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Microstructure and water-swelling mechanism of red-bed mudstone in the Xining region,Northeastern Tibetan Plateau 被引量:1
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作者 Huan Guan Yong Ren +5 位作者 Sixiang ling Xiyong Wu Tao Yu xian li Sen Wang Chunwei Sun 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第7期2537-2551,共15页
This paper examines the effect of the microstructure and electrical conductivity(EC)on the swelling ratio and pressure in red-bed mudstone sampled from arid areas in the Xining region in the northeastern Tibetan Plate... This paper examines the effect of the microstructure and electrical conductivity(EC)on the swelling ratio and pressure in red-bed mudstone sampled from arid areas in the Xining region in the northeastern Tibetan Plateau.A series of laboratory tests,including swelling experiments,X-ray diffraction(XRD),and scanning electron microscope(SEM),was carried out for mechanical and microstructural analysis.The coupled influence of the EC and microstructural parameters on the expansion ratio and pressure was investigated,and the weight coefficients were discussed by the entropy weight method.The results revealed an increasing exponential trend in EC,and the maximum swelling speed occurred at an EC of approximately 10 μS/cm.In addition,a method for predicting the expansion potential is proposed based on the microstructure,and its reliability is verified by comparing with swelling experimental results.In addition,according to the image analysis results,the ranges of the change in the clay minerals content(CMC),the fractal dimension(FD),the average diameter(AD)of pores,and the plane porosity(PP)are 23.75%-53%,1.08-1.17,7.53-22.45 mm,and 0.62%-1.25%,respectively.Moreover,mudstone swelling is negatively correlated with the plane porosity,fractal dimension and average diameter and is linearly correlated with the clay mineral content.Furthermore,the weight values prove that the microstructural characteristics,including FD,AD,and PP,are the main factors influencing the expansion properties of red-bed mudstones in the Xining region.Based on the combination of macro and micro-analyses,a quantitative analysis of the swelling process of mudstones can provide a better reference for understanding the mechanism of expansion behavior. 展开更多
关键词 MUDSTONES MICROSTRUCTURE Swelling characteristics Electrical conductivity(EC) Scanning electron microscope Water-swelling
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Tracking direct and indirect impact on technology and policy of transformative research via ego citation network
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作者 xian li Xiaojun Hu 《Journal of Data and Information Science》 CSCD 2024年第3期65-87,共23页
Purpose:The disseminating of academic knowledge to nonacademic audiences partly relies on the transition of subsequent citing papers.This study aims to investigate direct and indirect impact on technology and policy o... Purpose:The disseminating of academic knowledge to nonacademic audiences partly relies on the transition of subsequent citing papers.This study aims to investigate direct and indirect impact on technology and policy originating from transformative research based on ego citation network.Design/methodology/approach:Key Nobel Prize-winning publications(NPs)in fields of gene engineering and astrophysics are regarded as a proxy for transformative research.In this contribution,we introduce a network-structural indicator of citing patents to measure technological impact of a target article and use policy citations as a preliminary tool for policy impact.Findings:The results show that the impact on technology and policy of NPs are higher than that of their subsequent citation generations in gene engineering but not in astrophysics.Research limitations:The selection of Nobel Prizes is not balanced and the database used in this study,Dimensions,suffers from incompleteness and inaccuracy of citation links.Practical implications:Our findings provide useful clues to better understand the characteristics of transformative research in technological and policy impact.Originality/value:This study proposes a new framework to explore the direct and indirect impact on technology and policy originating from transformative research. 展开更多
