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Parameter identification and synchronization of spatiotemporal.chaos in an uncertain Gray-Scott system

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Science China(Physics,Mechanics & Astronomy) 2008年第11期51卷 1638-1646页

作者： l.l.ng l. Yi GUO ZhiAn Col.ege of Physics and El.ctronic Technol.gy Liaoning Normal UniversityDalian 116029China Department of Mathematics and Physics Dalian Jiaotong UniversityDalian 116028China

The zero-asymptotic property of sl.ding variabl.s in discrete systems is extended to a continuous one and appl.ed to partial.differential.equations which describe spatiotemporal.chaos. A method of chaos synchronization and parameter identifi-cation is proposed. The synchronization control.ers and the parameter recognizers are designed. The uncertain Gray-Scott system is taken as an exampl. to verify the effectiveness of the method. Simul.tion resul.s show that the identification vari-abl.s in the parameter recognizers may take the pl.ce of the unknown parameters in both target and response systems. Gl.bal.synchronization of the two spatio-temporal.chaotic systems with uncertain parameters may be real.zed quickl. after control.ers are added.

关键词： spatiotemporal chaos sl.ding variabl. parameter identification synchronization uncertain Gray-Scott system

Pros and cons of col.noscopy in management of acute l.wer gastrointestinal.bl.eding

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Worl. Journal.of Gastroenterol.gy 2012年第11期18卷 1185-1190页

作者： Dekey Y l.ewa l.sa l.Strate Division of Hospital.and Special.y Medicine Department of MedicinePuget Sound Health Care System Seattle DivisionSeattleWA 98108United States Division of Gastroenterol.gy Department of MedicineUniversity of Washington School of Medicine and Harborview Medical CenterSeattleWA 98104United States

Acute l.wer gastrointestinal.bl.eding （l.IB） is a frequent gastrointestinal.cause of hospital.zation, particul.rl. in the el.erl., and its incidence appears to be on the rise. Endoscopic and radiographic measures are avail.bl. for the eval.ation and treatment of l.IB incl.ding fl.xibl. sigmoidoscopy, col.noscopy, angiography, radionucl.de scintigraphy and mul.i detector row computed tomography. Al.hough no modal.ty has emerged as the gol. standard in the management of l.IB, col.noscopy is the current preferred initial.test for the majority of the patients presenting with hema- tochezia fel. to be from a col.n source. Col.noscopy has the abil.ty to diagnose al. sources of bl.eding from the col.n and, unl.ke the radiol.gic modal.ties, does not require active bl.eding at the time of the examination. In addition, therapeutic interventions such as cautery and endocl.ps can be appl.ed to achieve hemoo stasis and prevent recurrent bl.eding. Studies suggest that col.noscopy, particul.rl. when performed earl.in the hospital.zation, can decrease hospital.l.ngth of stay, rebl.eding and the need for surgery. However, resul.s from avail.bl. smal. trial. are confl.cting and l.rger, mul.icenter studies are needed. Compared to other management options, col.noscopy is a safe procedure with compl.cations reported in l.ss than 2% of patients, incl.ding those undergoing urgent examinations. The requirement of bowel.preparation （typical.y 4 or more l.ters of pol.ethyl.ne gl.col., the l.gistical.compl.xity of coordinating after hours col.noscopy, and the l.w preval.nce of stigmata of hemorrhage compl.cate the use of col.noscopy for l.IB, particul.rl. in urgent situations. This review discusses the above advantages and disadvantages of col.noscopy in the management of acute l.wer gastrointestinal.bl.eding in further detail.

关键词： Col.noscopy Acute l.wer gastrointestinal.l.eding Management Diagnostic yiel. Therapeuticintervention Outcomes Col.n preparation Stigmataof hemorrhage

Airborne Observations of Cl.ud Condensation Nucl.i Spectra and Aerosol. over East Inner Mongol.a

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Advances in Atmospheric Sciences 2017年第8期34卷 1003-1016页

作者： Jiefan YANG Hengchi l.I Yuhuan l. l.boratory of Cl.ud-Precipitation Physics and Severe Storms Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100081 China Col.aborative Innovation Center on Forecast and Eval.ation of Meteorol.gical.Disasters Nanjing University of lnformation Science and Technology Nanjing 210044 China Wuqing Meteorol.gical.Observatory of Tianjin Tianjin 301700 China

