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Analyses of risk factors and prognosis for new-onset atrial fibrillation in elderly patients after dual-chamber pacemaker implantation

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Journal of Geriatric Cardiology 2018年第10期15卷 628-633页

作者： xiao-Li CHEN Xue-Jun ren Zhuo LIANG Zhi-hong HAN Tao ZHANG Zhi LUO Department of Cardiology Beijing Geriatric HospitalBeijingChina Department of Cardiology Beijing Anzhen HospitalCapital Medical UniversityBeijingChina

Objective To retrospectively identify risk factors and the prognosis for new-onset atrial fibrillation (AF)after implantation of dual-chamber pacemakers in elderly *** Consecutive patients aged >65years who underwent their first implantation of a dual-chamber permanent pacemaker in Beijing Anzhen Hospital from October 2013to May 2016were *** complete program- ming and follow-up data were ***-up end points included new-onset AF and major adverse cardiovascular and cerebrovascular *** Altogether,322patients were enrolled,with new-onset AF observed in 79(24.5%)during their *** analysis identified four independent predictors of new-onset AF in elderly patients after pacemaker implantation:hypertension (HR =3.040, 95%CI:1.09-3.05,P =0.00),age (HR =1.966,95%CI:1.57-3.68,P =0.01);left atrial enlargement (HR =1.645,95%CI:1.05-1.25,P = 0.03);high ventricular pacing rate (HR =1.137,95%CI:1.01-1.06,P =0.01).Univariable analysis indicated that the CHA2DS2-VASc score was also a risk factor for AF (HR =1.368,95%CI:1.178-1.589,P =0.002),whereas multivariable regression analysis did not. Kaplan-Meier survival analysis showed that the risk for ischemic stroke was significantly higher in the new-onset AF group than in the non-AF group (P <0.05).Conclusion Hypertension,age,left atrial enlargement,and high ventricular pacing rate were independent predictors of new-onset AF in elderly patients after implantation of a permanent ***-onset AF increased the risk for ischemic stroke.

关键词： Atrial fibrillation Dual-chamber pacemaker Elderly Ischernic stroke

Modeling deterministic echo state network with loop reservoir

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Journal of Zhejiang University-Science C(Computers and Electronics) 2012年第9期13卷 689-701页

作者： xiao-chuan SUN hong-yan CUI ren-ping LIU Jian-ya CHEN Yun-jie LIU Beijing Key Laboratory of Network System Architecture and Convergence Beijing University of Posts and Telecommunications Beijing 100876China ICT Centre Commonwealth Scientific and lndustrial Research OrganizationSydney 1710Austraiia

Echo state network (ESN), which efficiently models nonlinear dynamic systems, has been proposed as a special form of recurrent neural network. However, most of the proposed ESNs consist of complex reservoir structures, leading to excessive computational cost. Recently, minimum complexity ESNs were proposed and proved to exhibit high performance and low computational cost. In this paper, we propose a simple deterministic ESN with a loop reservoir, i.e., an ESN with an adjacent-feedback loop reservoir. The novel reservoir is constructed by introducing regular adjacent feedback based on the simplest loop reservoir. Only a single free parameter is tuned, which considerably simplifies the ESN construction. The combination of a simplified reservoir and fewer free parameters provides superior prediction performance. In the benchmark datasets and real-world tasks, our scheme obtains higher prediction accuracy with relatively low complexity, compared to the classic ESN and the minimum complexity ESN. Furthermore, we prove that all the linear ESNs with the simplest loop reservoir possess the same memory capacity, arbitrarily converging to the optimal value.

关键词： Echo state networks Loop reservoir structure Memory capacity

Experimental Study on Vortex-Induced Vibration of Rough Risers Coupling with Interference Effect in Tandem Arrangement

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China Ocean Engineering 2024年第3期38卷 394-407页

作者： HU Ze-bo LIU Zhen LI Peng GUO Hai-yan ren xiao-hui HOU Hao HAO Lian-hong College of Civil Engineering and Architecture Shandong University of Science and TechnologyQingdao 266590China Qingdao Key Laboratory of Marine Civil Engineering Materials and Structures Qingdao 266590China College of Engineering Ocean University of ChinaQingdao 266100China

