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Metallized Film Capacitors (MFC) are vital devices in many important fields such as energy, transportation, and aviation, whilst Digital Twin (DT) technology opens a new channel to leverage existing data resources of metallized film capacitors. This paper review current knowledge about metallized film capacitors and digital twin, list the key issues, propose frameworks, and provide the outlook to clarify the potential of digital twin’s application in metallized film capacitors. First, based on the development history and research status of metallized film capacitors, this review sorts out the key research issues of data utilization. Then, the connotation and typical characteristics of the digital twin definition are combed and refined, and the typical architecture of digital twin implementation is presented. Furthermore, the overall application architecture of digital twin in metallized film capacitors is constructed, and the technology system of each application scenario and the role of digital twin are analyzed. Finally, the main challenges in the application of the digital twin in metallized film capacitors and the future development directions are discussed. This review promotes the performance improvement, cost reduction and application expansion of metallized film capacitors, which can be used as a guide for the application of digital twin in other power equipment of energy system.

Early identification of cerebrovascular atherosclerotic ischemic stroke is necessary for accurate treatment and clinical research.To identify novel predictors and build a predictive model of ischemic strokes due to cerebrovascular atherosclerosis.MIMIC-IV database was used to search for clinical data of patients with ischemic stroke. Included patients were divided into two groups according to their etiologies. Univariate and multivariate logistic regressions were used to build the predictive model, and the model reliability parameters were calculated. The cut-off value for the model was selected according to the Youden index. Clinical data from the Neurovascular Center of Changhai Hospital were used to verify the predictive model.Logistical regressions showed a positive correlation between advanced age, peripheral atherosclerosis, history of transient ischemia, and the diagnosis of ischemic strokes due to cerebrovascular atherosclerosis. The history of atrial fibrillation, levels of the National Institutes of Health Stroke Scale, serum potassium, and activated partial thromboplastin time were negatively correlated to the diagnosis of cerebrovascular atherosclerotic ischemic stroke. The predictive model was constructed from logistic regression results, and the area under the curve was 0.764. The cut-off value for the model was set at 0.089 to achieve the highest Youden index, with sensitivity and specificity of 75.9% and 64.1%. Clinical verification of the model revealed that the sensitivity and specificity of the model were 52.5% and 93.0% respectively.The efficacy of the predictive model was acceptable as an aid in predicting cerebrovascular atherosclerotic ischemic stroke.

AimsThis study aimed to build a prediction model to early diagnose intracranial atherosclerosis (ICAS)-related large vascular occlusion (LVO) in acute ischemic stroke patients before digital subtractive angiography.MethodsPatients enrolled in the DIRECT-MT trial (NCT03469206) were included in our secondary analysis and distributed into ICAS-LVO and non-ICAS-LVO groups. We also retrieved demographic data, medical histories, clinical characteristics, and pre-operative imaging data. Hypothesis testing was used to compare data of the two groups, and univariate logistic regression was used to identify the predictors of ICAS-LVO primarily. Then, we used multivariate logistic regression to determine the independent predictors and formulate the prediction model. Model efficacy was estimated by the area under the receiver operating characteristic (ROC) curve (AUC) and diagnostic parameters generated from internal and external validations.ResultsThe subgroup analysis included 45 cases in the ICAS-LVO group and 611 cases in the non-ICAS-LVO group. Variates with p < 0.1 in the comparative analysis were used as inputs in the univariate logistic regression. Next, variates with p < 0.1 in the univariate logistic regression were used as inputs in the multivariate logistic regression. The multivariate logistic regression indicated that the atrial fibrillation history, hypertension and smoking, occlusion located at the proximal M1 and M2, hyperdense artery sign, and clot burden score were related to the diagnosis of ICAS-LVO. Then, we constructed a prediction model based on multivariate logistics regression. The sensitivity and specificity of the model were 84.09 and 74.54% in internal validation and 73.11 and 71.53% in external validation.ConclusionOur current prediction model based on clinical data of patients from the DIRECT-MT trial might be a promising tool for predicting ICAS-LVO.

Polymer dielectrics for energy storage applications usually endure high electric field strength. Adjustment of the composition and structure of the dielectric bulk phase to enhance the dielectric breakdown strength has been widely studied. However, the effect of electrode–dielectric interface on the breakdown strength has received little attention, which greatly hinders further development in this field. In this work, an all-organic double-layer dielectric film consisting of poly(vinylidene fluoride) (PVDF) as the matrix and polymethyl methacrylate (PMMA) as the organic nano-interlayer was prepared. By adjusting the electrode–dielectric interface, remarkably improved electric breakdown strength (767.05 MV m−1) and discharged energy density (19.08 J cm−3) were realized concurrently without sacrificing the charge–discharge efficiency. The experimental results and computational simulations reveal that the surface morphology of dielectrics has a great effect on the electric field distribution at the electrode–dielectric interface, and further affects the leakage current and breakdown strength of the dielectric. The PMMA nano-interlayer modifies the surface defects and increases the Young's modulus at the electrode–dielectric interface, leading to the improvement of insulation performance. These findings offer a new perspective to understand the impact of the electrode–dielectric interface on the polymer dielectric breakdown strength. This work provides a novel paradigm for fabricating polymer dielectrics with high breakdown strength for energy storage.

In this letter, the concept of high-gain multifunctional antenna based on folded reflectarray antenna (FRA) and polarization-sensitive frequency selective surface (FSS) is proposed. Antenna with multiple functions can be realized by using a polarization-sensitive FSS as the subreflector of FRA instead of the traditional polarizing grid. To validate this concept, a high-gain filtering antenna designed at Ka -band is presented as a design example. Good filtering performance of the antenna has been achieved due to the frequency selective characteristics of FSS. Besides, the relationship between the focal-length-to-diameter ( F/D ) ratio of FRA and the size of FSS element has also been discussed.

