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MITRE ATT&CK-Driven Threat Analysis for Edge-IoT Environment and a Quantitative Risk Scoring Model
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作者 Tae-hyeon Yun Moohong Min 《Computer Modeling in Engineering & Sciences》 2025年第11期2707-2731,共25页
The dynamic,heterogeneous nature of Edge computing in the Internet of Things(Edge-IoT)and Industrial IoT(IIoT)networks brings unique and evolving cybersecurity challenges.This study maps cyber threats in Edge-IoT/IIoT... The dynamic,heterogeneous nature of Edge computing in the Internet of Things(Edge-IoT)and Industrial IoT(IIoT)networks brings unique and evolving cybersecurity challenges.This study maps cyber threats in Edge-IoT/IIoT environments to the Adversarial Tactics,Techniques,and Common Knowledge(ATT&CK)framework by MITRE and introduces a lightweight,data-driven scoring model that enables rapid identification and prioritization of attacks.Inspired by the Factor Analysis of Information Risk model,our proposed scoring model integrates four key metrics:Common Vulnerability Scoring System(CVSS)-based severity scoring,Cyber Kill Chain–based difficulty estimation,Deep Neural Networks-driven detection scoring,and frequency analysis based on dataset prevalence.By aggregating these indicators,the model generates comprehensive risk profiles,facilitating actionable prioritization of threats.Robustness and stability of the scoring model are validated through non-parametric correlation analysis using Spearman’s and Kendall’s rank correlation coefficients,demonstrating consistent performance across diverse scenarios.The approach culminates in a prioritized attack ranking that provides actionable guidance for risk mitigation and resource allocation in Edge-IoT/IIoT security operations.By leveraging real-world data to align MITRE ATT&CK techniques with CVSS metrics,the framework offers a standardized and practically applicable solution for consistent threat assessment in operational settings.The proposed lightweight scoring model delivers rapid and reliable results under dynamic cyber conditions,facilitating timely identification of attack scenarios and prioritization of response strategies.Our systematic integration of established taxonomies with data-driven indicators strengthens practical risk management and supports strategic planning in next-generation IoT deployments.Ultimately,this work advances adaptive threat modeling for Edge/IIoT ecosystems and establishes a robust foundation for evidence-based prioritization in emerging cyber-physical infrastructures. 展开更多
关键词 MITRE ATT&CK edge environment IOT threat analysis quantitative analysis deep neural network CVSS risk assessment scoring model
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Cryptocurrency Volatility and Its Impact on Emerging Markets: Quantitative Analysis
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作者 Xinyang Kray Wang 《Economics World》 2025年第2期106-112,共7页
Cryptocurrency,a booming decentralised asset designed based on the blockchain architecture,is particularly important to the market at the present time by studying the volatility risk of cryptocurrencies.In this paper,... Cryptocurrency,a booming decentralised asset designed based on the blockchain architecture,is particularly important to the market at the present time by studying the volatility risk of cryptocurrencies.In this paper,we empirically analyse the volatility risk of cryptocurrencies through quantitative analysis models,comprehensively using the Markov state transition GARCH model with skewed distribution(Skew-MSGARCH)and the autoregressive conditional volatility density ARJI model introducing the Poisson jump factor,and selecting the earliest developed and the most mature currency price volatility daily return series,to deeply explore the volatility risk of digital cryptocurrencies.risk.Finally,it can be seen through in-depth analyses that the expectation factor and information inducement are the main reasons leading to the exacerbation of the volatility risk of digital cryptocurrencies.It is recommended that this situation be optimised and improved in terms of the value function of digital cryptocurrencies themselves and the implementation of systematic risk management and regulatory innovation.As an important component of the digital economy,blockchain technology can effectively regulate and improve the volatility of digital cryptocurrencies under macroeconomic policies,thereby maintaining the security and stability of emerging financial markets. 展开更多
关键词 cryptocurrency VOLATILITY emerging markets quantitative analysis
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Quantitative Analysis of the Policy of Centralized Drug Procurement Based on PMC Index Model
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作者 Duan Xiaoxiang Wang Shuling 《Asian Journal of Social Pharmacy》 2025年第3期222-235,共14页
