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Presence of organophosphate flame retardants(OPEs)in different functional areas in residential homes in Beijing,China

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Journal of Environmental Sciences 2022年第5期34卷 277-285页

作者： Kun Lv Lu Bai Boyu Song Xindong Ma minmin hou Jie Fu Yali Shi Yawei Wang Guibin Jiang Environment Research Institute Shandong UniversityQingdao 266237China Research Center for Eco-Environmental Sciences Chinese Academy of SciencesBeijing 100085China Ministry of Ecology and Environment of the People’s Republic of China Foreign Environmental Cooperation CenterBeijing 100035China University of Chinese Academy of Sciences Beijing 100049China State Oceanic Administration Key Laboratory for Ecological Environment in Coastal Areas National Marine Environmental Monitoring CenterDalian 116023China School of Environment Hangzhou Institute for Advanced StudyUCASHangzhou 310000China

The production and application of organophosphate esters(OPEs)have dramatically increased in recent years due to their use as a replacement for brominated flame retardants.In this study,13 OPEs(∑_(13)OPEs)were analyzed in indoor air samples from kitchens and living rooms in 14 residential homes in Beijing,China.The concentrations of ∑_(13)OPEs in kitchen air samples(mean:13 ng/m^(3))were significantly(p<0.05)higher than in living room air samples(5.0 ng/m^(3)).In addition,paired window surface organic film samples were collected and analyzed to investigate film-air partitioning,exhibiting a mean concentration of ∑_(13)OPEs of 4100 ng/m^(2).The congener profiles showed that tris(2-chloroisopropyl)phosphate(TCPP)was the predominant compound in both window film samples(48%)and the corresponding indoor air sample(56%).The estimated daily intakes(EDI)of OPEs via indoor air inhalation were 2.8 and 1.4 ng/kg/day for infants and adults,respectively,both of which are below the reference dose values(RfDs).Overall,these findings indicate that OPEs in the indoor air environment of residential homes in Beijing are not likely to pose a health risk to the general population.

关键词： Organophosphate flame retardants (OPEs) Indoor environment Exposure assessment

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认知诊断模型中题目拟合评估的研究

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心理科学 2024年第2期47卷 474-484页

作者：高旭亮王芳夏林坡侯敏敏贵州师范大学心理学院贵州师范大学心理健康教育与咨询中心贵阳550025

有效应用认知诊断模型(cognitive diagnosis model,CDM)的一个关键步骤是检查模型和测验题目是否拟合。尽管已有研究将IRT中的题目拟合检验方法应用于CDM中,然而这些方法在CDM中的表现仍缺乏系统的比较研究。本研究通过模拟实验比较了χ... 详细信息

有效应用认知诊断模型(cognitive diagnosis model,CDM)的一个关键步骤是检查模型和测验题目是否拟合。尽管已有研究将IRT中的题目拟合检验方法应用于CDM中,然而这些方法在CDM中的表现仍缺乏系统的比较研究。本研究通过模拟实验比较了χ2,G2,S-χ2,z(r),z(l)和Stone-Q1的一类错误率和统计检验力。实验结果显示,综合一类错误率和统计检验力而言,当用ACDM作为生成模型时,z(r)和z(l)的效果最优;当生成模型是DINA或DINO时,在高质量测验中,z(r)的表现最好,而在低质量测验中,χ2和G2的表现更好。最后通过一个实测数据分析,进一步检验了题目拟合检验方法的实证应用效果。

关键词：认知诊断模型题目拟合一类错误率统计检验力

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287例盆腔及腹主动脉旁淋巴结清扫术与卵巢上皮性癌生存预后的临床分析(英文)

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The Chinese-German Journal of Clinical Oncology 2007年第5期6卷 492-496页