The ultra-performance liquid chromatography-quadrupole time-of-flight mass spectrometry(UPLC-Q-TOF-MS~E) technology was employed to compare the chemical components between the aerial and underground parts of Coptis chinensis samples from different batches. According to the retention time, molecular ion peak, and LC-MS~E fragment information of the reference substances and available literature, we identified a total of 40 components. Thirty-three and 31 compounds were respectively identified in the underground part(taproots) and the aerial part(stems and leaves) of C. chinensis. Among them, 24 compounds, including alkaloids(e.g., berberine and jatrorrhizine) and phenolic acids(e.g., chlorogenic acid, quinic acid, and tanshinol), were common in the two parts. In addition, differential components were also identified, such as magnoline glucoside in the underground part and(±) lariciresionol-4-β-D-glucopyranoside in the aerial part. The analysis of fragmentation pathways based on spectra of reference substances indicated the differences among samples of different batches. Furthermore, we performed the principal component analysis(PCA) for the peak areas of C. chinensis in different batches. The results showed that the underground part and the aerial part were clearly clustered into two groups, indicating that the chemical components contained in the two parts were different. Furthermore, the results of partial least squares discriminant analysis(PLS-DA) identified 31 differential compounds(VIP valuegt;1) between the underground part and the aerial part, mainly including alkaloids, phenolic acids, lignans, and flavonoids. This study proves that C. chinensis possesses great development potential with multiple available compounds in stems and leaves. Moreover, it sheds light on for the development and utilization of non-medicinal organs of C. chinensis and other Chinese medicinal herbs.

With the development of advanced electronic devices and electric power systems, polymer-based dielectric film capacitors with high energy storage capability have become particularly important. Compared with polymer nanocomposites with widespread attention, all-organic polymers are fundamental and have been proven to be more effective choices in the process of scalable, continuous, and large-scale industrial production, leading to many dielectric and energy storage applications. In the past decade, efforts have intensified in this field with great progress in newly discovered dielectric polymers, fundamental production technologies, and extension toward emerging computational strategies. This review summarizes the recent progress in the field of energy storage based on conventional as well as heat-resistant all-organic polymer materials with the focus on strategies to enhance the dielectric properties and energy storage performances. The key parameters of all-organic polymers, such as dielectric constant, dielectric loss, breakdown strength, energy density, and charge-discharge efficiency, have been thoroughly studied. In addition, the applications of computer-aided calculation including density functional theory, machine learning, and materials genome in rational design and performance prediction of polymer dielectrics are reviewed in detail. Based on a comprehensive understanding of recent developments, guidelines and prospects for the future development of all-organic polymer materials with dielectric and energy storage applications are proposed.

The dried fruit body of Phylloporia ribis(Hymenochaetaceae), which prefers to live on the stumps of Lonicera japonica(Caprifoliaceae), has a variety of activities, whereas its pharmacodynamic material basis is not completely clear and there are few reports on its quality control and evaluation. In this study, an UPLC-Q-TOF-MS method was used to analyze the nucleosides and nucleobases in P. ribis and a HPLC method was established for simultaneous determination of 10 nucleosides and nucleobases. MS and MS/MS data were acquired in positive ion mode. Based on the data comparison of the sample and the reference substance, the literature data and the compound databases of ChemSpider and PubChem, 18 nucleosides and nucleobases were identified qualitatively from the water extract of P. ribis for the first time. After optimization, the HPLC was performed using a Welch Ultimate AQ C_(18) column(4.6 mm×250 mm, 5 μm) by gradient elution with acetonitrile and water as mobile phase, the flow rate of 1.0 mL·min~(-1), the detection wavelength of 260 nm, and the column temperature of 30 ℃. Through the investigation of the extraction method, solvent and time, it was determined that the test solution should be obtained by cold water extraction for 18 h. At the present HPLC conditions, 10 components of uracil, cytidine, hypoxanthine, uridine, thymine, inosine, guanosine, 2'-deoxyinosine, 2'-deoxyguanosine and thymidine could be well separated(Rgt; 1.5) and showed good linearity(rgt; 0.999 9) in the concentration ranges of 0.247-24.7, 0.283-28.3, 0.273-27.3, 0.256-25.6, 0.257-25.7, 0.318-31.8, 0.245-24.5, 0.267-26.7, 0.250-25.0 and 0.267-26.7 mg·L~(-1), respectively. The average reco-veries of 10 components were 95.78%-104.5%, and the RSDs were 2.2%-5.2%(n=6). The contents of 10 nucleosides and nucleobases in different samples of P. ribis varied greatly, which were 0.021-0.122, 0.004-0.029, 0.014-0.226, 0.009-0.442, 0.003-0.014, 0.002-0.146, 0.007-0.098, 0-0.054, 0.005-0.069, 0.004-0.081 and 0.072-1.28 mg·g~(-1) for uracil, cytidine, hypoxanthine, uridine, thymine, inosine, guanosine, 2'-deoxyinosine, 2'-deoxyguanosine, thymidine and total 10 components, respectively. These results demonstrated that the components had significant differences in the internal quality, and good quality control was needed to ensure the medical efficacy. This study provides a scientific basis for the discovery of pharmacodynamic ingredients, quality control and evaluation of P. ribis.

A novel Zn(II)-based metal–organic framework {[Zn(L)](DMF)3}n (1) was prepared by using Zn(II) ions and bifunctional imidazole carboxylate ligands (5-(1H-imidazol-1-yl)isophthalic acid, H2L). Complex 1 is a fluorescent Zn-MOF sensor with high selectivity and sensitivity for the detection of nitrobenzene. KSV can reach 2.875 × 103 M−1. The protective effect of compound 1 on the hypertension was further explored. Firstly, the RT-PCR was performed to explore the influence of compound on vdr expression in vascular endothelial cells. Then, the ELISA assay was conducted to measure the renin and angiotensin II level in vivo after compound treatment. The results obtained from molecular docking and pose scoring software exhibited a possible binding mode of the compound binding to vitamin D receptor, which might provide potential regulation mechanisms for the compound.

