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Parametric identification of time-varying systems from free vibration using intrinsic chirp component decomposition

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Acta Mechanica Sinica 2020年第1期36卷 188-205页

作者： sha Wei Shiqian Chen Xingjian Dong Zhike Peng Wenming Zhang School of Mechanics and engineering Science Shanghai UniversityShanghai200072China shanghai Institute of Applied Mathematics and Mechanics Shanghai UniversityShanghai200072China shanghai Key Laboratory of Mechanics in energy engineering Shanghai UniversityShanghai200072China State Key Laboratory of Mechanical System and Vibration Shanghai Jiao Tong UniversityShanghai200240China

Time-varying systems are applied extensively in practical applications,and their related parameter identification techniques are of great significance for structural health monitoring of time-varying *** improve the identification accuracy for time-varying systems,this study puts forward a novel parameter identification approach in the time-frequency domain using intrinsic chirp component decomposition(ICCD).ICCD is a powerful tool for signal decomposition and parameter extraction,with good signal reconstruction capability in a high-noise *** maintain good identification effects for the time-varying system in a noisy environment,the proposed method introduces a redundant Fourier model for the non-stationary signal,including instantaneous frequency(IF)and instantaneous amplitude(ia).The accuracy and effectiveness of the proposed approach are demonstrated by a single-degree-of-freedom system with three types of time-varying parameters,as well as an example of a multi-degree-of-freedom *** effects of different levels of measured noise on the identified results are also discussed in *** results show that the proposed method is very effective in tracking the smooth,periodical,and non-smooth variations of time-varying systems over the entire identification time period even when the response signal is contaminated by intense noise.

关键词： System identification Time-varying system Time-frequency domain Intrinsic chirp component decomposition

Multi-Class Classification Methods of Cost-Conscious LS-SVM for Fault Diagnosis of Blast Furnace

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Journal of Iron and Steel Research International 2011年第10期18卷 17-23,33页

作者： LIU Li-mei WANG An-na sha Mo ZHAO Feng-yun College of Information Science and engineering Northeastern University Shenyang 110819 Liaoning China

Aiming at the limitations of rapid fault diagnosis of blast furnace, a novel strategy based on cost-conscious least squares support vector machine （LS-SVM） is proposed to solve this problem. Firstly, modified discrete particle swarm optimization is applied to optimize the feature selection and the LS-SVM parameters. Secondly, cost-con- scious formula is presented for fitness function and it contains in detail training time, recognition accuracy and the feature selection. The CLS-SVM algorithm is presented to increase the performance of the LS-SVM classifier. The new method can select the best fault features in much shorter time and have fewer support vectbrs and better general- ization performance in the application of fault diagnosis of the blast furnace. Thirdly, a gradual change binary tree is established for blast furnace faults diagnosis. It is a multi-class classification method based on center-of-gravity formula distance of cluster. A gradual change classification percentage ia used to select sample randomly. The proposed new metbod raises the sped of diagnosis, optimizes the classifieation scraraey and has good generalization ability for fault diagnosis of the application of blast furnace.

关键词： blast furnace fault diagnosis eosc-conscious LS-SVM multi-class classification

蛛网膜下腔出血患者外周血NLR、LMR、PLR和SII值变化的临床意义

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脑与神经疾病杂志 2024年第6期32卷 345-349页

作者：揭伟刘微波刘莎杨伟四川省科学城医院神经外科绵阳621900 四川省科学城医院康复科绵阳621900

目的分析动脉瘤性蛛网膜下腔出血(aSAH)对血液学参数的影响及其与患者临床状态和短期预后的关系。方法分析2019年3月至2022年5月于四川省科学城医院神经外科治疗的62例颅内动脉瘤(ia)破裂急性期患者和55例正常对照组。采用流式细胞术... 详细信息