关键词 Transformative research Nobel Prize winning articles Citation networks Technological impact Policy impact
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Ethylene Emission as a Potential Indicator of Fuji Apple Flavor Quality Evaluation Under Low Temperature 被引量:22
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作者 Weiyan Qi Haijing Wang +4 位作者 Zhen Zhou Peng Yang Wenbin Wu Zhemin li xian li 《Horticultural Plant Journal》 SCIE 2020年第4期231-239,共9页
Fuji apple(Malus×domestica Borkh.)is a popular fruit cultivar and occupies an important position in the fruit market due to its excellent flavor and storage quality.Ethylene emission can induce respiration,which ... Fuji apple(Malus×domestica Borkh.)is a popular fruit cultivar and occupies an important position in the fruit market due to its excellent flavor and storage quality.Ethylene emission can induce respiration,which would reduce postharvest quality and increase storage losses.In order to maintain fruit quality and extend shelf life,apples are usually stored in a low-temperature environment after harvest to reduce the formation of ethylene.Volatile aroma components are regarded as one of the most important aspects of flavor quality and a key factor for apple quality grading and customer satisfaction.Ethylene emission and its relationship with volatile aromas during low temperature,however,have not been determined.In this study,the dynamic changes of volatile aroma compounds of Fuji apples stored at 4°C were detected and analyzed for 42 days.The variation of ethylene released from Fuji apple was studied correspondingly.The results showed that ethyl butyrate,ethyl caproate,ethyl 2-methylbutyrate and 2-methylbutyl acetate were the main aroma components of Fuji apple.The change in ethylene emission and the normalized peak area of volatile aroma compounds exhibited a similar tendency that increased significantly from the 3rd day to the peak on the 14th day and then decreased;there was a positive linear correlation between them with a correlation coefficient of 0.79(P<0.05).Therefore,ethylene release can be used as a potential indicator for evaluation of volatile aroma compounds in apples.Using ethylene emission as an indicator could reduce the difficulty and complexity of volatile aroma evaluation,which could be a new non-destructive inspection choice for apple flavor quality assessment. 展开更多
关键词 APPLE AROMA flavor quality ETHYLENE correlation analysis
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Subclinical atherosclerosis in northern and southern China: the Chinese paradox 被引量:7
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作者 Jie Huang Yang-Feng Wu +8 位作者 Xiao-Qing liu Ding Ding lian-Cheng Zhao Bin Lu xian li Nathan D Wong Laurie D Dustin Stanley P Azen Robert C Detrano 《Journal of Geriatric Cardiology》 SCIE CAS CSCD 2011年第2期72-77,共6页
Background The incidence of coronary heart disease (CHD) is higher in Northern than that in Southern China, however differences in traditional CHD risk factors do not fully explain this. No study has examined the di... Background The incidence of coronary heart disease (CHD) is higher in Northern than that in Southern China, however differences in traditional CHD risk factors do not fully explain this. No study has examined the differences in subclinical atherosclerosis that may help explain the differences in incidence. This study examined these differences in subclinical atherosclerosis using coronary computed tomography (CT) for calcification between the Northern and Southern China. Methods We selected a random sample of participants in a large multi-center ongoing epidemiologic study for coronary calcium scanning in one northern city (North) (Beijing, n = 49) and in two southern cities (South) (Shanghai, n = 50, and Guangzhou, n = 50). Participants from the three field centers (mean age 67 years) underwent coronary risk factor evaluation and cardiac CT scanning for coronary calcium measurement using the Multi-Ethnic Study of Atherosclerosis scanning protocol. Results Adjusted log-transformed coronary artery calcium score in North China (Beijing) was 3.1 ±0.4 and in South China (Shanghai and Guangzhou) was 2.2 +_ 0.3 (P = 0.04). Mean calcium score for the northern city of Beijing was three times higher than that of the southern city of Guangzhou (P = 0.01) and 2.5 times higher than for the southern city of Shanghai (P = 0.03). Conclusions The extent of subclinical atherosclerosis is significantly higher in the northern city of Beijing than that in the two southern cities of Guangzhou and Shanghai, even after adjusting for standard cardiac risk factors. This finding suggests that standard risk factors do not fully explain north south differences in clinical CHD incidence. 展开更多
