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Decomposing the host galaxy from high-z QSOs using principal component analysis

Research in Astronomy and Astrophysics 2019年第10期19卷 17-26页

作者： Wei He yi-ping wang National Astronomical Observatories Chinese Academy of Sciences Beijing 100101 China School of Astronomy and Space Science University of Chinese Academy of Sciences Beijing 100049 China

High resolution deep imaging from space and adaptive optics techniques with large ground-based facilities have enabled studies examining faint host galaxies of high redshift quasi-stellar objects (QSOs). However, the related image processing techniques, especially for a precise point-spread function (PSF) reconstruction and characterization of the host galaxy light profiles, have yet to be optimized. We present here the scientific performance of a principal component analysis (PCA) based PSF subtraction of the central bright point source of high redshift QSO images, as well as further characterization of the host galaxy profile by directly fitting a Sèrsic model to the residual image using the Markov Chain Monte Carlo (MCMC) algorithm. With a set of reference PSF star images which represent interleaving exposures between the QSO imaging, we can create an orthogonal basis of eigen-images and restore the PSF of QSO images by projecting the QSO images onto the basis. In this way, we can quantify the modes in which the PSF varies with time by a basis function that characterizes the temporal variations of the reference star as well as the QSO images. To verify the algorithm, we performed a simulation and applied this method to one of the high-z QSO targets from Mechtley et al. We demonstrate that the PCA-based PSF subtraction and further modeling of the galaxy’s light profile using MCMC fitting would sufficiently remove the effects from central dominating point sources, and improve characterization ability for the host galaxies of high-z QSOs to the background noise level which is much better than previous two-component fitting procedures.

关键词： quasars general-galaxies active-galaxies high-redshift-methods data analysis

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Measuring orbital angular momentum of vortex beams in optomechanics

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Frontiers of physics 2021年第3期16卷 177-183页

作者： Zhucheng Zhang Jiancheng Pei yi-ping wang Xiaoguang wang Zhejiang Institute of Modern Physics Department of PhysicsZhejiang UniversityHangzhou310027China College of Science Northwest A&F UniversityYangling712100China Graduate School of China Academy of Engineering Physics Beijing100193China

Measuring the orbital angular momentum(OAM)of vortex beams,including the magnitude and the sign,has great application prospects due to its theoretically unbounded and orthogonal ***,the sign-distinguishable OAM measurement in optomechanics is proposed,which is achieved by monitoring the shift of the transmission spectrum of the probe field in a double Laguerre-Gaussian(LG)rotational-cavity *** with the traditional single LG rotational cavity,an asymmetric optomechanically induced transparency window can occur in our ***,the position of the resonance valley has a strong correlation with the magnitude and sign of *** originally comes from the fact that the effective detuning of the cavity mode from the driving field can vary with the magnitude and sign of OAM,which causes the spectral shift to be directional for different signs of *** scheme solves the shortcoming of the inability to distinguish the sign of OAM in optomechanics,and works well for high-order vortex beams with topological charge value±45,which is a significant improvement for measuring OAM based on the cavity optomechanical system.

关键词： orbital angular momentum optomechanically induced transparency Laguerre-Gaussian rotational-cavity system optomechanics

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Metabolite sensing and signaling in cell metabolism

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Signal Transduction and Targeted Therapy 2018年第1期3卷 43-51页

作者： yi-ping wang Qun-ying Lei Cancer Institute Fudan University Cancer Hospital and Cancer Metabolism LaboratoryInstitutes of Biomedical SciencesFudan University200032 ShanghaiPeople’s Republic of China

Metabolite sensing is one of the most fundamental biological *** evolution,multilayered mechanisms developed to sense fluctuations in a wide spectrum of metabolites,including nutrients,to coordinate cellular metabolism and biological *** date,AMPK and mTOR signaling are among the best-understood metabolite-sensing and signaling ***,we propose a sensor-transducer-effector model to describe known mechanisms of metabolite sensing and *** define a metabolite sensor by its specificity,dynamicity,and *** group the actions of metabolite sensing into three different modes:metabolite sensor-mediated signaling,metabolite-sensing module,and sensing by *** these modes of action,we provide a systematic view of how cells sense sugars,lipids,amino acids,and metabolic *** the future perspective,we suggest a systematic screen of metabolite-sensing macromolecules,high-throughput discovery of biomacromolecule-metabolite interactomes,and functional metabolomics to advance our knowledge of metabolite sensing and *** importantly,targeting metabolite sensing holds great promise in therapeutic intervention of metabolic diseases and in improving healthy aging.

