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A Gel-Free Budget-Friendly Approach to GFP-Tagged Viruses Quantification in Plant Samples
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作者 Rohith Grandhi Mélodie B.Plourde +1 位作者 Aditi Balasubramani Hugo Germain 《Phyton-International Journal of Experimental Botany》 2025年第5期1497-1504,共8页
Viral diseases are an important threat to crop yield,as they are responsible for losses greater than US$30 billion annually.Thus,understanding the dynamics of virus propagation within plant cells is essential for devi... Viral diseases are an important threat to crop yield,as they are responsible for losses greater than US$30 billion annually.Thus,understanding the dynamics of virus propagation within plant cells is essential for devising effective control strategies.However,viruses are complex to propagate and quantify.Existing methodologies for viral quantification tend to be expensive and time-consuming.Here,we present a rapid cost-effective approach to quantify viral propagation using an engineered virus expressing a fluorescent reporter.Using a microplate reader,we measured viral protein levels and we validated our findings through comparison by western blot analysis of viral coat protein,the most common approach to quantify viral titer.Our proposed methodology provides a practical and accessible approach to studying virus-host interactions and could contribute to enhancing our understanding of plant virology. 展开更多
关键词 Microplate reader CP-PlAMV viruses plant viral quantification green fluorescent protein western blot quantification Nicotiana benthamiana Arabidopsis thaliana Pearson’s correlation
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Quantification of Streptococcus salivarius using the digital polymerase chain reaction as a liver fibrosis marker
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作者 Shuichiro Iwasaki Akira Také +8 位作者 Haruki Uojima Kazue Horio Yoshihiko Sakaguchi Kazuyoshi Gotoh Takashi Satoh Hisashi Hidaka Yasuhito Tanaka Shunji Hayashi Chika Kusano 《World Journal of Hepatology》 2025年第4期53-66,共14页
BACKGROUND The Streptococcus salivarius(S.salivarius)group,which produces the enzyme urease has been identified as a potential contributor to ammonia production in the gut.Researchers have reported that patients with ... BACKGROUND The Streptococcus salivarius(S.salivarius)group,which produces the enzyme urease has been identified as a potential contributor to ammonia production in the gut.Researchers have reported that patients with minimal HE had an increased abundance of the S.salivarius group,which is a specific change in the gut microbiota that distinguishes them from healthy individuals.The correlation between the aggregation of specific bacterial species and fibrosis progression in chronic liver disease(CLD)is yet to be fully elucidated.AIM To quantify S.salivarius using digital PCR(dPCR)as a liver fibrosis marker of CLD.METHODS This study retrospectively analysed 52 patients with CLD.To quantify S.salivarius in patients with CLD using dPCR,we evaluated the specificity and sensitivity of S.salivarius bacterial load using dPCR for a type strain.Next,we evaluated the clinical usefulness of dPCR for S.salivarius load quantification for detecting liver fibrosis in patients with CLD.The liver fibrosis stage was categorized into mild and advanced fibrosis based on pathological findings.RESULTS The dPCR assay revealed that S.salivarius was highly positive for the tnpA gene.The lower limit of quantification for dPCR using the tnpA gene with a 1μL template comprising 1.28×102 CFU/mL was 4.3 copies.After considering the detection range in dPCR,we adjusted the extracted DNA concentration to 5.0×10-4 ng/μL from 200 mg stool samples.The median bacterial loads of S.salivarius in stool sample from patients with mild and advanced fibrosis were 1.9 and 7.4 copies/μL,respectively.The quantification of S.salivarius load was observed more frequently in patients with advanced fibrosis than in those with mild fibrosis(P=0.032).CONCLUSION Quantifying of S.salivarius load using digital PCR is a useful biomarker for liver fibrosis in patients with CLD. 展开更多
关键词 Chronic liver disease Streptococcus salivarius Digital PCR Liver fibrosis Liver cirrhosis quantification
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Uncertainty Quantification of Dynamic Stall Aerodynamics for Large Mach Number Flow around Pitching Airfoils
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作者 Yizhe Han Guangjing Huang +2 位作者 Fei Xiao Zhiyin Huang Yuting Dai 《Fluid Dynamics & Materials Processing》 2025年第7期1657-1671,共15页
