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Automated estimation of stellar fundamental parameters from low resolution spectra: the PLS method

Research in Astronomy and Astrophysics 2009年第6期9卷 712-724页

作者： jian-nan zhang a-li luo yong-heng zhao National Astronomical Observatories Chinese Academy of Sciences Beijing 100012 China

PLS （Partial Least Squares regression） is introduced into an automatic estimation of fundamental stellar spectral parameters. It extracts the most correlative spectral component to the parameters （Teff, log g and [Fe/H]）, and sets up a linear regression function from spectra to the corresponding parameters. Considering the properties of stellar spectra and the PLS algorithm, we present a piecewise PLS regression method for estimation of stellar parameters, which is composed of one PLS model for Teff, and seven PLS models for log g and [Fe/H] estimation. Its performance is investigated by large experiments on flux calibrated spectra and continuum normalized spectra at different signal-to-noise ratios （SNRs） and resolutions. The results show that the piecewise PLS method is robust for spectra at the medium resolution of 0.23 nm. For low resolution 0.5 nm and 1 nm spectra, it achieves competitive results at higher SNR. Experiments using ELODIE spectra of 0.23 nm resolution illustrate that our piecewise PLS models trained with MILES spectra are efficient for O ～ G stars： for flux calibrated spectra, the systematic offsets are 3.8%, 0.14 dex, and -0.09 dex for Teff, log g and [Fe/H], with error scatters of 5.2%, 0.44 dex and 0.38 dex, respectively; for continuum normalized spectra, the systematic offsets are 3.8%, 0.12dex, and -0.13 dex for Teff, log g and [Fe/H], with error scatters of 5.2%, 0.49 dex and 0.41 dex, respectively. The PLS method is rapid, easy to use and does not rely as strongly on the tightness of a parameter grid of templates to reach high precision as Artificial Neural Networks or minimum distance methods do.

关键词： methods data analysis -- methods statistical -- stars fundamental param- eters (classification, temperatures, metallicity) -- techniques spectroscopic -- surveys

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Metal-organic nanosheet assembly ions sieving membrane for precise lithium ion and anion/solvent separation toward robust lithium metal battery

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Science China Chemistry 2024年第10期67卷 3320-3327页

作者： jian-Qiang Shen Tian-Tian zhao Ying-li Song lingjuan zhang Ya-nan Gao Xiao-nan Cui Peng zhao Xian-Ming zhang Key Laboratory of Magnetic Molecules&Magnetic Information Materials Ministry of EducationSchool of Chemistry&Material ScienceShanxi Normal UniversityTaiyuan 030031China College of Chemistry and Chemical Engineering Taiyuan University of TechnologyTaiyuan 030024China

Metal-organic nanosheets(MONs)as a novel material with tunable pore structures and low mass transfer resistance,have emerged as molecular sieves for the separation of gases and *** theory,they can also serve as ion sieves for lithium metal batteries(LMBs),realizing the high-energy and dendritic free ***,there are rarely relevant reports,because it is difficult to simultaneously balance efficient ion sieving ability,high ion passing rate and high electrochemical ***,we synthesized a stable ultrathin MON[Zn_(2)(Bim)_(4)]([Zn_(2)(Bim)_(4)]nanosheet,HBim=benzimidazolate),which can achieve both efficient lithium ion sieving ability,high lithium ion passing rate and high electrochemical stability at the same *** separator assembled by this MON exhibits high li^(+)transfer number of 0.81 due to the accurate lithium ion and anion/solvent *** battery containing such separator shows high lithium ionic conductivity of 0.74 m S cm^(-1)and low activation energy of 0.099 eV,which can be attributed to the nanometer level thickness and the ion sieving *** is more,we realized the application of MONs-based ion sieves in LMBs with intercalation cathodes for the first *** the liFePO_(4)|li battery with as-assembled separator demonstrates improved Coulombic efficiency(>99%)and significantly extended cycling life(>1600 cycles)with 80%capacity retention.

