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
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
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
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
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
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.
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
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
Coal mining activity is often restricted by geologic structural conditions, so it is very important to know the distribution situation of mine structures in advance of mining. For this reason, traditional qualitative ...Coal mining activity is often restricted by geologic structural conditions, so it is very important to know the distribution situation of mine structures in advance of mining. For this reason, traditional qualitative procedure must give way to quantitative prediction method backed by mathematics theory and computer technology. This paper explores some relevant problems with the method, introducing a software, MSPS, used to predict automatically and quantitatively the relative complexities of geologic structures in different blocks of a coal mining area, with an application example employing the software to select the most suitable mining sites.展开更多
Objective To measure the quantities and apoptosis-related protein levels of B lymphocyte in the patients with immunorelated pancytopenia （IRP） and explore the action of B lymphocyte in the pathogenic mechanism of IR...Objective To measure the quantities and apoptosis-related protein levels of B lymphocyte in the patients with immunorelated pancytopenia （IRP） and explore the action of B lymphocyte in the pathogenic mechanism of IRP. Methods Quantifies of whole B lymphocytes and CD5^＋ B lymphocytes as well as the expressions of Fas and Bcl-2 in B lymphocytes in 35 patients with untreated IRP, 15 IRP patients in complete remission （CR）, and 10 normal controls were assayed by flow cytometry. The percentages of B lymphocyte and CD5^＋ B lymphocyte were significantly higher in untreated IRP patients than in CR IRP patients and normal controls （ P 〈 0. 05 ）, and there was no significant difference between the latter two groups （ P 〉 0. 05 ）. There was no significant difference of Fas expression in B lymphocyte among three groups （ P 〉 0. 05）. The expression of Bcl-2 in B lymphocyte was significantly higher in untreated patients than in CR patients or normal controls （ P 〈 0. 01 ）, and significantly higher in CR patients than in normal controls （ P 〈 0. 01 ）. The apoptosis. related index was significantly lower in untreated patients than in CR patients or normal controls （ P 〈 0. 05 ）, and signif. icantly lower in CR patients than in normal controls （ P 〈 0. 05 ）. The percentage of B lymphocyte was positively correlated with post-treated response time （ r = 0. 53, P 〈 0. 01 ）. Conclusion The production of auto-antibodies in IRP patients probably has some relationship with the abnormal quantifies of B lymphocyte and its subpopulations as well as with the inhibition of B lymphocyte apoptosis.展开更多
The individual difference and non-repeatability in acupuncture have not only restricted the devel- opment of acupuncture, but have also affected the specificity of acupoints. The present study used instruments to cont...The individual difference and non-repeatability in acupuncture have not only restricted the devel- opment of acupuncture, but have also affected the specificity of acupoints. The present study used instruments to control needle depth, lifting and thrusting frequency, and the duration of acupuncture. Effects of the quantified acupuncture were observed at Neiguan （PC6） with different stimulation parameters. A frequency of 1, 2, or 3 Hz and duration of 5, 60, or 180 seconds were used to observe cerebral blood flow and ratio of infarct volume recovery. Results showed that stimulation at Neiguan with a frequency of 1 Hz and long duration of 180 seconds or 2/3 Hz and long duration of 5/60 seconds significantly increased cerebral blood flow and decreased the ratio of infarct volume. In- teractions between frequency and duration play a critical role in quantified acupuncture therapy.展开更多
