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Empirical likelihood-based inference in a partially linear model for longitudinal data

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Science china Mathematics 2008年第1期51卷 115-130页

作者： xue liugen~(1+) & zhu lixing~2.1.college of ap.lied sciences, beijing university of technology, beijing 10002., china 2 Department of Mathematics, Hong Kong Baptist university, Hong Kong, china college of ap.lied sciences Beijing University of Technology Beijing 100022 China Department of Mathematics Hong Kong Baptist University Hong Kong China

A partially linear model with longitudinal data is considered, empirical likelihood to infer- ence for the regression coefficients and the baseline function is investigated, the empirical log-likelihood ratios is proven to be asymptotically chi-squared, and the corresponding confidence regions for the pa- rameters of interest are then constructed. Also by the empirical likelihood ratio functions, we can obtain the maximum empirical likelihood estimates of the regression coefficients and the baseline function, and prove the asymptotic normality. The numerical results are conducted to compare the performance of the empirical likelihood and the normal approximation-based method, and a real example is analysed.

关键词： partially linear model empirical likelihood confidence region longitudinal data 62G05 62.1. 62G20

Synergistic governance:china's roadmap to improved health through climate and clean air actions

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Environmental Science and Ecotechnology 2024年第4期20卷 14-15页

作者： Tao xue Tong zhu Institute of Reproductive and Child Health National Health Commission Key Laboratory of Reproductive Health and Department of Epidemiology and BiostatisticsMinistry of Education Key Laboratory of Epidemiology of Major Diseases(PKU)School of Public HealthPeking University Health Science CentreBeijingChina SKL-ESPC and SEPKL-AERM College of Environmental Sciences and EngineeringCenter for Environment and HealthPeking UniversityBeijing100871China

The COP28's inaugural Health Day highlighted the growing recognition of the connection between climate and health,while china's State Council released its third air quality action plan aiming at ongoing health *** Synergetic Roadmap project[1],which aims to track china's progress towards carbon neutrality and clean air,provides valuable insights to answer a set of intriguing questions concerning environmental health determinants,their source sectors,and the methods for harmonizing disparate actions to maximize health gain.

关键词： concerning neutral clean

Cu(Ⅱ) Potentiation of Alzheimer Aβ1-40 Cytotoxicity and Transition on its Secondary Structure

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Acta Biochimica et Biophysica Sinica 2006年第11期38卷 765-772页

作者： xue-Ling DAI~1 Ya-Xuan SUN~2 Zhao-Feng JIANG~2* 1 college of Life Science,Capital Normal university,beijing 100037,china 2 college of ap.lied sciences and Humanities,beijing Union university,beijing 100083,china college of Life Science Capital Normal UniversityBeijing 100037 China college of ap.lied sciences and Humanities Beijing Union UniversityBeijing 100083 China

Mounting evidence has shown that dyshomeostasis of the redox-active biometals such as Cuand Fe can lead to oxidative stress,which plays a key role in the neuropathology of Alzheimer's disease（AD）.Here we demonstrate that with the formation of Cu（Ⅱ）·Aβ1-40 complexes,copper markedly potentiatesthe neurotoxicity exhibited by β-amyloid peptide （Aβ）.A greater amount of hydrogen peroxide was releasedwhen Cu（Ⅱ）·Aβ1-40 complexes was added to the xanthine oxidase/xanthine system detected by potassiumiodide *** bound to Aβ1-40 was observed by electron paramagnetic resonance（EPR） *** dichroism （CD） studies indicated that copper chelation could cause a structuraltransition of Aβ.The addition of copper to Aβ introduced an increase on β-sheet as well as α-helix,whichmay be responsible for the aggregation of Aβ.We hypothesized that Aβ aggregation induced by copper maybe responsible for local injury in *** interaction between Cu2+and Aβ also provides a possible mechanismfor the enrichment of metal ions in amyloid plaques in the AD brain.

关键词： Alzheimer’s disease Cu(Ⅱ)·Aβ1-40 complex neuron injury Aβ secondary structure

Health-oriented strategies are needed to optimize china’s 2025 clean air action plan

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Science Bulletin 2024年第13期69卷 2007-2008页

作者： Tao xue Ning Kang Wei Wan Tong zhu Institute of Reproductive and Child Health/National Health Commission Key Laboratory of Reproductive Health and Department of Epidemiology and Biostatistics/Ministry of Education Key Laboratory of Epidemiology of Major Diseases(PKU) School of Public HealthPeking University Health Science CentreBeijing 100191China State Environmental Protection Key Laboratory of Atmospheric Exposure and Health Risk Management Center for Environment and HealthPeking UniversityBeijing 100871China Advanced Institute of Information technology Peking UniversityHangzhou 311215China Clean Air Asia Beijing 100600China college of Environmental sciences and Engineering Peking UniversityBeijing 100871China

