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Spectra of rational orthonormal systems

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Science China Mathematics 2019年第10期62卷 1961-1976页

作者： qiuhui chen Pei Dang Tao Qian Department of Mathematics College of Mathematics and InformaticsSouth China Agricultural UniversityGuangzhou510642China Faculty of Information Technology Macao University of Science and TechnologyMacaoChina Macao Institute of Systems Engineering Macao University of Science and TechnologyMacaoChina

We use the Weyl correspondence approach to investigate the spectral operators of the Laguerre and the Kautz systems. We show that the basic functions in the Laguerre and the Kautz systems are the eigenvectors of modified Sturm-Liouville operators. The results are further generalized to multiple parameters of one complex variable in both the unit disc and the upper half-plane contexts.

关键词： spectral operator Laguerre and Kautz systems TM system Caley transform Heisenberg group Weyl correspondence

Shannon-type sampling for multivariate non-bandlimited signals

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Science China Mathematics 2013年第9期56卷 1915-1934页

作者： chen qiuhui QIAN Tao LI YouFa Cisco School of Informatics Guangdong University of Foreign Studies Department of Mathematics Faculty of Science and TechnologyUniversity of Macao College of Mathematics and Information Sciences Guangxi University

In this paper, starting from a function analytic in a neighborhood of the unit disk and based on Bessel functions, we construct a family of generalized multivariate sinc functions, which are radial and named radial Bessel-sinc (RBS) functions being time-frequency atoms with nonlinear phase. We obtain a recursive formula for the RBS functions in R d with d being odd. Based on the RBS function, a corresponding sampling theorem for a class of non-bandlimited signals is established. We investigate a class of radial functions and prove that each of these functions can be extended to become a monogenic function between two parallel planes, where the monogencity is taken to be of the Clifford analysis sense.

关键词： analytic function Fourier transform radial Bessel-Sinc function Shannon sampling

The construction of generalized B-spline low-pass filters related to possibility density

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Science China Mathematics 2012年第12期55卷 2481-2491页

作者： chen qiuhui LI LuoQing MALONEK Helmuth Cisco School of Informatics Guangdong University of Foreign Studies Guangzhou 510006 China Faculty of Mathematics and Computer Sciences Hubei University Wuhan 430062 China Department of Mathematics University of Aveiro Aveiro 3810-193 Portugal

Starting from piecewise constant functions, a novel family of generalized symmetric B-splines, with realizable ideal low-pass filters, are constructed. The first order generalized B-spline low-pass filter is closely related to functions analytic in a neighborhood of the unit disc and the generalized sinc functions. The properties of this kind of low-pass filters are investigated. The behavior of the generalized B-spline low-pass filter related to normalized Gaussian distribution is considered.

关键词： low-pass filter generalized B-spline analytic function Gaussian distribution

Neuronal apoptosis and interleukin 1-beta converting enzyme expression in the frontal cortex and hippocampus of mice with ischemia/reperfusion injury

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Neural Regeneration Research 2010年第11期5卷 864-867页

作者： Ligang Jiang Xinyu Hu qiuhui chen Jie Wu Guohua Hu Wei Li Lijing Cui Department of Neurology the Second Hospital of Jilin University Changchun 130041 Jilin Province China Department of Neurology Jifin Central Hospital Jilin 132011 Jilin Province China Department of Neurology Hospital Affiliated to Beihua University Jilin 132011 Jilin Province China

BACKGROUND： Interleukin 1β-converting enzyme （ICE） gene expression can induce neuronal apoptosis. However, the dynamic changes in ICE gene expression and its effects on neuronal apoptosis under cerebral ischemia/reperfusion conditions remain unclear. OBJECTIVE： To observe neuronal apoptosis and changes in ICE gene expression in the frontal cortex and hippocampus following ischemia/reperfusion injury. DESIGN, TIME AND SETTING： A randomized, controlled animal study was conducted at the Laboratory of Experimental Animal Center, the Second Hospital of Jilin University and Central Laboratory, the Second Hospital of Jilin University, China, from November 2008 to September 2009. MATERIALS： The ICE gene primer sequence （TaKaPa Co., Dalian, China）, FACScan Flow cytometer （Becton Dickinson, Franklin Lakes, N J, USA）, and Perkin Elmer GeneAmp PCR system 2400 （Perkin Elmer, Waltham, MA, USA） were used in this study. METHODS： A total of 45 healthy, adult, male, Kunming mice were randomly assigned to normal control （n = 5）, sham surgery （n = 5）, and model （n = 35） groups. The mice in the model group were equally and randomly subdivided into seven subgroups according to various reperfusion time points （1 hour, 1,3, 7, 14, 28, and 42 days）. Animal models of ischemia/reperfusion injury were established by bilateral carotid artery ligation in the model group. The mice in the sham surgery group only received saline perfusion and surgery for carotid artery exposure. MAIN OUTCOME MEASURES： Neuronal apoptosis in the frontal cortex and hippocampus of mice was measured using flow cytometry. The time course of ICE mRNA levels in the frontal cortex and hippocampus were quantified using reverse transcription-polymerase chain reaction. RESULTS： Neuronal apoptosis in the frontal cortex and hippocampus peaked at 3 days following ischemia/reperfusion injury （P 〈 0.05）. ICE mRNA expression increased in the frontal cortex at 1 day following ischemia/reperfusion injury （P 〈 0.05）, decreased at 3 day