A set of vertical.profil.s of aerosol.number concentrations, size distributions and cl.ud condensation nucl.i（CCN）spectra was observed using a passive cl.ud and aerosol.spectrometer（PCASP） and cl.ud condensation nucl.i counter, over the Tongl.ao area, East Inner Mongol.a, China. The resul.s showed that the average aerosol.number concentration in this region was much l.wer than that in heavil. pol.uted areas. Monthl. average aerosol.number concentrations within the boundary l.yer reached a maximum in May and a minimum in September, and the variations in CCN number concentrations at different supersaturations showed the same trend. The parameters c and k of the empirical.function N = c S^kwere 539 and1.477 under cl.an conditions, and their counterparts under pol.uted conditions were 1615 and 1.42. Measurements from the airborne probe mounted on a Yun-12（Y12） aircraft, together with Hybrid Singl.-Particl. l.grangian Integrated Trajectory model.backward trajectories indicated that the air mass from the south of Tongl.ao contained a high concentration of aerosol.particl.s（1000–2500 cm^（-3）） in the middl. and l.wer parts of the troposphere. Moreover, detail.d intercomparison of data obtained on two days in 2010 indicated that the activation efficiency in terms of the ratio of NCCNto N_a（aerosol. measured from PCASP） was 0.74（0.4 supersaturations） when the air mass mainl. came from south of Tongl.ao, and this val.e increased to 0.83 on the rel.tivel. cl.aner day. Thus, l.ng-range transport of anthropogenic pol.utants from heavil. pol.uted mega cities,such as Beijing and Tianjin, may resul. in sl.ghtl. decreasing activation efficiencies.

关键词： CCN aerosol.size distribution aircraft observation

The Effect of the Subtropical.Jet on the Rainfal. over Southern China in January 2008

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Advances in Atmospheric Sciences 2014年第3期31卷 543-550页

作者： ZUO Qunjie GAO Shouting l. Daren l.boratory of Cl.ud-Precipitation Physics and Severe Storms Institute of Atmospheric Physics Chinese Academy of Sciences Key l.boratory of Middl. Atmosphere and Gl.bal.Environment Observation Institute of Atmospheric Physics Chinese Academy of Sciences State Key l.boratory of Severe Weather Chinese Academy of Meteorological Sciences

ABSTRACT The third precipitation episode of China＇s great snowstorms of 2008 was anal.zed using station observations and ECMWF six-hourl. data. The variation of the shape of the upper-l.vel.subtropical.jet pl.yed an important rol. in the rainfal. over south- ern China. With the eastward movement of the trough, the jet shape changed from two straight jets to a til.ing jet over China and then it moved southward. With these variations, the south-north movement of ascending fl.w and precipitation area over southern China occurred.

关键词： upper-l.vel.subtropical.jet transverse circul.tion ageostrophic wind snowstorms

Treatment of infl.mmatory bowel.disease:A review of medical.therapy

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Worl. Journal.of Gastroenterol.gy 2008年第3期14卷 354-377页

作者： Patricia l.Kozuch Stephen B Hanauer Division of Gastroenterol.gy and Hepatol.gy Department of Medicine Thomas Jefferson University Hospital Philadelphia PA United States University of Chicago Hospital. Department of Medicine Section of Gastroenterology and Nutrition Chicago IL 60637 United States

Crohn’s disease (CD) and ul.erative col.tis (UC) are chronic infl.mmatory diseases of the gastrointestinal.tract. Whil. a cure remains el.sive, both can be treated with medications that induce and maintain remission. With the recent advent of therapies that inhibit tumor necrosis factor (TNF) al.ha the overl.p in medical.therapies for UC and CD has become greater. Al.hough 5-ASA agents have been a mainstay in the treatment of both CD and UC, the data for their efficacy in patients with CD, particul.rl. as maintenance therapy, are equivocal. Antibiotics may have a l.mited rol. in the treatment of col.nic CD. Steroids continue to be the first choice to treat active disease not responsive to other more conservative therapy; non- systemic steroids such as oral.and rectal.budesonide for il.al.and right-sided CD and distal.UC respectivel. are al.o effective in mil.-moderate disease. 6-mercaptopurine (6-MP) and its prodrug azathioprine are steroid-sparing immunomodul.tors effective in the maintenance of remission of both CD and UC, whil. methotrexate may be used in both induction and maintenance of CD. Infl.ximab and adal.mumab are anti-TNF agents approved in the US and Europe for the treatment of Crohn's disease, and infl.ximab is al.o approved for the treatment of UC.

关键词： Infl.mmatory bowel.disease Crohn's disease Ul.erative col.tis Medical.therapy

穴位贴敷配合梅花针叩刺治疗周围性面瘫的疗效观察

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上海针灸杂志 2024年第9期43卷 945-950页

作者：王润芳吕翔裴志勇临汾市人民医院临汾041000

目的观察穴位贴敷配合梅花针叩刺治疗周围性面瘫的临床疗效。方法将90例周围性面瘫患者随机分为治疗组和对照组,每组45例。治疗组采用穴位贴敷配合梅花针叩刺治疗,对照组采用单纯穴位贴敷治疗。观察两组治疗前后面神经兴奋阈值、面神经... 详细信息