Objective To quantitatively analyze the policy of centralized drug procurement centralized drug procurement in order to provide reference for the subsequent policy formulation and improvement.Methods Text mining metho... Objective To quantitatively analyze the policy of centralized drug procurement centralized drug procurement in order to provide reference for the subsequent policy formulation and improvement.Methods Text mining method was used to process 15 centralized drugs procurement policies issued at the national level during 2015-2022,and a PMC index evaluation model of centralized drug procurement policies was established.Then,15 centralized drug procurement policies were quantitatively analyzed from the overall and comparative perspective through an evaluation model.Results and Conclusion The average PMC index of 15 centralized drug procurement policies was 6.95,which was acceptable on the whole.Among them,eight were excellent and seven were acceptable.As to the first-order variables,the centralized drugs procurement policy still lacks incentives and constraints.The comparative results show that there are differences in the content and structure of policies,but they are strongly related to each other.Chinese centralized drug procurement policy has been basically formed,which is closely related to medical insurance and medical policies.However,it is still necessary to pay attention to the structure of the policy to ensure the elaboration of the policy content. 展开更多
关键词 centralized drug procurement PMC index POLICY quantitative analysis
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Ultra-simplified design and quantitative analysis for the optical system of compact laser-induced breakdown spectroscopy
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作者 Jiujiang YAN Ke LIU +3 位作者 Jinxiu MA Yang LI Kailong LI Hongwei WEI 《Plasma Science and Technology》 2025年第3期87-93,共7页
Optimization and simplification of optical systems represent a milestone in advancing the development of handheld and portable laser-induced breakdown spectroscopy(LIBS)systems towards smaller,more integrated forms.Th... Optimization and simplification of optical systems represent a milestone in advancing the development of handheld and portable laser-induced breakdown spectroscopy(LIBS)systems towards smaller,more integrated forms.This research,for the first time,conducted a comprehensive optimization design and comparative analysis of three compact LIBS system optical paths:the paraxial optical path(OP),the off-axis OP,and the reflective OP.The differences in spectral intensity and stability among these paths were revealed,providing a scientific basis for selecting the optimal OP for LIBS systems.The research found that the paraxial OP excels in spectral performance and quantitative analysis accuracy,making it the preferred choice for compact LIBS systems.Specifically,the paraxial OP significantly enhances spectral intensity,achieving a 6 times improvement over the off-axis OP and an even more remarkable 150 times increase compared to the reflective OP,greatly enhancing detection sensitivity.Additionally,the relative standard deviation,spectral stability index,maintains a consistently low level,ranging from 10.9%to 13.4%,significantly outperforming the other two OPs and ensuring the reliability of analytical results.In the field of quantitative analysis,the paraxial OP also demonstrates higher accuracy,precision,and sensitivity,comparing to other OPs.The quantitative analysis models for Si,Cu,and Ti elements exhibit excellent fitting,providing users with high-quality quantitative analysis results that are of great significance for applications in material science,environmental monitoring,industrial inspection,and other fields.In summary,this study not only confirms the enormous application potential of the paraxial OP in compact LIBS systems but also provides valuable practical experience and theoretical support for the miniaturization and integration of LIBS systems.Looking ahead,with continuous technological advancements,the design of the paraxial OP is expected to further propel the widespread adoption of LIBS technology in portable,on-site detection applications. 展开更多
关键词 compact LIBS optical path design spectral stability quantitative analysis
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High-precision quantitative analysis of 3-nitro-1,2,4-triazol-5-one(NTO)concentration based on ATR-FTIR spectroscopy and machine learning
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作者 Zhe Zhang Zhuowei Sun +4 位作者 Haoming Zou Xijuan Lv Ziyang Guo Shuai Zhao Qinghai Shu 《Defence Technology(防务技术)》 2025年第10期131-141,共11页