关键词： ischemia/reperfusion injury cell apoptosis interleukin 1β-converting enzyme brain injury neural regeneration

PARK1 gene mutation of autosomal dominant Parkinson's disease family

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Neural Regeneration Research 2011年第5期6卷 330-334页

作者： Ligang Jiang qiuhui chen Ying Zhang Xinyu Hu Jia Fan Lifeng Liu Rui Guo Yajuan Sun Yizhi Zhang Guohua Hu Department of Neurology Second Hospital of Jilin University Changchun 130041 Jilin Province China Department of Neurology Central Hospital of Jilin Jilin 132011 Jilin Province China Beihua University Jilin 132011 Jilin Province China

Studies have shown that PARK1 gene is associated with the autosomal dominant inheritance of Parkinson＇s disease. PARK1 gene contains two mutation sites, namely Ala30Pro and Ala53Thr, which are located on exons 3 and 4, respectively. However, the genetic loci of the pathogenic genes remain unclear. In this study, blood samples were collected from 11 members of a family with high prevalence of Parkinson＇s disease, including four affected cases, five suspected cases and two non-affected cases. Point mutation screening of common mutation sites on PARK1 gene exon 4 was conducted using PCR, to determine the genetic loci of the causative gene for Parkinson＇s disease. Gene identification and sequencing results showed that a T base deletion mutation was observed in the PARK1 gene exon 4 of all 11 collected samples. It was confirmed that the PARK1 gene exon 4 gene mutation is an important pathogenic mutation for Parkinson＇s disease.

关键词： Parkinson's disease family genetic PARK1 gene mutation neurodegenerative disease

Surface Amendments Can Ameliorate Subsoil Acidity in Tea Garden Soils of High-Rainfall Environments

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Pedosphere 2016年第2期26卷 180-191页

作者： WANG Lei Clayton R. BUTTERLY chen qiuhui MU Zhibo WANG Xia XI Yunguan ZHANG Jibing XIAO Xingji Nanjing Institute of Environmental Sciences Ministry of Environmental Protection Nanjing 210032 China State Key Laboratory of Soil and Sustainable Agriculture Institute of Soil Science Chinese Academy of Sciences Nanjing 210008 China AgriBio Centre for Agri-Bioscience La Trobe University Melbourne VIC 3086 Australia Suzhou Xiangcheng District Environmental Monitoring Station Suzhou 215100 China

Strongly acidic soils （pH 〈 5.0） are detrimental to tea （Camellia sinensis） production and quality. Little information exists on the ability of surface amendments to ameliorate subsoil acidity in the tea garden soils. A 120-d glasshouse column leaching experiment was conducted using commonly available soil ameliorants. Alkaline slag （AS） and organic residues, pig manure （PM） and rapeseed cake （RC） differing in ash alkalinity and C/N ratio were incorporated alone and in combination into the surface （0-15 cm） of soil columns （10 cm internal diameter x 50 cm long） packed with soil from the acidic soil layer （15-30 cm） of an Ultisol （initial pH -- 4.4）. During the 120-d experiment, the soil columns were watered （about 127 mm over 9 applications） according to the long-term mean annual rainfall （1 143 mm） and the leachates were collected and analyzed. At the end of the experiment, soil columns were partitioned into various depths and the chemical properties of soil were measured. The PM with a higher C/N ratio increased subsoil pH, whereas the RC with a lower C/N ratio decreased subsoil pH. However, combined amendments had a greater ability to reduce subsoil acidity than either of the amendments alone. The increases in pH of the subsoil were mainly ascribed to decreased base cation concentrations and the decomposition of organic anions present in dissolved organic carbon （DOC） and immobilization of nitrate that had been leached down from the amended layer. A significant （P 〈 0.05） correlation between alkalinity production （reduced exchangeable acidity - N-cycle alkalinity） and alkalinity balance （net alkalinity production - N-cycle alkalinity） was observed at the end of the experiment. Additionally, combined amendments significantly increased （P ~ 0.05） subsoil cation concentrations and decreased subsoil A1 saturation （P 〈 0.05）. Combined applications of AS with organic amendments to surface soils are effective in reducing subsoil acidity in high-rainfall areas. Further i