During high-speed forward flight,helicopter rotor blades operate across a wide range of Reynolds and Mach numbers.Under such conditions,their aerodynamic performance is significantly influenced by dynamic stall—a com... During high-speed forward flight,helicopter rotor blades operate across a wide range of Reynolds and Mach numbers.Under such conditions,their aerodynamic performance is significantly influenced by dynamic stall—a complex,unsteady flow phenomenon highly sensitive to inlet conditions such asMach and Reynolds numbers.The key features of three-dimensional blade stall can be effectively represented by the dynamic stall behavior of a pitching airfoil.In this study,we conduct an uncertainty quantification analysis of dynamic stall aerodynamics in high-Mach-number flows over pitching airfoils,accounting for uncertainties in inlet parameters.A computational fluid dynamics(CFD)model based on the compressible unsteady Reynolds-averagedNavier–Stokes(URANS)equations,coupledwith sliding mesh techniques,is developed to simulate the unsteady aerodynamic behavior and associated flow fields.To efficiently capture the aerodynamic responses while maintaining high accuracy,a multi-fidelity Co-Kriging surrogate model is constructed.This model integrates the precision of high-fidelity wind tunnel experiments with the computational efficiency of lower-fidelity URANS simulations.Its accuracy is validated through direct comparison with experimental data.Building upon this surrogate model,we employ interval analysis and the Sobol sensitivity method to quantify the uncertainty and parameter sensitivity of the unsteady aerodynamic forces resulting frominlet condition variability.Both the inlet Mach number and Reynolds number are treated as uncertain inputs,modeled using interval representations.Our results demonstrate that variations inMach number contribute far more significantly to aerodynamic uncertainty than those in Reynolds number.Moreover,the presence of dynamic stall vortices markedly amplifies the aerodynamic sensitivity to Mach number fluctuations. 展开更多
关键词 Dynamic stall uncertainty quantification multi-fidelity surrogate modeling sensitivity analysis
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Fe^(3+) ion quantification with reusable bioinspired nanopores
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作者 Yanqiong Wang Yaqi Hou +1 位作者 Fengwei Huo Xu Hou 《Chinese Chemical Letters》 2025年第2期179-184,共6页
Excessive Fe^(3+) ion concentrations in wastewater pose a long-standing threat to human health.Achieving low-cost,high-efficiency quantification of Fe^(3+) ion concentration in unknown solutions can guide environmenta... Excessive Fe^(3+) ion concentrations in wastewater pose a long-standing threat to human health.Achieving low-cost,high-efficiency quantification of Fe^(3+) ion concentration in unknown solutions can guide environmental management decisions and optimize water treatment processes.In this study,by leveraging the rapid,real-time detection capabilities of nanopores and the specific chemical binding affinity of tannic acid to Fe^(3+),a linear relationship between the ion current and Fe^(3+) ion concentration was established.Utilizing this linear relationship,quantification of Fe^(3+) ion concentration in unknown solutions was achieved.Furthermore,ethylenediaminetetraacetic acid disodium salt was employed to displace Fe^(3+) from the nanopores,allowing them to be restored to their initial conditions and reused for Fe^(3+) ion quantification.The reusable bioinspired nanopores remain functional over 330 days of storage.This recycling capability and the long-term stability of the nanopores contribute to a significant reduction in costs.This study provides a strategy for the quantification of unknown Fe^(3+) concentration using nanopores,with potential applications in environmental assessment,health monitoring,and so forth. 展开更多
关键词 Bioinspired nanopores Fe^(3+)ion quantification Chemical binding affinity Tannic acid REUSABILITY
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Research on Quantification Mechanism of Data Source Reliability Based on Trust Evaluation
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作者 Gaoshang Lu Fa Fu Zixiang Tang 《Computers, Materials & Continua》 2025年第6期4239-4256,共18页
In the data transaction process within a data asset trading platform,quantifying the trustworthiness of data source nodes is challenging due to their numerous attributes and complex structures.To address this issue,a ... In the data transaction process within a data asset trading platform,quantifying the trustworthiness of data source nodes is challenging due to their numerous attributes and complex structures.To address this issue,a distributed data source trust assessment management framework,a trust quantification model,and a dynamic adjustment mechanism are proposed.Themodel integrates the Analytic Hierarchy Process(AHP)and Dempster-Shafer(D-S)evidence theory to determine attribute weights and calculate direct trust values,while the PageRank algorithm is employed to derive indirect trust values.Thedirect and indirect trust values are then combined to compute the comprehensive trust value of the data source.Furthermore,a dynamic adjustment mechanism is introduced to continuously update the comprehensive trust value based on historical assessment data.By leveraging the collaborative efforts of multiple nodes in the distributed network,the proposed framework enables a comprehensive,dynamic,and objective evaluation of data source trustworthiness.Extensive experimental analyses demonstrate that the trust quantification model effectively handles large-scale data source trust assessments,exhibiting both strong trust differentiation capability and high robustness. 展开更多