3-Nitro-1,2,4-triazol-5-one(NTO)is a typical high-energy,low-sensitivity explosive,and accurate concentration monitoring is critical for crystallization process control.In this study,a high-precision quantitative anal... 3-Nitro-1,2,4-triazol-5-one(NTO)is a typical high-energy,low-sensitivity explosive,and accurate concentration monitoring is critical for crystallization process control.In this study,a high-precision quantitative analytical model for NTO concentration in ethanol solutions was developed by integrating real-time ATR-FTIR spectroscopy with chemometric and machine learning techniques.Dynamic spectral data were obtained by designing multi-concentration gradient heating-cooling cycle experiments,abnormal samples were eliminated using the isolation forest algorithm,and the effects of various preprocessing methods on model performance were systematically evaluated.The results show that partial least squares regression(PLSR)exhibits superior generalization ability compared to other models.Vibrational bands corresponding to C=O and–NO_(2)were identified as key predictors for concentration estimation.This work provides an efficient and reliable solution for real-time concentration monitoring during NTO crystallization and holds significant potential for process analytical applications in energetic material manufacturing. 展开更多
关键词 ATR-FTIR spectroscopy Machine learning quantitative analysis
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An economical and flexible chip using surface-enhanced infrared absorption spectroscopy for pharmaceutical detection:Combining qualitative analysis and quantitative detection
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作者 Jikai Wang Pengfei Zeng +3 位作者 Haitao Xie Suisui He Xilin Xiao Cuiyun Yu 《Journal of Pharmaceutical Analysis》 2025年第2期474-476,共3页
Infrared(IR)spectroscopy,a technique within the realm of molecular vibrational spectroscopy,furnishes distinctive chemical signatures pivotal for both structural analysis and compound identification.A notable challeng... Infrared(IR)spectroscopy,a technique within the realm of molecular vibrational spectroscopy,furnishes distinctive chemical signatures pivotal for both structural analysis and compound identification.A notable challenge emerges from the misalignment between the mid-IR light wavelength range and molecular dimensions,culminating in a constrained absorption cross-section and diminished vibrational absorption coefficients(Supplementary data). 展开更多
关键词 pharmaceutical detection quantitative detection structural analysis surface enhanced infrared absorption spectroscopy qualitative analysis chemical signatures infrared spectroscopy molecular vibrational spectroscopyfurnishes
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Quantitative biomechanical analysis of ureteral obstruction and peristalsis
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作者 Lin Zhu Qiao Li +2 位作者 Yuanming Gao Lizhen Wang Yubo Fan 《Acta Mechanica Sinica》 2025年第4期165-175,共11页
Malignant ureteral obstruction may lead to renal function damage,renal colic,and infection.The impact of obstructive development on ureteral peristalsis was rarely studied,which requires further investigation.This stu... Malignant ureteral obstruction may lead to renal function damage,renal colic,and infection.The impact of obstructive development on ureteral peristalsis was rarely studied,which requires further investigation.This study used theoretical biomechanical methods to study the motion characteristics of the ureteral wall and obtained the radial motion equation of the ureteral wall.The motion equation was solved by 4-5th order Runge Kutta method.Analyze the motion equation of the ureteral wall,derive the expression for malignant obstructive ureteral pressure,as well as the analytical expressions for radial displacement and circumferential stress of the ureteral wall.By analyzing the radial motion equation of the ureter,it can be found that peristalsis is influenced by the pressure difference between inside and outside.The analytical solutions for radial displacement and stress contained exponential terms.Under the condition of 50%obstruction,the displacement and stress of the ureter were reduced by 90.53%and 81.10%,respectively.This study established the radial motion equation of the ureter and provided analytical solutions for the radial displacement and stress of the obstructed ureter.Based on the radial motion equation of the ureter,the radial motion characteristics of the ureteral wall were explored,including peristalsis and disappearance of peristalsis.This study provided a quantitative relationship between ureteral obstruction and peristalsis.As the degree of obstruction increased,ureteral peristalsis gradually weakened or even disappeared. 展开更多
关键词 URETER Fluid-solid coupling Nonlinear analysis Malignant ureteral obstruction Lagrangian-Euler method
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Qualitative and quantitative analysis of four different polarity fractions from Huang-Lian-Jie-Du-Decoction by HPLC-DAD-ESI-MS/MS and their related neuroprotective effects 被引量:6
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作者 杨阳 赵海誉 +4 位作者 王宏洁 宋建芳 杨健 司南 边宝林 《Journal of Chinese Pharmaceutical Sciences》 CAS CSCD 2013年第4期334-341,共8页