Chrysanthemum is widely used as a type of edible flower and also considered as the important materials of many beverages in China. Due to the occurrence of diseases and pests, and the lack of regulations for species, frequency, dose of pesticides in Chrysanthemum, pesticides have become one of the main pollutants in Chrysanthemum. The pesticide residues in Chrysanthemum were detected frequently and worth noting. This paper focused on the types of pesticides, pesticide residue detection techniques, and risk assessment methods for Chrysanthemums on the basis of relevant literatures. The pesticide residues of traditional Chinese medicine are mainly organochlorines, organophosphorus and pyrethroids, and the detection techniques include gas chromatography(GC), liquid chromatography(LC) or both combined with mass spectrometry(MS). With the increasing use of traditional Chinese medicine, Chrysanthemum is widely circulated in the market. Therefore, it is important to understand the current situation of pesticide residues in different varieties of Chrysanthemum, so as to provide theoretical reference for the control of quality and safety of Chrysanthemum and the formulation of the maximum residue limit.

Machine learning has shown its great potential in the accelerated discovery of advanced materials in the field of computational molecular design. High-temperature polymer dielectrics are urgently required with the emerging applications of energy-storage dielectric film capacitors under high-temperature conditions. Here, we demonstrate the successful prediction of polymers with a high dielectric constant ( ɛ) and high glass transition temperature ( Tg) using a Bayesian molecular design model. The model is trained on a joint data set containing 382 computed ɛ values using density functional perturbation theory and experimentally measured Tg values of ∼7000 polymers to build relative quantitative structure–property relationships and identify the promising polymers with specific desired range of dielectric constant and glass transition temperature. From the hypothetical polymer candidates, ten promising polymers are proposed based on their predicted properties and synthetic accessibility score for high-temperature dielectric film capacitors’ application. Moreover, 250k novel polymer structures are generated with the model to support future polymer informatics research. This work contributes to the successful prediction of high-temperature polymer dielectrics using machine learning models.

Similar to sampling perfection with application-optimized contrast using different flip angle evolutions (SPACE), T2-weighted fast field echo (FFE) also has a black blood effect and a high imaging efficiency. The purpose of this study was to optimize 3D_T2_FFE and compare it with 3D_T2_SPACE for carotid imaging. The scanning parameter of 3D_T2_FFE was optimized for the imaging of the carotid wall. Twenty healthy volunteers and 10 patients with carotid plaque underwent cervical 3D_T2_FFE and 3D_T2_SPACE examinations. The signal-to-noise ratios of the carotid wall (SNRwall) and lumen (SNRlumen), and the contrast-to-noise ratios between the wall and lumen (CNRwall_lumen) were compared. The incidence of the residual flow signal at the carotid bifurcation and the grades of flow voids in the cerebellopontine angle region in the two sequences were also compared. The reproducibility of the two sequences was tested. No significant difference was observed between the two sequences in terms of the SNRwall of healthy individuals and patients (P = 0.132 and 0.102, respectively). The SNRlumen in the 3D_T2_FFE images was lower than that in the 3D_T2_SPACE images. No significant difference was observed between the two sequences in terms of the CNRwall-lumen. The incidence of the residual flow signal at the carotid bifurcation in 3D_T2_FFE was significantly lower than that in 3D_T2_SPACE. The grades of flow suppression in the cerebellopontine angle region in 3D_T2_SPACE was lower than that in 3D_T2_FFE. Both sequences showed excellent inter-and intra-observer reproducibility. Compared to 3D_T2_SPACE, 3D_T2_FFE showed stronger flow suppression while maintaining good imaging quality, which can be used as an alternative tool for carotid imaging.

BackgroundHigh temperatures, particularly at night, decrease rice yield and quality. As high nighttime temperatures (HNTs) become increasingly frequent due to climate change, it is imperative to develop rice crops that tolerate HNTs. DNA methylation may represent a potential avenue for HNT-tolerant rice strain development, as this mechanism regulates gene activity and cellular phenotype in response to adverse environmental conditions without changing the nucleotide sequence.ResultsAfter HNT exposure, the methylation patterns of cytosines in the CHH context differed noticeably between two coisogenic rice strains with significantly different levels in heat tolerance. Methylation differences between strains were primarily observed on successive cytosines in the promoter or downstream regions of transcription factors and transposon elements. In contrast to the heat-sensitive rice strain, the regions 358–359 bp and 2–60 bp downstream of two basal transcriptional factors (TFIID subunit 11andmediator of RNA polymerase II transcription subunit 31, respectively) were fully demethylated in the heat-tolerant strain after HNT exposure. In the heat-tolerant strain, HNTs reversed the methylation patterns of successive cytosines in the promoter regions of various genes involved in abscisic acid (ABA)-related reactive oxygen species (ROS) equilibrium pathways, including the pentatricopeptide repeat domain genePPR(LOC_Os07g28900) and the homeobox domain genehomeobox(LOC_Os01g19694). Indeed,PRRexpression was inhibited in heat-sensitive rice strains, and the methylation rates of the cytosines in the promoter region ofPRRwere greater in heat-sensitive strains as compared to heat-tolerant strains.ConclusionsAfter HNT exposure, cytosines in the CHH context were more likely than cytosines in other contexts to be methylated differently between the heat-sensitive and heat-tolerant rice strains. Methylation in the promoter regions of the genes associated with ABA-related oxidation and ROS scavenging improved heat tolerance in rice. Our results help to clarify the molecular mechanisms underlying rice heat tolerance.

The unequal area facility layout problem (UA-FLP) is to place some objects in a specified space according to certain requirements, which is a NP-hard problem in mathematics because of the complexity of its solution, the combination explosion and the complexity of engineering system. Particle swarm optimization (PSO) algorithm is a kind of swarm intelligence algorithm by simulating the predatory behavior of birds. Aiming at the minimization of material handling cost and the maximization of workshop area utilization, the optimization mathematical model of UA-FLPP is established, and it is solved by the particle swarm optimization (PSO) algorithm which simulates the design of birds' predation behavior. The improved PSO algorithm is constructed by using nonlinear inertia weight, dynamic inertia weight and other methods to solve static unequal area facility layout problem. The effectiveness of the proposed method is verified by simulation experiments.

