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An Analytic Model of Galactic Winds and Mass Outflows

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Chinese Journal of Astronomy and Astrophysics 2005年第4期5卷 327-346页

作者： Cheng-Gang Shu Hou-Jun Mo Shu-de Mao Joint Center for Astrophysics Shanghai Normal University Shanghai 200234 Shanghai Astronomical Observatory Chinese Academy of Sciences Shanghai 200030 Max-Planck-Institut fuer Astrophysik Karl-Schwarzschild-Strasse 1 Postfach 1317 D-85741 Garching Germany Astronomy department University of Massachusetts Amherst MA 01003 USA Jodrell Bank Observatory Univ. of Manchester Macclesfield Cheshire SK11 9DL UK

Galactic winds and mass outflows are observed both in nearby starburst galaxies and in high-redshiff star-forming galaxies. We develop a simple analytic model to understand the observed superwind phenomenon with a discussion of the model uncertainties. Our model is built upon the model of McKee ＆ Ostriker for the interstellar medium. It allows one to predict how properties of a superwind,such as wind velocity and mass outflow rate, are related to properties of its starforming host galaxy, such as size, gas density and star formation rate. The model predicts a threshold of star formation rate density for the generation of observable galactic winds. Galaxies with more concentrated star formation activities produce superwinds with higher velocities. The predicted mass outflow rates are comparable to （or slightly larger than） the corresponding star formation rates. We apply our model to both local starburst galaxies and high-redshift Lyman break galaxies,and find its predictions to be in good agreement with current observations. Our model is simple and so can be easily incorporated into numerical simulations and semi-analytical models of galaxy formation.

关键词： galaxies starburst - galaxies ISM - galaxies kinematics and dynamics - galaxies formation and evolution

Extracting hand articulations from monocular depth images using curvature scale space descriptors

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Frontiers of Information Technology & Electronic Engineering 2016年第1期17卷 41-54页

作者： Shao-fan WANG Chun LI de-hui KONG Bao-cai YIN Beijing Key Laboratory of Multimedia and Intelligent Software Technology College of Metropolitan Transportation Beijing University of Technology Beijing 100124 China School of Software Technology Dalian University of Technology Dalian 116024 China Collaborative Innovation Center of Electric Vehicles in Beijing Beijing 100081 China

We propose a framework of hand articulation detection from a monocular depth image using curvature scale space(CSS) descriptors. We extract the hand contour from an input depth image, and obtain the fingertips and finger-valleys of the contour using the local extrema of a modified CSS map of the contour. Then we recover the undetected fingertips according to the local change of depths of points in the interior of the contour. Compared with traditional appearance-based approaches using either angle detectors or convex hull detectors, the modified CSS descriptor extracts the fingertips and finger-valleys more precisely since it is more robust to noisy or corrupted data;moreover, the local extrema of depths recover the fingertips of bending fingers well while traditional appearance-based approaches hardly work without matching models of hands. Experimental results show that our method captures the hand articulations more precisely compared with three state-of-the-art appearance-based approaches.

关键词： Curvature scale space (CSS), Hand articulation, Convex hull, Hand contour

A New Route for the Synthesis of N-Substituted Diketopiperazine derivatives

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Chinese Chemical Letters 2006年第4期17卷 469-472页

作者： Xi GONG Xiao Xiao YANG de Xin WANG Institute of Materia Medica Chinese Academy of Medical Sciences ＆ Peking Union Medical College Beijing 100050

Eight N-substituted diketopiperazines （DKPs） were synthesized by solid-phase protocols. The introduction of iminodiacetic acid （Ida） and followed another a-amino acid residue as the precursor of DKP framework made... 详细信息

关键词： Diketopiperazine iminodiacetic acid solid-phase synthesis.