目的分析动脉瘤性蛛网膜下腔出血(aSAH)对血液学参数的影响及其与患者临床状态和短期预后的关系。方法分析2019年3月至2022年5月于四川省科学城医院神经外科治疗的62例颅内动脉瘤(ia)破裂急性期患者和55例正常对照组。采用流式细胞术分析两组患者外周血中白细胞(WBC)与淋巴细胞(LC)计数的变化,计算中性粒细胞/淋巴细胞比(NLR)、淋巴细胞/单核细胞比(LMR)、血小板/淋巴细胞比(PLR)和全身免疫-炎症指数(SII),并分析血液学参数与患者临床状况和短期预后的关系。结果与正常对照组相比,ia破裂组WBC、中性粒细胞(Ns)计数、NLR以及SII均明显升高,而LC计数和LMR降低。此外相比于临床状态恢复良好的患者,临床状态较差的患者LC计数明显降低,而NLR、PLR和SII值明显升高。格拉斯哥昏迷评分法(GCS)评分较低的患者CD3+、CD4-、CD8-细胞比例减少。此外,LC计数降低和PLR升高与较差的短期预后相关。结论 ia破裂后会导致全身免疫和炎症反应,LC计数、NLR、PLR和SII值可以作为临床状态及预后的标志物。

关键词：颅内动脉瘤中性粒细胞/淋巴细胞比淋巴细胞/单核细胞比血小板/淋巴细胞比全身免疫-炎症指数预后

COVID-19 impact on the liver

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World Journal of Clinical Cases 2021年第16期9卷 3814-3825页

作者： Liliana Baroiu Caterina Dumitru Alina iancu Ana-Cristina Leșe Miruna Drăgănescu Nicușor Baroiu Lucreția Anghel Clinical Medical Department Faculty of Medicine and Pharmacy“Dunarea de Jos”University of GalatiGalati 800008Romania Pharmaceutical Sciences Department Faculty of Medicine and Pharmacy“Dunarea de Jos”University of GalatiGalati 800008Romania Department of Morphological and Functional Sciences Faculty of Medicine and Pharmacy“Dunarea de Jos”University of GalatiGalati 800008Romania Design Department Faculty of Visual Arts and Design“George Enescu”National University of ArtsIasi 700451Romania Department of Manufacturing engineering Faculty of Engineering“Dunarea de Jos”University of GalatiGalati 800008Romania

The coronavirus disease 2019(COVID-19)pandemic imposed arestructuring of global health systems by rethinking spaces used for the care of these patients and the additions of intensive care,infectious diseases and pneumology *** paper provides evidence on the presence of severe acute respiratory syndrome coronavirus 2 in hepatocytes and its direct cytopathic activity,as well as the degree of liver damage due to drug toxicity,inflammation and hypoxia in COVID-19.A review of clinical trials has quantified liver damage through both pathology and biochemistry ***,we briefly present the results of a study conducted in our clinic on 849 patients admitted for COVID-19 treatment,of which 31 patients had pre-existing chronic liver disease and 388 patients had values above the normal limit for alanine aminotransferase,aspartate aminotransferase,and total *** was observed that patients with abnormal liver tests were significantly statistically older,had more comorbidities and had a higher percentage of unfavourable evolution(death or transfer to intensive care).The conclusion of this paper is that the main causes of liver damage are direct viral aggression,coagulation dysfunction and endothelial damage,and patients with impaired liver function develop more severe forms of COVID-19 which requires special care by a multidisciplinary team that includes a hepatologist.

关键词： COVID-19 Liver injury Cytopathic effect Hyper-inflammatory reaction Drug toxicity Biochemical changes

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温敏型纳米复合材料的研制及驱油性能研究

现代化工 2024年第7期44卷 186-192页

作者：陈思齐郑学成樊维林小莎周雪峰西南石油大学化学化工学院四川成都610500 西南石油大学油气田应用化学四川省重点实验室四川成都610500 南充电子信息产业技术研究院四川南充637131

为提高纳米流体驱对油藏的适用性,满足高效开采的需求,设计了一种对温度能动态响应的纳米材料。将温敏性单体异丙基丙烯酰胺(NIPAm)和亲水单体衣康酸(ia)接枝在纳米SiO_(2)表面制备了温敏型纳米复合材料NIPAm/ia/SiO_(2)。通过红外光谱... 详细信息