Taking Lonicerae Japonicae Flos as an example, the method ofquot;expert consensus of different regionsquot; was used to screen the representative samples and evaluate their commodity grades. The correlation analysis, hierarchical cluster analysis and partial least squares discriminant analysis(PLS-DA) ofquot;commodity grade-appearance characteristic-component contentquot; were carried out to reveal the scientificity of traditional commodity grade of Chinese medicinal material. By referring to the existing literature and the grade investigation from the sample collection regions, 78quot;initial gradequot; samples were screened out from 118 collected samples. Authoritative experts from four regions(n=4) including Linyi(Shangdong province), Bozhou(Anhui province), Anguo(Hebei province) and Beijing were organized to evaluate their commodity grades, separately. Based on the grade consistency rate(R_i≥70%), 69quot;local gradequot; samples were screened out from thequot;initial gradequot; samples. Based on the average grade consistency rate ■quot;authoritative gradequot; samples were screened out from thequot;local gradequot; samples, including15 first-grade samples, 9 second-grade samples, 11 third-grade samples and 17 fourth-grade samples. For thesequot;authoritative gradequot; samples, the main appea-rance characteristics were quantified and the contents of 13 components were determined by ultra performance liquid chromatography(UPLC). Furthermore, the total contents of 6 phenolic acids, 4 flavonoids and 3 iridoids were calculated, respectively. The results of correlation analysis showed that 4 appearance characteristics indices were correlated with the commodity grades: color, rate of yellow bars(including blooming flowers), rate of black heads(including black bars), and rate of stems and leaves(including bud debris). Five component content indices were correlated with the commodity grades: chlorogenic acid, isochlorogenic acid C, sweroside, loganin and the total contents of six phenolic acids. Furthermore, chlorogenic acid, loganin and the total contents of six phenolic acids showed significantly negative correlation with the main appearance characteristics, indicating that the appearance characteristics of Lonicerae Japonicae Flos can reflect its internal quality, and these 3 indices can be used as quality markers(Q-markers). The results of hierarchical cluster analysis showed that the samples of four grades were classified into four categories, and the samples with the same grades and the same categories accounted for 80.8% of the total samples, while the samples with the different grades were obviously classified into different categories. The results of PLS-DA analysis showed that the samples of different grades showed obvious intragroup aggregation and intergroup dispersion. The above results indicated that it was feasible to evaluate the traditional commodity grade of Lonicerae Japonicae Flos by the method ofquot;expert consensus of different regionsquot;. For the evaluation of traditional commodity grade of Chinese medicinal material, the samples should be representative, expert conclusions should have enough consensuses, and grade determination should be authoritative. As the crystallization of clinical experience, traditional commodity grade can scientifically reflect the internal quality of Chinese medicinal material.

The effects of the growing periods, processing methods, nutritive organs and cut parts of the herbs on the quality of Andrographis Herba have been studied, which could provide scientific basis for producing high-quality crude materials of Andrographis Herba. A quantitative analysis of multi-components by single-marker(QAMS) method was used to simultaneously determine 4 diterpene lactones of andrographolide(AD), neoandrographolide(NAD), 14-deoxyandrographolide(14-DAD), and dehydroandrographolide(DHAD) in 78 batches of Andrographis Herba samples. Visual analysis, clustering analysis and partial least squares discrimination analysis(PLS-DA) were used for data processing and mining. The growing periods of Andrographis Herba were divide into the rapid growing stage(Ⅰ), the luxuriant foliage stage(Ⅱ), the bud stage(Ⅲ), the flower stage(Ⅳ), the fruiting stage(Ⅴ) and the later fruiting stage(Ⅵ), six ones in total. The results showed that the total contents of 4 diterpene lactones(TC) kept almost constant in growing periods of Ⅰ-Ⅲ, began to fall off in growing period Ⅳ, decreased rapidly in growing period Ⅴ and reduced to minimum in growing period Ⅵ. Therefore, the best harvesting period for Andrographis Herba was the bud stage. For the processing methods, none significant difference occurred for TC between drying by the sun and drying in the shade. However, in comparison of the samples dried by the sun, the samples dried in the shade exhibited lower content of AD, nonetheless, the higher contents of DHAD and NAD, indicating that the process of drying in the shade may lead to the decomposition and transformation of AD. Therefore, when the weather conditions permitted, the method drying by the sun should be used. The distributions of AD, DHAD and TC in the different cut parts and nutritive organs were determined as follows: upper cut partsmiddle cut parts ≈ entire herbslower cut parts, leavesentire herbsstems. Furthermore, the contents of 4 diterpene lactones in leaves and herbs were much higher than those in stems. Therefore, it was suggested that the upper and middle cut parts of the herbs or the parts containing leaves should be preferred for harvesting to ensure the proportion of the leaves in Andrographis Herba.

Background High temperatures are detrimental to rice yield and quality, especially at night. Due to the predicted increases in global warming, it is imperative that crops are able to adapt to high night temperatures (HNTs) in the near future. DNA methylation is a potential mechanism for controlling gene activity and cellular phenotype under adversely environment without changing nucleotide sequence.Results Here, we reported that few CG and CHG contexts but CHH context in rice genome was strongly induced by HNT to occur cytosine methylation variation between two coisogenic rice strains with significant difference in heat tolerance. Methylation variations occurred mainly on successive cytosines in the promoter or downstream regions of transcription factors and transposon elements. In contrast to the heat-sensitive rice strain, two basal transcriptional factor TFIID subunit 11 and mediator of RNA polymerase II transcription subunit 31 were fully demethylated in the downstream 358-359 bp and 2-60 bp under HNT in the heat-tolerant strain, respectively. Various genes involved in ABA-related reactive oxygen species (ROS) equilibrium pathways, including the pentatricopeptide repeat domain gene PPR (LOC_Os07g28900) and the homeobox domain gene homeobox (LOC_Os01g19694), were induced by HNT to occur methylation variation on successive cytosines in the gene promoter regions of the heat-tolerant strain. Varidation among the typical heat-tolerant group and heat-sensitive group of rice germplasms, methylation rate of the cytosines in gene promoter region for gene PPR was higher and gene expression was suppressed in the heat-sensitive group, comparing to the heat-tolerant group.Conclusions The CHH context in rice genome was the main context type to occur cytosine methylation variation under HNT between the heat-sensitive and heat-tolerant rice strains. Methylation in the promoter regions of the genes related to abscisic acid-related oxidation and ROS scavenging contributes to rice heat tolerance. These findings provide bases to explain the molecular mechanisms behind rice heat tolerance.