Huang-Lian-Jie-Du-Decoction (HLJDD) has been widely used for the treatment of Alzheimer's disease (AD) in clinic. However, the relationship between its chemical profile and neuroprotective bioactivity was not cle... Huang-Lian-Jie-Du-Decoction (HLJDD) has been widely used for the treatment of Alzheimer's disease (AD) in clinic. However, the relationship between its chemical profile and neuroprotective bioactivity was not clearly clarified yet. In present study, the water extract of HLJDD and subsequent three polarity fractions divided by different reagents were investigated. A total of 17 chromatographic peaks were confirmed by comparison with standards and their UV, MS spectra. Among them, 11 major compounds were determined by HPLC-DAD method with good linear regression relationship (r2, 0.9994-0.9999), precisions (inter-day precision RSD, 0.79%-1.07%; intra-day precision RSD, 1.59%-2.10%), repeatability (RSD, 1.66%-3.67%), stability (RSD, 1.26%-4.77%) and recovery (95.24%-105.41%, RSD, 0.29%-2.69%). Furthermore, PC12 cells and primary neurons cells were used for the neuroprotective effective assessment of aforementioned four samples from HLJDD. 3"he total aqueous extract and n-butanol extract of HLJDD presented more significant effects than the other two parts. According to their quality and quantity determination results, iridoids and alkaloids have a positive correlation with the neuroprotective effectiveness of HLJDD. 展开更多
关键词 Huang-Lian-Jie-Du-Decoction Qualitative and quantitative analysis Neuroprotective effects
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Quantitative analysis of astragaloside IV in traditional Chinese medicine‘Huang-Qi-Si-Wu' Capsules by HPLC/UV 被引量:6
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作者 张艳利 杨兴鑫 李晓妮 《Journal of Chinese Pharmaceutical Sciences》 CAS 2010年第3期223-228,共6页
A reliable and accurate HPLC/UV method was developed for the quantitative determination of astragaloside IV in 'Huang-Qi-Si-Wu' Capsules, a widely used prescription of traditional Chinese medicines (TCM). The chro... A reliable and accurate HPLC/UV method was developed for the quantitative determination of astragaloside IV in 'Huang-Qi-Si-Wu' Capsules, a widely used prescription of traditional Chinese medicines (TCM). The chromatographic separation conditions employed for HPLC/UV were optimized using a Hypersil-ODS column (250 mm^4.6 mm, 5.0 pm) with isocratic elution. Acetonitrile-water (32:68, v/v) were used as the mobile phase pumped at a flow rate of 1.0 mL/min and a detection wavelength at 203 nm was used. The method was fully validated with respect to linearity, precision, accuracy, specificity and robustness. The validated method was applied successfully to the quantification of astragaloside IV in the extract of 'Huang-Qi- Si-Wu' Capsules from different production batches. The results indicate that the established HPLC/UV method is suitable for the quantitative analysis and quality control of 'Huang-Qi-Si-Wu' Capsules and other related botanical drugs. 展开更多
关键词 HPLC/UV quantitative analysis Astragaloside IV Radix Astragali 'Huang-Qi-Si-Wu' Capsules
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Evaluation of the protective effects of Crocus sativus L.against cypermethrin induced reproductive toxicity in male rats through the Nrf2 pathway and in silico ADMET analysis
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作者 Fareena Tariq Farah Ijaz +9 位作者 Yasameen Hameed Jasim Farah Naz Channa Sohail Ahmed Ahmed Shandookh Hameed Sobia Alyas Ahmed Raheem Rayshan Tahira Bibi Nazima Yousaf Khan Sadia Bibi Jameel Ahmed Buzdar 《Traditional Medicine Research》 2026年第3期12-25,共14页
Background:Epidemiological studies have confirmed that longer exposure to insecticides like cypermethrin(CYP)significantly increases the risk of male reproductive toxicity.Crocus sativus L.has been recognized due to i... Background:Epidemiological studies have confirmed that longer exposure to insecticides like cypermethrin(CYP)significantly increases the risk of male reproductive toxicity.Crocus sativus L.has been recognized due to its therapeutic properties,but its exact role and molecular mechanisms in treatment of reproductive dysfunction remain unclear.Methods:During this study,36 rats were randomly divided into six groups(n=6):control,CYP-induced(60 mg/kg),standard(leuprolide 3 mg/kg)and three treatment groups receiving aqueous,ethanolic,and oil extracts(50 mg/kg or 20 mL/kg)for post-toxicity induction.Results:The finding represented that exposure of CYP significantly increased oxidative stress,disrupted testicular architecture,and markedly reduced testosterone levels(P<0.05).Importantly,Crocus sativus L.treatment alleviated these changes by increasing the expression of Nrf2(nuclear factor erythroid 2-related factor 2),restoring the activity of antioxidant enzymes,and enhancing testicular histomorphology.Surprisingly,molecular docking established a high binding affinity of Crocus sativus L.phytoconstituents such as gallic acid,cinnamic acid and quercetin to the Nrf2-Keap1 complex.It is worth noting that,Crocus sativus L.exhibited a high level of protection against reproductive toxicity caused by CYP in male rats,which was mediated by the activation of Nrf2 pathway,reduction of oxidative damage,and favorable ADMET characteristics.Conclusion:Notably,this research provides a more valid,safe,and effective method of developing new drugs for reproductive disorders,however,further investigation is needed to support the research findings and implement it in clinical practice. 展开更多
