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Nuclear Science and Techniques 2021年第10期32卷 143-155页

作者： Yu-Chuan Guo zi-lin Su Ze-Guang Li Kan Wang Department of Engineering Physics Tsinghua UniversityBeijing 100084China

A suitable model for high-temperature heat pipe startup is a prerequisite to realizing the numerical simula-tion for the heat pipe cooled reactor startup from the cold *** is required that this model not only describes the transient behavior during the startup period,but also reduces the computing resources of the heat pipe cooled reactor simulation in the simplest *** this study,a simplified model that integrates the two-zone and network models is *** this model,vapor flow in the vapor space,evaporation,and condensation in the vapor–liquid interface are decoupled with heat conduction to achieve a fast calculation of the transient characteristics of the heat *** experimental system for a high-temperature heat pipe was developed to validate the proposed model.A potassium heat pipe was utilized as the experimental *** experiments were performed with differ-ent heating *** with the experimental results,the accuracy of the proposed model was ***,the proposed model can predict the vapor flow,pressure drop,and temperature drop in the vapor *** indicated by the analysis results,the essential requirements for successful startup are also *** heat pipe cannot achieve a successful startup until the heating power satisfies these *** the discussions indicate the capability of the proposed model for the simulation of a high-temperature heat pipe startup from the frozen state;hence,can act as a basic tool for the heat pipe cooled reactor simulation.

关键词： High-temperature heat pipe Startup Two-zone model Network model

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World Journal of Clinical Cases 2021年第22期9卷 6329-6342页

作者： Ya-Jing Sun ling-zi Xu zeng-Hui Ma Yu-Lu Yang Ting-Ni Yin Xiao-Yun Gong zi-lin Gao Yan-ling Liu Jing Liu Peking University Sixth Hospital Peking University Institute of Mental HealthNHC Key Laboratory of Mental Health(Peking University)National Clinical Research Center for Mental Disorders(Peking University Sixth Hospital)Beijing 100191China Quanzhou Children’s and Women’s Hospital Quanzhou 362000Fujian ProvinceChina Department of Mathematics Changzhi Medical CollegeChangzhi 046000Shanxi ProvinceChina

BACKGROUND Health-related risky behaviors generally refer to behaviors that have a negative impact on health and quality of ***-related risky behaviors in adolescents with high-functioning autism(HFA)have not been well understood so *** with HFA may have more health-related risky behaviors than neurotypical *** To investigate health-related risky behaviors and their risk factors with *** This is an observational *** study enrolled 110 adolescents aged 12-19-years-old meeting Diagnostic and Statistical Manual of Mental Disorders 4th edition criteria for *** were recruited from Peking University Sixth *** were also 110 age,sex and nationality matched controls enrolled who came from a public school in Beijing,*** groups completed the Adolescents Health-related Risky Behavior *** tests were carried out for comparison of the Adolescents Health-related Risky Behavior Inventory scores between the two *** recognition,the Inventory of Subjective Life Quality for Child and Adolescent,Chinese Wechsler Intelligence Scale for Children,Wechsler Intelligence Scale for Adult-Chinese Revised,Theory of Mind test and Autism Spectrum Screening Questionnaire were assessed in the autism group to explore factors associated with health-related risky *** regression analysis was conducted to explore the risk factors of health-related risky behaviors in the HFA *** The results showed that the total score of the Adolescents Health-related Risky Behavior Inventory and scores of“aggression and violence,”“suicide and selfinjury,”“health compromising behavior”and“unprotected sex”subscales in the HFA group were significantly higher than those in the control group(Z range-4.197 to-2.213,P<0.05).Among the associated factors,poor emotional experience(B=-0.268,P<0.001),depression(B=-0.321,P<0.001),low score of intelligence(B=-0.032,P=0.042),low score of Theory of Mind test

关键词： High-functioning autism Adolescents Health-related risky behaviors Associated factors Risk factors Cross-sectional study

Proving total correctness and generating preconditions for loop programs via symbolic-numeric computation methods

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Frontiers of Computer Science 2014年第2期8卷 192-202页

作者： Wang lin Min WU Zhengfeng YANG Zhenbing zeng Shanghai Key Laboratory of Trustworthy Computing East China Normal University Shanghai 200062 China College of Mathematics and Information Science Wenzhou University Zhejiang 325035 China Department of Mathematics Shanghai University Shanghai 200444 China

We present a symbolic-numeric hybrid method, based on sum-of-squares （SOS） relaxation and rational vec- tor recovery, to compute inequality invariants and ranking functions for proving total correctness and generating pre- conditions for programs. The SOS relaxation method is used to compute approximate invariants and approximate rank- ing functions with floating point coefficients. Then Gauss- Newton refinement and rational vector recovery are applied to approximate polynomials to obtain candidate polynomials with rational coefficients, which exactly satisfy the conditions of invariants and ranking functions. In the end, several exam- ples are given to show the effectiveness of our method.