Computer-based simulation models are frequently used in hydrological research and water environment decision-making. New case studies often require existing models to be adapted. Extensions may be necessary due to the peculiarities of the studied natural system. This paper introduces the object-oriented framework called FSFM designed to cope with abovementioned challenges. The modeling framework provides an easy-to-use and flexible infrastructure for the rapid development of new, reusable simulation tools by introducing dependency injection and reflection mechanism. So, it is very suitable for building new models only by substituting a few components. In addition, the CASC2D-SED-Govers model engine is developed based on the modeling framework, and it was tested on the arsenic area based on two rainfall events. It is concluded that the modeling framework in this paper is efficient for building new models in the level of fine-grained component. This paper focuses on decomposition of the model and design methods of the plug and play of the component in the modeling framework.

The traditional Chinese medicine standard decoction is prepared on the basis of the theory of traditional Chinese medicine and clinical application. With reference to the modern extraction method,the single decoction of traditional Chinese medicine is prepared by the standardized process,and the establishment of its quality standards is conducive to standardizing clinical medication. This research is to set an evaluation standard for the quality of salt-processed Psoraleae Fructus standard decoction. Twelve batches of salt-processed Psoraleae Fructus standard decoctions were prepared. The contents of psoralen and isopsoralen were determined,the transfer and extract rates were calculated,and the pH value was measured; HPLC fingerprint method was established for analysis. The results of the 12 batches of samples revealed that the transfer rates of psoralen and isopsoralen were 17. 10%-26. 40%,14. 70%-22. 70%,respectively; the extract rate was between 14. 7%-27. 0%,and the pH value was between 5. 4-6. 9. Moreover,7 common chromatographic peaks were determined based on fingerprint by using similarity evaluation system for chromatographic fingerprint of traditional Chinese medicine( 2012 A).The similarities of the 12 batches of samples were analyzed and compared,and the results showed that the similarities were all higher than0. 9. In this study,the preparation method for salt-processed Psoraleae Fructus decoction was standard,with high similarities in fingerprint. This study build a convenient and reliable method of comprehensive quality evaluation,with a high precision,stability and repeatability,which can provide a reference for the quality control of salt-processed Psoraleae Fructus dispensing granules.

To solve the problems of the poor resolution of chromatographic separation,the weak durability of the relative correction factors,and the low accuracy of content determination results in the quantitative analysis of multi-components by single-marker( QAMS) method with andrographolide as the internal reference substance in the existing research of Andrographis Herba,a new QAMS method using dehydroandrographolide as the internal reference substance was established for the first time in this study. This new method can be used to simultaneously determine four diterpene lactones,including andrographolide( A),neoandrographolide( B),14-deoxyandrographolide( C),and dehydroandrographolide( S) through the optimization of chromatographic conditions and systematic investigation of methodology. At the present HPLC chromatographic conditions,four components could be well separated( R1. 5),and the methodology validations could satisfy the requirement of quantitative analysis. The relative correction factors( RCFs) of fA/S,fB/S,fC/S were determined as 0. 65,0. 54,0. 78,respectively. The relative standard deviations( RSDs) of their RCFs ranged between 1. 3%-5. 1%,0. 25%-0. 33%,0. 070%-0. 15%,0. 070%-0. 22%,respectively with three brands of HPLC instruments,five brands of C18 column,different flow rates( 0. 9,1. 0,1. 1 m L·min~(-1)),and different column temperatures( 25,30,35 ℃),indicating good durability of the RCFs. The relative retention value( RRV) method was used to locate the chromatographic peak of the components to be determined.The RRVs of rA/S,rB/S,and rC/Swere 0. 44,0. 86,0. 97,respectively. The RSDs of the RRVs ranged between 0. 030%-1. 6% with different HPLC instruments and columns,showing accurate peak location. The present QAMS method and the external standard method( ESM)were both used to determine the contents of four diterpene lactones from Andrographis Herba( 6 batches of medicinal materials and 18 batches of cut crude drugs). The relative errors of the determined content results between two methods were less than 2. 0%. It demonstrated that there was no significant difference in content results between these two methods,indicating good accuracy of the present QAMS method. Therefore,in this study,an accurate and highly durable QAMS method using dehydroandrographolide as the internal reference substance was established for simultaneous determination of four diterpene lactones. This method could be used to effectively control the quality of Andrographis Herba and provide technical basis for the formulation of traditional Chinese medicine industry standard and improvement of the Chinese Pharmacopoeia standard of Andrographis Herba.

Polysialic acid (PSA), a carbohydrate polymer associated with the neural cell adhesion molecule (NCAM), plays an important role in the migration, differentiation and maturation of neuroblasts. Endoneuraminidase-N (Endo-N) can specifically cleave PSA from NCAM. The objective of the present study was to examine: the effect of Endo-N on characteristics of subventricular zone (SVZ)-derived neural progenitor cells (NPCs) in vitro; whether intraventricular administration of Endo-N could increase ectopic migration of SVZ-derived NPCs into 6-hydroxydopamine (6-OHDA)-lesioned striatum, and whether migrated NPCs could differentiate into neuronal and glial cells. In in vitro study, Endo-N was found to inhibit the migration of NPCs, and to enhance the differentiation of NPCs. In in vivo study, mice sequentially received injections of 6-OHDA into the right striatum, Endo-N into the right lateral ventricle, and bromodeoxyuridine (BrdU) intraperitoneally. The data showed that intraventricular injections of Endo-N disorganized the normal structure of the rostral migratory stream (RMS), and drastically increased the number of BrdU-immunoreactive (IR) cells in 6-OHDA-lesioned striatum. In addition, a number of BrdU-IR cells were double labeled for doublecortin (DCX), NeuN or glial fibrillary acidic protein (GFAP). The results suggest that interruption of neuroblast chain pathway with Endo-N facilitates ectopic migration of SVZ-derived NPCs into the lesioned striatum, and migrated NPCs can differentiate into neurons and astrocytes.

