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Science China Mathematics 2013年第9期56卷 1895-1913页

作者： LIU Yu HUANG JiZheng dong jianfeng School of Mathematics and Physics University of Science and Technology Beijing College of Sciences North China University of Technology Department of Mathematics Shanghai University

Let X be an RD-space. In this paper, the authors establish the boundedness of the commutator Tbf = bTf-T(bf) on Lp , p∈(1,∞), where T is a Calderón-Zygmund operator related to the admissible function ρ and b∈BMOθ(X)BMO(X). Moreover, they prove that Tb is bounded from the Hardy space H1ρ(X) into the weak Lebesgue space L1weak(X). This can be used to deal with the Schrdinger operators and Schrdinger type operators on the Euclidean space Rn and the sub-Laplace Schrdinger operators on the stratified Lie group G.

关键词： commutator spaces of homogeneous type stratified Lie groups admissible function Hardy space reverse Ho¨lder inequality Riesz transform Schr¨odinger operators

An all-dielectric chiral metasurface with circular dichroism and asymmetric transmission characteristics

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Optoelectronics Letters 2024年第9期20卷 537-542页

作者： WU Qihang SHI Zhuolin HE Jinglin dong jianfeng Department of Electronic Information Science and Technology Ningbo UniversityNingbo 31521lChina

This paper designs an all-dielectric metasurface with tunable chiral properties in the near-infrared range,whose working wavelength is 1250-2200 *** metasurface exhibits circular dichroism(CD)and asymmetric transmission(AT)characteristics for circularly polarized *** metasurface is a double-layer structure composed of Ge_(2)Sb_(2)Se_(4)Te_(1)(GSST).

关键词： circular dielectric chiral

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Robust video question answering via contrastive cross-modality representation learning

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Science China(Information Sciences) 2024年第10期67卷 211-226页

作者： Xun YANG Jianming ZENG Dan GUO Shanshan WANG jianfeng dong Meng WANG School of Information Science and Technology University of Science and Technology of China Institute of Artificial Intelligence Hefei Comprehensive National Science Center School of Computer Science and Information Engineering Hefei University of Technology Institutes of Physical Science and Information Technology Anhui University School of Computer Science and Technology Zhejiang Gongshang University

Video question answering(VideoQA) is a challenging yet important task that requires a joint understanding of low-level video content and high-level textual semantics. Despite the promising progress of existing efforts, recent studies revealed that current VideoQA models mostly tend to over-rely on the superficial correlations rooted in the dataset bias while overlooking the key video content, thus leading to unreliable results. Effectively understanding and modeling the temporal and semantic characteristics of a given video for robust VideoQA is crucial but, to our knowledge, has not been well investigated. To fill the research gap, we propose a robust VideoQA framework that can effectively model the cross-modality fusion and enforce the model to focus on the temporal and global content of videos when making a QA decision instead of exploiting the shortcuts in datasets. Specifically, we design a self-supervised contrastive learning objective to contrast the positive and negative pairs of multimodal input, where the fused representation of the original multimodal input is enforced to be closer to that of the intervened input based on video perturbation. We expect the fused representation to focus more on the global context of videos rather than some static keyframes. Moreover, we introduce an effective temporal order regularization to enforce the inherent sequential structure of videos for video representation. We also design a Kullback-Leibler divergence-based perturbation invariance regularization of the predicted answer distribution to improve the robustness of the model against temporal content perturbation of videos. Our method is model-agnostic and can be easily compatible with various VideoQA backbones. Extensive experimental results and analyses on several public datasets show the advantage of our method over the state-of-the-art methods in terms of both accuracy and robustness.

关键词： video question answering cross-modality fusion contrastive learning cross-media reasoning

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Ultrastructural changes of rat cortical neurons following ligustrazine intervention for cerebral ischemia/reperfusion injury

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Neural Regeneration Research 2008年第1期3卷 41-43页

作者： Hui Zhang jianfeng dong Qiuzhen Zhao Wen Song Aihua Bo Department of Anatomy and Electron Microscopy Hebei North University Zhangjiakou 075029 Hebei Province China