关键词 Trust evaluation data source reliability distributed network quantification mechanism
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Sequential search-based Latin hypercube sampling scheme for digital twin uncertainty quantification with application in EHA
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作者 Dong LIU Shaoping WANG +1 位作者 Jian SHI Di LIU 《Chinese Journal of Aeronautics》 2025年第4期176-192,共17页
For uncertainty quantification of complex models with high-dimensional,nonlinear,multi-component coupling like digital twins,traditional statistical sampling methods,such as random sampling and Latin hypercube samplin... For uncertainty quantification of complex models with high-dimensional,nonlinear,multi-component coupling like digital twins,traditional statistical sampling methods,such as random sampling and Latin hypercube sampling,require a large number of samples,which entails huge computational costs.Therefore,how to construct a small-size sample space has been a hot issue of interest for researchers.To this end,this paper proposes a sequential search-based Latin hypercube sampling scheme to generate efficient and accurate samples for uncertainty quantification.First,the sampling range of the samples is formed by carving the polymorphic uncertainty based on theoretical analysis.Then,the optimal Latin hypercube design is selected using the Latin hypercube sampling method combined with the"space filling"criterion.Finally,the sample selection function is established,and the next most informative sample is optimally selected to obtain the sequential test sample.Compared with the classical sampling method,the generated samples can retain more information on the basis of sparsity.A series of numerical experiments are conducted to demonstrate the superiority of the proposed sequential search-based Latin hypercube sampling scheme,which is a way to provide reliable uncertainty quantification results with small sample sizes. 展开更多
关键词 Digital Twin(DT) Genetic algorithms(GA) Optimal Latin Hypercube Design(Opt LHD) Sequential test Uncertainty quantification(UQ) EHA
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MultiJSQ:Direct joint segmentation and quantification of left ventricle with deep multitask-derived regression network
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作者 Xiuquan Du Zheng Pei +3 位作者 Ying Liu Xinzhi Cao Lei Li Shuo Li 《CAAI Transactions on Intelligence Technology》 2025年第1期175-192,共18页
Quantitative analysis of clinical function parameters from MRI images is crucial for diagnosing and assessing cardiovascular disease.However,the manual calculation of these parameters is challenging due to the high va... Quantitative analysis of clinical function parameters from MRI images is crucial for diagnosing and assessing cardiovascular disease.However,the manual calculation of these parameters is challenging due to the high variability among patients and the time-consuming nature of the process.In this study,the authors introduce a framework named MultiJSQ,comprising the feature presentation network(FRN)and the indicator prediction network(IEN),which is designed for simultaneous joint segmentation and quantification.The FRN is tailored for representing global image features,facilitating the direct acquisition of left ventricle(LV)contour images through pixel classification.Additionally,the IEN incorporates specifically designed modules to extract relevant clinical indices.The authors’method considers the interdependence of different tasks,demonstrating the validity of these relationships and yielding favourable results.Through extensive experiments on cardiac MR images from 145 patients,MultiJSQ achieves impressive outcomes,with low mean absolute errors of 124 mm^(2),1.72 mm,and 1.21 mm for areas,dimensions,and regional wall thicknesses,respectively,along with a Dice metric score of 0.908.The experimental findings underscore the excellent performance of our framework in LV segmentation and quantification,highlighting its promising clinical application prospects. 展开更多
关键词 global image features joint segmentation and quantification left ventricle(LV) multitask-derived regression network
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High-dimensional uncertainty quantification of projectile motion in the barrel of a truck-mounted howitzer based on probability density evolution method 被引量:1