关键词 coronary calcium CT scanning ATHEROSCLEROSIS EPIDEMIOLOGY China
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A new triterpenoid saponin from the leaves and stems of Panax quinquefolium L. 被引量:8
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作者 Guo Yu li Yi Mei Zeng +2 位作者 He Meng xian li Jin Hui Wang 《Chinese Chemical Letters》 SCIE CAS CSCD 2009年第10期1207-1210,共4页
One new triterpcnoid saponin, quinquenoside L17 (1), was isolated from the leaves and stems of Panax quinquefolium L., and its structure was elucidated as 20-O-[(β-D-xylopyranosyl-(1-6)-O-β-D-glucopyranosy)]-6... One new triterpcnoid saponin, quinquenoside L17 (1), was isolated from the leaves and stems of Panax quinquefolium L., and its structure was elucidated as 20-O-[(β-D-xylopyranosyl-(1-6)-O-β-D-glucopyranosy)]-6-O-β-D-glucopyranosy1-dammar-24-ene- 3,6,12,20-tetraol, by the combination analysis of one-dimensional NMR and two-dimensional NMR, mass spectrometry, CD spectrum and chemical evidences. 展开更多
关键词 Panax quinquefolium L. Quinquenoside L17 Triterpenoid saponin
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Effects of IκBα and its mutants on NF-κB and p53 signaling pathways 被引量:3
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作者 xian li Da Xing +5 位作者 Ju Wang De-Bin Zhu Lan Zhang Xiao-Jia Chen Fen-Yong Sun An Hong 《World Journal of Gastroenterology》 SCIE CAS CSCD 2006年第41期6658-6664,共7页
AIM: To study the effects of IκBα and its mutants (IκBαM, IκBα3N, IκBαM44C) on NF-κB, p53 and their downstream target genes. The relationship of NF-κB, p53, and IκBα was further discussed. METHODS: pEC... AIM: To study the effects of IκBα and its mutants (IκBαM, IκBα3N, IκBαM44C) on NF-κB, p53 and their downstream target genes. The relationship of NF-κB, p53, and IκBα was further discussed. METHODS: pECFP-IκBα, pECFP-IκBαM (amino acides 1-317, Ser32, 36A), pECFP-IκBα243N (amino acides 1-243), pECFP-IκBα244C (amino acides 24±317), pEYFP-p65 and pp53-DsRed were constructed and transfected to ASTC-α-1 cells. Cells were transfected with pECFP-Cl as a control. 30 h after the transfection, location patterns of NF-κB, p53 and IκBα(IκBαM, IκBα243N, IκBα224C) were observed by a laser scanning microscope (LSM510/ConfoCor2, Zeiss). RNA extraction and reverse transcription were performed in cells transfected or co-transfected with different plasmids. Effects of IκBα and its mutants on the transprition level of NF-κB, NF-κB downstream target gene TNF-α, p53 and p53 downstream target gene Bax were observed by real time QT-PCR. In all experiments β-actin was reference. Results are expressed as the target/reference ratio of the sample divided by the target/reference ratio of the control. Different transfected cells were incubated with CCK-8 for 2 h in the incubator. Then the absorbance at 450 nm was measured by using a microplate reader. RESULTS: Cells that were transfected with p53- DsRed revealed a predominant nuclear localization. YFP-p65 mainly existed in the cytoplasm. Cells were transfected with CFP-IκBα, CFP-IκBαM, and CFP-IκBα243N respectively and revealed a predominant cytosolic localization. However, cells transfected of CFP-IκBα244C revealed a predominant nuclear localization. The rnRNA levels of p65, TNF-α, p53 and Bax in CFP-IκBα transfected cells did not change significantly, while in YFP-p65/CFP-IκBα co-transfected cells, IκBα decreased the transcription of p65 downstream gene TNF-α (2.24 ± 0.503) compared with the YFP-p65/ CFP-C1 co-transfected cells (5.08 ± 0.891) (P 〈 0.05). Phosphorylation defective IκBα (IκBαM) decreased the transcription levels of all the four genes compared with the control (P 〈 