作者： Xiaoyun Yang minmin hou Kaixuan Yang Hongjing Wang Zhilan Peng Zeyi Cao Mingrong Xi Department of Obstetrics/Gynecology West China Second University Hospital Sichuan University Chengdu610041 China Department of Pathology West China Second University Hospital Sichuan University Chengdu 610041 China Department of Obstetrics/Gynecology The Second Teaching Hospital Sichuan University Chengdu 610041 China

Objective: To evaluate the relationship between the pelvic and para-aortic lymphadenectomy and the prognosis of epithelial ovarian cancer. Methods: 287 patients suffering from primary epithelial ovarian cancer from 1995 to 2005 were analyzed retrospectively. Results: The 3-, 5-, 10-year survival with systematic lymphadenectomy (SL) were slightly higher than those without SL, but there were no statistically significance (P > 0.05). The 3-, 5-, 10-year survival of clinical stages without SL were lower than those with SL, but there were no significant difference either (P > 0.05). The 3-,5-, and 10-year survival rates with SL were higher than those without SL with no statistically differences (P > 0.05) among the subgroups such as absent, ≤ 2 cm and > 2 cm residual tumor. The survival rates of the groups without residual tumor and the group with ≤ 2 cm residual tumor were significantly higher than that of > 2 cm (P < 0.005). On multivariate analysis, patient staging (P = 0.01) and size of residual disease after primary cytoreductive surgery (P < 0.001 and = 0.002, respectively) retained prognostic significance. SL was not proved to be an independent prognostic factor (P = 0.69). Conclusion: Systematic pelvic and para-aortic lymphadenectomy can not improve and prolong the survival time significantly.

关键词：盆腔腹主动脉淋巴结清扫术卵巢上皮性癌生存预后临床分析

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Palladium(Ⅱ)-Catalyzed Markovnikov Hydroalkynylation of Unactivated Terminal Alkenes

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Chinese Journal of Chemistry 2024年第1期42卷 29-34页

作者： Chuanqi hou Pinhong Chen Guosheng Liu Sstate Key Laboratory of Organometallic Chemistry and Shanghai Hongkong Joint Laboratory in Chemical SynthesisCenter for Excellence in Molecular SynthesisShanghai Institute of Organic ChemistryUniversity of Chinese Academy of SciencesChinese Academy of SciencesShanghai 200032China Chang-Kung Chuang Institute East China Normal UniversityShanghai 200062China

Alkynes are versatile synthons in organic synthesis,as well as important structural moieties in bioactive molecules.Recently,transition metal-catalyzed hydroalkynylation of alkenes has been developed with reactive alkenes and alkenes bearing directing groups.However,the regioselective hydroalkynylation of simple alkenes is still challenging.Herein,we have developed a palladium-catalyzed Markovnikov hydroalkynylation of unactivated terminal alkenes,which provides an efficient approach for the synthesis of branched alkynyl compounds under mild conditions.This reaction features excellent functional group tolerance,good reaction yields and excellent regioselectivity.Moreover,the asymmetric hydroalkynylation reaction has also been achieved with moderate enantioselectivity by introducing a sterically bulky chiral Pyox ligand.

关键词： Palladium catalysis Alkynylpalladation Unactivated terminal alkenes Markovnikov hydroalkynylation

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Preparation of Laser Cladding Coating Undercooling Cu-based Alloy and Co on Non-equilibrium Solidification Structure

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Journal of Wuhan University of Technology(Materials Science) 2024年第2期39卷 463-472页

作者：田徐铭 CAO Shichao hou Kai hou Xiaopeng WANG Hongfu 张煜 Department of Outpatient Xinzhou People’s HospitalXinzhou 034099China School of Mechanical Engineering North University of ChinaTaiyuan 030051China Department of Neurosurgery Xinzhou People’s HospitalXinzhou 034099China Department of Orthopedics Xinzhou People’s HospitalXinzhou 034099China

