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Preliminary study on a quantification method and standardization for aquatic microbial loads based on microbial diversity absolute quantitative sequencing
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作者 Wen Li Jing Libin +4 位作者 Li Xiawei Lu Jing Jin Haowei Yang Yongqi Li Xueling 《China Standardization》 2026年第1期68-73,共6页
This study establishes and validates a method for the precise quantification of aquatic microbial loads using microbial diversity absolute quantitative sequencing.By adding synthetic spike-in DNA to water samples from... This study establishes and validates a method for the precise quantification of aquatic microbial loads using microbial diversity absolute quantitative sequencing.By adding synthetic spike-in DNA to water samples from the Dahei River prior to DNA extraction and 16S rRNA gene sequencing,it generates standard curves to convert sequencing data into absolute microbial copy numbers.The method,which is proved highly accurate(R^(2)>0.99),reveals a clear contrast between the river sites:the upstream community has not only a significantly higher total microbial load but also a completely different makeup of species compared to the downstream site.This approach effectively overcomes the limitations of relative abundance analysis,providing a powerful tool for environmental monitoring,and proposes key steps for future standardization to ensure data comparability and integration. 展开更多
关键词 absolute quantification microbial load 16S rRNA sequencing spike-in STANDARDIZATION aquatic microbes
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Sequential search-based Latin hypercube sampling scheme for digital twin uncertainty quantification with application in EHA 被引量:1
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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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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 and reduction of uncertainty in aerodynamic performance of GAN-generated airfoil shapes using MC dropouts
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作者 Kazuo Yonekura Ryuto Aoki Katsuyuki Suzuki 《Theoretical & Applied Mechanics Letters》 2025年第4期372-377,共6页
Generative adversarial network(GAN)models are widely used in mechanical designs.The aim in the airfoil shape design is to obtain shapes that exhibits the required aerodynamic performance,and conditional GAN is used fo... Generative adversarial network(GAN)models are widely used in mechanical designs.The aim in the airfoil shape design is to obtain shapes that exhibits the required aerodynamic performance,and conditional GAN is used for that aim.However,the output of GAN contains uncertainties.Additionally,the uncertainties of labels have not been quantified.This paper proposes an uncertainty quantification method to estimate the uncertainty of labels using Monte Carlo dropout.In addition,an uncertainty reduction method is proposed based on imbalanced training.The proposed method was evaluated for the airfoil generation task.The results indicated that the uncertainty was appropriately quantified and successfully reduced. 展开更多
关键词 Uncertainty quantification GAN Airfoil shapegeneration
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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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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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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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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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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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A rapid tool for quantification of latent infection of wheat leaves by powdery mildew
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作者 Aolin Wang Ru Jiang +9 位作者 Meihui Zhang Hudie Shao Fei Xu Kouhan Liu Haifeng Gao Jieru Fan Wei Liu Xiaoping Hu Yilin Zhou Xiangming Xu 《Journal of Integrative Agriculture》 2025年第12期4690-4702,共13页
Wheat powdery mildew caused by Blumeria graminis f.sp.tritici(Bgt)is an important disease worldwide.Detection of latent infection of leaves by the pathogen in late autumn is valuable for estimating the inoculum potent... Wheat powdery mildew caused by Blumeria graminis f.sp.tritici(Bgt)is an important disease worldwide.Detection of latent infection of leaves by the pathogen in late autumn is valuable for estimating the inoculum potential to assess disease risks in the spring.We developed a new tool for rapid detection and quantification of latent infection of seedlings by the pathogen.The method was based on recombinase polymerase amplification(RPA)coupled with an end-point detection via lateral flow device(LFD).The limit of detection is 100 agμL^(-1)of Bgt DNA,without noticeable interference from either other common wheat pathogens or wheat material(Triticum aestivum).It was evaluated on wheat seedlings for this accuracy and sensitivity in detecting latent infection of Bgt.We further extended this RPALFD assay to estimate the level of latent infection by Bgt based on imaging analysis.There was a strong correlation between the image-based and real-time PCR assay estimates of Bgt DNA.The present results suggested that this new tool can provide rapid and accurate quantification of Bgt in latently infected leaves and can be further development as an on-site monitoring tool. 展开更多