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作者 Mingming Wang Linfang Qian +3 位作者 Guangsong Chen Tong Lin Junfei Shi Shijie Zhou 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第2期209-221,共13页
This paper proposed an efficient research method for high-dimensional uncertainty quantification of projectile motion in the barrel of a truck-mounted howitzer.Firstly,the dynamic model of projectile motion is establi... This paper proposed an efficient research method for high-dimensional uncertainty quantification of projectile motion in the barrel of a truck-mounted howitzer.Firstly,the dynamic model of projectile motion is established considering the flexible deformation of the barrel and the interaction between the projectile and the barrel.Subsequently,the accuracy of the dynamic model is verified based on the external ballistic projectile attitude test platform.Furthermore,the probability density evolution method(PDEM)is developed to high-dimensional uncertainty quantification of projectile motion.The engineering example highlights the results of the proposed method are consistent with the results obtained by the Monte Carlo Simulation(MCS).Finally,the influence of parameter uncertainty on the projectile disturbance at muzzle under different working conditions is analyzed.The results show that the disturbance of the pitch angular,pitch angular velocity and pitch angular of velocity decreases with the increase of launching angle,and the random parameter ranges of both the projectile and coupling model have similar influence on the disturbance of projectile angular motion at muzzle. 展开更多
关键词 Truck-mounted howitzer Projectile motion Uncertainty quantification Probability density evolution method
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Uncertainty quantification of mechanism motion based on coupled mechanism—motor dynamic model for ammunition delivery system 被引量:1
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作者 Jinsong Tang Linfang Qian +3 位作者 Longmiao Chen Guangsong Chen Mingming Wang Guangzu Zhou 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第3期125-133,共9页
In this paper,a dynamic modeling method of motor driven electromechanical system is presented,and the uncertainty quantification of mechanism motion is investigated based on this method.The main contribution is to pro... In this paper,a dynamic modeling method of motor driven electromechanical system is presented,and the uncertainty quantification of mechanism motion is investigated based on this method.The main contribution is to propose a novel mechanism-motor coupling dynamic modeling method,in which the relationship between mechanism motion and motor rotation is established according to the geometric coordination of the system.The advantages of this include establishing intuitive coupling between the mechanism and motor,facilitating the discussion for the influence of both mechanical and electrical parameters on the mechanism,and enabling dynamic simulation with controller to take the randomness of the electric load into account.Dynamic simulation considering feedback control of ammunition delivery system is carried out,and the feasibility of the model is verified experimentally.Based on probability density evolution theory,we comprehensively discuss the effects of system parameters on mechanism motion from the perspective of uncertainty quantization.Our work can not only provide guidance for engineering design of ammunition delivery mechanism,but also provide theoretical support for modeling and uncertainty quantification research of mechatronics system. 展开更多
关键词 Ammunition delivery system Electromechanical coupling dynamics Uncertainty quantification Generalized probability density evolution
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Quantification of the concrete freeze-thaw environment across the Qinghai–Tibet Plateau based on machine learning algorithms
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作者 QIN Yanhui MA Haoyuan +3 位作者 ZHANG Lele YIN Jinshuai ZHENG Xionghui LI Shuo 《Journal of Mountain Science》 SCIE CSCD 2024年第1期322-334,共13页
The reasonable quantification of the concrete freezing environment on the Qinghai-Tibet Plateau(QTP)is the primary issue in frost resistant concrete design,which is one of the challenges that the QTP engineering manag... The reasonable quantification of the concrete freezing environment on the Qinghai-Tibet Plateau(QTP)is the primary issue in frost resistant concrete design,which is one of the challenges that the QTP engineering managers should take into account.In this paper,we propose a more realistic method to calculate the number of concrete freeze-thaw cycles(NFTCs)on the QTP.The calculated results show that the NFTCs increase as the altitude of the meteorological station increases with the average NFTCs being 208.7.Four machine learning methods,i.e.,the random forest(RF)model,generalized boosting method(GBM),generalized