The effect of the gradient content of Co element on the solidification process of Cu-based alloy under deep under cooling conditions was explored.The non-equilibrium solidification structure of the under cooled alloy samples were analyzed.It is found that the rapidly solidified alloy has undergone twice grain refinement during the undercooling process.Characterization and significance of the maximum undercooling refinement structure of Cu60Ni35Co5 at T=253 K were analyzed.High-density defects were observed,such as dislocations,stacking faults networks,and twinning structures.The standard FCC diffraction pattern represents that it is still a single-phase structure.Based on the metallographic diagram,EBSD and TEM data analysis,it is illustrated that the occurrence of grain refinement under high undercooling is due to stress induced recrystallization.In addition,the laser cladding technology is used to coat Co-based alloy(Stellite12) coating on 304 stainless steel substrate;the microstructure of the coating cross-section was analyzed.It was found that the microstructure of the cross-section is presented as columnar crystals,planar crystals,and disordered growth direction,so that the coating has better hardness and wear resistance.By electrochemical corrosion of the substrate and coating,it can be seen that the Co and Cr elements present in the coating are more likely to form a dense passivation film,which improved the corrosion resistance of the coating.

关键词： non-equilibrium solidification structure undercooling recrystallization laser cladding coating

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Integral Operators Between Fock Spaces

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Chinese Annals of Mathematics,Series B 2024年第2期45卷 265-278页

作者： Yongqing LIU Shengzhao hou School of Mathematics and Statistics Changshu Institute of TechnologySuzhou 215006JiangsuChina School of Mathematical Sciences Soochow UniversitySuzhou 215006JiangsuChina

In this paper,the authors study the integral operator■induced by a kernel functionφ(z,·)∈F_α~∞between Fock spaces.For 1≤p≤∞,they prove that S_φ:F_α^(1)→F_α^(p)is bounded if and only if■where k_(a)is the ... 详细信息

关键词： Fock spaces Integral operators Normalized reproducing kernel

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In-Plane Dynamic Crushing Behaviors of a Vertex-Based Hierarchical Auxetic Honeycomb

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Acta Mechanica Solida Sinica 2024年第1期37卷 53-62页

作者： Yichen Zan Xiuhui hou Zichen Deng School of Mechanics Civil Engineering and ArchitectureNorthwestern Polytechnical UniversityXi'an 710072China MIIT Key Laboratory of Dynamics and Control of Complex Systems Northwestern Polytechnical UniversityXi'an 710072China School of Aeronautics Northwestern Polytechnical UniversityXi'an 710072China State Key Laboratory of Structural Analysis Optimization and CAE Software for Industrial EquipmentDalian University of TechnologyDalian 116024China

Auxetic metamaterials,which exhibit the negative Poisson’s ratio(NPR)effect,have found wide applications in many engineering fields.However,their high porosity inevitably weakens their bearing capacity and impact resistance.To improve the energy absorption efficiency of auxetic honeycombs,a novel vertex-based hierarchical star-shaped honeycomb(VSH)is designed by replacing each vertex in the classical star-shaped honeycomb(SSH)with a newly added self-similar sub-cell.An analytical model is built to investigate the Young’s modulus of VSH,which shows good agreement with experimental results and numerical simulations.The in-plane dynamic crushing behaviors of VSH at three different crushing velocities are investigated,and empirical formulas for the densification strain and plateau stress are deduced.Numerical results reveal more stable deformation modes for VSH,attributed to the addition of self-similar star-shaped sub-cells.Moreover,compared with SSH under the same relative densities,VSH exhibits better specific energy absorption and higher plateau stresses.Therefore,VSH is verified to be a better candidate for energy absorption while maintaining the auxetic effect.This study is expected to provide a new design strategy for auxetic honeycombs.