关键词 Crocus sativus L. CYPERMETHRIN male reproductive toxicity Nrf2 pathway in silico ADMET analysis
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Changes in border-associated macrophages after stroke: Single-cell sequencing analysis
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作者 Ning Yu Yang Zhao +3 位作者 Peng Wang Fuqiang Zhang Cuili Wen Shilei Wang 《Neural Regeneration Research》 2026年第1期346-356,共11页
Border-associated macrophages are located at the interface between the brain and the periphery, including the perivascular spaces, choroid plexus, and meninges. Until recently, the functions of border-associated macro... Border-associated macrophages are located at the interface between the brain and the periphery, including the perivascular spaces, choroid plexus, and meninges. Until recently, the functions of border-associated macrophages have been poorly understood and largely overlooked. However, a recent study reported that border-associated macrophages participate in stroke-induced inflammation, although many details and the underlying mechanisms remain unclear. In this study, we performed a comprehensive single-cell analysis of mouse border-associated macrophages using sequencing data obtained from the Gene Expression Omnibus(GEO) database(GSE174574 and GSE225948). Differentially expressed genes were identified, and enrichment analysis was performed to identify the transcription profile of border-associated macrophages. CellChat analysis was conducted to determine the cell communication network of border-associated macrophages. Transcription factors were predicted using the ‘pySCENIC' tool. We found that, in response to hypoxia, borderassociated macrophages underwent dynamic transcriptional changes and participated in the regulation of inflammatory-related pathways. Notably, the tumor necrosis factor pathway was activated by border-associated macrophages following ischemic stroke. The pySCENIC analysis indicated that the activity of signal transducer and activator of transcription 3(Stat3) was obviously upregulated in stroke, suggesting that Stat3 inhibition may be a promising strategy for treating border-associated macrophages-induced neuroinflammation. Finally, we constructed an animal model to investigate the effects of border-associated macrophages depletion following a stroke. Treatment with liposomes containing clodronate significantly reduced infarct volume in the animals and improved neurological scores compared with untreated animals. Taken together, our results demonstrate comprehensive changes in border-associated macrophages following a stroke, providing a theoretical basis for targeting border-associated macrophages-induced neuroinflammation in stroke treatment. 展开更多
关键词 border-associated macrophages CLODRONATE hypoxia ISCHEMIA-REPERFUSION ischemic stroke liposomes neuroinflammation single-cell sequencing analysis STAT3 tumor necrosis factor
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Real-time Quantitative PCR Analysis of Vascular Endothelial Growth Factor Receptor-2(VEGFR-2) Expression at Zebrafish Different Developmental Stages 被引量:2
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作者 孙桂金 潘杰 +2 位作者 刘可春 王雪 王思锋 《Agricultural Science & Technology》 CAS 2010年第4期118-120,共3页
[Objective]To investigate the expression of zebrafish vascular endothelial growth factor-2(VEGFR-2) at different developmental stages.[Method]Total RNAs were extracted from 12,24,48,72 and 96 hpf stage zebrafish emb... [Objective]To investigate the expression of zebrafish vascular endothelial growth factor-2(VEGFR-2) at different developmental stages.[Method]Total RNAs were extracted from 12,24,48,72 and 96 hpf stage zebrafish embryos and larvae.Real-time quantitative RT-PCR was performed to examine the expression of VEGFR-2.The data were analyzed by 2^-△△Ct method.[Result]The expression level of VEGFR-2 gene increased gradually from 12 to 72 hpf,and subsequently decreased at 96 hpf.The expression level was lowest at 12 hpf,highest at 72 hpf,and had significant differences when compared with that of other developmental stages.[Conclusion]The expression level of VEGFR-2 increases gradually before blood vessel maturation and decreases as blood vessels mature. 展开更多
关键词 ZEBRAFISH Real-time quantitative PCR VEGFR-2
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Application of Statistic Analysis on the Selection of Quantitative Characteristics Listed in the DUS Test Guideline of Tagetes L. 被引量:1
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作者 刘艳芳 张建华 +6 位作者 杨晓洪 王江民 李彦刚 陈海荣 李向东 张惠 管俊娇 《Agricultural Science & Technology》 CAS 2012年第9期2021-2023,2033,共4页