关键词： lithium sieving membrane metal-organic nanosheets lithium metal battery lithium ion and anion separation lithium ion and solvent separation

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Manipulating the Phase Transition Behavior of Dual Temperature-Responsive Block Copolymers by Adjusting Composition and Sequence

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Chinese Journal of Polymer Science 2024年第2期42卷 176-187,I0006页

作者： Zhi Zou Xiang Xu Hai-Tao zhao jian-nan Cheng Wei-Wei He li-Fen zhang Zhen-Ping Cheng Suzhou key Laboratory of Macromolecular Design and Precision Synthesis Jiangsu Key Laboratory of Advanced Functional Polymer Design and ApplicationState and Local Joint Engineering Laboratory for Novel Functional Polymeric MaterialsCollege of ChemistryChemical Engineering and Materials ScienceSoochow UniversitySuzhou215123China State Key Laboratory of Radiation Medicine and Protection School for Radiological and Interdisciplinary Sciences(RAD-X)and Collaborative Innovation Center of Radiation Medicine of JiangsuSoochow UniversitySuzhou215123China

Temperature-responsive polymers have garnered significant attention due to their ability to respond to external *** this work,dual temperature-responsive block copolymers are synthesized via reversible addition-fragmentation chain transfer polymerization(RAFT)polymerization utilizing zwitterionic monomer methacryloyl ethyl sulfobetaine(SBMA) and N-isopropyl acrylamide(NIPAAm) as *** thermal responsive behaviors can be easily modulated by incorporating additional hydrophobic monomer benzyl acrylate(BN) or hydrophilic monomer acrylic acid(AA),adjusting concentration or pH,or varying the degree of polymerization of the block chain *** cloud points of the copolymers are determined by UV-Vis spectrophotometry,and these copolymers exhibit both controlled upper and lower critical solu bility temperatures(LCST and UCST) in aqueous *** study analyzes and summarizes the influencing factors of dual temperature responsive block copolymers by exploring the effects of various conditions on the phase transition temperature of temperature-sensitive polymers to explore the relationship between their properties and environment and structure to make them more selective in terms of temperature application range and regulation *** is very interesting that the introduction of poly-acrylic acid(PAA) segments in the middle of di-block copolymer PSBMA_(55)-b-PNIPAAm_(80) to form PSBMA_(55)-b-PAA_(x)-b-PNIPAAm_(80) results in a reversal of temperature-responsive behaviors from 'U'(LCST UCST) type,while the copolymer PSBMA_(55)-b-P(NIPAAm_(80)-co-AA_(x)) *** work provides a clue for tuning the phase transition behavior of polymers for manufacture of extreme smart materials.

关键词： Temperature responsive polymers High critical solubility temperature(UCST) Low critical solubility temperature(LCST) Block copolymers

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Optical and electrical anisotropy regulation engineering of low-dimensional materials toward polarized detection and imaging applications

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Rare Metals 2024年第7期43卷 2968-2993页

作者： jian-Bin zhang nan Zhou li-Hui zhang Cong-Hui Shang Jia-Xuan li Yi zhao Guo-Hui Jia Ru-Sen Yang Hua Xu Xiao-Bo li Shaanxi Joint Key Laboratory of Graphene Shaanxi Key Laboratory of High-Orbits-Electron Materials and Protection Technology for AerospaceShaanxi Joint Key Laboratory of GrapheneSchool of Advanced Materials and NanotechnologyXidian UniversityXi'an710126China Guangzhou Institute of Technology Xidian UniversityGuangzhou 710068China Xi'an Thermal Power Research Institute Co. LtdXi'an 710054China Key Laboratory of Applied Surface and Colloid Chemistry Ministry of EducationShaanxi Key Laboratory for Advanced Energy DevicesShaanxi Engineering Lab for Advanced Energy TechnologySchool of Materials Science and EngineeringShaanxi Normal UniversityXi'an Xi'an 710119China

Polarized-sensitive image sensors are a kind of photodetector with great development potential due to their enhanced ability to detect and identify the target objects from the aspect of spatial,spectral and polarized ***,low-dimensional anisotropic materials with inherent anisotropic properties,ultrathin thickness,tunable bandgap and feasible integration with complementary metal oxide semiconductor(CMOS)fabrication processes have attracted great interest for their facilitation of polarized photodetector devices *** the polarized detection performance of low-dimensional materials to satisfy realistic needs stimulates the exploration of modulation of anisotropic *** this review,we comprehensively introduce the latest research progress in modulating the optical and optoelectronic anisotropy characteristics of low-dimensional *** strategy of anisotropy regulation through crystal structure engineering and coupling system is discussed ***,the latest progress in image recognition applications using anisotropic low-dimensional materials is reviewed in ***,we summarize the challenge and propose future opportunities in the practical application of polarized-sensitive imaging photodetectors based on low-dimensional anisotropic materials.