BACKGROUND： Ligustrazine can reduce the production of free radicals and the content of malonaldehyde, and improve the enzymatic activity of adenosine-triphosphate in cerebral anoxia. It also can increase the expression of heat shock protein-70 and Bcl-2, thus alleviating brain tissue injury caused by cerebral ischemia/reperfusion. This study aimed to address the question of whether ligustrazine can protect the membrane structure of neurons. OBJECTIVE： To establish rat models of cerebral ischemia/reperfusion, observe the membrane structure and main organelles of neurons with electron microscope after ligustrazine intervention, and to analyze the dose-dependent effects of ligustrazine on neuronal changes. DESIGN： A randomized controlled study. SETTING： Department of Anatomy Research and Electron Microscopy, Hebei North University. MATERIALS： Forty Wistar rats of SPS grade, weighing 180-250 g and equal proportion of female and male, were provided by Hebei Medical University Animal Center （No. 060126）. The ligustrazine injection （40 g/L, No. 05012） was produced by Beijing Yongkang Yaoye. LKB4 Ultramicrotome was purchased from LKB Company in Sweden. JEM100CXII electron microscope was purchased from JEOL in Japan. METHODS： The experiment was performed in the Laboratory of the Department of Anatomy and Electron Microscopy, Hebei North University from June to August 2006. （1） Wistar rats were allowed to adapt for 3 days, and were then randomly divided into four groups, according to the numeration table method： normal group, model group, low-dose ligustrazine group, and high-dose ligustrazine group. There were 10 rats in each group. （2）Rats in the model group, low-dose ligustrazine group, and high-dose ligustrazine group underwent cerebral ischemia/reperfusion model, according to Bannister＇s method. The carotid artery was opened for reperfusion after 90 minutes of cerebral ischemia. Samples were collected from the cerebral cortex after 24 hours. Animals from the ligustrazine

关键词： cerebral ischemia/reperfusion ligustrazine neuron ultrastructure electron microscope

MULTI-MODE NETWORK ANALYSIS FOR DISCONTINUITIES IN PARALLEL-PLATE WAVEGUIDES PARTIALLY FILLED WITH MULTI CHIRAL RODS

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Journal of Electronics(China) 2006年第5期23卷 748-752页

作者： dong jianfeng Xu Shanjia Institute of Optical Fiber Commun ＆ Network Tech. Ningbo Univ. Ningbo 315211 China Dept of Electronic Eng ＆ Info. Sci. Univ. ofSci. ＆ Teeh. of China Hefei 230027 China

The reflection and transmission characteristics of the guided modes in parallel-plate waveguides partially filled with one or multi chiral rods have been investigated by a method, which combines the multi- mode network theory with a rigorous mode matching procedure. The formulas of the reflection and transmis- sion coefficient matrix are derived. The numerical results for different cases are presented and have indicated that the chirality parameters and the geometrical dimensions of the chiral rods have significant influence on the reflection and transmission characteristics of the guided modes.

关键词： Chiral medium Parallel-plate waveguide Discontinuity Multimode network Mode matching

Long noncoding RNA LINC01106 promotes lung adenocarcinoma progression via upregulation of autophagy

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Oncology Research 2025年第1期33卷 171-184页

作者： GENGYUN SUN YIPING ZHENG jianfeng CAI JIE GAO LIE dong XIANGBIN ZHANG YINGHUI HUANG Department of Respiratory and Critical Care Medicine The First Affiliated Hospital of Anhui Medical UniversityHefei230022China Department of Respiratory and Critical Care Medicine Nanping First Hospital Affiliated to Fujian Medical UniversityNanping353006China

Background:Long noncoding RNA,LINC01106 exhibits high expression in lung adenocarcinoma(LUAD)tumor tissues,but its functional role and regulatory mechanism in LUAD cells remain ***:LINC01106 expression was analyzed in LUAD tissues and its functional impact on LUAD cells was *** cells were silenced with sh-LINC01106 and injected into nude mice to investigate tumor *** downstream transcription factors and molecular mechanism were determined using the Human transcription factor database(TFDB)database and Gene Expression Profiling Interactive Analysis(GEPIA)***,the impact of linc01106 on autophagy was analyzed by determining the expression of autophagy-related genes(ATGs)in LUAD ***:Our results showed that LINC01106 exhibited upregulation in both LUAD tissues and cell *** silencing of LINC01106 demonstrated a suppressive effect on tumorigenesis in a xenograft mouse model of ***,LINC01106 was found to recruit TATA-binding protein-associated factor 15(TAF15),an RNA-binding protein,thereby enhancing the mRNA stability of TEA domain transcription factor 4(TEAD4).In turn,TEAD4 served as a transcription factor that bound to the LINC01106 promoter and regulated its *** assays indicated that LINC01106 promoted autophagy in LUAD cells by upregulating the expression of autophagy-related genes(ATGs).The silencing of LINC01106 in LUAD cells inhibited autophagy,and cell proliferation,and promoted apoptosis,which all were effectively reversed by ATG5 ***:Overall,LINC01106,transcriptionally activated by TEAD4,interacts with TAF15 to promote the stability of TEAD4 and upregulates the expression of ATGs,promoting malignancy of LUAD cells.