[Objective] This paper researched how to use specific approach to select quantitative characteristics which would be listed in the DUS Test Guideline of Tagetes L. [Method] With the aid of statistic analysis, the unif... [Objective] This paper researched how to use specific approach to select quantitative characteristics which would be listed in the DUS Test Guideline of Tagetes L. [Method] With the aid of statistic analysis, the uniformity, stability and correlation of 14 pre-selected characteristics were analyzed. [Result] The expression of peduncle length of terminal flower had low uniformity within a variety; the expres- sion of main stem thickness was not stable in continuous growing cycles; there were four pairs of quantitative characteristics which are (very) significantly correlated, namely, leaf length and leaf width, diameter of flower head and length of outer ligu- late floret, number of ligulate floret whorls and number of ligulate floret, leaf width and width of terminal leaflet of pinnate leaves. Based on the requirements of char- acteristic selection and the results of statistic analysis, five characteristics including peduncle length of terminal flower, thickness of the main stem, leaf width, length of outer ligulate floret and number of ligulate floret were deleted. [Conclusion] For the first time, this paper introduced the application of statistic analysis on the selection of quantitative characteristics. 展开更多
关键词 DUS Test Guideline of Tagetes L. quantitative characteristic Statisticanalysis
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Quantitative Analysis of Land Use Landscape Pattern in Shihezi Desert Oasis
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作者 王玲 吕新 高秀平 《Journal of Landscape Research》 2009年第3期49-54,81,共7页
Based on the land use status map of Shihezi City,the land use landscape map of Shihezi City was made with the support of GIS then many landscape indices were selected to quantitatively analyze the landscape pattern ch... Based on the land use status map of Shihezi City,the land use landscape map of Shihezi City was made with the support of GIS then many landscape indices were selected to quantitatively analyze the landscape pattern characteristics of Shihezi Oasis from three aspects of landscape diversity index,landscape space configuration index and plaque characteristics index. The results showed that the main plaque types of the landscape in Shihezi reclamation area are arable land and water areas,which totally account for 58% of the total area; farmland,gardens,woodland,urban sites,industrial and mining land use were embedded in this oasis landscape in the form of mosaics,and their fractal index was high due to the strong impact of human activities; arable land and mining land distribution was scattered,but marshes and other uncultivated land were relatively concentrated. The dominance degree of the landscape was low because there was no advantageous type in this landscape and all patches distributed equably which was easily to be disturbed so that the whole landscape was unstable. Comprehensively speaking,the landscape in Shihezi region was rather complicate,and its diversity index,fragmentation degree and heterogeneity were high. 展开更多
关键词 Shihezi RECLAMATION area DESERT OASIS LANDSCAPE PATTERN LANDSCAPE index quantitative analysis
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Quantitative Allocation Analysis of "Raising by Planting" System Combining Fruits and Poultry for Mountainous Region in Headwaters of Dongjiang River
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作者 方钲 席运官 +1 位作者 刘明庆 李德波 《Agricultural Science & Technology》 CAS 2012年第3期592-595,共4页
[Objective] The aim was to promote nutrient cycling and utilization in the mountain's system combining fruits and poultry and to control non-point source pollution produced from swine raising and navel orange plantin... [Objective] The aim was to promote nutrient cycling and utilization in the mountain's system combining fruits and poultry and to control non-point source pollution produced from swine raising and navel orange planting in headwaters of Dongjiang River. [Method] The quantitative analysis was mainly conducted for the so called "raising by planting" which is about material cycle in "pig-methane-fruit-fish" model and energy cascade utilization, based on relationship between excreted amount by livestock and the utilized quantity in Xinlin Farm in Longtang Town, Dingnan County, Jiangxi Province. [Result] Considering N requirement by fruit trees, a navel orange orchard (1 mu) could support about 2.72 pigs, the equipped biogas pool (1.88 m3) could support 1 166.67 kg of duckweeds and a fish pond could support 25.57 grass carps. In contrast, a satsuma orchard (1 mu) could support about 1.96 pigs, the equipped biogas pool (1.35 m3) could support 841.53 kg duckweeds and the fish pond could support 18.44 grass carps. [Conclusion] The results provided scientific references for quantitative allocation of members in "pig-methane-fruit-fish" model when popularized in headwaters of Dongjiang River. 展开更多
关键词 Headwaters of Dongjiang River "Raising by planting" "Pig-methane- fruit-fish" model quantitative allocation
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Qualitative and Quantitative Analysis of Alkaloids in Cortex Phellodendri by HPLC-ESI-MS/MS and HPLC-DAD 被引量:20