Recently,china’s State Council issued the Continuous Improvement of Air Quality Action Plan(hereafter,the third action plan),which follows the Air Pollution Prevention and Control Action Plan(2.1.–2.1.)(hereafter,the first action plan)and the Three-Year Action Plan for Winning the Blue Sky Defense Battle(2.1.–2020)(hereafter the second action plan).The first two action plans yielded nationwide health benefits[1–3],from improving lung function[4]to saving medical expenditures[5].Based on our previous estimates[6],due to reductions in the fine particulate matter(PM2.5)level,implementation of the first and second action plans was expected to increase life expectancy by 2.1. and 3.68 months.

关键词： action hereafter nationwide

ASYMPTOTIC PROPERTIES OF ESTIMATORS IN PARTIALLY LINEAR SINGLE-INDEX MODEL FOR LONGITUDINAL DATA

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Acta Mathematica Scientia 2010年第3期30卷 677-687页

作者：田萍杨林薛留根 Department of Mathematics Xuchang University college of ap.lied sciences Beijing University of Technology

In this article, a partially linear single-index model /or longitudinal data is investigated. The generalized penalized spline least squares estimates of the unknown parameters are suggested. All parameters can be estimated simultaneously by the proposed method while the feature of longitudinal data is considered. The existence, strong consistency and asymptotic normality of the estimators are proved under suitable conditions. A simulation study is conducted to investigate the finite sample performance of the proposed method. Our approach can also be used to study the pure single-index model for longitudinal data.

关键词： Longitudinal data partially linear single-index model penalized spline strong consistency asymptotic normality

Thermal expansion in dysprosium tungstate Dy_(10)W_2O_(21)

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Rare Metals 2002年第3期21卷 182-185页

作者： XINGXianran, zhu Zhenqi, QI xue, and LIU GuirongDepartment of Physical Chemistry, university of Science and technology beijing, beijing 100083, china Department of Physical Chemistry University of Science and Technology Beijing 北京 100083

The complex oxide Dy_(10)W_2O_(21) was synthesized by a solid-state reactionand isolated in cubic symmetry by an X-ray diffractometry (XRD) method. Differential scanningcalorimetry (DSC) measurements show that the compound is thermodynamically stable. The intrinsicthermal expansion coefficients were determined by extra-power powder X-ray diffractometry from roomtemperature to 1000 deg C: linear coefficient alpha-bar = 1.07 X 10^(-5) deg C^(-1) and bulkcoefficient beta-bar = 3.20 X 10^(-5) deg C^(-1). Dilatometry was used to measure the extrinsicthermal expansion coefficient (9.2 X 10^(-6) deg C^(-1)).

关键词： Dy_(10)W_2O_(21) thermal expansion cell parameter thermodynamic stability

Large-scale manufacturing of functional single-atom ink for convenient glucose sensing

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Nano Research 2024年第8期17卷 7256-7263页

作者： Muyu Yan Xiaofei zhu Can Xiong Xiao Han Zhenggang xue Yuen Wu Department of Endocrinology Institute of Endocrine and Metabolic DiseasesThe First Affiliated Hospital of USTCDivision of Life Sciences and MedicineUniversity of Science and Technology of ChinaHefei 230001China Deep Space Exploration Laboratory University of Science and Technology of ChinaHefei 230026China NEST Laboratory Department of PhysicsDepartment of ChemistryCollege of ScienceShanghai UniversityShanghai 200444China Center of Advanced Nanocatalysis(CAN) Department of Applied ChemistryUniversity of Science and Technology of ChinaHefei 230026China

Printing techniques hold great potential in the manufacture of electronics such as sensors,micro-supercapacitors,and flexible ***,developing large-scale functional conductive inks with appropriate rheological properties and active components still remains a ***,through optimizing the formulations of ink,iron single sites supported N-doped carbon black(Fe_(1)-NC)inks can serve as both conductive electrodes and high-reactive catalysts to realize convenient glucose detection,which pronouncedly reduces the dosage of enzyme and simplifies the sensors *** detail,utilizing in-situ pyrolysis method,Fe_(1)-NC single-atom catalysts(SACs)are prepared in bulk(dekagram-level).The batched Fe_(1)-NC SACs materials can be uniformly mixed with modulated ink to realize the screen printing with high resolution and ***,the whole scalable preparation and ink-functional process can be extended to various metals(including Co,Ni,Cu,and Mn).The introduction of highly active Fe_(1)-NC sites reduces the amount of enzyme used in glucose detection by at least 50%,contributing to the cost reduction of *** strategy in harnessing the SACs onto the carbon inks thus provides a broad prospect for the low-cost and large-scale printing of sensitive sensing devices.