linear model(GLM),and generalized additive model(GAM),are used to fit the NFTCs.The root mean square error(RMSE)values of the RF,GBM,GLM,and GAM are 32.3,4.3,247.9,and 161.3,respectively.The R^(2)values of the RF,GBM,GLM,and GAM are 0.93,0.99,0.48,and 0.66,respectively.The GBM method performs the best compared to the other three methods,which was shown by the results of RMSE and R^(2)values.The quantitative results from the GBM method indicate that the lowest,medium,and highest NFTC values are distributed in the northern,central,and southern parts of the QTP,respectively.The annual NFTCs in the QTP region are mainly concentrated at 160 and above,and the average NFTCs is 200 across the QTP.Our results can provide scientific guidance and a theoretical basis for the freezing resistance design of concrete in various projects on the QTP. 展开更多
关键词 Freeze-thaw cycles quantification Machine learning algorithms Qinghai-Tibet Plateau CONCRETE
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Investigation on mechanical properties regulation of rock-like specimens based on 3D printing and similarity quantification
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作者 Duanyang Zhuang Zexu Ning +3 位作者 Yunmin Chen Jinlong Li Qingdong Li Wenjie Xu 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2024年第5期573-585,共13页
3D printing is widely adopted to quickly produce rock mass models with complex structures in batches,improving the consistency and repeatability of physical modeling.It is necessary to regulate the mechanical properti... 3D printing is widely adopted to quickly produce rock mass models with complex structures in batches,improving the consistency and repeatability of physical modeling.It is necessary to regulate the mechanical properties of 3D-printed specimens to make them proportionally similar to natural rocks.This study investigates mechanical properties of 3D-printed rock analogues prepared by furan resin-bonded silica sand particles.The mechanical property regulation of 3D-printed specimens is realized through quantifying its similarity to sandstone,so that analogous deformation characteristics and failure mode are acquired.Considering similarity conversion,uniaxial compressive strength,cohesion and stress–strain relationship curve of 3D-printed specimen are similar to those of sandstone.In the study ranges,the strength of 3D-printed specimen is positively correlated with the additive content,negatively correlated with the sand particle size,and first increases then decreases with the increase of curing temperature.The regulation scheme with optimal similarity quantification index,that is the sand type of 70/140,additive content of 2.5‰and curing temperature of 81.6℃,is determined for preparing 3D-printed sandstone analogues and models.The effectiveness of mechanical property regulation is proved through uniaxial compression contrast tests.This study provides a reference for preparing rock-like specimens and engineering models using 3D printing technology. 展开更多
关键词 3D printing Mechanical property regulation Similarity quantification Rock analogue SANDSTONE
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Surrogate model uncertainty quantification for active learning reliability analysis
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作者 Yong PANG Shuai ZHANG +4 位作者 Pengwei LIANG Muchen WANG Zhuangzhuang GONG Xueguan SONG Ziyun KAN 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2024年第12期55-70,共16页
Surrogate models offer an efficient approach to tackle the computationally intensive evaluation of performance functions in reliability analysis.Nevertheless,the approximations inherent in surrogate models necessitate... Surrogate models offer an efficient approach to tackle the computationally intensive evaluation of performance functions in reliability analysis.Nevertheless,the approximations inherent in surrogate models necessitate the consideration of surrogate model uncertainty in estimating failure probabilities.This paper proposes a new reliability analysis method in which the uncertainty from the Kriging surrogate model is quantified simultaneously.This method treats surrogate model uncertainty as an independent entity,characterizing the estimation error of failure probabilities.Building upon the probabilistic classification function,a failure probability uncertainty is proposed by integrating the difference between the traditional indicator function and the probabilistic classification function to quantify the impact of surrogate model uncertainty on failure probability estimation.Furthermore,the proposed uncertainty quantification method is applied to a newly designed reliability analysis approach termed SUQ-MCS,incorporating a proposed median approximation function for active learning.The proposed failure probability uncertainty serves as the stopping criterion of this framework.Through benchmarking,the effectiveness of the proposed uncertainty quantification method is validated.The empirical results present the competitive performance of the SUQ-MCS method relative to alternative approaches. 展开更多