关键词： holds coordinate sugar

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Metabolic recoding of epigenetics in cancer

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Cancer Communications 2018年第1期38卷 272-279页

作者： yi-ping wang Qun-ying Lei Cancer Institute Fudan University Cancer Hospital and Cancer Metabolism LaboratoryInstitutes of Biomedical SciencesFudan UniversityShanghai 200032P.R.China

Dysregulation of metabolism allows tumor cells to generate needed building blocks as well as to modulate epigenetic marks to support cancer initiation and ***-induced metabolic changes alter the epigenetic landscape,especially modifications on histones and DNA,thereby promoting malignant transformation,adaptation to inadequate nutrition,and *** advances in cancer metabolism shed light on how aberrations in metabolites and metabolic enzymes modify epigenetic *** metabolism-induced recoding of epigenetics in cancer depends strongly on nutrient availability for tumor *** this review,we focus on metabolic remodeling of epigenetics in cancer and examine potential mechanisms by which cancer cells integrate nutritional inputs into epigenetic modification.

关键词： Cancer metabolism Epigenetics Metabolites Histone modification DNA methylation Cancer microenvironment Nutrient availability

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Ported wall extension hydraulics

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Water Science and Engineering 2021年第1期14卷 65-71页

作者： Fei-dong Zheng ping-yi wang Jian-feng An Yun Li College of River and Ocean Engineering Chongqing Jiaotong UniversityChongqing 400074China National Engineering Technology Research Center for Inland Waterway Regulation Chongqing 400074China State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering Nanjing 210029China

Ported wall extensions are important hydraulic structures used to reduce crosscurrents in upper approaches to *** effect of such extensions located upstream of a solid guard wall on flow characteristics depends on many factors,including geometric and hydraulic *** this study,the hydraulic performance of ported wall extensions was experimentally investigated in terms of the permeability coefficient,expanding angle,extension length,and flow *** results demonstrate that the dimensionless maximum transverse velocity is closely related to the permeability coefficient,expanding angle,and flow *** contrast,the dimensionless eddy length mainly depends on the permeability coefficient,expanding angle,and extension ***,the optimum permeability coefficient increases with the expanding angle or flow depth,and it is approximately constant for different extension *** results have the potential to provide direct guidance for the design of effective ported wall extensions in upper approaches to locks.

关键词： Ported wall extension Permeability coefficient Transverse velocity Eddy length Navigation safety

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Intestinal histoplasmosis in immunocompetent adults

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World Journal of Gastroenterology 2016年第15期22卷 4027-4033页

作者： Lin-Lin Zhu Jin wang Zi-Jing wang yi-ping wang Jin-Lin Yang Department of Gastroenterology West China Hospital of Sichuan University Gastroenterology Kanazawa University Graduate School of Medical Science

AIM: To present a retrospective analysis of clinical and endoscopic features of 4 cases of immunocompetent hosts with intestinal histoplasmosis(IH).METHODS: Four immunocompetent adults were diagnosed with IH between October 2005 and March 2015 at West China Hospital of Sichuan University. Clinical and endoscopic characteristics were summarized and analyzed retrospectively. GMS(Gomori methenamine silver), PAS(periodic acid-Schiff) and Giemsa staining technique were used to confirm Histoplasma capsulatum(H. capsulatum). The symptoms, signs, endoscopic presentations, radiographic imaging, pathological stain results and follow-up are presented as tables and ***: The cases were male patients, ranging from 33 to 61 years old, and primarily presented with nonspecific symptoms such as irregular fever, weight loss, abdominal pain and distention. Hepatosplenomegaly and lymphadenopathy were the most common signs. Endoscopic manifestations were localized or diffuse congestion, edema, ulcers, and polypoid nodules with central erosion involving the terminal ileum, ascendingcolon, transverse colon, descending colon, sigmoid colon and rectum, similar to intestinal tuberculosis, tumor, and inflammatory bowel disease. Numerous yeast-like pathogens testing positive for PAS and GMS stains but negative for Giemsa were detected in the cytoplasm of the histiocytes, which were highly suggestive of H. ***: Immunocompetent individuals suffering from histoplasmosis are rarely reported. It is necessary that gastroenterologists and endoscopists consider histoplasmosis as a differential diagnosis, even in immunocompetent patients.

关键词： Intestinal histoplasmosis Disseminated histoplasmosis Immunocompetence Endoscopic characteristics Differential diagnosis

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Rapidly counting atomic planes of ultra-thin MoSe2 nanosheets(1≤n≤4)on SiO2/Si substrate

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Rare Metals 2016年第8期35卷 632-636页

作者： yi-ping wang Hui-Jun Zhou Gui-Hua Zhao Tian-Long Xia Lei wang Le wang Li-Yuan Zhang Department of Physics Renmin University of ChinaBeijing 100872China Beijing Key Laboratory of Opto-electronic Functional Materialsand Micro-nano Devices Renmin University of China Department of Power and Electrical Engineering Northwest A&F UniversityYangling 712100ShaanxiChina

The optical, thermal and electrical properties of ultra-thin two-dimensional （2D） crystal materials are highly related to their thickness. Therefore, identifying the atomic planes of few-layer crystal materials rapidly is crucial to fundamental study. Here, a simple technique was demonstrated based on optical contrast for counting atomic planes （n） of few-layer MoSe2 on SiO2/Si substrates. It is found that the optical contrast of single-layer MoSe2 depends on light wavelength and thickness of SiO2 on Si substrate. The data calculated based on a Fresnel law-based model as well as atomic force microscopy （AFM） mea- surements fit well with the values measured by spectro- scopic ellipsometer. Furthermore, the calculated and measured contrasts were integral and plotted, which can be used to determine the MoSe2 atomic planes （1 ≤ n ≤ 4） accurately and rapidly.