0.05). The N terminus of IκBα(IκBα243N) increased the transcription of NF-κB (1.84 ± 0.176) and TNF-α (1.51 ± 0.203) a little bit. However, the C terminus of IκBα(IκBα244C) increased the transcription of NF-κB, TNF-α, p53 and Bax significantly (8.29 ± 1.662, 14.16 ± 2.121, 10.2 ± 0.621, 3.72 ± 0.346) (P 〈 0.05). The CCK-8 experiment also showed that IκBα244C and p53 synergistically mediate apoptosis. CONCLUSIONS: IκBα and its mutants (IκBαM, IκBα243N, IκBαM244C) have different effects on NF- KB and p53 signaling pathways, according to their different structures. IκBαbounds with NF-KB and p53 in cytoplasm steadily, and inhibits both of the two signaling pathways, p53 and IκBα244C may be co-factor in inducing apoptosis. The C terminal of IκBαnhanced cell death, which suggests that it may be a pro-apoptotic protein existed in cells. 展开更多
关键词 Nuclear factor-κB Inhibitor of NF-κB alpha P53 Real-time QT-PCR
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Lentivirus-mediated short hairpin RNA interference of CENPK inhibits growth of colorectal cancer cells with overexpression of Cullin 4A 被引量:2
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作者 xian li Yi-Ru Han +6 位作者 Xuefeng Xuefeng Yong-xiang Ma Guo-Sheng Xing Zhi-Wen Yang Zhen Zhang lin Shi Xin-lin Wu 《World Journal of Gastroenterology》 SCIE CAS 2022年第37期5420-5443,共24页
BACKGROUND Colorectal cancer(CRC)is one of the most common malignant tumors worldwide.The identification of novel diagnostic and prognostic biomarkers for CRC is a key research imperative.Immunohistochemical analysis ... BACKGROUND Colorectal cancer(CRC)is one of the most common malignant tumors worldwide.The identification of novel diagnostic and prognostic biomarkers for CRC is a key research imperative.Immunohistochemical analysis has revealed high expression of centromere protein K(CENPK)in CRC.However,the role of CENPK in the progression of CRC is not well characterized.AIM To evaluate the effects of knockdown of CENPK and overexpression of Cullin 4A(CUL4A)in RKO and HCT116 cells.METHODS Human colon cancer samples were collected and tested using a human gene expression chip.We identified CENPK as a potential oncogene for CRC based on bioinformatics analysis.In vitro experiments verified the function of this gene.We investigated the expression of CENPK in RKO and HCT116 cells using quantitative polymerase chain reaction(qPCR),western blot,and flow cytometry.The effect of short hairpin RNA(shRNA)virus-infected RKO cells on tumor growth was evaluated in vivo using quantitative analysis of fluorescence imaging.To evaluate the effects of knockdown of CENPK and overexpression of CUL4A in RKO and HCT116 cells,we performed a series of in vitro experiments,using qPCR,western blot,MTT assay,and flow cytometry.RESULTS We demonstrated overexpression of CENPK in human colon cancer samples.CENPK was an independent risk factor in patients with CRC.The downstream genes FBX32,CUL4A,and Yesassociated protein isoform 1 were examined to evaluate the regulatory action of CENPK in RKO cells.Significantly delayed xenograft tumor emergence,slower growth rate,and lower final tumor weight and volume were observed in the CENPK short hairpin RNA virus infected group compared with the CENPK negative control group.The CENPK gene interference inhibited the proliferation of RKO cells in vitro and in vivo.The lentivirus-mediated shRNA interference of CENPK inhibited the proliferation of RKO and HCT116 colon cancer cells,with overexpression of the CUL4A.CONCLUSION We indicated a potential role of CENPK in promoting tumor proliferation,and it may be a novel diagnostic and prognostic biomarker for CRC. 展开更多
关键词 Colorectal cancer Centromere protein K Bioinformatics analysis Lentivirus-mediated short hairpin RNA interference Cullin 4A
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Comments on validation of conventional non-invasive fibrosis scoring systems in patients with metabolic associated fatty liver disease 被引量:1
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作者 Jian-Guo Hong Lun-Jie Yan +7 位作者 xian li Sheng-Yu Yao Peng Su Hai-Chao li Zi-Niu Ding Dong-Xu Wang Zhao-Ru Dong Tao li 《World Journal of Gastroenterology》 SCIE CAS 2022年第6期689-692,共4页