In order to study the response law of vortex-induced vibration(VIV)of marine risers under the combined action of roughness and interference effects,and to reveal the coupling mechanism of roughness and interference effects on the riser,a VIV experiment of rough risers in tandem arrangement was conducted in a wave−current combined *** experiment characterized the risers’roughness by arranging different specifications of attachments on the surface of the *** rough risers with different roughness and smooth risers were arranged in tandem arrangement,with the rough risers arranged *** experimental results indicate that the suppression of the attachments on the downstream risers’vibration are more significant both in the CF and IL directions as the reduced velocity *** the downstream riser,the amplitude response of rough riser is more significantly weakened compared with the smooth one at high reduced *** the upstream risers,changes in the roughness and spacing ratio have an impact on their‘lock-in’*** the roughness of downstream risers is relatively large(0.1300)and the spacing between risers is small(S/D=4.0),the reduced velocity range of‘lock-in’region in the CF direction of upstream risers is obviously expanded,and the displacement in the‘lock-in’region is severer.

关键词： marine riser vortex-induced vibration tandem arrangement roughness interference effect

Optical monitoring and intra-day variabilities of BL Lac Objects OJ 287

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Research in Astronomy and Astrophysics 2021年第6期21卷 263-275页

作者： Yu-Hai Yuan Jun-Hui Fan hong Wu Jing-Meng Hao Wei-Rong Huang xiao-Lan Liu hong-ren Huang Center for Astrophysics Guangzhou UniversityGuangzhou 510006China Astronomy Science and Technology Research Laboratory of Department of Education of Guangdong Province Guangzhou 510006China Key Laboratory for Astronomical Observation and Technology of Guangzhou Guangzhou 510006China Key Laboratory of Optical Astronomy National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China

Using the 1.26 m National Astronomical Observatory-Guangzhou University Infrared/Optical Telescope(NGT),we monitor one BL Lac object,OJ *** this source,we obtain 15094 gri observations(4900 at g band,5184 at r band and 5010 at i band)in 155 nights from 2014 December 13 to 2019 *** on the upper observations,we obtain the following results.(1)The total variation amplitude is~2.3 mag.(2)There are intra-day variabilities(IDVs).The IDV timescales(△T)are in the range from 7.69 min(Δm=0.06±0.02 mag)to 371.09 min(Δm=0.26±0.04 mag).(3)There are strong correlations betweenΔT andΔm,△m=(2.91±0.66)×10^(-4)ΔT+(0.08±0.009),with r=0.52,p=5.33×10^(-5).(4)There are intra-day periods in this source,with the period P≈94 min on 2017 December *** we supplement the observations from the literature,we can obtain that the long-term period is about 12.02±0.41 yr.(5)The spectral properties of OJ 287 show the bluer-when-brighter behavior,whatever state the source is at.

关键词： quasars:individual(OJ 287) photometry

Dietary curcumin alleviates intestinal damage induced by ochratoxin A in juvenile grass carp(Ctenopharyngodon idella):Necroptosis and inflammatory responses

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Animal Nutrition 2024年第3期18卷 119-132页

作者： Piao Zhao Wei Dan Jiang Pei Wu Yang Liu hong Mei ren xiao Wan Jin Lin Feng xiao Qiu Zhou Animal Nutrition Institute Sichuan Agricultural UniversityChengdu 611130SichuanChina Fish Nutrition and Safety Production University Key Laboratory of Sichuan Province Sichuan Agricultural UniversityChengdu 611130SichuanChina Key Laboratory of Animal Disease-Resistance Nutrition Ministry of EducationMinistry of Agriculture and Rural AffairsKey Laboratory of Sichuan ProvinceSichuan611130China