关键词： Anisotropy Polarized detection Image recognition Low-dimensional materials

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Stepped-up development of accelerator mass spectrometry method for the detection of ^(60)Fe with the HI-13 tandem accelerator

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Nuclear Science and Techniques 2024年第4期35卷 136-143页

作者： Yang zhang Sheng-Quan Yan Ming He Qing-zhang zhao Wen-Hui zhang Chao-Xin Kan jian-Ming Zhou Kang-Ning li Xiao-Fei Wang jian-Cheng liu zhao-Hua Peng Zhuo liang Ai-ling li jian Zheng Qi-Wen Fan Yun-Ju li You-Bao Wang Zhi-Hong li Yang-Ping Shen Ding nan Wei nan Yu-Qiang zhang Jia-Ying-Hao li Jun-Wen Tian jiang-lin Hou Chang-Xin Guo Zhi-Cheng zhang Ming-Hao Zhu Yu-Wen Chen Yu-Chen jiang Tao Tian Jin-Long Ma Yi-Hui liu Jing-Yu Dong Run-Long liu Mei-Yue-nan Ma yong-Shou Chen Wei-Ping liu Bing Guo China Institute of Atomic Energy P.O.Box 275(10)Beijing 102413China College of Science Southern University of Science and TechnologyShenzhen 518055China School of Physics Xi’an Jiaotong UniversityXi’an 710049China

The Moon provides a unique environment for investigating nearby astrophysical events such as *** samples retain valuable information from these events,via detectable long-lived“fingerprint”radionuclides such as^(60)*** this work,we stepped up the development of an accelerator mass spectrometry(AMS)method for detecting^(60)Fe using the HI-13tandem accelerator at the China Institute of Atomic Energy(CIAE).Since interferences could not be sufficiently removed solely with the existing magnetic systems of the tandem accelerator and the following Q3D magnetic spectrograph,a Wien filter with a maximum voltage of±60 kV and a maximum magnetic field of 0.3 T was installed after the accelerator magnetic systems to lower the detection background for the low abundance nuclide^(60)Fe.A 1μm thick Si_(3)N_(4) foil was installed in front of the Q3D as an energy *** particle detection,a multi-anode gas ionization chamber was mounted at the center of the focal plane of the ***,an^(60)Fe sample with an abundance of 1.125×10^(-10)was used to test the new AMS *** results indicate that^(60)Fe can be clearly distinguished from the isobar^(60)*** sensitivity was assessed to be better than 4.3×10^(-14)based on blank sample measurements lasting 5.8 h,and the sensitivity could,in principle,be expected to be approximately 2.5×10^(-15)when the data were accumulated for 100 h,which is feasible for future lunar sample measurements because the main contaminants were sufficiently separated.

关键词： Accelerator mass spectrometry Wien filter Isobar separation Supernovae Chang'e-5 lunar samples

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Searching for the Highest Energy of Pulsation and Critical Luminosity of Swift J0243.6+6124 Observed by Insight-HXMT

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Research in Astronomy and Astrophysics 2024年第5期24卷 61-69页

作者： Qing-Xia zhao Xian Hou Ming-Yu Ge Shuang-nan zhang Yun-Xiang Xiao You-li Tuo Zi-Xu Yang ling-Da Kong Jin-Lu Qu Shu zhang jian-Cheng Wang Yunnan Observatories Chinese Academy of SciencesKunming 650216China Key Laboratory of Particle Astrophysics Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China University of Chinese Academy of Sciences ChineseAcademy of SciencesBeijing 100049China Key Laboratory for the Structure and Evolution of Celestial Objects Chinese Academy of SciencesKunming 650216China Institut fur Astronomic und Astrophysik Sand 1D-72076 TabingenGemany School of Physics and Optoelectronic Engineering Shandong University of TechnologyZibo 255000China

Owing to the broad energy coverage of Insight-HXMT in the hard X-ray band,we detected the highest energy of pulsation exceeding 200 keV around the 2017–2018 outburst peak of the first Galactic pulsating ultraluminous X-ray source (PULX) Swift J0243.6+6124,which is the highest energy detected from PULXs to *** also obtained the highest energy of pulsation of every exposure during the outburst in 2017–2018,and found the highest energy is roughly positively correlated with *** our newly developed method,we identified the critical luminosity being 4×10^(38)erg s^(-1) when the main peaks of the low and high energy pulse profiles became aligned,which separates the fan-beam dominated and pencil-beam dominated accretion *** the critical luminosity,the phase of the main peak shifted gradually from 0.5 to 0.8 until the outburst peak in al energy bands is reached,which is in agreement with the phase shift found previously at low *** result is consistent with what is derived from spectral analysis.