Objective:To evaluate the correlation of the quantifiable parameters of blood flow pattern derived with dynamic CT in solitary bronchogenic adenocarcinoma(SBA).Methods:46 patients with solitary bronchogenic adenocarci...Objective:To evaluate the correlation of the quantifiable parameters of blood flow pattern derived with dynamic CT in solitary bronchogenic adenocarcinoma(SBA).Methods:46 patients with solitary bronchogenic adenocarcinomas (SBA)(diameter≤4 cm)underwent multi-location dynamic contrast material-enhanced(nonionic contrast material was administrated via the antecubital vein at a rate of 4 mL/s by using an autoinjector 90 mL,4×5 mm or 4×2.5 mm scanning mode with stable table were performed)serial CT.Precontrast and postcontrast attenuation on every scan was recorded.Perfusion (PBA),peak height(PHBA),ratio of peak height of the SPN to that of the aorta(BA-to-A ratio)and mean transit time(MTT)were calculated.The correlation between peak height of the aorta(PHA)and parameters of the SBA(PHBA,BA-to-A ratio,PBA,and MTT)and those among parameters of the SBA were assessed by means of linear regression analysis.Regression equation among parameters of the SBA were obtain by means of stepwise regression.Results:The correlation between the SBA peak height(PHBA,36.78 HU±12.02)and the aortic peak height(PHA)was significant(r=0.506,P<0.0001).No significant cor- relation was found between the BA-to-Apeak height ratio(15.33%±4.55)and the aortic peak height(r=0.130,P=0.388> 0.05)as it was between the SBA perfusion(PBA,31.86 mL/min/100 g±9.74)and the aortic peak height(r=0.049,P=0.749 >0.05).The SBA perfusion correlated with the PHBA and the BA-to-A peak height ratio(r=0.394,P=0.007<0.05;r=0.407, P=0.005<0.05).The PHBA correlated positively with the BA-to-A peak height ratio(r=0.781,P<0.0001).Mean transit time was 14.84 s±5.52.PBA=18.500+0.872×BA-to-A ratio.BA-to-A ratio=4.467+0.295×PHBA.Conclusion:The linear correlation between the SBA perfusion and BA-to-Aratio and that between BA-to-Aratio and PHBA can be expressed by equation. It is possible to design a simpler scanning procedure of investigation of bronchogenic adenocarcinoma angiogenesis.展开更多
Prognostics and health management （PHM） is very important to guarantee the reliability and safety of aerospace systems, and sensing and test are the precondition of PHM. Integrating design for testability into early...Prognostics and health management （PHM） is very important to guarantee the reliability and safety of aerospace systems, and sensing and test are the precondition of PHM. Integrating design for testability into early design stage of system early design stage is deemed as a fundamental way to improve PHM performance, and testability model is the base of testability analysis and design. This paper discusses a hierarchical model-based approach to testability modeling and analysis for heading attitude system health management. Quantified directed graph, of which the nodes represent components and tests and the directed edges represent fault propagation paths, is used to describe fault-test dependency, and quantitative testability information is assigned to nodes and directed edges. The fault dependencies between nodes can be obtained by functional fault analysis methodology that captures the physical architecture and material flows such as energy, heat, data, and so on. By incorporating physics of failure models into component, the dynamic process of a failing or degrading component can be projected onto system behavior, i.e., system symptoms. Then, the analysis of extended failure modes, mechanisms and effects is utilized to construct fault evolution-test dependency. Using this integrated model, the designers and system analysts can assess the test suite＇s fault detectability, fault isolability and fault predictability. And heading attitude system application results show that the proposed model can support testability analysis and design for PHM very well.展开更多
In order to ensure the effective analysis and reconstruction of forests,it is key to ensure the quantitative description of their spatial structure.In this paper,a distance model for the optimal stand spatial structur...In order to ensure the effective analysis and reconstruction of forests,it is key to ensure the quantitative description of their spatial structure.In this paper,a distance model for the optimal stand spatial structure based on weighted Voronoi diagrams is proposed.In particular,we provide a novel methodological model for the comprehensive evaluation of the spatial structure of forest stands in natural mixed conifer-broadleaved forests and the formulation of management decision plans.The applicability of the rank evaluation and the optimal solution distance model are compared and assessed for different standard sample plots of natural mixed conifer-broadleaved forests.The effect of crown width on the spatial structure unit of the trees is observed to be higher than that of the diameter at breast height.Moreover,the influence of crown length is greater than that of tree height.There are nine possible spatial structure units determined by the weighted Voronoi diagram for the number of neighboring trees in the central tree,with an average intersection of neighboring crowns reaching 80%.The rank rating of natural forest sample plots is correlated with the optimal solution distance model,and their results are generally consistent for natural forests.However,the rank rating is not able to provide a quantitative assessment.The optimal solution distance model is observed to be more comprehensive than traditional methods for the evaluation of the spatial structure of forest stands.It can effectively reflect the trends in realistic stand spatial structure factors close to or far from the ideal structure point,and accurately assesses the forest spatial structure.The proposed optimal solution distance model improves the integrated evaluation of the spatial structure of forest stands and provides solid theoretical and technical support for sustainable forest management.展开更多