Influence of NaCI on Cathode Performance of Solid Oxide Fuel Cells

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Chemical Research in Chinese Universities 2013年第4期29卷 747-750页

作者： LIU Run-ru WANG de-jun LENG Jing College of Science College of Continuing Education Changchun University Changchun 130022 P. R. China College of Basic Sciences Changchun University of Technology Changchun 130012 P. R. China

degradation induced by sodium chloride in air was investigated for （La0.8Sr0.2）0.98MnO3（LSM） and ***3（LSCF） cathodes in solid oxide fuel cells（SOFC）. Cell performance was measured by volatilizing NaC1 to be supplied to the cathode at a constant current density of 200 mA/em2 for up to 100 h. At 800℃, an exposure of the cathode to 30 mg/L NaC1 caused negligible degradation of LSM at least for 100 h. Slight change in the composition of the cathode materials was observed which may imply the gradual degradation of cell performance for the long-term. In addition, cell performance degradation was compared between 700℃ and 900℃, being poi- soned by 30 mg/L NaCI. degradation was negligible for LSM cathode, while LSCF cathode showed slightly poor to-lerance at 700℃ due to the decomposition of the cathode material. Further studies should be done to clarify the long-term influence of NaCI on cathode performance.

关键词： NaC1 degradation Cathode Solid oxide fuel cell(SOFC)

Does gemcitabine-based combination therapy improve the prognosis of unresectable pancreatic cancer?

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World Journal of Gastroenterology 2012年第35期18卷 4944-4958页

作者： Chen Sun Daniel Ansari Roland Andersson de-Quan Wu department of Surgery Second Af-filiated Hospital of Harbin Medical University Harbin 150086Heilongjiang Province China department ofSurgery Clinical Sciences Lund Lund University Sk~ne Univer-sity Hospital SE-22185 Lurid Sweden

AIM:To assess whether gemcitabine-based combination therapy improves the prognosis of unresectable pancreatic cancer compared with gemcitabine treatment ***:A quantitative up-to-date meta-analysis was undertaken to investigate the efficacy of gemcitabine-based combination treatment compared with gemcitabine monotherapy in locally advanced or metastatic pancreatic *** was limited to highquality randomized clinical ***:Twenty-six studies were included in the present analysis,with a total of 8808 patients *** studies were divided into four subgroups based on the different kinds of cytotoxic agents,including platinum,fluoropyrimidine,camptothecin and targeted *** treated with gemcitabine monotherapy had significantly lower objective response rate [risk ratio(RR),0.72;95% confidence interval(CI):0.63-0.83;P de 3-4 toxicities:including vomiting(RR,0.75;95%CI:0.62-0.89;P = 0.001),diarrhea(RR,0.66;95%CI:0.49-0.89;P = 0.006),neutropenia(RR,0.88;95%CI:0.72-1.06;P = 0.18),anemia(RR,0.96;95%CI:0.82-1.12;P = 0.60),and thrombocytopenia(RR,0.76;95%CI:0.60-0.97;P = 0.03) compared with gemcitabine combination ***:Gemcitabine combination therapy provides a modest improvement of survival,but is associated with more toxicity compared with gemcitabine monotherapy.

关键词：联合治疗胰腺癌晚期基础预后细胞毒性单克隆抗体血小板减少

dermic-derived fibroblasts for the study of amyotrophic lateral sclerosis

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Neural Regeneration Research 2020年第11期15卷 2043-2044页

作者： Javier Riancho Sara Arozamena Adolfo Lopez de Munain Service of Neurology Hospital Sierrallana-IDIVALTorrelavegaSpain department of Medicine and Psychiatry University of CantabriaSantanderSpain Centro de Investigacion en Red de Enfermedades Neurodegenerativas Instituto Carlos IIIMadridSpain Neurosciences Area Biodonostia Research InstituteService of NeurologyHospital Universitario DonostiaDepartment of NeurosciencesSchool of Medicine and NurseryUniversity of the Basque CountrySan SebastianSpain