To evaluate and predict liver fibrosis in patients with nonalcoholic fatty liver disease(NAFLD),several non-invasive scoring systems were built and widely used in the progress of diagnosis and treatment,which showed g... To evaluate and predict liver fibrosis in patients with nonalcoholic fatty liver disease(NAFLD),several non-invasive scoring systems were built and widely used in the progress of diagnosis and treatment,which showed great diagnostic efficiency,such as aspartate aminotransferase to platelet ratio index,fibrosis-4 index,body mass index,aspartate aminotransferase to alanine aminotransferase ratio,diabetes score and NAFLD fibrosis score.Since the new concept of metabolic associated fatty liver disease(MAFLD)was proposed,the clinical application value of the non-invasive scoring systems mentioned above has not been assessed in MAFLD.The evaluation of the diagnostic performance of these non-invasive scoring systems will provide references for clinicians in the diagnosis of MAFLD. 展开更多
关键词 Metabolic associated fatty liver disease Prediction model Calibration Normal distribution Nonalcoholic fatty liver disease
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^(60)Co-γ射线辐射聚合制备含硅聚合物及其陶瓷转化研究
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作者 刘思阳 陈屿恒 +5 位作者 王静霞 倪茂君 杜浩田 先丽 张婧 彭朝荣 《有机硅材料》 CAS 2024年第5期13-17,共5页
采用γ-甲基丙烯酰氧基丙基三甲氧基硅烷(KH570)的乙醇溶液在^(60)Co-γ射线作用下进行辐射聚合,探讨了辐射剂量对聚合反应程度和产物分子量的影响,进一步研究了聚合产物的陶瓷化性能和裂解产物结构。结果表明,当辐射剂量为40 kGy时,KH... 采用γ-甲基丙烯酰氧基丙基三甲氧基硅烷(KH570)的乙醇溶液在^(60)Co-γ射线作用下进行辐射聚合,探讨了辐射剂量对聚合反应程度和产物分子量的影响,进一步研究了聚合产物的陶瓷化性能和裂解产物结构。结果表明,当辐射剂量为40 kGy时,KH570的聚合程度最高,制得的含硅聚合物分子量达到38.7×10^(4),多分散系数为8.24。含硅聚合物具有良好的水解活性,其固化树脂在氮气氛围下经1000℃裂解,残余质量分数为38.8%。裂解产物为具有明显光泽的纯黑色Si—O—C无定型陶瓷,其硅、氧和碳元素的含量分别为40.05%、43.65%和16.30%。 展开更多
关键词 辐射聚合 水解缩聚 陶瓷转化 硅烷
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The chemistry,distribution,and metabolic modifications of fruit flavonols 被引量:1
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作者 Mengyun Xing Yunlin Cao +2 位作者 Donald Grierson Chongde Sun xian li 《Fruit Research》 2021年第1期96-106,共11页
Fruits are considered as healthy foods because they provide a rich source of vitamins,antioxidants and other nutrients,including a range of essential bioactive flavonoid compounds.Flavonols,with diverse chemical prope... Fruits are considered as healthy foods because they provide a rich source of vitamins,antioxidants and other nutrients,including a range of essential bioactive flavonoid compounds.Flavonols,with diverse chemical properties and biological activities,are the most ubiquitous flavonoids that occur naturally in fruits and they are nutritionally important to animals and humans.Numerous investigations have emphasized that significant intake of dietary flavonols is associated with lower incidences of degenerative diseases.Here,we review current knowledge concerning the molecular structures,composition and distribution,regulation,and structural modification of fruit flavonols.In addition,we consider biotechnological approaches to enhance the levels of flavonols in plants or microorganism.An understanding of the factors determining production of flavonols in fruit crops will improve breeding programs and facilitate the production of fruits or bio-products with desirable contents of bioactive flavonols of benefit to humans. 展开更多
关键词 DISTRIBUTION CROPS BREEDING
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Randomized Algorithm for Determining Stabilizing Parameter Regions for General Delay Control Systems
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作者 Chao Yu Binh-Nguyen Le +1 位作者 xian li Qing-Guo Wang 《Journal of Intelligent Learning Systems and Applications》 2013年第2期99-107,共9页
This paper proposes a method for determining the stabilizing parameter regions for general delay control systems based on randomized sampling. A delay control system is converted into a unified state-space form. The n... This paper proposes a method for determining the stabilizing parameter regions for general delay control systems based on randomized sampling. A delay control system is converted into a unified state-space form. The numerical stability condition is developed and checked for sample points in the parameter space. These points are separated into stable and unstable regions by the decision function obtained from some learning method. The proposed method is very general and applied to a much wider range of systems than the existing methods in the literature. The proposed method is illustrated with examples. 展开更多