关键词： large-scale manufacturing single-atom inks screen printing glucose sensing low enzyme dosage

Striking Stabilization Effect of Spinel Cobalt Oxide Oxygen Evolution Electrocatalysts in Neutral pH by Dual-Sites Iron Incorporation

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Energy & Environmental Materials 2024年第2期7卷 152-160页

作者： Shuairu zhu xue Wang Jiabo Le Na An Jianming Li Deyu Liu Yongbo Kuang Key Laboratory of Advanced Fuel Cells and Electrolyzers technology of Zhejiang Province Ningbo Institute of Materials Technology and Engineering Chinese Academy of Sciences1219 Zhongguan West RoadNingbo 315201China Zhejiang Institute of Tianjin university 85 Zhongguan West RoadNingbo 315201China Research Center of New Energy Research Institute of Petroleum Exploration&Development20 Xueyuan RoadBeijing 100083China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of Sciences19(A)Yuquan RoadBeijing 100049China

Developing stable and efficient nonprecious-metal-based oxygen evolution catalysts in the neutral electrolyte is a challenging but essential goal for various electrochemical ***,cobalt-based spinels have drawn a considerable amount of attention but most of them operate in alkali ***,the frequently studied Co-Fe spinel system never exhibits appreciable stability in nonbasic conditions,not to mention attract further investigation on its key structural motif and transition states for activity ***,we report exceptional stable Co-Fe spinel oxygen evolution catalysts(~30%Fe is optimal)in a neutral electrolyte,owing to its unique metal ion arrangements in the crystal *** introduced iron content enters both the octahedral and tetrahedral sites of the spinel as Fe^(2+)and Fe^(3+)(with Co ions having mixed distribution as well).Combining density functional theory calculations,we find that the introduction of Fe to Co_(3)O_(4)lowers the covalency of metal-oxygen bonds and can help suppress the oxidation of Co^(2+/3+)and 0^(2-).It implies that the Co-Fe spinel will have minor surface reconstruction and less lattice oxygen loss during the oxygen evolution reaction process in comparison with Co_(3)O_(4)and hence show much better *** findings suggest that there is still much chance for the spinel structures,especially using reasonable sublattices engineering via multimetal doping to develop advanced oxygen evolution catalysts.

关键词： dual-sites iron electrocatalyst stability neutral electrolyte oxygen evolution reaction spinel oxides

Size-dependent hydroxyl radicals generation induced by SiO_2 ultra-fine particles: The role of surface iron

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Science china Chemistry 2009年第7期52卷 1033-1041页

作者： SHANG Yu1, zhu Tong1, LI Yi1,2 & ZHAO JinCai3 1 college of Environmental sciences and Engineering, Peking university, beijing 100871, china 2 Chinese Academy of Meteorological sciences, beijing 100871, china 3 Institute of Chemistry, Chinese Academy of sciences, beijing 100871, china 1. college of Environmental sciences and Engineering Peking University Beijing 100871 China 2. Chinese Academy of Meteorological sciences Beijing 100871 China 3. Institute of Chemistry Chinese Academy of Sciences Beijing 100871 China

Oxidative stress and hydroxyl radicals (·OH) play important roles in adverse health effects caused by inhalable ambient air particles (PM10). The ultra-fine fraction of PM10 has been hypothesized as one of the critical contributors to ·OH generation. Both in vivo and in vitro studies have shown that ultra-fine particles (UFPs) or nano-particles generate more ·OH than larger particles with identical mass and composition. Both the surface area and surface-adsorbed redox-active metals have been suggested as factors to determine the oxidative capacity of UFPs. In this study, the ·OH-generating capability of dif-ferent sizes of SiO2 particles was investigated in order to determine which factor influences particle-induced ·OH generation. The amount of ·OH generated in both acellular and cellular systems was quantified using a capillary electrophoresis method following exposure to SiO2 particles with diameters of 14, 100, and 500 nm. The amount of ·OH was strongly dependent on particle size, and a significant enhancement was observed only with 14 nm particles. Further studies indicated a close association between ·OH and iron ion concentration (R2 = 0.812, p1). Washed particles, with their surface iron being removed, did not generate ·OH. The iron-containing leachate from these washings was able to enhance ·OH production as untreated particles did. Therefore, the presence of adsorbed iron on the surface of the SiO2 particles is presented as a possible mechanism of UPFs-induced ·OH generation. The SiO2 acted as an inert substrate, and the surface of ultra-fine SiO2 particles acted as a carrier for iron.

关键词： ultra-fine particles nano-particles ·OH oxidative stress size-effect