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作者 ZHU Shuang-lai DOU Sheng-shan +6 位作者 LIU Xin-ru LIU Run-hui ZHANG Wei-dong HUANG Hong-lin ZHANG Yi HU Yao-hua WANG Shu-ping 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2011年第1期38-44,共7页
A combined method of high performance liquid chromatograph-elecrtrospray-ionization mass spectrometer(HPLC-ESI-MS/MS) coupled with a photodiode array detector(HPLC-DAD) and principal component analysis(PCA) was ... A combined method of high performance liquid chromatograph-elecrtrospray-ionization mass spectrometer(HPLC-ESI-MS/MS) coupled with a photodiode array detector(HPLC-DAD) and principal component analysis(PCA) was applied to the qualitative and quantitative analyses of alkaloids in Cortex Phellodendri(CP) samples, and to the differentiation of two species of CP, Cortex Phellodendri Chinensis(CPC) and Cortex Phellodendri Amurensis(CPA). Twenty-two peaks appeared in the HPLC-MS base peak chromatogram of CP detected by the HPLC-ESI-MS/MS analysis, and the alkaloids were identified according to the MSn data, the known MS fragmentation rules and the literature data. Five alkaloids including berberine, palmatine, jatrorrhizine, phellodendrine and magnoflorine were simultaneously determinated by the HPLC-DAD. Berberine was the primary component in all CP samples, and the contents of berberine and palmatine were exploited to be two critical parameters for effective discrimination between the two species of CP. The average content of berberine in CPC(58.75 mg/g) was higher than that in CPA(9.16 mg/g), while the content of palmatine was less, only 0.25 mg/g in CPC and 4.19 mg/g in CPA. With the use of PCA, samples datasets were separated successfully into two different clusters corresponding to the two species, and berberine, pahnatine, phellodendrine and magnoflorine contribute most to the above mentioned calssifying . The proposed method oroved to be a useful tool in the aualitv control of Chinese herbal medicines. 展开更多
关键词 Cortex Phellodendri ALKALOID HPLC-ESI-MS/MS quantitative analysis Qualitative analysis Principal component analysis
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Change of choline compounds in sodium selenite-induced apoptosis of rats used as quantitative analysis by in vitro 9.4T MR spectroscopy 被引量:14
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作者 Zhen Cao Lin-Ping Wu +3 位作者 Yun-Xia Li Yu-Bo Guo Yao-Wen Chen Ren-Hua Wu 《World Journal of Gastroenterology》 SCIE CAS CSCD 2008年第24期3891-3896,共6页
AIM: To study liver cell apoptosis caused by the toxicity of selenium and observe the alteration of choline compounds using in vitro 9.4T high resolution magnetic resonance spectroscopy. METHODS: Twenty male Wistar ra... AIM: To study liver cell apoptosis caused by the toxicity of selenium and observe the alteration of choline compounds using in vitro 9.4T high resolution magnetic resonance spectroscopy. METHODS: Twenty male Wistar rats were randomly divided into two groups. The rats in the treatment group were intraperitoneally injected with sodium selenite and the control group with distilled water. All rats were sacrifi ced and the livers were dissected. 1H-MRS data were collected using in vitro 9.4T high resolution magnetic resonance spectrometer. Spectra were processed using XWINNMR and MestRe-c 4.3. HE and TUNEL staining was employed to detect and confi rm the change of liver cells. RESULTS: Good 1H-MR spectra of perchloric acid extract from liver tissue of rats were obtained. The conventional metabolites were detected and assigned. Concentrations of different ingredient choline compounds in treatment group vs control group were as follows: total choline compounds,5.08 ± 0.97 mmol/L vs 3.81 ± 1.16 mmol/L (P = 0.05); and free choline,1.07 ± 0.23 mmol/L vs 0.65 ± 0.20 mmol/L (P = 0.00). However,there was no statistical signif icance between the two groups. The hepatic sinus and cellular structure of hepatic cells in treatmentgroup were abnormal. Apoptosis of hepatic cells was confi rmed by TUNEL assay. CONCLUSION: High dose selenium compounds can cause the rat liver lesion and induce cell apoptosis in vivo. High resolution 1H-MRS in vitro can detect diversified metabolism. The changing trend for different ingredient of choline compounds is not completely the same at early period of apoptosis. 展开更多
关键词 Apoptosis of liver cell Choline compounds Sodium selenite In vitro ^1H-MRS quantitative analysis
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Analysis of Quantitative Trait Loci for Starch Properties of Rice Based on an RIL Population 被引量:11
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作者 包劲松 Harold CORKE +1 位作者 何平 朱立煌 《Acta Botanica Sinica》 CSCD 2003年第8期986-994,共9页