关键词 Stabilizing PARAMETER REGIONS Delay Control Systems RANDOMIZED Sampling LMI Stability CRITERION Support Vector MACHINES
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Feature Selection for Time Series Modeling
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作者 Qing-Guo Wang xian li Qin Qin 《Journal of Intelligent Learning Systems and Applications》 2013年第3期152-164,共13页
In machine learning, selecting useful features and rejecting redundant features is the prerequisite for better modeling and prediction. In this paper, we first study representative feature selection methods based on c... In machine learning, selecting useful features and rejecting redundant features is the prerequisite for better modeling and prediction. In this paper, we first study representative feature selection methods based on correlation analysis, and demonstrate that they do not work well for time series though they can work well for static systems. Then, theoretical analysis for linear time series is carried out to show why they fail. Based on these observations, we propose a new correlation-based feature selection method. Our main idea is that the features highly correlated with progressive response while lowly correlated with other features should be selected, and for groups of selected features with similar residuals, the one with a smaller number of features should be selected. For linear and nonlinear time series, the proposed method yields high accuracy in both feature selection and feature rejection. 展开更多
关键词 Time SERIES FEATURE SELECTION CORRELATION Analysis Modeling NONLINEAR Systems
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Application of T-Wave Alternans in Evaluation of Prognosis in Patients with Intracerebral Hemorrhage
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作者 xian li xianglin Cheng 《Yangtze Medicine》 2017年第3期127-132,共6页
Objective: To explore the application value of electrocardiograph (ECG) T-wave Alternans (TWA) anomaly in acute stage of intracerebral hemorrhage patients. Methods: We choose 1175 intracerebral hemorrhage patients who... Objective: To explore the application value of electrocardiograph (ECG) T-wave Alternans (TWA) anomaly in acute stage of intracerebral hemorrhage patients. Methods: We choose 1175 intracerebral hemorrhage patients whose conventional 12-lead ECG has TWA in our hospital from January 2011 to December 2015, 751 patients without TWA in the same period as the control group, compared the volume of intracerebral hemorrhage, bleeding site and mortality between the 2 groups. Results: In TWA group, 247 cases died, 361 cases with massive intracerebral hemorrhage, 298 cases with brain stem hemorrhage;in TWA negative group (control group), 41 cases died, 93 cases with massive brain hemorrhage, 64 cases with brain stem hemorrhage. There are statistical differences between two groups (P Conclusion: The occurrence of TWA is significantly related to the volume of bleeding, the bleeding site and mortality, and can be used as an important parameter in the prognosis of intracerebral hemorrhage. 展开更多
关键词 INTRACEREBRAL HEMORRHAGE T-WAVE ALTERNANS PROGNOSIS
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静电纺PLGA-g-PVP/I_(n)^(-)多孔抗菌纤维膜的制备及其性能研究
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作者 先丽 倪茂君 +3 位作者 张晓彬 胡椹 王静霞 彭朝荣 《化工新型材料》 CAS CSCD 北大核心 2024年第6期259-263,共5页
抗菌复合膜是修复皮肤损伤和预防皮肤感染的重要医用材料。采用^(60)Co-γ射线辐照接枝聚合法将N-乙烯基吡咯烷酮(NVP)单体接枝到聚乳酸-羟基乙酸共聚物(PLGA)上,形成聚乳酸-羟基乙酸共聚物接枝聚乙烯基吡咯烷酮(PLGA-g-PVP)链,通过碘... 抗菌复合膜是修复皮肤损伤和预防皮肤感染的重要医用材料。采用^(60)Co-γ射线辐照接枝聚合法将N-乙烯基吡咯烷酮(NVP)单体接枝到聚乳酸-羟基乙酸共聚物(PLGA)上,形成聚乳酸-羟基乙酸共聚物接枝聚乙烯基吡咯烷酮(PLGA-g-PVP)链,通过碘和聚乙烯基吡咯烷酮(PVP)的络合反应,将聚碘化物固定在PLGA表面,得到聚乳酸-羟基乙酸共聚物接枝聚乙烯基吡咯烷酮/聚碘化物(PLGA-g-PVP/I_(n)^(-))复合物。将复合物溶于二氯甲烷和N,N-二甲基甲酰胺(DMF)溶液中,采用静电纺丝技术制备了多孔抗菌纤维膜。通过凝胶渗透色谱仪、电感耦合等离子体质谱仪、傅里叶变换红外光谱仪、拉曼光谱仪、全自动物理吸附仪和扫描电子显微镜等分析手段对多孔抗菌纤维膜进行微观结构和成分分析,用金黄色葡萄球菌和大肠杆菌评价其抗菌活性。结果表明,金黄色葡萄球菌和大肠杆菌浓度为2.1×10^(4)CFU/mL和4×10^(4)CFU/mL时,该材料具有良好的抑菌效果,且对L929细胞有良好的生物相容性,细胞毒性为0级,可以作为恢复皮肤损伤和防止感染的医用材料。 展开更多
关键词 辐照接枝 静电纺丝 高聚碘 抗菌