关键词 Reliability analysis Kriging model Uncertainty quantification Active learning Monte Carlo simulation
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Molecular quantification of herbs(Herb-Q):a pyrosequencingbased approach and its application in Pinellia ternata
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作者 PEI Yifei LIU Ziyi +5 位作者 YU Dade ZHANG Xiangyu SUN Wei CHEN Xiaofang FENG Xue LI Xiwen 《Chinese Journal of Natural Medicines》 SCIE CAS CSCD 2024年第7期663-672,共10页
Variations in herb dosage due to species adulteration and dosing inaccuracies can substantially affect clinical safety and efficacy.Accurate species quantification remains challenging,as current methods often yield in... Variations in herb dosage due to species adulteration and dosing inaccuracies can substantially affect clinical safety and efficacy.Accurate species quantification remains challenging,as current methods often yield inconsistent results.This study introduces a novel pyrosequencing-based technique,termed herb molecular quantification(Herb-Q),designed to precisely quantify herbal products.We evaluated its effectiveness using Pinellia ternata and five of its adulterants.Initially,we assessed commonly used DNA barcodes with sequences from a public database,identifying two candidate regions,Maturase K(matK)and internal transcribed spacer 2(ITS2),for screening specific single nucleotide polymorphism(SNP)loci,allowing for species-specific identification.These loci were validated by amplifying and sequencing genomic material from collected samples.Our validation studies showed that Herb-Q demonstrated excellent linearity,accuracy,repeatability,and detection limits.We established quantitative standard curves with high R^(2)values(>0.99)to enable precise species quantification,which were combined with external standards to provide clear and accurate visual quantification results.The average bias in quantifying the tuber of P.ternata was 2.38%,confirming that Herb-Q can accurately identify and quantify herbal product constituents.Moreover,the entire quantification process took less than 4 h.This study presents a novel,rapid method for accurately quantifying species in herbal products and advances the application of DNA barcoding from species identification to quantitative detection. 展开更多
关键词 quantification ADULTERANT DNA barcodes Single nucleotide polymorphism
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Revolutionizing disease diagnosis and management:Open-access magnetic resonance imaging datasets a challenge for artificial intelligence driven liver iron quantification
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作者 Jaber H Jaradat Abdulqadir J Nashwan 《World Journal of Clinical Cases》 SCIE 2024年第17期2921-2924,共4页
Artificial intelligence(AI),particularly machine learning(ML)and deep learning(DL)techniques,such as convolutional neural networks(CNNs),have emerged as transformative technologies with vast potential in healthcare.Bo... Artificial intelligence(AI),particularly machine learning(ML)and deep learning(DL)techniques,such as convolutional neural networks(CNNs),have emerged as transformative technologies with vast potential in healthcare.Body iron load is usually assessed using slightly invasive blood tests(serum ferritin,serum iron,and serum transferrin).Serum ferritin is widely used to assess body iron and drive medical management;however,it is an acute phase reactant protein offering wrong interpretation in the setting of inflammation and distressed patients.Magnetic resonance imaging is a non-invasive technique that can be used to assess liver iron.The ML and DL algorithms can be used to enhance the detection of minor changes.However,a lack of open-access datasets may delay the advancement of medical research in this field.In this letter,we highlight the importance of standardized datasets for advancing AI and CNNs in medical imaging.Despite the current limitations,embracing AI and CNNs holds promise in revolutionizing disease diagnosis and treatment. 展开更多
关键词 Liver diseases Magnetic resonance imaging Iron quantification Machine learning Deep learning
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Multi-Compartment SCFA Quantification in Human
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作者 Jérémy Monteiro Antoine Lefèvre +6 位作者 Diane Dufour-Rainfray Adeline Oury Gabrielle Chicheri Laurent Galineau Hélène Blasco Lydie Nadal-Desbarats Patrick Emond 《American Journal of Analytical Chemistry》 CAS 2024年第6期177-200,共24页