关键词 Blumeria graminis f.sp.tritici(Bgt) recombinase polymerase amplification(RPA) lateral flow device(LFD) image-based quantification disease monitoring
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Statistical method for quantifying the strain localization process in Beishan granite under multi-creep triaxial compression based on distributed optical fiber sensing
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作者 Xiujun Zhang Peng-Zhi Pan Shuting Miao 《Journal of Rock Mechanics and Geotechnical Engineering》 2026年第1期398-415,共18页
To investigate the damage evolution caused by stress-driven and sub-critical crack propagation within the Beishan granite under multi-creep triaxial compressive conditions,the distributed optical fiber sensing and X-r... To investigate the damage evolution caused by stress-driven and sub-critical crack propagation within the Beishan granite under multi-creep triaxial compressive conditions,the distributed optical fiber sensing and X-ray computed tomography were combined to obtain the strain distribution over the sample surface and internal fractures of the samples.The Gini and skewness(G-S)coefficients were used to quantify strain localization during tests,where the Gini coefficient reflects the degree of clustering of elements with high strain values,i.e.,strain localization/delocalization.The strain localization-induced asymmetry of data distribution is quantified by the skewness coefficient.A precursor to granite failure is defined by the rapid and simultaneous increase of the G-S coefficients,which are calculated from strain increment,giving an earlier warning of failure by about 8%peak stress than those from absolute strain values.Moreover,the process of damage accumulation due to stress-driven crack propagation in Beishan granite is different at various confining pressures as the stress exceeds the crack initiation stress.Concretely,strain localization is continuous until brittle failure at higher confining pressure,while both strain localization and delocalization occur at lower confining pressure.Despite the different stress conditions,a similar statistical characteristic of strain localization during the creep stage is observed.The Gini coefficient increases,and the skewness coefficient decreases slightly as the creep stress is below 95%peak stress.When the accelerated strain localization begins,the Gini and skewness coefficients increase rapidly and simultaneously. 展开更多
关键词 Statistical method Multi-creep triaxial compression Strain localization quantification Distributed optical fiber sensing Precursor identification
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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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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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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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Real-Time PCR Technique and Its Application in Quantification of Plant Nucleic Acid Molecules 被引量:8
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作者 刘进元 《Acta Botanica Sinica》 CSCD 2003年第6期631-637,共7页
Real-time PCR is a closed DNA amplification system that skillfully integrates biochemical, photoelectric and computer techniques. Fluorescence data acquired once per cycle provides rapid absolute quantification of ini... Real-time PCR is a closed DNA amplification system that skillfully integrates biochemical, photoelectric and computer techniques. Fluorescence data acquired once per cycle provides rapid absolute quantification of initial template copy numbers as PCR products are generated. This technique significantly simplifies and accelerates the process of producing reproducible quantification of nucleic acid molecules. It not only is a sensitive, accurate and rapid quantitative method, but it also provides an easier way to calculate the absolute starting copy number of nucleic acid molecules to be tested. Together with molecular bio-techniques, like microarray, real-time PCR will play a very important role in many aspects of molecular life science such as functional gene analysis and disease molecular diagnostics. This review introduces the detailed principles and application of the real-time PCR technique, describes a recently developed system for exact quantification of AUX/IAA genes In Arabidopsis, and discusses the problems with the real-time PCR process. 展开更多