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Subconjunctival trypsin injection for anterior chamber fibrin exudates in eyes with globe rupture following vitrectomy
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作者 Shu-Wen Lu Hao-Yu li +3 位作者 Xin-Min li Chao Ma xian li Qiu-Ming Hu 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2024年第11期2037-2044,共8页
AIM:To compare the safety and clinical outcomes of subconjunctival trypsin and dexamethasone(DEX)injections in the treatment of anterior chamber fibrin exudates in eyes with globe rupture following primary wound repai... AIM:To compare the safety and clinical outcomes of subconjunctival trypsin and dexamethasone(DEX)injections in the treatment of anterior chamber fibrin exudates in eyes with globe rupture following primary wound repair and vitrectomy.METHODS:A retrospective analysis included 42 males and 10 females(mean age 46.0±6.0y,range 34 to 58y)who underwent primary wound sutures and vitrectomy for globe rupture.Patients with pupil-covered fibrinous exudate or/and membrane in the anterior chamber were treated.On the first postoperative day,subconjunctival injections of either 5000 units(0.4 mL)of trypsin solution(n=25)or 0.5 mL(1 mg)DEX(n=27)were administered to accelerate exudate absorption.Efficacy was assessed by observing break time and partial absorption of the fibrin exudate membrane.Safety and comfort were evaluated by monitoring intraocular pressure(IOP),allergy,pain,and foreign body sensation.RESULTS:Both groups achieved 1/3 absorption of the anterior chamber fibrin exudate membrane,but the trypsin group exhibited shorter break time and partial absorption time compared to the DEX group(P<0.05).Trypsin treatment was also less irritating to patients.No adverse reactions were reported,and IOP remained stable.Visual acuity improved in both groups without statistical difference.CONCLUSION:Compared to DEX,trypsin demonstrates a shorter absorption time for the fibrin exudate membrane with a more comfortable process in treating pupil-covered fibrinous exudate or/and membrane after vitrectomy for globe rupture. 展开更多
关键词 globe rupture VITRECTOMY exudative fibrin membrane TRYPSIN dexamethasone
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地下管道抢险对轨道高架桥梁的影响研究
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作者 鲜李 罗睿 +2 位作者 姚博 戚沁菡 杨永昕 《武汉交通职业学院学报》 2024年第2期116-122,共7页
某地下管网抢险工程下穿运营的轨道线路,为研究地下管网抢险对轨道高架桥的影响。在充分对现场资料进行分析的基础上,提出了采用钢便桥方案对地下管网进行临时抢险保通,同时采用顶管方案恢复地下管网的永久服务功能。为探明地下管道抢... 某地下管网抢险工程下穿运营的轨道线路,为研究地下管网抢险对轨道高架桥的影响。在充分对现场资料进行分析的基础上,提出了采用钢便桥方案对地下管网进行临时抢险保通,同时采用顶管方案恢复地下管网的永久服务功能。为探明地下管道抢险的实施引起顶管结构、管涵围岩、城市主干路以及轨道高架桥的变形规律,通过有限元分析模型分析了其变形规律,研究结果表明:城市主干路及轨道高架桥位于顶管施工扰动区;顶管结束后,城市主干路路面变形较小,满足变形控制要求;顶管结构应力值小于规范规定的设计值;轨道高架桥的桥墩沉降差及竖向位移均满足轨道运营要求。研究成果对于顶管施工安全、轨道高架桥和城市主干路的正常运营具有重要意义,同时相关研究成果也为类似地质工况条件下分析研究提供借鉴。 展开更多
关键词 轨道高架桥 顶管法 城市主干路 地下管网临时保通 变形规律
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Granular classifier:Building traffic granules for encrypted traffic classification based on granular computing
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作者 Xuyang Jing Jingjing Zhao +2 位作者 Zheng Yan Witold Pedrycz xian li 《Digital Communications and Networks》 CSCD 2024年第5期1428-1438,共11页
Accurate classification of encrypted traffic plays an important role in network management.However,current methods confronts several problems:inability to characterize traffic that exhibits great dispersion,inability ... Accurate classification of encrypted traffic plays an important role in network management.However,current methods confronts several problems:inability to characterize traffic that exhibits great dispersion,inability to classify traffic with multi-level features,and degradation due to limited training traffic size.To address these problems,this paper proposes a traffic granularity-based cryptographic traffic classification method,called Granular Classifier(GC).In this paper,a novel Cardinality-based Constrained Fuzzy C-Means(CCFCM)clustering algorithm is proposed to address the problem caused by limited training traffic,considering the ratio of cardinality that must be linked between flows to achieve good traffic partitioning.Then,an original representation format of traffic is presented based on granular computing,named Traffic Granules(TG),to accurately describe traffic structure by catching the dispersion of different traffic features.Each granule is a compact set of similar data with a refined boundary by excluding outliers.Based on TG,GC is constructed to perform traffic classification based on multi-level features.The performance of the GC is evaluated based on real-world encrypted network traffic data.Experimental results show that the GC achieves outstanding performance for encrypted traffic classification with limited size of training traffic and keeps accurate classification in dynamic network conditions. 展开更多