Short-chain fatty acids (SCFA) play an important role in human biochemistry. They originate primarily from the digestive system through carbohydrates microbial fermentation. Most SCFA produced in the colon are absorbe... Short-chain fatty acids (SCFA) play an important role in human biochemistry. They originate primarily from the digestive system through carbohydrates microbial fermentation. Most SCFA produced in the colon are absorbed by the intestinal wall and enter the bloodstream to be distributed throughout the body for multiple purposes. At the intestinal level, SCFA play a role in controlling fat storage and fatty acid metabolism. The effects of these beneficial compounds therefore concern overall health. They facilitate energy expenditure and are valuable allies in the fight against obesity and diabetes. SCFA are also involved in the regulation of the levels of several neurotransmitters such as GABA (γ-aminobutyric acid), glutamate, serotonin, dopamine, and norepinephrine. Their role is also highlighted in many inflammatory and neurodegenerative diseases such as Alzheimer’s disease (AD) or Parkinson’s disease (PD). To have a realistic picture of the distribution of SCFA in different biological compartments of the human body, we propose to study SCFA simultaneously in five human biological samples: feces, saliva, serum, cerebrospinal fluid (CSF), and urine, as well as in Dried Blood Spot (DBS). To evaluate their concentration and repeatability, we used 10 aliquots from pooled samples, analyzed by 3-nitrophenylhydrazine (3-NPH) derivation and liquid chromatography coupled with high sensitivity mass spectrometry (LC-QqQ-MS). We also evaluated the SCFA assay on Dried Blood Spot (DBS). In this work, we adapted the pre-analytical parts for each sample to be able to use a common calibration curve, thus facilitating multi-assay quantification studies and so being less time-consuming. Moreover, we proposed new daughter ions from the same neutral loss (43 Da) to quantify SCFAs, thus improving the sensitivity. In conclusion, our methodology, based on a unique calibration curve for all samples for each SCFA, is well-suited to quantified them in a clinical context. 展开更多
关键词 LC-MS 3-Nitrophenylhydrazine Short-Chain Fatty Acids Human Biological Samples quantification
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Simultaneous quantification of flavonol glycosides, terpene lactones, polyphenols and carboxylic acids in Ginkgo biloba leaf extract by UPLC-QTOF-MS^E based metabolomic approach 被引量:10
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作者 赵一懿 郭洪祝 +1 位作者 陈有根 傅欣彤 《Journal of Chinese Pharmaceutical Sciences》 CAS CSCD 2017年第11期789-804,共16页
Abstract: In the present study, we established an ultra performance liquid chromatography coupled with time-of-flight mass spectrometry (UPLC-QTOF-MSE) method to simultaneously quantify 33 components in Ginkgo bilo... Abstract: In the present study, we established an ultra performance liquid chromatography coupled with time-of-flight mass spectrometry (UPLC-QTOF-MSE) method to simultaneously quantify 33 components in Ginkgo biloba leaf extracts (GBEs), including 17 flavonol glycosides, five terpene trilactones (TTLs), four polyphenols and seven carboxylic acids. This optimized method was successfully applied to analyze the explicit compositions of GBE samples collected from different places. Furthermore, the data were processed through unsupervised principal component analysis (PCA) and supervised orthogonal partial least squared discrimination analysis (OPLS-DA) to evaluate the quality and compare the differences between the samples according to the contents of the 33 chemical constituents. Bilobalide, protocatechuic acid, shikimic acid, quinic acid, ginkgolide B, ginkgolide J, kaempferol-3-O-rutinoside, isorhamnetin-3-O-rutinoside, quercetin-3-O-ct-L-rhamnopyranocyl-2"-(6'"-p-coumaroyl)-β-D-glucoside and rutin were recognized as characteristic chemical markers that contributed most to control the quality of GBEs. Based on the fact that GBEs should be standardized with the characteristic components as quality control chemical markers, it is most important to maintain the quality of GBEs stable and reliable, and this method also provided a good strategy to further rectify and standardize the GBEs market. 展开更多
关键词 Ginkgo biloba L. leaf extract UPLC-QTOF-MS^E PCA Multi-components quantification Genuine flavonol glycoside
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运用Real-time quantification PCR方法建立副溶血性弧菌在即食虾中的生长预测模型 被引量:5
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作者 彭织云 王敬敬 +2 位作者 唐晓阳 潘迎捷 赵勇 《食品工业科技》 CAS CSCD 北大核心 2013年第8期108-110,共3页
运用Real-time quantification PCR(real-time qPCR)方法建立副溶血性弧菌在即食虾中生长预测模型。首先构建质粒标准品,梯度稀释后建立标准曲线,然后用Real-time qPCR方法检测虾中副溶血性弧菌的数量,最后建立37℃下即食虾中副溶血性... 运用Real-time quantification PCR(real-time qPCR)方法建立副溶血性弧菌在即食虾中生长预测模型。首先构建质粒标准品,梯度稀释后建立标准曲线,然后用Real-time qPCR方法检测虾中副溶血性弧菌的数量,最后建立37℃下即食虾中副溶血性弧菌生长预测模型,并与传统涂布计数方法进行比较。结果表明,Real-time qPCR方法和传统计数方法均可建立Gmopertz模型、Logistic模型和Richards模型,模型拟合的相关系数R2均在0.9以上。基于Real-timeqPCR方法省时省力、特异性好等优点,用Real-time qPCR方法建立微生物预测模型是未来预测微生物学领域的一种发展趋势。 展开更多
关键词 REAL-TIME quantification PCR 副溶血性弧菌 生长预测模型