关键词： Thickness identification Optical contrast MoSe2 Optical microscopy

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High resolution deep imaging of a bright radio quiet QSO at z～3

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Research in Astronomy and Astrophysics 2015年第5期15卷 673-686页

作者： yi-ping wang Wei He Toru Yamada Ichi Tanaka Masanori Iye Tuo Ji Key Laboratory of Optical Astronomy National Astronomical Observatories Chinese Academy of Sciences Tohoku University Aramaki Aoba Sendai 980-8578 Japan Subaru telescope National Astronomical Obs. of Japan 650 North A’ohoku Place Hilo Hawaii 96720 USA National Astronomical Obs. of Japan 2-21-1 Osawa Mitaka Tokyo 181-8588 Japan Polar Research Institute of China

We have obtained deep J and Ks-band images centered on a bright radio quiet QSO UM 402 （Zem = 2.856） using the IRCS camera and adaptive optics systems that are part of the Subaru Telescope, as well as retrieved WFC3/F140W archive images of this object. A faint galaxy （ink = 23.32 ±0.05 in the Vega magnitude system） that lies ～2.4″north of the QSO sightline has been clearly resolved in all three deep high resolution datasets, and appears as an irregular galaxy with two close components in the Ks-band images （separation ～ 0.31″）. Given the small impact parameter （b = 19.6 kpc, at Zlls = 2.531）, as well as the red color of （J - Ks）vega ～1.6, it might be a candidate galaxy giving rise to the Lyman Limit system absorption at Zabs = 2.531 seen in the QSO spectrum. After carefully subtracting the point spread function from the QSO images, the host galaxy of this bright radio quiet QSO at z ～ 3 was marginally revealed. We placed a lower limit on the host component of mk～ 23.3 according to our analyses.

关键词： galaxies active -- galaxies high redshift -- quasars general -- instru- mentation adaptive optics

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A Self-Healing Elastomer with Extremely High Toughness Achieved by Acylsemicarbazide Hydrogen Bonding and Cu^(2+)-Neocuproine Coordination Interactions

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Chinese Journal of Polymer Science 2024年第10期42卷 1425-1434,I0007页

作者： Xiao-Ming An yi-ping wang Tang-Song Zhu Chong Xing Xu-Dong Jia Qiu-Hong Zhang Key Laboratory of High Performance Polymer Material and Technology of MOE Department of Polymer Science and EngineeringSchool of Chemistry and Chemical EngineeringNanjing UniversityNanjing210093China State Key Laboratory of Coordination Chemistry Nanjing UniversityNanjing210093China

Elastomers with high mechanical toughness can guarantee their durability during service ***-healing ability,as well as recyclability,can also extend the life of materials and save the consuming cost of the *** efforts have been dedicated to promoting the mechanical toughness as well as the self-healing capability of elastomers at the same time,while it remains a challenge to balance the trade-off between the above properties in one *** we proposed a molecular design driven by dual interactions of acylsemicarbazide hydrogen bonding and Cu^(2+)-neocuproine coordination *** introducing the reversible multiple hydrogen bonds and strong coordination bonds,we successfully fabricated an extremely tough and self-healing *** elastomer can achieve an impressive top-notch toughness of 491 MJ/m^(3).Furthermore,it boasted rapid elastic restorability within 10 min and outstanding crack tolerance with high fracture energy(152.6kJ/m^(2)).Benefiting from the combination of dynamic interactions,the material was able to self-repair under 80℃conveniently and could be reprocessed to restore the exceptional mechanical properties.

关键词： Metal-ligand coordination Hydrogen bond Ultra-tough elastomer Self-healing

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Synthesis and Antioxidant Activity of Sapriparaquinone Analogues

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Chinese Chemical Letters 2006年第9期17卷 1177-1180页

作者： Fei DENG Fu Jun ZHANG Ming ZHAO yi ping wang Jin Sheng ZHANG State Key Laboratory of Drug Research Shanghai Institute of Materia Medica Shanghai Institutes for Biological Sciences Chinese Academy of Sciences Shanghai 201203

Twenty two sapriparaquinone derivatives were synthesized and their antioxidant activities were evaluated in vitro. Many of this kind of compounds demonstrated potent antioxidant activity against lipid peroxidation, especially compound 7 （IC50 = 3.7 μg/mL）. The preliminary structure-activity relationship of sapriparaquinone derivatives was discussed.

关键词： Synthesis sapriparaquinone antioxidant activity.

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