Objective： To evaluate the correlation between the quantifiable parameters of blood flow pattern derived with dynamic CT in malignant solitary pulmonary nodules and tumor size. Methods： Sixty-eight patients with mal...Objective： To evaluate the correlation between the quantifiable parameters of blood flow pattern derived with dynamic CT in malignant solitary pulmonary nodules and tumor size. Methods： Sixty-eight patients with malignant solitary pulmonary nodules （SPNs） （diameter 〈4 cm） underwent multi-location dynamic contrast material-enhanced （nonionic contrast material was administrated via the antecubitai vein at a rate of 4mL/s by using an autoinjector, 4×5 mm or 4×2.5 mm scanning mode with stable table were performed）. Precontrast and postcontrast attenuation on every scan was recorded. Blood flow （BF）, peak, height （PHSPN）, ratio of peak height of the SPN to that of the aorta （SPN-to-A ratio） and mean transit time （MTT） were calculated. The correlation between the quantifiable parameters of blood flow pattern derived with dynamic CT in malignant solitary pulmonary nodules and tumor size were assessed by means of linear regression analysis. Results： No significant correlations were found between the tumor size and each of the peak height （PHSPN） （35.79±10.76 Hu）, ratio of peak height of the SPN to that of the aorta （SPN-to-A ratio）, （14.27%±4.37） and blood flow （BF） （30.18 mL/min/100 g±9.58） （r=0.180, P=0.142〉0.05; r=0.205, P=0.093〉0.05; r=0.008, P=0.947〉0.05）. Conclusion： No significant correlations were found between the tumor size and each of the quantifiable parameters of blood flow pattern derived with dynamic CT in malignant solitary pulmonary nodules.展开更多
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
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
文摘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.
基金supported by the following:the National Natural Science Foundation of China(Nos.62405141 and 22479079)Natural Science Research Start-up Foundation of Recruiting Talents of Nanjing University of Posts and Telecommunications(No.NY222178).
文摘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.
基金Project(51975169)supported by the National Natural Science Foundation of ChinaProject(LH2022E085)supported by the Natural Science Foundation of Heilongjiang Province,China。
文摘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.
基金Supported by National Natural Science Foundation of China,No.82200650Shanxi Provincial Clinical Research Center for Interventional Medicine,No.202204010501004+3 种基金the Precision Interventional Diagnosis and Treatment Technology Innovation Base for Cirrhosis and Portal Hypertension,No.YDZJSX20231B010the Natural Science Foundation of Shanxi Province,No.20210302124282 and No.202203021212046the Shanxi Province Higher Education“Billion Project Science and Technology Guidance Project”,No.2C622024120the National Natural Science Foundation of China Supporting Fund,No.Y82200650.
文摘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.
文摘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.
文摘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.
文摘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.
基金funded by the Natural Science Foundation of China(Grants 41901005)financial support from China Scholarship Council[grant number CSC201806995083]supported by the Ministry of Education,Science and Technological Development,Republic of Serbia(Grant No.451-039/2021-14/200026,451-03-9/2021-14/200168 and 451-03-9/2021-14/200358)。
文摘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.
文摘Coal mining activity is often restricted by geologic structural conditions, so it is very important to know the distribution situation of mine structures in advance of mining. For this reason, traditional qualitative procedure must give way to quantitative prediction method backed by mathematics theory and computer technology. This paper explores some relevant problems with the method, introducing a software, MSPS, used to predict automatically and quantitatively the relative complexities of geologic structures in different blocks of a coal mining area, with an application example employing the software to select the most suitable mining sites.