关键词： Vertex-based hierarchical star-shaped honeycomb Auxetic honeycomb Energy absorption Plateau stress Negative Poisson's ratio

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An Improved Method for Approximating the Infinite-Horizon Value Function of the Discrete-Time Switched LQR Problem

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Journal of Systems Science & Complexity 2024年第1期37卷 22-39页

作者： hou Tan LI Yuanlong LIN Zongli Department of Automation Shanghai Jiao Tong UniversityShanghai 200240China Key Laboratory of System Control and Information Processing Ministry of Education of ChinaShanghai 200240China Shanghai Engineering Research Center of Intelligent Control and Management Shanghai 200240China Charles L.Brown Department of Electrical and Computer Engineering University of VirginiaCharlottesvilleVA 22904-4743USA

This paper considers the problem of approximating the infinite-horizon value function of the discrete-time switched LQR problem.In particular,the authors propose a new value iteration method to generate a sequence of monotonically decreasing functions that converges exponentially to the value function.This method facilitates us to use coarse approximations resulting from faster but less accurate algorithms for further value iteration,and thus,the proposed approach is capable of achieving a better approximation for a given computation time compared with the existing methods.Three numerical examples are presented in this paper to illustrate the effectiveness of the proposed method.

关键词： Optimal control switched linear systems switched LQR problem.

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Theoretical study on the stability of nanobubbles and its verification in molecular dynamics simulation

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Particuology 2024年第4期87卷 99-105页

作者： Sheng Mi Chaofeng hou Wei Ge School of Chemical Engineering and Technology Tianjin UniversityTianjin300072China State Key Laboratory of Multiphase Complex Systems Institute of Process EngineeringChinese Academy of SciencesBeijing.100190China School of Chemical Engineering University of Chinese Academy of SciencesBeijing100049China

The stability of vapor nanobubbles in bulk liquid was investigated theoretically and the critical bubble size was derived from macroscale thermodynamic equations,below which the system destabilizes with sharp drop in pressure.This critical size was quantitatively verified in molecular dynamic simulation using the Lennard-Jones model of argon,where stronger attraction between the molecules at lower density is found to contribute most to the drop of system pressure and,as the Laplace pressure on the curved bubble interface fails to balance the pressure difference across the interface,the bubbles become unstable.The theoretical model could be extended to other systems where reliable equations of state and interfacial tension are available.

关键词： Nanobubble Stability Phase diagram Critical size

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Transcriptomic and machine learning analyses identify hub genes of metabolism and host immune response that are associated with the progression of breast capsular contracture

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Genes & Diseases 2024年第3期11卷 427-437页

作者： Yukun Mao Xueying hou Su Fu Jie Luan Breast Plastic and Reconstructive Surgery Center Plastic Surgery HospitalChinese Academy of Medical SciencesPeking Union Medical CollegeBeijing 100144China

Capsular contracture is a prevalent and severe complication that affects the post-operative outcomes of patients who receive silicone breast implants.At present,prosthesis replacement is the major treatment for capsular contracture after both breast augmentation procedures and breast reconstruction following breast cancer surgery.However,the mecha-nism(s)underlying breast capsular contracture remains unclear.This study aimed to identify the biological features of breast capsular contracture and reveal the potential underlying mechanism using RNA sequencing.Sample tissues from 12 female patients(15 breast capsules)were divided into low capsular contracture(LCC)and high capsular contracture(HCC)groups based on the Baker grades.Subsequently,41 lipid metabolism-related genes were identified through enrichment analysis,and three of these genes were identified as candidate genes by SVM-RFE and LASSO algorithms.We then compared the proportions of the 22 types of im-mune cells between the LCC and HCC groups using a CIBERSORT analysis and explored the Cor-relation between the candidate hub features and immune cells.Notably,PRKAR2B was positively correlated with the differentially clustered immune cells,which were M1 macro-phages and follicular helper T cells(area under the ROC=0.786).In addition,the expression of PRKAR2B at the mRNA or protein level was lower in the HCC group than in the LCC group.Potential molecular mechanisms were identified based on the expression levels in the high and low PRKAR2B groups.Our findings indicate that PRKAR2B is a novel diagnostic biomarker for breast capsular contracture and might also influence the grade and progression of capsularcontracture.

关键词： Biomarker Breastcapsular contracture Immune infiltration Machinelearning algorithms PRKAR2B

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