Among neurodegenerative diseases,amyotrophic lateral sclerosis(ALS)is the most frequent one involving motor neurons(MNs).ALS incidence varies throughout the world ranging from 0.7 to 4 cases per 100,000 habitants and year(Riancho et al.,2016).This disease,which currently lacks an effective therapy,is characterized by a variable combination of upper and lower MN degeneration,leading to progressive muscle wasting which usually results in a terminal respiratory failure within 3 years after symptom onset(Zufiria et al.,2016).A small proportion of ALS cases show familial *** are related to mutations in specific causative genes(Cr9ORF72,TARDBP,FUS,SOD1 and others)which directly determine disease onset in *** contrast,more than 90 percent of cases are considered to be sporadic,in which generally unknown environmental and internal factors interact with genetic predisposing factors finally leading to disease(Riancho et al.,2018).From a histopathological point of view,ALS is characterized by MN damage and *** from ALS sporadic and most of familial patients exhibit prominent transactive response DNA-binding protein 43(TDP-43)cytoplasmic aggregates which are considered as the“pathological hallmark”of the disease,excepting those related to SOD1 and FUS mutations(Zufiria et al.,2016).TDP-43 is a DNA/RNA binding protein encoded by the TARDBP gene that controls the expression of many different genes.

关键词： al. amyotrophic degeneration

Using LSA and text segmentation to improve automatic Chinese dialogue text summarization

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第1期8卷 79-87页

作者： LIU Chuan-han WANG Yong-cheng ZHENG Fei LIU de-rong department of Computer Science and Engineering Shanghai Jiao Tong University Shanghai 200030 China Center for Biomimetic Sensing and Control Research Institute of Intelligent Machines Chinese Academy of Sciences Hefei 230031 China

Automatic Chinese text summarization for dialogue style is a relatively new research area. In this paper, Latent Semantic Analysis (LSA) is first used to extract semantic knowledge from a given document, all question paragraphs are identified, an automatic text segmentation approach analogous to TextTiling is exploited to improve the precision of correlating question paragraphs and answer paragraphs, and finally some “important” sentences are extracted from the generic content and the ques-tion-answer pairs to generate a complete summary. Experimental results showed that our approach is highly efficient and improves significantly the coherence of the summary while not compromising informativeness.

关键词：汉语对话自动文本摘要隐含语义分析文本分析对话方式

New Abundant Exact Solutions For Kundu Equation

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Acta Mathematicae Applicatae Sinica 2015年第3期31卷 729-734页

作者： Jun LIU Zheng-de DAI Gui MU Xi LIU College of Mathematics and Information Science Qujing Normal University School of Mathematics and Statistics Yunnan University School of Information Science and Engineering Yunnan University

In this paper, the higher order NLS equation with cubic-quintic nonlinear terms is studied, new abundant solitary solutions with traveling-wave envelope of this equation are obtained with the aid of a generalized auxi... 详细信息

关键词： Kundu equation generalized auxiliary equation method solitary wave

Ultra-compact on-chip metaline-based 1.3/1.6 μm wavelength demultiplexer

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Photonics Research 2019年第3期7卷 359-362页

作者： YULONG FAN XAVIER LE ROUX ANATOLE LUPU ANDRé de LUSTRAC Centre de Nanosciences et de Nanotechnologies CNRS Université Paris-Sud Université Paris-Saclay Université Paris Lumières Univ Paris Nanterre

In this paper, we report an experimental demonstration of enabling technology exploiting resonant properties of plasmonic nanoparticles, for the realization of wavelength-sensitive ultra-minituarized(4 μm× 4 μm) optical metadevices. To this end, the example of a 1.3/1.6 μm wavelength demultiplexer is considered. Its technological implementation is based on the integration of gold cut-wire-based metalines on the top of a silicon-on-insulator waveguide. The plasmonic metalines modify locally the effective index of the Si waveguide and thus allow for the implementation of wavelength-dependent optical pathways. The 1.3/1.6 μm wavelength separation with extinction ratio between two demultiplexers' channels reaching up to 20 dB is experimentally demonstrated. The considered approach, which can be readily adapted to different types of material planar lightwave circuit platforms and nanoresonators, is suited for the implementation of a generic family of wavelength-sensitive guided-wave optical metadevices.

关键词： experimental optical lightwave is Its can dB be