文摘Objective To measure the quantities and apoptosis-related protein levels of B lymphocyte in the patients with immunorelated pancytopenia （IRP） and explore the action of B lymphocyte in the pathogenic mechanism of IRP. Methods Quantifies of whole B lymphocytes and CD5^＋ B lymphocytes as well as the expressions of Fas and Bcl-2 in B lymphocytes in 35 patients with untreated IRP, 15 IRP patients in complete remission （CR）, and 10 normal controls were assayed by flow cytometry. The percentages of B lymphocyte and CD5^＋ B lymphocyte were significantly higher in untreated IRP patients than in CR IRP patients and normal controls （ P 〈 0. 05 ）, and there was no significant difference between the latter two groups （ P 〉 0. 05 ）. There was no significant difference of Fas expression in B lymphocyte among three groups （ P 〉 0. 05）. The expression of Bcl-2 in B lymphocyte was significantly higher in untreated patients than in CR patients or normal controls （ P 〈 0. 01 ）, and significantly higher in CR patients than in normal controls （ P 〈 0. 01 ）. The apoptosis. related index was significantly lower in untreated patients than in CR patients or normal controls （ P 〈 0. 05 ）, and signif. icantly lower in CR patients than in normal controls （ P 〈 0. 05 ）. The percentage of B lymphocyte was positively correlated with post-treated response time （ r = 0. 53, P 〈 0. 01 ）. Conclusion The production of auto-antibodies in IRP patients probably has some relationship with the abnormal quantifies of B lymphocyte and its subpopulations as well as with the inhibition of B lymphocyte apoptosis.
基金funded by Development Plan(973 Plan) of National Critical and Basic Research,No.2012CB518505,2010CB530500,2006CB504504
文摘The individual difference and non-repeatability in acupuncture have not only restricted the devel- opment of acupuncture, but have also affected the specificity of acupoints. The present study used instruments to control needle depth, lifting and thrusting frequency, and the duration of acupuncture. Effects of the quantified acupuncture were observed at Neiguan （PC6） with different stimulation parameters. A frequency of 1, 2, or 3 Hz and duration of 5, 60, or 180 seconds were used to observe cerebral blood flow and ratio of infarct volume recovery. Results showed that stimulation at Neiguan with a frequency of 1 Hz and long duration of 180 seconds or 2/3 Hz and long duration of 5/60 seconds significantly increased cerebral blood flow and decreased the ratio of infarct volume. In- teractions between frequency and duration play a critical role in quantified acupuncture therapy.
文摘Objective:To evaluate the correlation of the quantifiable parameters of blood flow pattern derived with dynamic CT in solitary bronchogenic adenocarcinoma(SBA).Methods:46 patients with solitary bronchogenic adenocarcinomas (SBA)(diameter≤4 cm)underwent multi-location dynamic contrast material-enhanced(nonionic contrast material was administrated via the antecubital vein at a rate of 4 mL/s by using an autoinjector 90 mL,4×5 mm or 4×2.5 mm scanning mode with stable table were performed)serial CT.Precontrast and postcontrast attenuation on every scan was recorded.Perfusion (PBA),peak height(PHBA),ratio of peak height of the SPN to that of the aorta(BA-to-A ratio)and mean transit time(MTT)were calculated.The correlation between peak height of the aorta(PHA)and parameters of the SBA(PHBA,BA-to-A ratio,PBA,and MTT)and those among parameters of the SBA were assessed by means of linear regression analysis.Regression equation among parameters of the SBA were obtain by means of stepwise regression.Results:The correlation between the SBA peak height(PHBA,36.78 HU±12.02)and the aortic peak height(PHA)was significant(r=0.506,P<0.0001).No significant cor- relation was found between the BA-to-Apeak height ratio(15.33%±4.55)and the aortic peak height(r=0.130,P=0.388> 0.05)as it was between the SBA perfusion(PBA,31.86 mL/min/100 g±9.74)and the aortic peak height(r=0.049,P=0.749 >0.05).The SBA perfusion correlated with the PHBA and the BA-to-A peak height ratio(r=0.394,P=0.007<0.05;r=0.407, P=0.005<0.05).The PHBA correlated positively with the BA-to-A peak height ratio(r=0.781,P<0.0001).Mean transit time was 14.84 s±5.52.PBA=18.500+0.872×BA-to-A ratio.BA-to-A ratio=4.467+0.295×PHBA.Conclusion:The linear correlation between the SBA perfusion and BA-to-Aratio and that between BA-to-Aratio and PHBA can be expressed by equation. It is possible to design a simpler scanning procedure of investigation of bronchogenic adenocarcinoma angiogenesis.