Ochratoxin A(OTA)is one of the most common pollutants in aquatic *** a first line of defense,intestinal barriers could be utilized against OTA in order to prevent *** product supplementation is one of the most popular strategies to alleviate toxicity induced by mycotoxins,but there is a lack of knowledge about how it functions in the teleost *** this study,720 juvenile grass carp of about 11 g were selected and four treatment groups(control group,OTA group,curcumin[Cur]group,and OTA+Cur group)were set up to conduct a 60-day growth *** the test,the growth performance and intestinal health related indexes of grass carp were *** addition of dietary Cur could have the following main results:(1)inhibit absorption and promote efflux transporters mRNA expression,reducing the residuals of OTA,(2)decrease oxidative stress by reducing oxidative damage and enhancing the expression of antioxidant enzymes,(3)promote mitochondrial fusion proteins to inhibit the expression of mitotic proteins and mitochondrial autophagy proteins and enhance mitochondrial function,(4)reduce necroptosis-related gene expression through inhibiting the tumor necrotic factor receptor-interacting protein kinase/mixed lineage kinase domain-like pathway,(5)reduce the expression of pro-inflammatory factors by inhibiting the Toll-like receptor 4/nuclear factor-κB signaling pathway to alleviate the intestinal inflammatory *** summary,the results suggested that Cur could alleviate OTA-induced intestinal damage by enhancing antioxidant capacity and mitochondrial function as well as reducing necroptosis and inflammation in the grass carp *** study provided a theoretical basis and production implications for dietary Cur that could improve growth performance and alleviate the intestinal damage induced by OTA in fish.

关键词： Curcumin Ochratoxin A Grass carp growth performance Mid-intestine mitochondria function Necroptosis

Exploring choices of early nutritional support for patients with sepsis based on changes in intestinal microecology

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World Journal of Gastroenterology 2023年第13期29卷 2034-2049页

作者： xiao-Juan Yang xiao-hong Wang Ming-Yue Yang hong-Yan ren Hui Chen xiao-Ya Zhang Qin-Fu Liu Ge Yang Yi Yang xiao-Jun Yang Department of Critical Care Medicine General Hospital of Ningxia Medical UniversityYinchuan 750004Ningxia Hui Autonomous RegionChina School of Clinical Medicine Ningxia Medical UniversityYinchuan 750004Ningxia Hui Autonomous RegionChina Department of Emergency Medicine Affiliated Hospital of Jining Medical UniversityJining 272030Shandong ProvinceChina Shanghai Mobio Biomedical Technology Co. Ltd.Shanghai 201318China Department of Critical Care Medicine Southeast University School of MedicineZhongda HospitalSchool of MedicineSoutheast UniversityNanjing 210009Jiangsu ProvinceChina

BACKGROUND Sepsis exacerbates intestinal microecological disorders leading to poor *** modalities of nutritional support can improve nutrition,immunity,and intestinal *** To identify the optimal modality of early nutritional support for patients with sepsis from the perspective of intestinal *** Thirty patients with sepsis admitted to the intensive care unit of the General Hospital of Ningxia Medical University,China,between 2019 and 2021 with indications for nutritional support,were randomly assigned to one of three different modalities of nutritional support for a total of 5 d:Total enteral nutrition(TEN group),total parenteral nutrition(TPN group),and supplemental parenteral nutrition(SPN group).Blood and stool specimens were collected before and after nutritional support,and changes in gut microbiota,short-chain fatty acids(SCFAs),and immune and nutritional indicators were detected and compared among the three *** In comparison with before nutritional support,the three groups after nutritional support presented:(1)Differences in the gut bacteria(Enterococcus increased in the TEN group,Campylobacter decreased in the TPN group,and Dialister decreased in the SPN group;all Prent trends in SCFAs(the TEN group showed improvement except for Caproic acid,the TPN group showed improvement only for acetic and propionic acid,and the SPN group showed a decreasing trend);(3)significant improvement of the nutritional and immunological indicators in the TEN and SPN groups,while only immunoglobulin G improved in the TPN group(all P<0.05);and(4)a significant correlation was found between the gut bacteria,SCFAs,and nutritional and immunological indicators(all P<0.05).CONCLUSION TEN is recommended as the preferred mode of early nutritional support in sepsis based on clinical nutritional and immunological indicators,as well as changes in intestinal microecology.

关键词： Sepsis Nutritional support Intestinal microecology Short-chain fatty acids Nutritional and immunological indicators Total enteral nutrition Total parenteral nutrition Supplemental parenteral nutrition

Comparison of the Kinetics of 1-Hexene Metathesis by Ruthenium Carbene Catalysts

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Chinese Chemical Letters 2006年第7期17卷 988-990页

作者： Chen Xi BAI Wen Zhen ZHANG ren HE Yan hong SUN xiao Ping CAI Research Institute of Jilin Petrochemical Company Ltd. Petrochina Jilin 132021 State Key Laboratory of Fine Chemicals Dalian University of Technology Dalian 116012

A kinetic study of two ruthenium carbene catalysts, （PCy3）2Cl2Ru=CHPh 1 （Grubbs catalyst） and a new catalyst [1,3-bis（2,6-dimethylphenyl）4,5-dihydroimidazol-2-ylidene]（PPh3）（Cl）2Ru-CHPh 3, were conducted in metathesis of 1-hexene. The kinetic behavior of these catalysts at 40, 50, 60 and 70℃ was compared. Complex 3 has the more active catalytic effect at temperatures 40-70℃.