关键词： symbolic computation sum-of-squares relax-ation semidefinite programming total correctness precon-dition generation.

Anti-programmed cell death ligand 1-based immunotherapy in recurrent hepatocellular carcinoma with inferior vena cava tumor thrombus and metastasis:Three case reports

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World Journal of Clinical Cases 2021年第21期9卷 5988-5998页

作者： Shao-Ru Liu Qing Yan Hao-Ming lin Guang-zi Shi Yi Cao Hong zeng Chao Liu Rui Zhang Guangdong Provincial Key Laboratory of Malignant Tumor Epigenetics and Gene Regulation and Department of Biliary-Pancreatic Surgery Sun Yat-sen Memorial HospitalSun Yat-sen UniversityGuangzhou 510288Guangdong ProvinceChina Department of Radiology Sun Yat-sen Memorial HospitalSun Yat-sen UniversityGuangzhou 510120Guangdong ProvinceChina Department of Emergency Sun Yat-sen Memorial HospitalSun Yat-sen UniversityGuangzhou 510120Guangdong ProvinceChina Department of Pathology Sun Yat-sen Memorial HospitalSun Yat-sen UniversityGuangzhou 510120Guangdong ProvinceChina

BACKGROUND Recurrent hepatocellular carcinoma(HCC)with inferior vena cava tumor thrombus is a great challenge for oncologists and has a poor *** date,the safety and efficacy of programmed cell death ligand 1(PD-L1)inhibitors are still *** SUMMARY A 59-year-old male was identified as having a tumor thrombus in the inferior vena cava 3 years after *** patient underwent a second surgery and adjuvant ***,the level of alpha-fetoprotein was elevated after 2 mo,and lung metastases and mediastinal lymph node metastases were *** expression of PD-L1 in HCC and inferior vena cava tumor thrombus tissues was analyzed by ***,the patient received atezolizumab *** level of alpha-fetoprotein dropped to normal,the mediastinal lymph node metastases decreased in size and the lung metastases disappeared after 3 mo of *** patient had no signs of recurrence at 21 mo of follow-up.A 60-year-old male underwent left hepatic tumor resection,inferior vena cava incision and thrombus removal,followed by regular *** patient developed lung and splenic metastases after *** was used for six courses,and the splenic metastasis shrank,after which splenectomy was *** patient continued to receive pembrolizumab for thirteen courses,and the lung metastases showed no progression.A 34-year-old male was diagnosed with liver cancer with inferior vena cava tumor *** patient underwent right hepatectomy and received tislelizumab for three *** is still receiving immunotherapy and in good *** Anti-PD-L1 therapy in HCC patients with inferior vena cava tumor thrombus and metastasis is associated with relatively good patient outcomes.

关键词： Recurrent hepatocellular carcinoma Inferior vena cava tumor thrombus Metastasis Programmed cell death ligand 1 Immunotherapy Case report

Magnetic two-dimensional chromium trihalides:structure,properties and modulation

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Rare Metals 2022年第9期41卷 2921-2942页

作者： Biao Zhang Yi zeng zi-Jing Zhao Da-Ping Qiu Teng Zhang Yang-Long Hou Beijing Innovation Centre for Engineering Science and Advanced Technology Beijing Key Laboratory for Magnetoelectric Materials and DevicesSchool of Materials Science and EngineeringPeking UniversityBeijing100871China

The unique optical and electrical properties of two-dimensional(2D)materials provide a platform for novel van der Waals(vdW)heterojunction devices but the investigation of 2D magnetism is still ***,the emergence of long-range magnetic order atomically thin crystals expands 2D family,providing possibilities for the study of low-dimensional spin behavior and novel spintronics *** a specific member of magnetic van der Waals family,chromium trihalides(CrX_(3),X=Cl,Br,I)stimulated intensive interests on account of the newfangled magnetic *** this review,we briefly introduce the crystal structures,magnetism of the bulk and synthetic methods of 2D CrX_(3).Subsequently,the physical properties in atomically thin limit and magnetism manipulated by external field are ***,some novel physical phenomena in CrX_(3) heterojunctions are ***,the challenges and future directions are *** focus on the intriguing physical phenomena in 2D magnetic CrX_(3) by combining related theoretical calculations and experimental results,providing a perspective on these emerging materials.