关键词： (stars:)pulsars-individual(Swift J0243.6+6124)-X-rays binaries–stars neutron

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Silicon-based optoelectronic heterogeneous integration for optical interconnection

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Chinese Physics B 2024年第2期33卷 1-9页

作者：李乐良李贵柯张钊刘剑吴南健王开友祁楠刘力源 Institute of Semiconductors Chinese Academy of SciencesBeijing 100083China Center of Material Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China

The performance of optical interconnection has improved dramatically in recent ***-based optoelectronic heterogeneous integration is the key enabler to achieve high performance optical interconnection,which not only provides the optical gain which is absent from native Si substrates and enables complete photonic functionalities on chip,but also improves the system performance through advanced heterogeneous integrated *** paper reviews recent progress of silicon-based optoelectronic heterogeneous integration in high performance optical *** research status,development trend and application of ultra-low loss optical waveguides,high-speed detectors,high-speed modulators,lasers and 2D,2.5D,3D and monolithic integration are focused on.

关键词： silicon-based heterogeneous integration heterogeneous integrated materials heterogeneous integrated packaging optical interconnection

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scRNA-seq reveals that origin recognition complex subunit 6 regulates mouse spermatogonial cell proliferation and apoptosis via activation of Wnt/β-catenin signaling

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Asian Journal of Andrology 2024年第1期26卷 46-56页

作者： Shi-Wei liu Jia-Qiang luo liang-Yu zhao Ning-Jing Ou Chao-Yang Yu-Xiang zhang Hao-Wei Bai Hong-Fang Sun jian-Xiong zhang Chen-Cheng Yao Peng li Ru-Hui Tian Zheng li Zi-Jue Zhu Department of Andrology Center for Men's HealthUrologic Medical CenterShanghai General HospitalShanghai Jiao Tong University School of MedicineShanghai 200080China State Key Lab of Reproductive Medicine Nanjing Medical UniversityNanjing 211166China Shanghai Key Lab of Reproductive Medicine Shanghai Jiao Tong University School of MedicineShanghai 200080China Department of Urology Guangdong Provincial Key Laboratory of Biomedical ImagingThe Fifth Affiliated HospitalSun Yat-sen UniversityZhuhai 519000China Department of Urology First Affiliated Hospital of Nanjing Medical UniversityNanjing 210029China

The regulation of spermatogonial proliferation and apoptosis is of great significance for maintaining *** single-cell RNA sequencing(scRNA-seq)analysis of the testis was performed to identify genes upregulated in *** scRNAseq analysis,we identified the spermatogonia upregulated gene origin recognition complex subunit 6(Orc6),which is involved in DNA replication and cell cycle regulation;its protein expression in the human and mouse testis was detected by western blot and *** explore the potential function of Orc6 in spermatogonia,the C18-4 cell line was transfected with control or Orc6 ***,5-ethynyl-2-deoxyuridine(EdU)and terminal deoxynucleotidyl transferase dUTP nick end labeling(TUNEL)assays,flow cytometry,and western blot were used to evaluate its effects on proliferation and *** was revealed that ORC6 could promote proliferation and inhibit apoptosis of C18-4 *** RNA sequencing and bioinformatics analysis indicated that Orc6 was involved in the activation of wingless/integrated(Wnt)/β-catenin *** blot revealed that the expression ofβ-catenin protein and its phosphorylation(Ser675)were significantly decreased when silencing the expression of *** findings indicated that Orc6 was upregulated in spermatogonia,whereby it regulated proliferation and apoptosis by activating Wnt/β-catenin signaling.

