更多
关键词 sophisticated lection purchased MULTI STEPS weighting utilized simplify BECOMING quantify
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Computational analysis of spatiotemporal molecular hierarchy in single live cells
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作者 Shaoying Lu Jihye Seong +4 位作者 Yi Wang Shiou-chi Chang John Paul Eichorst Mingxing Ouyang Yingxiao Wang 《医用生物力学》 EI CAS CSCD 北大核心 2013年第S1期55-55,共1页
Genetically encoded biosensors based on fluorescence resonance energy transfer(FRET)have been widely applied to visualize the molecular activity in live cells with high spatiotemporal resolution.The enormous amount of... Genetically encoded biosensors based on fluorescence resonance energy transfer(FRET)have been widely applied to visualize the molecular activity in live cells with high spatiotemporal resolution.The enormous amount of video images and the complex dynamics of signaling events present tremendous challenges for data analysis and demand the development of intelligent and automated imaging analysis methods specifically envisioned for the studies of live cell imaging.We have developed a general correlative FRET imaging method(CFIM)to quantify the subcellular coupling between an enzymatic activity and a phenotypic response in live cells,e.g.at focal adhesions(FAs).CFIM quantitatively evaluated the cause-effect relation- 展开更多
关键词 visualize quantify FRET biosensors correlative INTELLIGENT quantitatively enormous AUTOMATED tremendous
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Spring constant regulate selectin-ligand bond dissociation
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作者 Yan Zhang Ganyun Sun +1 位作者 Shouqin L Mian Long 《医用生物力学》 EI CAS CSCD 北大核心 2013年第S1期95-96,共2页
Forced dissociation of selectin-ligand complex is crucial to such biological processes as leukocyte recruitment,thrombosis formation,as well as tumor metastasis<sup>[</sup>1].Although several assays and te... Forced dissociation of selectin-ligand complex is crucial to such biological processes as leukocyte recruitment,thrombosis formation,as well as tumor metastasis<sup>[</sup>1].Although several assays and techniques,e.g.,dynamic force spectroscopy(DFS),have been applied to probe the complex at single-bond level,the discrepancies in the loading rate dependence of bond rupture force were found in the assays,presumably due to the different pathways in energy landscape and binding kinetics of molecular complexes<sup>[2]</sup>.However,the underlying mechanisms remain unclear.Here an optical trap(OT)assay was used to quantify the bond rupture at r<sub>f</sub>≤20 pN/s 展开更多
关键词 SELECTIN DISSOCIATION RUPTURE kinetics landscape metastasis REGULATE quantify LEUKOCYTE unclear
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Effect of temperature on mudstone disintegration process revealed with image analysis
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作者 YAN Luo-bin Srdjan PETROVIC +3 位作者 HUANG Cheng XIE Chun-xia ZONG Hui-ming Milica KASANIN-GRUBIN 《Journal of Mountain Science》 SCIE CSCD 2022年第7期2126-2135,共10页
Quantifying rock weathering processes,especially in ways of nondisturbance and on-site investigation,is one of the most critical tasks in predicting rocks erosion rates and understanding the sediment transportation.We... Quantifying rock weathering processes,especially in ways of nondisturbance and on-site investigation,is one of the most critical tasks in predicting rocks erosion rates and understanding the sediment transportation.We proposed a more reproducible approach to test how image analysis can quantify the changes in the size and shape of fragments during the weathering process.Four artificial models were designed to select suitable metrics among over 20 parameters.To validate the efficiency of image analysis,we analyzed rocks from badlands in Nanxiong Basin,Southeast China,under three different ranges of temperature differences(TD)during cyclic wetting and drying(WD).Our results show that TDs can accelerate the disintegration rate,and even if there is only a 20℃ difference in the range of TDs,an apparent difference in fragment size was observed.Moreover,the shape of fragments became more round as the increasing number of cyclic treatments,and for samples that went through the same number of treatments,the larger the temperature difference,the more round the shape became.All that serves as another evidence for landscape evolution response to climatic warming. 展开更多
关键词 Mechanical weathering Temperature effect quantifying weathering rates Fragment size Fragment shape
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The Prediction of Population of the Yangtze Finless Porpoise
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作者 Yiheng LIU 《Agricultural Science & Technology》 CAS 2015年第7期1472-1476,共5页
[Objective] The aim was to study the current living situation of Yangtze finless porpoise, and explore the prediction of the number of Yangtze finless porpoise in next few years. [Method] Modified Leslie Model and Sil... [Objective] The aim was to study the current living situation of Yangtze finless porpoise, and explore the prediction of the number of Yangtze finless porpoise in next few years. [Method] Modified Leslie Model and Siler's Model was applied to estimate the number of Yangtze finless porpoise. [Result] Using the model,Yangtze finless porpoise will extinct in nearly 20 years. [Conclusion] The study provides a cautionary warning of the conservation of the freshwater cetacean species. 展开更多
关键词 Leslie Model Siler's Model Mortality rate quantify human activity
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