关键词： Al saturation leaching nitrate organic amendments organic anions pH soil acidity soil alkalinity

全球视野下的稳增长——第二次世界大战以来的增长目标与政府支出

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经济学（季刊） 2021年第2期20卷 405-426页

作者：陈邱惠徐现祥中山大学岭南学院广东省广州市510275

本文从政府支出切入,考察全球视野下的稳增长。本文在理论上贡献识别稳增长力度的方法,在实证上利用手工收集的全球增长目标数据进行检验。本文发现,当需要稳增长时,增长目标每增加1个百分点,政府支出平均增加1.148个百分点。这个发现... 详细信息

本文从政府支出切入,考察全球视野下的稳增长。本文在理论上贡献识别稳增长力度的方法,在实证上利用手工收集的全球增长目标数据进行检验。本文发现,当需要稳增长时,增长目标每增加1个百分点,政府支出平均增加1.148个百分点。这个发现是稳健的。本文发现稳增长的三个特征:在支出结构上,稳增长增加经济事务支出;在资金来源上,稳增长依靠政府经常性收入;在时间维度上,稳增长具有暂时性。本文的发现表明稳增长是全球性现象。

关键词：经济增长增长目标政府支出

A survey of public needs for government information service in libraries

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Chinese Journal of Library and Information Science 2014年第1期7卷 46-56页

作者： Yunpeng QU Huiwei LIANG Lei SA Yumei XU Wenjie DUN Rongrong ZHAO qiuhui chen National Library of China

Purpose:This paper describes a comprehensive user survey carried out in China to investigate public needs for government information service in *** is expected to provide insights into the ways to help public libraries meet the user ***/methodology/approach:The paper is founded on a survey among library users,librarians and non-library *** questionnaires were distributed in the National Library of China and 32 provincial public libraries in China and electronic questionnaires were sent to non-library users.A total of 909 valid questionnaires were ***:A lot of attention is paid to policies,laws and regulations relating to common people’s work and lives such as science,technology,education,culture,finance,market supervision,health care,sports,urban construction and environment protection.A wide variety of government information resources is needed and information delivered to users shall be accurate and *** has become the main means of accessing government information and mobile phones the preferred Web access channel,while printed materials are considered important information *** need assistance and training in the use of library information resources and *** limitations:The sample was limited to respondents from provincial-level public libraries,but city and county-level library users were not *** implications:The survey results are beneficial for the Chinese public libraries to design service programs and improve their ***/value:The paper is one of the comprehensive surveys on public needs for government information service in the Chinese libraries and some of die findings will be of wider interest for other libraries.

关键词： Public needs Public library Government information service China

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经济增长目标、税收特惠政策与资源配置

南开经济研究 2023年第4期 62-80页

作者：陈邱惠杭静徐现祥中山大学岭南学院 510275

现有研究表明,经济增长目标既可引领经济增长,又会加剧资源错配。对此,本文提出一个逻辑自洽的解释:特惠政策。在理论上,本文证明当政府资源有限时,为了最大化辖区产出,政府采取偏向大企业的税收特惠政策来吸引流动性要素,从而增加辖区... 详细信息

现有研究表明,经济增长目标既可引领经济增长,又会加剧资源错配。对此,本文提出一个逻辑自洽的解释:特惠政策。在理论上,本文证明当政府资源有限时,为了最大化辖区产出,政府采取偏向大企业的税收特惠政策来吸引流动性要素,从而增加辖区产出并加剧要素错配。在实证上,本文利用1998—2013年中国工业企业数据库和省级增长目标数据,实证发现:增长目标每增加1个百分点,税收减免特惠程度显著提高3.2%;税收特惠政策偏向大企业,而不是偏向中小企业;在增长目标激励下,税收特惠政策加剧地区内的资本和劳动力错配。本文揭示了地方政府为达成经济增长目标而实施特惠政策的普遍做法,表明新时代发展需要转向普惠政策,提高发展质量。

关键词：增长目标税收特惠政策要素错配