关键词： cell proliferation ORCG scRNA-seq analysis spermatogonia Wnt/β-catenin signaling

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TOPK Inhibition Enhances the Sensitivity of Colorectal Cancer Cells to Radiotherapy by Reducing the DNA Damage Response

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Current Medical Science 2024年第3期44卷 545-553页

作者： Shi-gui PANG Xin zhang zhao-xin li li-fei HE Feng CHEN Ming-long liU Ying-ze HUANG jian-mei MO Kong-lan luo Juan-juan XIAO Feng ZHU Department of Oncology The Affiliated Hospital of Guilin Medical UniversityGuilin541001China Cancer Research Institute The Affiliated Hospital of Guilin Medical UniversityGuilin541001China Translational Medical Center Huaihe HospitalHenan UniversityKaifeng475000China Guangxi Key Laboratory of Molecular Medicine in liver Injury and Repair The Affiliated Hospital of Guilin Medical UniversityGuilin541001China

Objective Abnormal expression of T-lymphokine-activated killer cell-originated protein kinase(TOPK)was reported to be closely related to the resistance of prostate cancer to radiotherapy and to targeted drug resistance in lung ***,the role of TOPK inhibition in enhancing radiosensitivity of colorectal cancer(CRC)cells is *** study aimed to evaluate the radiosensitization of TOPK knockdown in CRC *** The expression of TOPK was detected in CRC tissues by immunohistochemistry,and the effect of TOPK knockdown was detected in CRC cells by Western ***-8 and clonogenic assays were used to detect the growth and clonogenic ability of CRC cells after TOPK knockdown combined with radiotherapy in CRC ***,proteomic analysis showed that the phosphorylation of TOPK downstream proteins changed after *** damage was detected by the comet *** in the DNA damage response signaling pathway were analyzed by Western blotting,and apoptosis was detected by flow *** The expression of TOPK was significantly greater in CRC tissues at grades 2–4 than in those at grade *** irradiation,CRC cells with genetically silenced TOPK had shorter comet tails and reduced expression levels of DNA damage response-associated proteins,including phospho-cyclin-dependent kinase 1(p-CDK1),phospho-ataxia telangiectasia-mutated(p-ATM),poly ADP-ribose polymerase(PARP),and meiotic recombination 11 homolog 1(MRE11).Conclusions TOPK was overexpressed in patients with moderately to poorly differentiated ***,TOPK knockdown significantly enhanced the radiosensitivity of CRC cells by reducing the DNA damage response.

关键词： T-lymphokine-activated killer cell-originated protein kinase colorectal cancer DNA damage response radiosensitivity

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Photonics-assisted THz wireless communication enabled by wide-bandwidth packaged backilluminated modified uni-traveling-carrier photodiode

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Opto-Electronic Science 2024年第7期3卷 20-29页

作者： Yuxin Tian Boyu Dong Yaxuan li Bing Xiong Junwen zhang Changzheng Sun Zhibiao Hao jian Wang Lai Wang Yanjun Han Hongtao li lin Gan nan Chi Yi luo Beijing National Research Center for Information Science and Technology(BNRist) Department of Electronic EngineeringTsinghua UniversityBeijing 100084China Key Laboratory of Information Science of Electromagnetic Waves(MoE) Department of Communication Science and EngineeringFudan UniversityShanghai 200433China Flexible Intelligent Optoelectronic Device and Technology Center Institute of Flexible Electronics Technology of THUJiaxing 314000China

This paper presents a wide-bandwidth back-illuminated modified uni-traveling-carrier photodiode(MUTC-PD)packaged with standard WR-5 rectangular waveguide for high-speed wireless *** optimized epitaxy structure and coplanar waveguide electrodes,the fabricated 4-μm-diameter PD exhibits ultra-flat frequency response and high saturation *** passive circuits including low-loss bias-tee and E-plane probe are designed to package the PD into a compact module with waveguide *** packaged PD module has demonstrated a flat frequency response with fluctuations within±2.75 d B over a broadband of 140–220 GHz and a high saturated output power of-7.8 d Bm(166μW)at 140 *** wireless communication applications,the packaged PD is used to implement 1-m free space transmission at carrier frequencies of 150.5 and 210.5 GHz,with transmission rates of 75 and 90 Gbps,respectively.

关键词： modified uni-traveling-carrier photodiode integrated bias-tee E-plane probe flat frequency response high saturation power WR-5 output THz wireless communications

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