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Quantification of seven phenylpropanoid compounds in Chinese Cinnamomi Cortex and Ramulus by HPLC 被引量:3
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作者 袁鹏飞 马雅静 +7 位作者 苏丹 尚明英 徐风 刘广学 Niloufar Iranmanesh 李兰芳 姜廷良 蔡少青 《Journal of Chinese Pharmaceutical Sciences》 CAS CSCD 2015年第9期591-599,共9页
In the present study, we developed and validated a high-performance liquid chromatography method for the simultaneous determination of seven phenylpropanoid compounds (2-hydroxyl cinnamaldehyde, coumarin, cinnamyl al... In the present study, we developed and validated a high-performance liquid chromatography method for the simultaneous determination of seven phenylpropanoid compounds (2-hydroxyl cinnamaldehyde, coumarin, cinnamyl alcohol, cinnamic acid, 2-methoxy cinnamic acid, cinnamaldehyde and 2-methoxy cinnamaldehyde) in Cinnamomi Cortex and Cinnamomi Ramulus. The levels of seven phenylpropanoid compounds in Cinnamomi Cortex and Cinnamomi Ramulus were compared using this method. A total of 48 samples (27 Cinnamomi Cortex and 21 Cinnamomi Ramulus) were purchased in China and analyzed. Quantities of seven phenylpropanoid compounds ranged from 17.5 to 61.6 mg/g in Cinnamomi Cortex and ranged from 9.91 to 23.4 mg/g in Ciunamomi Ramulus. The level of 2-methoxy cinnamic acid in the Cinnamomi Cortex samples was below the LOD, whereas it ranged from 0 to 0.119 mg/g in the Cinnamomi Ramulus samples. The (cinnamyl alcohol+cinnamic acid)/cinnamaldehyde ratios (R346) of Ciunamomi Cortex and Cinnamomi Ramulus ranged from 0.0121 to 0.0467 and 0.0598 to 0.182, respectively. This ratio could be used to discriminate Cinnamomi Cortex (〈0.05) and Cinnamomi Ramulus (〉0.05). The extraction rates (Dn) of seven compounds in boiling water were different, with the lowest dissolution for cinnamaldehyde (〈3%) and the highest for cinnamic acid (about 60%). 展开更多
关键词 quantification Phenylpropanoid compounds Cinnamomi Cortex Cinnamomi Ramulus High-performance liquid chromatography
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Quantification of eugenol and bancroftione in Caryophylli Fructus using high-performance liquid chromatography 被引量:1
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作者 刘淑娟 林宗涛 +1 位作者 王弘 陈世忠 《Journal of Chinese Pharmaceutical Sciences》 CAS 2010年第6期459-463,共5页
For the first time, we have utilized high-performance liquid chromatography (HPLC) to simultaneously quantify the eugenol and bancroffione in Caryophylli Fructus. The optimized parameters included: Inertsil ODS-4 c... For the first time, we have utilized high-performance liquid chromatography (HPLC) to simultaneously quantify the eugenol and bancroffione in Caryophylli Fructus. The optimized parameters included: Inertsil ODS-4 column (150 mm×4.6 mm, 5 μm); column temperature: 35 ℃; mobile phase: methanol water (65:35, v/v); flow rate: 1.0 mL/min; detection wavelength: 280 nm. Eugenol and bancroftione showed good linear relationships with peak areas within the range of (0.0998 0.8982) mg/mL (r = 0.9999) and (0.1474-1.3266) mg/mL (r = 0.9999), respectively. The average recoveries were 102.52% and 100.96% for eugenol and bancroftione, respectively. Our results showed that the established method is simple, rapid, and accurate with good reproducibility to evaluate the quality of Caryophylli Fructus. 展开更多
关键词 Caryophylli Fructus EUGENOL Bancroftione quantification HPLC
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Quantification of the active ingredient quercetin of “Guangdong Wang-bu-liu-xing” by high-performance liquid chromatography with UV detection 被引量:1
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作者 曾颂 韩秀奇 李书渊 《Journal of Chinese Pharmaceutical Sciences》 CAS CSCD 2013年第1期101-105,共5页
High-performance liquid chromatography with UV detection was used for the quantification of the flavonoid quercetin, the active compound found in "Guangdong Wang-bu-liu-xing". The method was developed and demonstrat... High-performance liquid chromatography with UV detection was used for the quantification of the flavonoid quercetin, the active compound found in "Guangdong Wang-bu-liu-xing". The method was developed and demonstrated to provide superior performance over other commonly documented methods. This HPLC assay achieved high specificity through the use of a reversed-phase C18 column eluted with a mobile phase of methanol-0.4% (v/v) phosphoric acid (50:50, v/v) over the course of 30 min. UV detection at 360 nm was used. This analytical method provided excellent precision and a mean recovery of 99%, demonstrated by repeated analysis of 11 sample groups. Because of its high performance and simplicity, this HPLC assay can be readily utilized as a practical method for the quality control of active compounds extracted from Guangdong Wang-bu-liu-xing. 展开更多
关键词 Guangdong Wang-bu-liu-xing quantification HPLC QUERCETIN
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