关键词 real-time PCR technique quantification of plant nucleic acid molecules gene expression molecular medicine
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规划设计学中的调查分析法14—数量化Ⅰ类(Quantification Theory Type Ⅰ) 被引量:2
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作者 章俊华 《中国园林》 2003年第9期47-50,共4页
回归及重回归分析和预测,被广泛地应用于各个行业中。但是,有些相当于回归分析中的说明变数,不是数量数据,而是非数量数据,例如:影响入园人数的因素有星期(平日、休日)、天气状况(晴天、阴天、雨雪天等)、季节(春、夏、秋、冬)等。这些... 回归及重回归分析和预测,被广泛地应用于各个行业中。但是,有些相当于回归分析中的说明变数,不是数量数据,而是非数量数据,例如:影响入园人数的因素有星期(平日、休日)、天气状况(晴天、阴天、雨雪天等)、季节(春、夏、秋、冬)等。这些因素因为不是“量”的数据,所以不能用回归或重回归等方法进行分析和预测,但这种情况在规划设计的调查中经常出现,所以数量化Ⅰ类,可以帮助人们进行与回归分析和预测相同的分析,这是十分有效的一种分析方法。 展开更多
关键词 风景园林 规划设计学 调查 数量化I类
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Advances in the study of uncertainty quantification of large-scale hydrological modeling system 被引量:22
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作者 SONG Xiaomeng ZHAN Chesheng +1 位作者 KONG Fanzhe XIA Jun 《Journal of Geographical Sciences》 SCIE CSCD 2011年第5期801-819,共19页
The regional hydrological system is extremely complex because it is affected not only by physical factors but also by human dimensions.And the hydrological models play a very important role in simulating the complex s... The regional hydrological system is extremely complex because it is affected not only by physical factors but also by human dimensions.And the hydrological models play a very important role in simulating the complex system.However,there have not been effective methods for the model reliability and uncertainty analysis due to its complexity and difficulty.The uncertainties in hydrological modeling come from four important aspects:uncertainties in input data and parameters,uncertainties in model structure,uncertainties in analysis method and the initial and boundary conditions.This paper systematically reviewed the recent advances in the study of the uncertainty analysis approaches in the large-scale complex hydrological model on the basis of uncertainty sources.Also,the shortcomings and insufficiencies in the uncertainty analysis for complex hydrological models are pointed out.And then a new uncertainty quantification platform PSUADE and its uncertainty quantification methods were introduced,which will be a powerful tool and platform for uncertainty analysis of large-scale complex hydrological models.Finally,some future perspectives on uncertainty quantification are put forward. 展开更多
关键词 uncertainty quantification hydrological model PSUADE land-atmosphere coupling model large scale
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Evaluation of real-time RT-PCR assays for detection and quantification of norovirus genogroups Ⅰ and Ⅱ 被引量:9
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作者 Kitwadee Rupprom Porntip Chavalitshewinkoon-Petmitr +1 位作者 Pornphan Diraphat Leera Kittigul 《Virologica Sinica》 SCIE CAS CSCD 2017年第2期139-146,共8页
Noroviruses are the leading cause of acute gastroenteritis in humans. Real-time reverse transcription-polymerase chain reaction(real-time RT-PCR) is a promising molecular method for the detection of noroviruses. In th... Noroviruses are the leading cause of acute gastroenteritis in humans. Real-time reverse transcription-polymerase chain reaction(real-time RT-PCR) is a promising molecular method for the detection of noroviruses. In this study, the performance of three Taq Man real-time RT-PCR assays was assessed, which were one commercially available real-time RT-PCR kit(assay A:Norovirus Real Time RT-PCR kit) and two in-house real-time RT-PCR assays(assay B: Light Cycler RNA Master Hybprobe and assay C: Real Time ready RNA Virus Master). Assays A and B showed higher sensitivity than assay C for norovirus GI, while they all had the same sensitivity(103 DNA copies/m L) for GII DNA standard controls. Assay B had the highest efficiency for both genogroups.No cross-reactivity was observed among GI and GII noroviruses, rotavirus, hepatitis A virus, and poliovirus. The detection rates of these assays in GI and GII norovirus-positive fecal samples were not significantly different. However, the mean quantification cycle(Cq) value of assay B for GII was lower than assays A and C with statistical significance(P-value, 0.000). All three real-time RT-PCR assays could detect a variety of noroviruses including GI.2, GII.2, GII.3, GII.4, GII.6, GII.12, GII.17,and GII.21. This study suggests assay B as a suitable assay for the detection and quantification of noroviruses GI and GII due to good analytical sensitivity and higher performance to amplify norovirus on DNA standard controls and clinical samples. 展开更多
关键词 NOROVIRUS GENOGROUP real-time RT-PCR quantification
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