关键词： Two-dimensional materials Chromium trihalides Two-dimensional magnetism Heterojunction

Tendencies of alloyed engineering in BiOX-based photocatalysts:a state-of-the-art review

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Rare Metals 2024年第4期43卷 1488-1512页

作者： Yan-Dong Sun Chao zeng Xue Zhang zi-Qi Zhang Bo Yang Sheng-Qi Guo Tianjin Key Laboratory of Clean Energy and Pollutant Control School of Energy and Environmental EngineeringHebei University of TechnologyTianjin300401China State-Province Joint Engineering Laboratory of Zeolite Membrane Materials Institute of Advanced MaterialsCollege of Chemistry and Chemical EngineeringJiangxi Normal UniversityNanchang330022China Anhui Province Key Laboratory of Pollutant Sensitive Materials and Environmental Remediation School of Physics and Electronic InformationAnhui Province Industrial Generic Technology Research Center for Alumics MaterialsHuaibei Normal UniversityHuaibei235000China

Energy-saving and environmentally friendly photocatalysis has emerged as a popular research area in response to issues with energy scarcity and environmental *** to the unique layer-like structure,BiOX(Cl,Br,I)is frequently used in ***,inherent flaws in BiOX,such as an inappropriate band gap and low carrier separation efficiency,restrict its capacity for *** to the tunable grouping layer,alloying engineering is employed to optimize the intrinsic properties of BiOX and alloyed BiOX becomes a promising photocatalytic *** review describes the structure of BiOX,where tunable halogen layers provide favorable conditions for the implementation of alloying engineering to improve intrinsic *** article compares the effects and mechanisms of alloying engineering on the optimization of the energy band structure and carrier behavior of BiOX,and lists various modification methods used to improve the optimization of the intrinsic properties by alloying engineering,including defect engineering,morphology control as well as the synergy between alloying and other modification methods(bismuth-rich strategies,cation doping,construction of heterojunctions and plasma resonance effects).Subsequently,applications of alloyed BiOX in energy and environmental fields are summarized,including contaminant degradation,antibacterial,CO_(2)reduction,nitrogen fixation and organic ***,we summarize the current challenges and future directions of alloyed *** is expected that this work will provide guidance and assistance for an in-depth study and understanding of the mechanisms of alloying engineering to optimize intrinsic properties and design alloyed BiOX with higher photocatalytic activity.

关键词： Bismuth oxyhalide Photocatalytic Alloyed engineering Microstructural regulation Application

External penetrating laryngeal trauma caused by a metal fragment:A Case Report

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World Journal of Clinical Cases 2022年第4期10卷 1394-1400页

作者： zi-Han Qiu Jin zeng Qiang Zuo Zhong-Qi Liu Department of Otolaryngology-Head and Neck Surgery the First Affiliated Hospital of Shantou University Medical CollegeShantou 515041Guangdong ProvinceChina Department of Otolaryngology Head and Neck Surgery Peking University Third HospitalBeijing 100191China

BACKGROUND Although external penetrating laryngeal trauma is rare in the clinic,such cases often result in a high mortality *** early recognition of injury,protection of the airway,one-stage laryngeal reconstruction with miniplates and interdisciplinary cooperation are important in the treatment of such *** SUMMARY A 58-year-old male worker sustained a penetrating injury in the left *** computed tomography scanning at a local hospital,he was transferred to our hospital,where he underwent tracheotomy,neck exploration,extraction of the foreign object,debridement and repair of the thyroid cartilage using titanium *** endo laryngeal stent was inserted,which was removed 12 days *** patient recovered well and his voice rapidly improved after *** Penetrating laryngeal trauma is *** successfully treated a patient with early laryngeal reconstruction and management by interdisciplinary cooperation.