Channel simulator is an important part of the accurate evaluation of the fading characteristics of wireless channel. Efficient design and implementation of wireless channel simulator is very important for the design and verification of wireless systems. The greatest impact on the wireless communication system is a small-scale fading variation. According to the transmission characteristics, this paper analyzed the small scale fading model, the mathematical modeling simulation and hardware implementation. The measured results show that the statistical characteristics of hardware simulators output decline signal in conformity with the theoretical value, can simulate the attenuation, decline of wireless communication system, and doppler frequency shift and other transmission characteristics.

Enterovirus 71 (EV71) is the major causative agent of hand, foot and mouth disease (HFMD) in children, causing severe clinical outcomes and even death. Here, we report an important role of the highly conserved alanine residue at position 107 in the capsid protein VP1 (VP1A107) in the efficient replication of EV71. Substitutional mutations of VP1A107 significantly diminish viral growth kinetics without significant effect on viral entry, expression of viral genes and viral production. The results of mechanistic studies reveal that VP1A107 regulates the efficient cleavage of the VP0 precursor during EV71 assembly, which is required, in the next round of infection, for the transformation of the mature virion (160S) into an intermediate or A-particle (135S), a key step of virus uncoating. Furthermore, the results of molecular dynamic simulations and hydrogen-bond networks analysis of VP1A107 suggest that flexibility of the VP1 BC loop or the region surrounding the VP1107 residue directly correlates with viral infectivity. It is possible that sufficient flexibility of the region surrounding the VP1107 residue favors VP0 conformational change that is required for the efficient cleavage of VP0 as well as subsequent viral uncoating and viral replication. Taken together, our data reveal the structural role of the highly conserved VP1A107 in regulating EV71 maturation. Characterization of this novel determinant of EV71 virulence would promote the study on pathogenesis of Enteroviruses., Author summary Enterovirus 71 (EV71) causes hand, foot and mouth disease in children. In this work, we have discovered, for the first time, that the alanine residue at position 107 of the capsid protein VP1 (VP1A107), which is present in almost all EV71 strains, plays an important role in the replication of EV71, since mutation of VP1A107 significantly impairs viral growth. Detailed mechanistic studies reveal that VP1A107 determines the efficient cleavage of the VP0 precursor during EV71 assembly, and subsequent virion uncoating in the next round of viral infection. We also observed that flexibility of the VP1 BC loop or the VP1A107 region directly associates with viral infectivity. Collectively, our data suggest a structural role of the highly conserved VP1A107 residue in regulating viral maturation, which is instrumental for the viral uncoating and viral replication. Discovery of this novel determinant of EV71 virulence would promote the study on pathogenesis of Enteroviruses.

Radar chart is an important visual decision-making tool in prognostics and health management (PHM) and it can help administrators make the right judgments. We presented an improved performance degradation radar chart algorithm to enrich the visual decision-making tools in this paper. Our algorithm improves the feature extraction ability of weak fault signals from the machine and achieve visual comparison of performance degradation assessment of machine. The effectiveness of the algorithm is validated by experiments of rolling element bearings.

Radix Scutellariae (RS) is a herbal medicine with various pharmacological activities to treat inflammation, respiratory and gastrointestinal infections, etc. In this study, a rapid, sensitive and selective UPLC-ESI-MS/MS method was developed for simultaneous determination of 10 flavonoids - scutellarin, scutellarein, chrysin, wogonin, baicalein, apigenin, wogonoside, oroxylin A-7-O-glucuronide, oroxylin A and baicalin - from RS aqueous extracts in rat plasma with propyl paraben as internal standard (IS). Chromatographic separation was achieved on a C18 column using gradient elution with the mobile phase consisting of methanol and water (containing 0.1% formic acid) at a flow rate of 0.2 mL/min. The detection was performed in multiple reaction monitoring mode using electrospray ionization in negative mode. The validated method showed good linearity over a wide concentration range (r >0.9935). The intra- and interday assay variabilities were

Multi-focus image fusion means to fuse multiple source images with different focus settings into one image, so that the resulting image appears sharper. In order to extract the focused regions of the fused image efficiently, a novel pulse coupled neural network (PCNN) method for multi-focus image fusion is proposed. The registered source images are decomposed into principal components and sparse components by robust principal component analysis (RPCA) decomposition, and the important features of the sparse components are used to motivate the PCNN neurons, whose outputs detect the focused regions of the source images and integrate them to construct the final fused image. Experimental results show that the proposed scheme works better in extracting the focused regions and improving the fusion quality compared to the other existing fusion methods in terms of mutual information (MI) and

The utilization of the solar water heating system can reduce the conventional energy consumption of a building. A good inlet of the solar storage tank can enhance the thermal stratification and improve the thermal storage efficiency and discharging efficiency. Experiments were carried out to investigate the discharging performance of a rectangular storage tank with different inlet structures which were slotting-type inlet, direct inlet and shower-type inlet. This study aimed to provide guidance for the optimization of the inlet structure of water tank so that the efficiency of solar water heating system (SWHS) could be improved further. The effective discharging efficiency and effective discharging time were introduced to evaluate the performance of water tank with different inlet structures. The results showed that the slotting-type inlet exhibited the best thermal stratification and improved the discharging performance of the tank more effectively than the other two inlets. Energy saving potential of new inlet was also presented.