Rice (Oryza sativa L.) eating and cooking quality is mainly influenced by its starch properties. Mapping quantitative trait loci (QTL) for starch properties not only helps us understand their genetic basis leading to ... Rice (Oryza sativa L.) eating and cooking quality is mainly influenced by its starch properties. Mapping quantitative trait loci (QTL) for starch properties not only helps us understand their genetic basis leading to acceleration of quality improvement, but also helps us find possible genes participating in the synthesis of starch. A recombinant inbred line (RIL) population consisting of 107 lines, derived from an indica (Zaiyeqing 8, ZYQ 8) and a japonica (Jingxi 17, JX 17) rice, was used to investigate the genetic factors affecting starch quality parameters, such as apparent amylose content (AAC), gel consistency (GC), starch pasting viscosity parameters, gel textural properties, gelatinization temperature (GT) and starch retrogradation properties. A total of 44 QTLs covered chromosomes 2-6, 8, 9 and 11 were detected for the 22 traits, with at least one QTL and as many as four QTLs for each individual trait. The results indicated that two major genes were responsible for most starch property traits. The Wx gene that encodes granule bound starch synthase on chromosome 6 was significant for AAC, GC, starch pasting viscosity parameters, gel textural properties and starch retrogradation properties. The alk gene linked with Wx on chromosome 6 was significant for starch gelatinization temperature characteristics. All other QTLs were minor genes. One QTL on chromosome 9 flanked by RZ404 and G295 was significant for gel hardness (HD), gumminess (GUM), chewiness (CHEW), peak temperature of retrogradated starch (RTp), and percentage retrogradation (R%) and all these traits were not tested before. 展开更多
关键词 ALK eating and cooking quality quantitative trait locus RICE STARCH WX
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Quantitative Analysis of Moisture Effect on Black Soil Reflectance 被引量:8
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作者 LIU Huan-Jun ZHANG Yuan-Zhi +4 位作者 ZHANG Xin-Le ZHANG Bai SONG Kai-Shan WANG Zong-Ming TANG Na 《Pedosphere》 SCIE CAS CSCD 2009年第4期532-540,共9页
Several studies have demonstrated that soil reflectance decreases with increasing soil moisture content, or increases when the soil moisture reaches a certain content; however, there are few analyses on the quantitati... Several studies have demonstrated that soil reflectance decreases with increasing soil moisture content, or increases when the soil moisture reaches a certain content; however, there are few analyses on the quantitative relationship between soil reflectance and its moisture, especially in the case of black soils in northeast China. A new moisture adjusting method was developed to obtain soil reflectance with a smaller moisture interval to describe the quantitative relationship between soil reflectance and moisture. For the soil samples with moisture contents ranging from air-dry to saturated, the changes in soil reflectance with soil moisture can be depicted using a cubic equation. Both moisture threshold (MT) and moisture inflexion (MI) of soil reflectance can also be determined by the equation. When the moisture range was smaller than MT, soil reflectance can be simulated with a linear model. However, for samples with different soil organic matter (OM), the parameters of the linear model varied regularly with the OM content. Based on their relationship, the soil moisture can be estimated from soil reflectance in the black soil region. 展开更多
关键词 black soil quantitative analysis remote sensing soil moisture spectral reflectance
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Simultaneous determination of five phenylethanoid glycosides in Cistanches Herba using quantitative analysis of multi-components by single marker 被引量:10
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作者 Ruiyan Li Mingbo Zhao +1 位作者 Pengfei Tu Yong Jiang 《Journal of Chinese Pharmaceutical Sciences》 CAS CSCD 2019年第8期537-546,共10页
In the present study, a method for the quantitative analysis of multi-components by single marker(QAMS) has been developed and validated for the simultaneous determination of echinacoside(ECH), tubuloside A, acteoside... In the present study, a method for the quantitative analysis of multi-components by single marker(QAMS) has been developed and validated for the simultaneous determination of echinacoside(ECH), tubuloside A, acteoside, isoacteoside, and2’-acetylacteoside in Cistanches Herba. ECH was used as the internal standard(IS) to obtain the relative correction factors(RCFs) of the other four phenylethanoid glycosides(PhGs);meanwhile, various influencing factors on RCFs were investigated under different conditions. The content of each component was calculated with RCF. The results were compared with those obtained by the external standard method(ESM) to verify the feasibility and accuracy of the established QAMS method. No significant difference was found in the quantitative results of 10 batches of Cistanches Herba between QAMS and ESM. The proposed QAMS method for simultaneous determination of PhGs in Cistanches Herba is accurate and feasible, providing an efficient and economical approach for the quality control of Cistanches Herba. 展开更多
关键词 Cistanches Herba Phenylethanoid glycosides quantitative analysis of multi-components by single-marker Relative correction factors
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