基金supported by National Natural Science Foundation of China (No. 51175502)
文摘Prognostics and health management （PHM） is very important to guarantee the reliability and safety of aerospace systems, and sensing and test are the precondition of PHM. Integrating design for testability into early design stage of system early design stage is deemed as a fundamental way to improve PHM performance, and testability model is the base of testability analysis and design. This paper discusses a hierarchical model-based approach to testability modeling and analysis for heading attitude system health management. Quantified directed graph, of which the nodes represent components and tests and the directed edges represent fault propagation paths, is used to describe fault-test dependency, and quantitative testability information is assigned to nodes and directed edges. The fault dependencies between nodes can be obtained by functional fault analysis methodology that captures the physical architecture and material flows such as energy, heat, data, and so on. By incorporating physics of failure models into component, the dynamic process of a failing or degrading component can be projected onto system behavior, i.e., system symptoms. Then, the analysis of extended failure modes, mechanisms and effects is utilized to construct fault evolution-test dependency. Using this integrated model, the designers and system analysts can assess the test suite＇s fault detectability, fault isolability and fault predictability. And heading attitude system application results show that the proposed model can support testability analysis and design for PHM very well.
基金funded by National Key Research and development project(2022YFD2201001)。
文摘In order to ensure the effective analysis and reconstruction of forests,it is key to ensure the quantitative description of their spatial structure.In this paper,a distance model for the optimal stand spatial structure based on weighted Voronoi diagrams is proposed.In particular,we provide a novel methodological model for the comprehensive evaluation of the spatial structure of forest stands in natural mixed conifer-broadleaved forests and the formulation of management decision plans.The applicability of the rank evaluation and the optimal solution distance model are compared and assessed for different standard sample plots of natural mixed conifer-broadleaved forests.The effect of crown width on the spatial structure unit of the trees is observed to be higher than that of the diameter at breast height.Moreover,the influence of crown length is greater than that of tree height.There are nine possible spatial structure units determined by the weighted Voronoi diagram for the number of neighboring trees in the central tree,with an average intersection of neighboring crowns reaching 80%.The rank rating of natural forest sample plots is correlated with the optimal solution distance model,and their results are generally consistent for natural forests.However,the rank rating is not able to provide a quantitative assessment.The optimal solution distance model is observed to be more comprehensive than traditional methods for the evaluation of the spatial structure of forest stands.It can effectively reflect the trends in realistic stand spatial structure factors close to or far from the ideal structure point,and accurately assesses the forest spatial structure.The proposed optimal solution distance model improves the integrated evaluation of the spatial structure of forest stands and provides solid theoretical and technical support for sustainable forest management.
文摘Objective： To evaluate the correlation between the quantifiable parameters of blood flow pattern derived with dynamic CT in malignant solitary pulmonary nodules and tumor size. Methods： Sixty-eight patients with malignant solitary pulmonary nodules （SPNs） （diameter 〈4 cm） underwent multi-location dynamic contrast material-enhanced （nonionic contrast material was administrated via the antecubitai vein at a rate of 4mL/s by using an autoinjector, 4×5 mm or 4×2.5 mm scanning mode with stable table were performed）. Precontrast and postcontrast attenuation on every scan was recorded. Blood flow （BF）, peak, height （PHSPN）, ratio of peak height of the SPN to that of the aorta （SPN-to-A ratio） and mean transit time （MTT） were calculated. The correlation between the quantifiable parameters of blood flow pattern derived with dynamic CT in malignant solitary pulmonary nodules and tumor size were assessed by means of linear regression analysis. Results： No significant correlations were found between the tumor size and each of the peak height （PHSPN） （35.79±10.76 Hu）, ratio of peak height of the SPN to that of the aorta （SPN-to-A ratio）, （14.27%±4.37） and blood flow （BF） （30.18 mL/min/100 g±9.58） （r=0.180, P=0.142〉0.05; r=0.205, P=0.093〉0.05; r=0.008, P=0.947〉0.05）. Conclusion： No significant correlations were found between the tumor size and each of the quantifiable parameters of blood flow pattern derived with dynamic CT in malignant solitary pulmonary nodules.
基金supported by the National Basic Research Program of China (973 Program,Nos.2011CB505300,2011CB505305)
文摘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.
文摘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.