关键词： LINC01106 TAF15 TEAD4 ATG5 Lung adenocarcinoma(LUAD) Non-small cell lung cancer(NSCLC)

An Empirical Study on the Correlation Between Cruising Motivation and Cruising Intention

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Journal of Tourism and Hospitality Management 2014年第3期2卷 114-123页

作者： Guo Yingzhi Hu Tian Huang jianfeng dong Kun Fudan University Shanghai China

The cruising market is booming in China, and both motivation and intention are the most important aspects in the field of study on the cruising passengers＇ behaviors. The research purpose of this paper is to identify the motivation factors of the cruising passengers in China and their impact on the cruising intention. Based on the push-pull model, this paper indentified the motivation factors, including intrinsic ones and extrinsic ones, and put forward the research model. The intrinsic motivation factors include relaxation, socialization, family bonding, and social recognition, whereas the extrinsic motivation factors include entertainment and ashore tour. Having collected data through survey and analyzed them by the statistic methodology, this paper found that the motivation factors of relaxation, family bonding, entertainment, and ashore tour have a positive impact on the cruising intention, and the impact of relaxation is significant. By contrast, the motivation factors of socialization and social recognition are not positively associated with the cruising intention.

关键词： cruising passengers motivation cruising intention correlation analysis

Preparation of ZrSiO_4 Nano-powders by Micro-wave Hydrothermal Process

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稀有金属材料与工程 2011年第S3期40卷 202-205页

作者： Liu Dawei, Wang Feng, Zhu jianfeng, Li dong Key Laboratory of Auxiliary Chemistry & Technology for Chemical Industry, Ministry of Education, Shaanxi University of Science and Technology, Xi’an 710021, China Shaanxi Univ Sci & Technol Key Lab Auxiliary Chem & Technol Chem Ind Minist Educ Xian 710021 Peoples R China

High purity ZrSiO4 powders were prepared using zirconium oxychloride and tetraethoxysilane as raw materials by the microwave-hydrothermal method at 160-200 ℃ for 30 min, in which NaF was added as mineralizer to promote the crystallization of zircon. The phase composition and microstructure of synthesized ZrSiO4 powders were investigated in detail. The results show that: the microwave-hydrothermal method greatly reduces the synthesis temperature of ZrSiO4 to 160 ℃, 30 min. The synthesized ZrSiO4 powders have small particle size and high stability up to 950 ℃. The synthesis mechanism of ZrSiO4 by microwave hydrothermal s process was also discussed.

关键词： microwave-hydrothermal method ZrSiO4 powders reaction mechanism

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超表面的电磁特性研究进展

材料导报 2016年第13期30卷 49-54页

作者：周霞汪会波董建峰宁波大学信息科学与工程学院宁波315211

超表面由于具有自然界不存在的独特电磁特性而引起了人们极大的兴趣,它是占有更少物理空间,提供更小损耗,更容易被制造的一类超材料。简要介绍了超表面的概念和背景,并着重阐述了超表面结构在微波段、太赫兹波段以及光频段的模拟计算及... 详细信息

超表面由于具有自然界不存在的独特电磁特性而引起了人们极大的兴趣,它是占有更少物理空间,提供更小损耗,更容易被制造的一类超材料。简要介绍了超表面的概念和背景,并着重阐述了超表面结构在微波段、太赫兹波段以及光频段的模拟计算及实验研究进展。这些超表面在微波、光波、光电子器件中具有潜在的应用价值。

关键词：超表面超材料不对称传输圆极化波线极化波

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新型货币政策、企业融资与债务资金配置

财经科学 2023年第5期 20-33页

作者：康书隆董剑峰东北财经大学金融学院

本文借助2015年2月中国人民银行发布《关于印发的通知》(以下简称“指引”)的准自然实验,考察抵押品框架下新型货币政策对企业融资与债务资金配置的影响。研究发现,政策实施导致债券被纳入抵押品的上市企业的负债率显著提高,企业的融资... 详细信息

本文借助2015年2月中国人民银行发布《关于印发的通知》(以下简称“指引”)的准自然实验,考察抵押品框架下新型货币政策对企业融资与债务资金配置的影响。研究发现,政策实施导致债券被纳入抵押品的上市企业的负债率显著提高,企业的融资成本显著降低,这有助于提高企业的债务融资能力;企业负债率提高源于银行贷款占比提高,而债券融资比例并未发生显著变化,央行抵押品框架主要通过金融中介而非资本市场发挥作用;在政策效果层面,政策实施能够刺激企业增加投资,与此同时,企业的现金留存与对外金融投资收益亦显著增加,这说明新增融资并未全部转化为投资进入实体经济,存在一定程度的信贷资金漏出效应。为此,政策上应通过提升债券市场的融资效率、提高流动性投放精准度和加强信贷资金用途监管等措施,从而提高新型货币政策对实体经济支持的效率。

关键词：新型货币政策企业融资债务资金配置传导机制