为提高纳米流体驱对油藏的适用性,满足高效开采的需求,设计了一种对温度能动态响应的纳米材料。将温敏性单体异丙基丙烯酰胺(NIPAm)和亲水单体衣康酸(ia)接枝在纳米SiO_(2)表面制备了温敏型纳米复合材料NIPAm/ia/SiO_(2)。通过红外光谱、动态光扫射等表征手段研究了NIPAm/ia/SiO_(2)的化学结构、热稳定性、形貌及粒径。结果表明,NIPAm/ia/SiO_(2)具有良好的分散性和热稳定性(初始分解温度为310℃),中值粒径为264 nm。当环境温度低于低临界溶液温度(LCST)时,NIPAm/ia/SiO_(2)呈现亲水性。温敏型纳米流体的润湿作用使岩石表面亲水性增强、毛细管力增大,NIPAm/ia/SiO_(2)提高采收率主要是通过渗吸作用完成;当温度高于LCST时,NIPAm/ia/SiO_(2)呈现两亲性,此时岩石表面趋于中性润湿,从而提高了油水两相的流动性,使孔喉中的油更容易被注入流体驱替。

关键词：温度响应纳米复合材料提高采收率地层温度低临界溶液温度

Fine-scale analysis reveals a potential influence of forest management on the spatial genetic structure of eremanthus erythropappus

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Journal of Forestry Research 2021年第4期32卷 1567-1578页

作者： Lucas Fernandes Rocha Natália Ribeiro de Paula Dulcinéia De Carvalho Department of Forest Science Federal University of Lavras(UFLA)Av.Doutor Sylvio Menicucci1001 Aquental SolLavrasMinas Gerais State 37200-000Brazil Department of Forest Science College of Agricultural Sciences(FCA/UNESP)São Paulo State UniversityAv.Universitária3780Altos do ParaísoBotucatuSão Paulo State 18610-034Brazil

Forest management may have significant effects on forest connectivity and natural population *** old-growth single trees may also change natural patterns of genetic variation and spatial genetic *** study evaluated the impacts of forest management using a silvicultural system of seed trees on the genetic diversity and spatial genetic structure of eremanthus erythropappus(DC.)MacLeish.A complete survey of 275 trees on four plots was undertaken out to compare the genetic variation of a managed stand with an unmanaged *** genotyped all adult and juvenile individuals 60 months after the management and compared the genetic diversity and the spatial genetic structure *** diversity was considered high because of an efficient gene flow between *** were no genetic differences between stands and no evidence of *** clustering identified a single population(K=1),indicating no genetic differentiation between managed and unmanaged *** and juvenile individuals of the unmanaged stand were more geographically structured than individuals from the managed *** was a tendency of coancestry among juveniles at the first class of distance of the managed stand,suggesting a drift of genetic structure possibly caused by *** early responses to management on genetic diversity and stand structure is a first step to ensuring the effectiveness of conservation practices of tree *** sustainability of forest management of *** on genetic diversity,and more accurately,on spatial genetic structure needs evaluation over time to promote effective conservation of the population size and genetic variability.

关键词： Genetic diversity Microsatellite markers Gene flow Silvicultural management Brazilian Cerrado

Targeting hepatic ceruloplasmin mitigates nonalcoholic steatohepatitis by modulating bile acid metabolism

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Journal of Molecular Cell Biology 2023年第9期15卷 53-68页

作者： Quanxin Jiang Ning Wang Sĳia Lu Jie Xiong Yanmei Yuan Junli Liu Suzhen Chen shanghai Diabetes Institute Department of Endocrinology and MetabolismShanghai Sixth People’s Hospital Affiliated to Shanghai Jiao Tong University School of MedicineShanghai 200233China