关键词： Ruthenium carbene metathesis.

DEFORMATION OF COPOLYMER MICELLES INDUCED BY AMPHIPHILIC DIMER PARTICLES

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Chinese Journal of Polymer Science 2012年第2期30卷 164-172页

作者： xiao-chun Qin Chun-lai ren National Laboratory of Solid State Microstructures Nanjing UniversityNanjing 210093China

Combining self-consistent-field theory and density-functional theory, we systematically study the deformation of copolymer micelles induced by the presence of amphiphilic dimer particles. Due to the amphiphilic nature, dimer particles tend to accumulate onto the interface of the copolymer micelle. With increasing concentration of the symmetric dimer particles, which are made of two identical spherical particles, the micelle deforms from the initial sphere to ellipse, dumbbell, and finally separates into two micelles. Furthermore, asymmetric dimer particles, composed by two particles with different sizes, are considered to investigate the influence of geometry of dimer particles on the deformation of the micelle. It is found that the micelle inclines to deform into dumbbell due to the additional curvature originating in the gathering of asymmetric dimer particles onto the interface of the micelle. The present study on the deformation of micelles is useful to understand the possible shape variation in the course of cell division/fusion.

关键词： Dimer particle Copolymer micelle Deformation Self consistent field theory Density function theory.

Endogenous Hydrogen Peroxide Plays a Positive Role in the Upregulation of Heme Oxygenase and Acclimation to Oxidative Stress in Wheat Seedling Leaves

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Journal of Integrative Plant Biology 2009年第10期51卷 951-960页

作者： xiao-Yue Chen xiao Ding Sheng Xu ren Wang Wei Xuan Ze-Yu Cao Jian Chen hong-hong Wu Mao-Bing Ye Wen-Biao Shen College of Life Sciences Cooperative Demonstration Laboratory of Centrifuge Technique Nanjing Agricultural University and Beckman Coulter Ltd. Co. Nanjing Agricultural University Nanjing 210095 China Institute of Botany Jiangsu Province and the Chinese Academy of Sciences (Mem. Sun Yat-Sen) Jiangsu Province Key Laboratory for Plant Ex-situ Conservation Nanjing 210014 China

Pretreatment of lower H2O2 doses （0.05, 0.5 and 5 mM） for 24 h was able to dose-dependently attenuate lipid peroxidation in wheat seedling leaves mediated by further oxidative damage elicited by higher dose of H2O2 （150 mM） for 6 h, with 0.5 mM H2O2 being the most effective concentrations. Further results illustrated that 0.5 mM H2O2 pretreatment triggered the biphasic production of H2O2 during a 24 h period. We also noticed that only peak Ⅰ （0.25 h） rather than peak Ⅱ （4 h） was approximately consistent with the enhancement of heme oxygenase （HO） activity, HO-1 gene expression. Meanwhile, enhanced superoxide dismutase （SOD） activity, Mn-SOD and Cu, Zn-SOD transcripts might be a potential source of peak Ⅰ of endogenous H2O2. Further results confirmed that 0.5 mM H2O2 treatment for 0.5 h was able to upregulate HO gene expression, which was detected by enzyme activity determination, semi-quantitative reverse transcription-polymerase chain reaction and western blotting. Meanwhile, the application of N,N＇-dimethylthiourea, a trap for endogenous H2O2, not only blocked the upregulation of HO, but also reversed the corresponding oxidation attenuation. Together, the above results suggest that endogenous H2O2 production （peak Ⅰ） plays a positive role in the induction of HO by enhancing its mRNA level and protein expression, thus leading to the acclimation to oxidative stress.

关键词： acclimation to oxidative stress endogenous hydrogen peroxide heme oxygenase signal transduction Triticum