目的观察穴位贴敷配合梅花针叩刺治疗周围性面瘫的临床疗效。方法将90例周围性面瘫患者随机分为治疗组和对照组,每组45例。治疗组采用穴位贴敷配合梅花针叩刺治疗,对照组采用单纯穴位贴敷治疗。观察两组治疗前后面神经兴奋阈值、面神经功能指数(facial.nerve functional.index,FNFI)、面部表情肌(额肌、降口角肌及降下唇肌)弹性、各项实验室指标[血清胶质细胞源性神经营养因子(gl.al.cel.-l.ne-derived neurotrophic factor,GDNF)、神经生长因子(nerve growth factor,NGF)、总抗氧化能力(total.antioxidant capacity,TAOC)水平]及面部残疾指数(facial.disabil.ty,FDI)中躯体功能(FDI physical.function,FDIp)评分和社会功能(FDI social.l.fe function,FDIs)评分的变化情况,比较两组临床疗效。结果治疗组总有效率为91.1%,明显高于对照组的73.3%(P<0.05)。两组治疗后面神经兴奋阈值和FDIs评分均较同组治疗前显著降低,FNFI、各项面部表情肌弹性、各项实验室指标及FDIp评分均显著升高,差异均具有统计学意义(P<0.05)。治疗组治疗后面神经兴奋阈值和FDIs评分均明显低于对照组,FNFI、各项面部表情肌弹性、各项实验室指标及FDIp评分均明显高于对照组,差异均具有统计学意义(P<0.05)。结论穴位贴敷配合梅花针叩刺治疗周围性面瘫疗效确切,可有效改善面神经兴奋阈值及面神经功能,提高面部表情肌弹性,升高血清GDNF、NGF及TAOC水平。

关键词：穴位贴敷法梅花针疗法面神经麻痹周围性面瘫叩刺面神经兴奋阈值面神经功能总抗氧化能力

Al.ohol.induced al.erations of the hepatocyte cytoskel.ton

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Worl. Journal.of Gastroenterol.gy 2010年第11期16卷 1358-1365页

作者： Bl.the D Shepard Pamel. l.Tuma Department of Biol.gy The Catholic University of America

The hepatocyte cytoskel.ton consists of three fi l.mentous networks: microtubul.s, actin microfi l.ments and keratin intermediate fil.ments. Because of the abundance of the proteins that comprise each system and the central.rol. each network pl.ys in a variety of cel.ul.r processes, the three fi l.ment systems have been the focus of a host of studies aimed at understanding the progression of al.ohol.induced l.ver injury. In this review, we wil. briefl. discuss the hepatic organization of each cytoskel.tal.network and highl.ght some components of each system. We wil. al.o describe what is known about ethanol.induced changes in the dynamics and distributions of each cytoskel.tal.system and discuss what is known about changes in protein expression l.vel. and post-transl.tional.modifi cations. Final.y, we wil. describe the possibl. consequences of these cytoskel.tal.al.erations on hepatocyte function and how they might contribute to the progression of l.ver disease.

关键词： Ethanol Hepatotoxicity Tubul.n Actin Keratin

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鲑鱼泌乳素cDNA的分子克隆和序列分析

Acta Genetica Sinica 1989年第5期16卷 374-380页

作者：宋诗铎 K. Y. Trinh C. l. Hew 天津医学院第二附属医院加拿大多伦多大学临床生化和生化系

从太平洋切奴克鲑鱼的垂体制备cDNA文库。按照鲑鱼泌乳素的部分蛋白质序列所提供的信息合成寡聚脱氧核苷酸探针。用探针筛查泌乳素基因,识别出一个阳性克隆PRl.10。该克隆的硷基序列已被测出。PRl.10的总长为1.1kb,编码了含有211个氨基... 详细信息

从太平洋切奴克鲑鱼的垂体制备cDNA文库。按照鲑鱼泌乳素的部分蛋白质序列所提供的信息合成寡聚脱氧核苷酸探针。用探针筛查泌乳素基因,识别出一个阳性克隆PRl.10。该克隆的硷基序列已被测出。PRl.10的总长为1.1kb,编码了含有211个氨基酸组成的泌乳素前体,其中包括了编码23个氨基酸的信号肽序列和编码188个氨基酸的成熟泌乳素序列。

关键词：鲑鱼泌乳素 cDNA 序列分析

Mol.cul.r mechanisms control.ing seed set in cereal.crop species under stress and non-stress conditions

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Journal.of Integrative Agricul.ure 2018年第5期17卷 965-974页

作者： l. Hui-yong Thomas l.bberstedt Cereal.Crops Research Institute Henan Academy of Agricultural Sciences Department of Agronomy Iowa State University

Maximizing seed yiel. is the ul.imate breeding goal.in important cereal.crop species. Seed set is a key devel.pmental.stage in the process of seed formation, which determines grain number, seed mass, and real.zed yiel. potential. and can be severel. affected by abiotic and biotic stresses. However, seed set can al.o be substantial.y reduced by genetic factors even under optimal.fertil.zation conditions. The underl.ing mol.cul.r genetic mechanisms are stil. obscure. In this review, we el.cidate the process of seed set of cereal.crop species in detail. incl.ding devel.pment of fl.ral.structures, formation of viabl. gametes, doubl. fertil.zation, seed devel.pment, and abortion. We discuss how genetic and non-genetic factors affect seed set in different devel.pment stages. Final.y, we wil. propose novel.strategies to study genetic mechanisms control.ing seed set and expl.it genetic resources to improve seed set in cereal.crop species.

关键词： maize seed set mol.cul.r mechanism