Experiment was carried out to investigate the influence of position of immersed coil heat exchanger inside a storage tank on the charging and discharging performance of hot water tank. Discharging efficiency and charging efficiency were introduced to evaluate the performance of hot water tank. The experiment results showed that the discharging efficiency increased with the rising of the coil position. When the flow rate was 5L/min, the discharging efficiency of the tanks with top-coil was higher 5% and 13.1% than that of the middle-coil tank and bottom-coil tank respectively. The gap of the discharging efficiency of tank with different position HX (heat exchanger) reduced with the increasing of the flow rate. However, the charging efficiency reduced with the rising of the HX position. Numerical simulation was carried out to analyze the annual performance of SWHS (solar water heating system) with different position HX by TRNSYS. The simulation results indicated that the SWHS had the lowest annual solar fraction and annual collector efficiency when the HX was on the top level of tank. The annual performance of SWHS was greatly affected by charging performance. So the solar fraction had the same trend with charging efficiency.

According to the reality of the railway oil supply chain, this paper proposes a BSC-SCOR model in five-dimension to overcome the shortcomings of the traditional BSC model, and establishes a more objective and comprehensive supply chain performance evaluation indicator system. This research uses AHP method, integration algorithm and fuzzy comprehensive evaluation to calculate the performance of the railway oil supply chain.

The paper introduces a novel algorithm to determine the optimal decomposition level in wavelet de-noising. The algorithm selects the optimal decomposition level by comparing the sparsity of wavelet coefficients at adjacent levels. The level whose wavelet coefficient has the maximum sparsity can be confirmed as the optimal decomposition level. We demonstrate experimentally that wavelet de-noising performs better using optimal decomposition level determined by our proposed algorithm than White Noise Test (WNT) method and Maximum Energy (ME) method.

Radix Aconiti Lateralis (Fuzi in Chinese, derived from the lateral roots of Aconitum Carmichaeli Debx.) is widely used for the treatment of heart failure, internal cold, arthralgia, diarrhea and edema for thousands of years. It was usually prescribed in combination with Rhizoma Zingiberis (Ganjiang in Chinese, derived from the dry rhizome of Zingiber officinale Rosc.) to decrease toxicity and increase efficacy.In order to investigate the influence of Rhizoma Zingiberis on pharmacokinetics of six Aconitum alkaloids, i.e. aconitine (AC), hypaconitine (HA), mesaconitine (MA), benzoylaconine (BAC), benzoylhypaconine (BHA) and benzoylmesaconine (BMA), in Fuzi-Ganjiang herb couple, the comparative pharmacokinetics of six Aconitum alkaloids after oral administration of Fuzi and Fuzi-Ganjiang aqueous extract was carried out.A sensitive, specific and rapid LC-MS/MS method was developed to determine the six analytes in plasma. Then the rats were randomly divided into two groups and orally administered with Fuzi and Fuzi-Ganjiang aqueous extract. At designated time points after oral administration, the concentrations of the six Aconitum alkaloids in rat plasma were determined, and main pharmacokinetic parameters were investigated using 3P97 (Practical Pharmacokinetics Program Version 1.0).Comparing with Fuzi group, both T1/2 and AUC0-t of AC and HA decreased (P0.05), while T1/2, AUC0-t and Cmax of BAC, BHA increased (P0.05) in Fuzi-Ganjiang group, which indicated that Ganjiang could promote the elimination of AC and HA and enhance the absorption of BAC, BHA and BMA.The differences of pharmacokinetics of Aconitum alkaloids in rat plasma could support those of pharmacologics and toxicity in previous reports between Fuzi and Fuzi-Ganjiang herb couple. The results might be helpful in explaining the mechanism of combination of Fuzi-Ganjiang to decrease toxicity and increase efficacy.

A specific and sensitive high performance liquid chromatography–mass spectrometric (HPLC–MS) method has been developed and validated for simultaneous determination of three anthraquinones of rhein, aloe-emodin and emodin in rat plasma after oral administration of Radix et Rhei Rhizoma extract and Dahuang Fuzi Tang. The analytes were separated on a Kromaisl ® C 18 column within a total running time of 12 min with a mobile phase of methanol:ammonium acetate (3 mM) (75:25, v/v). The calibration curves for all the anthraquinones showed good linearity in the measured range with correlation coefficient ( r ) higher than 0.9978. The precision, accuracy, recovery and stability were deemed acceptable. The method was successfully applied to the comparative pharmacokinetics study of the anthraquinones in rat plasma after oral administration of Radix et Rhei Rhizoma extract and Dahuang Fuzi Tang.

Inverted pendulum system is a non-linear，natural instability and uncertain system. As a controlled objects of control system in mechanical industry, it can be analysis and verification by different control theory and methods. The paper analysis the non-linear inverted pendulum system, then deduces sufficiency conditions of the existence of controller with state feedback. It utilizes standard digital software to get the answer. The feasibility and robustness is demonstrated by numerical examples.

The transmission of infectious diseases has been studied by mathematical methods since 1760s, among which SIR model shows its advantage in its epidemiological description of spread mechanisms. Here we established a modified SIR model with nonlinear incidence and recovery rates, to understand the influence by any government intervention and hospitalization condition variation in the spread of diseases. By analyzing the existence and stability of the equilibria, we found that the basic reproduction number [Formula: see text] is not a threshold parameter, and our model undergoes backward bifurcation when there is limited number of hospital beds. When the saturated coefficient a is set to zero, it is discovered that the model undergoes the Saddle-Node bifurcation, Hopf bifurcation, and Bogdanov-Takens bifurcation of codimension 2. The bifurcation diagram can further be drawn near the cusp type of the Bogdanov-Takens bifurcation of codimension 3 by numerical simulation. We also found a critical value of the hospital beds bc at [Formula: see text] and sufficiently small a, which suggests that the disease can be eliminated at the hospitals where the number of beds is larger than bc. The same dynamic behaviors exist even when a ≠ 0. Therefore, it can be concluded that a sufficient number of the beds is critical to control the epidemic.