关键词 Encrypted traffic classification Semi-supervised clustering Granular computing Anomaly detection
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高压旋喷型圆形复合支护桩在深厚填土质斜坡工程中的应用及探讨
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作者 鲜李 姚博 《城市地质》 2024年第1期92-96,共5页
以某市政道路项目为实例,阐述了普通圆形支护桩在深厚填土质斜坡实施过程中遇到的刚度不足及塌孔等问题,提出了一种较为稳定可靠的高压旋喷圆形复合支护桩。该结构主要由高压旋喷复合土及钢筋混凝土圆形支护桩组成,为桩土复合支护结构,... 以某市政道路项目为实例,阐述了普通圆形支护桩在深厚填土质斜坡实施过程中遇到的刚度不足及塌孔等问题,提出了一种较为稳定可靠的高压旋喷圆形复合支护桩。该结构主要由高压旋喷复合土及钢筋混凝土圆形支护桩组成,为桩土复合支护结构,由高压旋喷固结体及圆形支护桩一起承担水平土压力,具有防止垮孔,提高支护桩刚度及桩周土体物理力学指标等优点。在分析复合型支护桩受力特征基础上,通过理论推导,得到桩截面刚度提高公式。应用结果表明:采用高压旋喷型圆形复合支护桩可以有效提高桩身刚度,减小支护桩使用阶段水平位移,同时解决了桩基施工过程中垮孔问题,对填土斜坡上的支护桩有一定的普适性。 展开更多
关键词 深厚填土质斜坡 垮孔 高压旋喷复合支护桩 桩身刚度
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可注射改性羧甲基纤维素水凝胶的制备及性能 被引量:9
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作者 叶旭 李娴 +2 位作者 申月琴 邓双 张宇帆 《高分子材料科学与工程》 EI CAS CSCD 北大核心 2019年第8期75-81,共7页
对羧甲基纤维素(CMC)进行巯基接枝改性,制备了羧甲基纤维素衍生物(CMC-SH),采用溶解氧或H2O2氧化巯基(-SH)形成双硫键(-S-S-)的方法,化学交联制备了CMC-SH10、CMC-SH20和CMC-SH30系列可注射羧甲基纤维素基水凝胶,并对水凝胶的流变学性... 对羧甲基纤维素(CMC)进行巯基接枝改性,制备了羧甲基纤维素衍生物(CMC-SH),采用溶解氧或H2O2氧化巯基(-SH)形成双硫键(-S-S-)的方法,化学交联制备了CMC-SH10、CMC-SH20和CMC-SH30系列可注射羧甲基纤维素基水凝胶,并对水凝胶的流变学性能以及在37℃的磷酸盐缓冲溶液(PBS)中的溶胀率、降解行为、体外药物释放行为进行了研究。结果表明,系列CMC-SH水凝胶具有较好的流变学性能,CMC-SH30水凝胶的储能模量(G′)和屈服应力(τ)分别达到2873Pa和9328Pa;在37℃的PBS溶液中,系列水凝胶均能快速达到溶胀平衡,8h溶胀率介于22~29之间;均具有较好的稳定性,13d降解率为28%~48%;药物模型牛血清蛋白(BSA)5d的累积释放率为45%~59%,对BSA具有较好的控释能力。总体而言,前驱体浓度越高,CMC-SH水凝胶的综合性能越好,系列水凝胶均具有较好的综合性能,其中CMC-SH30水凝胶的综合性能更好,有望应用于中短期蛋白类等大分子药物传输领域。 展开更多
关键词 可注射水凝胶 羧甲基纤维素 双硫键 药物释放
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The Effect of Prophylactic Application of Noninvasive Ventilator in High Risk Patients after Cardiac Surgery and Improvement of Nursing Intervention
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作者 xian li Jing Yang Jingjing Wang 《Open Journal of Nursing》 2024年第12期617-625,共9页
Objective: To investigate the efficacy, safety and nursing improvement of noninvasive positive pressure ventilation (NPPV) in high-risk patients with acute respiratory failure after cardiac surgery. Methods: From Sept... Objective: To investigate the efficacy, safety and nursing improvement of noninvasive positive pressure ventilation (NPPV) in high-risk patients with acute respiratory failure after cardiac surgery. Methods: From September 2018 to October 2019, high-risk patients who may develop acute respiratory failure after cardiac surgery were selected and randomly divided into non-invasive ventilation group and conventional treatment group (control group). The reintubation rate, tracheotomy rate, fatality rate, 24 h intake and output, respiratory rate, arterial blood gas PaO2 and PaCO2 were compared between the two groups of patients;at the same time, the patient comfort and mask leakage after improved nursing technology were compared. Results: The preoperative and intraoperative conditions of the two groups of patients were basically similar, but the reintubation rate, tracheotomy rate, fatality rate, and respiratory rate of the patients in the preventive application of NPPV group were significantly lower than those of the control group, and the 24 h input and output and arterial blood gas PaO2 were also excellent in the control group. Conclusion: NPPV used prophylactically in high-risk patients after cardiac surgery can significantly reduce the re-intubation rate, improve patient outcomes, and is markedly more effective than the conventional treatment group. 展开更多
关键词 Noninvasive Positive Pressure Ventilation Cardiac Surgery Acute Respiratory Failure Nursing Improvement
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