Nonalcoholic steatohepatitis(NASH)is a condition that progresses from nonalcoholic fatty liver disease(NAFLD)and is characterized by hepatic fat accumulation,inflammation,and *** has the potential to develop into cirrhosis and liver cancer,and currently no effective pharmacological treatment is *** this study,we investigate the therapeutic potential of targeting ceruloplasmin(Cp),a copper-containing protein predominantly secreted by hepatocytes,for treating *** result show that hepatic Cp is remarkedly upregulated in individuals with NASH and the mouse NASH ***-specific Cp ablation effectively attenuates the onset of dietary-induced NASH by decreasing lipid accumulation,curbing inflammation,mitigating fibrosis,and ameliorating liver *** employing transcriptomics and metabolomics approaches,we have discovered that hepatic deletion of Cp brings about remarkable restoration of bile acid(BA)metabolism during *** deletion of Cp effectively remodels BA metabolism by upregulating Cyp7a1 and Cyp8b1,which subsequently leads to enhanced BA synthesis and notable alterations in BA *** conclusion,our studies elucidate the crucial involvement of Cp in NASH,highlighting its significance as a promising therapeutic target for the treatment of this disease.

关键词： ceruloplasmin nonalcoholic steatohepatitis bile acid inflammation fibrosis

Ground motion prediction equations based on shallow crustal earthquakes in Georgia and the surrounding Caucasus

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earthquake Science 2022年第6期35卷 497-509页

作者： Jorjiashvili Nato Shengelia ia Godoladze Tea Gunia Irakli Akubardia Dimitri Institute of earth Sciences and National Seismic Monitoring Center Ilia State UniversityTbilisi 0177Georgia

Strong ground motions caused by earthquakes with magnitudes ranging from 3.5 to 6.9 and hypocentral distances of up to 300km were recorded by local broadband stations and three-component accelerograms within Georgia’s enhanced digital seismic *** data mixing is particularly effective in areas where strong ground motion data are *** data were used to produce models based on ground-motion prediction equations(GMPes),one benefit of which is that they take into consideration information from waveforms across a wide range of *** this study,models were developed to predict ground motions for peak ground acceleration and 5%-damped pseudo-absolute-acceleration spectra for periods between 0.01 and 10 ***-period ground motions decayed faster than long-period motions,though decay was still in the order of approximately 1/*** mechanisms and local soil conditions greatly influence *** spectral acceleration(SA)of thrust faults was higher than that for either strike-slip or normal faults but the influence of strike-slip faulting on SA was slightly greater than that for normal *** soils also caused significantly more amplification than rocky sites.

关键词： strong ground motion peak ground acceleration spectral acceleration shallow earthquake

Research on controllable alkaline soil degradation of 5-substituted chlorsulfuron

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Chinese Chemical Letters 2018年第6期29卷 945-948页

作者： shaa Zhou Xuewen Hua Wei Wei Minggui Chen Yucheng Gu sha Zhou Haibin Song Zhengming Li State Key Laboratory of elemento-Organic Chemistry Collaborative Innovation Centre of Chemical Science and Engineering (Tianjin) College of Chemistry Nankai University Tianjin 300071 China College of Agriculture Liaocheng University Liaocheng 252000 China Syngenta Jealott's Hill International Research Centre Bracknell RG42 6EY United Kingdom

Sulfonylurea（SU） has become one class of the most important herbicides worldwide due to their ultralow application rate and mammalian toxicity. Recently application licenses of 3 classical SU herbicides chlorsulfuron, metsulfuron-methyl and ethametsulfuron were suspended due to their undesirable long persistence which is incompatible with the particular rotation planting system in China. Our previous study has discovered that electron-donating groups, especially dimethylamino and diethylamino substituents, on the 5 th position of the benzene ring in chlorsulfuron, greatly accelerated its degradation rate in an acidic soil（p H 5.41）. Owing to the natural slower degradation of SUs in alkaline soil,dimethylamino and diethylamino substituted chlorsulfuron ia and Ib were further studied in an alkaline soil（p H 8.46） with chlorsulfuron as a control. The experimental data indicated that the half-life of degradation（DT50） of ia was 3.36 days while Ib was 6.25 days which amounted to 30 and 15 folds faster than chlorsulfuron（DT5084.53 days）, respectively. The research confirmed that our newly-designed structures ia and Ib can hasten their degradation rate in alkaline soil as well as in acidic soil. This structural modification of the classical SU provided an opportunity to control the degradation rate to reduce their impact on relevant environment and ecology.

关键词： Chlorsulfuron Sulfonylurea herbicides Soil degradation Alkaline soil DT50