Using reversed-phase high performance liquid chromatography, nine ginsenosides were simultaneously separated on an UltimateC₁₈ column with high-resolution and high purity of each chromatographic peak. Adopting the QAMS quality evaluation model for traditional Chinese medicines, ginsenoside Rb₁ was used as the internal reference substance, and the relative correction factors (RCFs) and the relative retention values (RTRs) of ginsenosides Rg₁, Re, Rf, Rb₁, Rc, Rb₂, Rb₃, Rd and 20 (S)-ginsenoside Rg₃ to ginsenoside Rb₁ were calculated individually. Through a series of methodology evaluations, and positioned by the red ginseng reference chromatograph and RTVs, nine ginsenosides in red ginseng were simultaneously assayed only by quantitative determined ginsenoside Rb₁.

This paper aims to investigate the correlation between the antioxidant activity of Prunella vulgaris and its total phenolic acids content by measuring the antioxidant activity of different sources and different organs of P. vulgaris and the total contents of protocatechuic acid, protocatechuic aldehyde, caffeic acid, salviaflaside and rosmarinic acid in these samples. Using the 50% methanol extract of P. vulgaris samples as the research object, DPPH method and HPLC method were used respectively to determine the antioxidant activities and the total contents of the above-mentioned five analytes in P. vulgaris samples. 0.5 mL of 50% methanol extract of P. vulgaris reacts with 0.1 mmol•L⁻¹ DPPH ethanol solution for 60 min, then the absorbance of the reaction solution was measured at 517 nm, scavenging rate and IC₅₀ values were calculated by the absorbance and the sample concentration for evaluating the antioxidant activity. HPLC analysis was made on a C₁₈ Epic column, with acetonitrile-0.1% formic acid aqueous solution as mobile phase (gradient elution), and the detection wavelength was set at 280 nm. The correlation between the antioxidant capacity of different habitats and different organs of P. vulgaris and the total contents of five kinds of phenolic acids was analyzed by partial least squares method. The reaction dose-response range of 50% methanol extract of P. vulgaris with 0.1 mmol•L⁻¹ DPPH ethanol solution was 0.300-1.65 g•L⁻¹. When the quantities of potocatechuic acid, protocatechuic aldehyde, caffeic acid, salviaflaside and rosmarinic acid were respectively in 0.007 84-0.980, 0.011 5-1.44, 0.008 64-1.08, 0.080 0-1.00 and 0.079 8-0.998 μg range, their quantities were in good linear relationship with the corresponding peak areas. The average recovery of 5 components were 97.76%, 96.88%, 100.3%, 102.1%, 104.5%, with RSD of 1.8%, 1.6%, 1.7%, 1.6% and 1.7%, respectively. In a certain range of crude drug quantity, the antioxidant activity of each organ of P. vulgaris and total phenolic acids content inside has a good linear correlation. Therefore, in certain quality range of crude drug, DPPH bioassay combined with HPLC content determination can be used for the quality control of P. vulgaris, as is a new method for the quality control of P. vulgaris.

Through a series of methodology investigations, we established a new method for simultaneous analysis of epimedins A, B, C, icariin and baohuoside I in Epimedii Folium by using high performance liquid chromatography (HPLC). Meanwhile, using Icariin as an internal reference substance to establish the relative correct factors and relative retention values of Epimedins A, B, C and Baohuoside I to Icariin, then using the quantitative analysis of multi-components by single-marker (QAMS) model, the five analytes can be quantitatively determined in Epimedii Folium and its processed products as well as Kanggu Zengsheng capsule only by measuring the content of icariin in the corresponding samples. All these analysis are completed in the same chromatorgraphic conditions. This paper played the part of demonstration role in the popularization and application of QAMS method established in a single herb to the proprietary Chinese medicines containing this herb.

This paper established a near-infrared spectroscopy quantitative model for simultaneous quantitative analysis of coptisine hydrochloride, dehydrocorydaline, tetrahydropalmatine, corydaline and glaucine in Corydalis Rhizoma. Firstly, the chemical values of the five components in Corydalis Rhizoma were determined by the reversed-phase high performance liquid chromatography (RP-HPLC) with UV detection. Then, the quantitative calibration model was established and optimized by fourier transformation near-infrared spectroscopy (NIRS) combined with partial least square (PLS) regression. The calibration model was evaluated by correlation coefficient (r), the root-mean-square error of calibration (RMSEC) and the root mean square of cross-validation (RMSECV) of the calibration model, as well as the correlation coefficient (r) and the root mean square of prediction (RMSEP) of prediction model. For the quantitative calibration model, the r, RMSEC and RMSECV of coptisine hydrochloride, dehydrocorydaline, tetrahydropalmatine, corydaline and glaucine were 0.941 0, 0.972 7, 0.964 3, 0.978 1, 0.979 9; 0.006 7, 0.003 5, 0.005 9, 0.002 8, 0.005 9; and 0.015, 0.011, 0.020, 0.010 and 0.022, respectively. For the prediction model, the r and RMSEP of the five components were 0.916 6, 0.942 9, 0.943 6, 0.916 7, 0.914 5; and 0.009, 0.006 6, 0.007 5, 0.006 9 and 0.011, respectively. The established near-infrared spectroscopy quantitative model is relatively stable, accurate and reliable for the simultaneous quantitative analysis of the five alkaloids, and is expected to be used for the rapid determination of the five components in crude drug of Corydalis Rhizoma.

In this paper, we aim to find eventually vanished solutions, a special class of bounded solutions which tend to 0 as t → ± ∞, to a Lienard system with a time-dependent force. Since it is not a Hamiltonian system with small perturbations, the well-known Melnikov method is not applicable to the determination of the existence of eventually vanished solutions. We use a sequence of periodically forced systems to approximate the considered system, and find their periodic solutions. Difficulties caused by the non-Hamiltonian form are overcome by applying the Schauder’s fixed point theorem. We show that the sequence of the periodic solutions has an accumulation giving an eventually vanished solution of the forced Lienard system.