关键词： Laryngeal trauma Reconstructive operation Miniplate Multi-discipline cooperation Computed tomography Case report

Insights on the possibility of SARS-CoV-2 transmission through the eyes

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International Journal of Ophthalmology(English edition) 2022年第11期15卷 1857-1863页

作者： Rui Zhu zi-Yan Yu lin Han Department of Ophthalmology the Fourth Affiliated Hospital of China Medical UniversityShenyang 110005Liaoning ProvinceChina Eye Hospital of China Medical University Shenyang 110005Liaoning ProvinceChina Key Lens Research Laboratory of Liaoning Province Shenyang 110005Liaoning ProvinceChina China Medical University Shenyang 110122Liaoning ProvinceChina

A novel coronavirus, named severe acute respiratory syndrome coronavirus 2(SARS-Co V-2 or 2019-nCOV), causing coronavirus disease 2019(COVID-19), has rapidly spread to most countries and regions worldwide since it broke out at the end of 2019. Epidemic of the virus produces a tremendous pressure on the global health systems. With progressive insight into SARS-Co V-2, the role of eye tissue has attracted wide attention in the spread of COVID-19. Whether SARS-Co V-2 can enter the human body through eyes and cause infection? The fact that unprotected exposure of the eyes to 2019-n Co V might have allowed the virus to infect the body implies that 2019-n COV can invade eye tissue and set foot in organism. Facing the severe challenge of preventing spread of the COVID-19, combined with the high-risk environment of ophthalmology, it is crucial to investigate ocular tropism of coronavirus. This paper explores the possibility of coronavirus transmission through the eye from aspects of probable mechanisms, clinical cases, detection of coronavirus;and puts forward precautions for ophthalmologists and nurses. Consequently, this review reveals our understanding of ocular tropism of coronavirus and contributes to determining risk of ocular transmission, raising awareness of necessary eye protection among medical workers and reducing further prevalence of SARS-Co V-2.

关键词： coronavirus SARS-CoV-2 ocular conjunctivitis

Data driven composite shape descriptor design for shape retrieval with a VoR-Tree

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Applied Mathematics(A Journal of Chinese Universities) 2018年第1期33卷 88-106页

作者： WANG zi-hao lin Hong-wei XU Chen-kai School of Mathematical Science State Key Lab.of CAD&CG Zhejiang University

We develop a data driven method(probability model) to construct a composite shape descriptor by combining a pair of scale-based shape descriptors. The selection of a pair of scale-based shape descriptors is modeled as the computation of the union of two events, i.e.,retrieving similar shapes by using a single scale-based shape descriptor. The pair of scale-based shape descriptors with the highest probability forms the composite shape descriptor. Given a shape database, the composite shape descriptors for the shapes constitute a planar point set.A VoR-Tree of the planar point set is then used as an indexing structure for efficient query operation. Experiments and comparisons show the effectiveness and efficiency of the proposed composite shape descriptor.

关键词： shape descriptor shape retrieval shape analysis data-driven model

Numerical Approaches to Identification of Characteristic Soil Layers in an Urban Environment

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Pedosphere 2008年第3期18卷 335-343页

作者： YUAN Da-Gang ZHANG Gan-lin GONG zi-Tong State Key Laboratory of Soil and Sustainable Agriculture Institute of Soil Science Chinese Academy of SciencesNanjing 210008 （China） Graduate School of the Chinese Academy of Sciences Beijing 100049 （China） College of Resource and Environmental Sciences Sichuan Agricultural University Ya＇an 625014 （China）

Pedogenetic soil horizons are one of the fundamental building blocks of modern soil classification; however, in soils of urban areas which are often strongly disturbed by human activities, horizons are difficult to distinguish but substitutive morphological layers may be identified. To identify the characteristic soil layers in an urban environment, 224 soil layers of 36 in-situ pedons were examined and described in urban and suburban Nanjing, and 27 variables were extracted for multivariate analysis. Three groups and six subdivisions were identified by TwoStep cluster analysis combined with hierarchical cluster analysis based on factor scores. Soil forming factors and soil forming processes could be interpreted from the principal component analysis （PCA） of variables, cluster analysis of soil layers, and discriminant analysis of soil layer groups and their subdivisions. Parent materials, moisture regimes, organic matter accumulation, and especially nutrient accumulation were the main causes of characteristic soil layer formations. The numerical approaches used in this study were useful tools for characteristic soil layer identification of urban soils.

关键词： characteristic soil layer multivariate analysis numerical soil classification urban soils