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Semi-empirical Likelihood Confidence Intervals for the Differences of Quantiles with Missing Data

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Acta Mathematica Sinica,English Series 2009年第5期25卷 845-854页

作者： yong song qin Jun Chao ZHANG School of Mathematical Sciences Guangxi Normal University Guilin 541004 P. R. China Department of Mathematics Harbin University Harbin 150086 P. R. China

Detecting population （group） differences is useful in many applications, such as medical research. In this paper, we explore the probabilistic theory for identifying the quantile differences .between two populations. Suppose that there are two populations x and y with missing data on both of them, where x is nonparametric and y is parametric. We are interested in constructing confidence intervals on the quantile differences of x and y. Random hot deck imputation is used to fill in missing data. Semi-empirical likelihood confidence intervals on the differences are constructed.

关键词： empirical likelihood confidence interval quantile missing data hot deck imputation

Estimation for Partially Linear Models with Missing Responses:the Fixed Design Case

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Acta Mathematicae Applicatae Sinica 2014年第2期30卷 447-472页

作者： yong-song qin Ying-hua LI School of Mathematics and Statistics Guangxi Normal University Guilin

Suppose that we have a partially linear model Yi = xiβ ＋ g（ti）＋εi with independent zero mean errors εi, where （xi,ti, i = 1, ... ,n} are non-random and observed completely and （Yi, i = 1,...,n} are missing at random（MAR）. Two types of estimators of β and g（t） for fixed t are investigated： estimators based on semiparametric regression and inverse probability weighted imputations. Asymptotic normality of the estimators is established, which is used to construct normal approximation based confidence intervals on β and g（t）. Results are reported of a simulation study on the finite sample performance of the estimators and confidence intervals proposed in this paper.

关键词： partially linear model fixed design point missing at random confidence interval

Empilrical Likelihood for Non-parametric Regression Models with Missing Responses:Multiple Design Case

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Acta Mathematicae Applicatae Sinica 2011年第1期27卷 1-12页

作者： qing-zhu Lei yong-song qin School of Mathematical Sciences Guangxi Normal University Guilin Guangxi 541004 China

Empirical likelihood （EL） ratio statistic on θ=g（x） is constructed based on the inverse probability weighted imputation approach in a nonparametric regression model Y = g（x）＋ε （x ∈ [0, 1]p） with fixed designs and missing responses, which asymptotically has X1^2 distribution. This result is used to obtain a EL based confidence interval on θ.

关键词： Nonparametric regression empirical likelihood missing at random confidence interval

Empirical Likelihood for Response Differences in Two Linear Regression Models with Missing Data

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Acta Mathematicae Applicatae Sinica 2015年第4期31卷 963-976页

作者： yong-song qin Tao QIU qing-zhu LEI Department of Mathematics Guangxi Normal University Guilin

Oonsider two linear models Xi = U＇β ＋ ei, Yj = V1/2y ＋ ηj with response variables missing at random. In this paper, we assume that X, Y are missing at random （MAR） and use the inverse probability weighted imputation to produce ＇complete＇ data sets for X and Y. Based on these data sets, we construct an empirical likelihood （EL） statistic for the difference of X and Y （denoted as A）, and show that the EL statistic has the limiting distribution of X~, which is used to construct a confidence interval for A. Results of a simulation study on the finite sample performance of EL-based confidence intervals on A are reported.

关键词： linear model inverse probability weighted imputation empirical likelihood missing at random confidence interval

Empirical Likelihood for Quantiles Under Associated Samples

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Acta Mathematicae Applicatae Sinica 2015年第1期31卷 71-80页

作者： Ying-hua LI yong-song qin qing-zhu LEI School of Mathematics and Statistics Guangxi Normal University

The construction of confidence intervals for quantiles of a population under a associated sample is studied by using the blockwise technique. It is shown that the blockwise empirical likelihood （EL） ratio statistic is asymptotically X2-type distributed, which is used to obtain EL-based confidence intervals for quantiles of a population.

关键词： quantile associated sample blockwise empirical likelihood confidence interval

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媚俗表征下电视剧视像文化生态审思

东北师大学报（哲学社会科学版） 2014年第2期 95-99页

作者：宋永琴大连理工大学人文社会科学学部辽宁大连116024

视觉文化表征下,"媚俗"成为必然的审美选择,人们自觉地与图像及图像制造的虚拟世界之间建立起一种精神生存的关系,作为视觉文化传播的重要艺术形态之一,电视剧遭遇着文化批判和审美实现的悖论。"视觉优先"趋势,一方面拓展和提升了电视... 详细信息

视觉文化表征下,"媚俗"成为必然的审美选择,人们自觉地与图像及图像制造的虚拟世界之间建立起一种精神生存的关系,作为视觉文化传播的重要艺术形态之一,电视剧遭遇着文化批判和审美实现的悖论。"视觉优先"趋势,一方面拓展和提升了电视剧艺术的叙述能力和美学感染力;另一方面又制造着一场场"泡沫式"的文化胜景。如何实现感性叙事形式和深层审美价值的契合,已成为电视视像艺术一个突出的文化与美学问题,不仅关系到其叙事话语所承载的价值意义所在,也关系着整个电视剧文化产业的生态发展。

关键词：视觉性媚俗景观视觉范式审美文化

The empirical likelihood goodness-of-fit test for regression model

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Science China Mathematics 2007年第6期50卷 829-840页

作者： Li-xing ZHU, yong-song qin & Wang-li XU Department of Mathematics, Hong Kong Baptist University, Kowloon Tong, Hong Kong, China School of Mathematical Sciences, Guangxi Normal Uinversity, Guilin 541004, China School of Statistics, Renmin University of China, Beijing 100875, China Department of Mathematics Hong Kong Baptist University Kowloon Tong China School of Mathematical Sciences Guangxi Normal Uinversity Guilin China School of Statistics Renmin University of China Beijing China

Goodness-of-fit test for regression modes has received much attention in literature. In this paper, empirical likelihood (EL) goodness-of-fit tests for regression models including classical parametric and autoregressive (AR) time series models are proposed. Unlike the existing locally smoothing and globally smoothing methodologies, the new method has the advantage that the tests are self-scale invariant and that the asymptotic null distribution is chi-squared. Simulations are carried out to illustrate the methodology.

关键词： regression model AR time series models empirical likelihood asymptotic normality goodness-of-fit 62G05 62G20 62G30

Potential role of tanycyte-derived neurogenesis in Alzheimer's disease

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Neural Regeneration Research 2025年第6期20卷 1599-1612页

作者： Guibo Qi Han Tang Jianian Hu Siying Kang song qin Department of Anatomy Histologyand EmbryologySchool of Basic Medical SciencesFudan UniversityShanghaiChina State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science Fudan UniversityShanghaiChina

Tanycytes, specialized ependymal cells located in the hypothalamus, play a crucial role in the generation of new neurons that contribute to the neural circuits responsible for regulating the systemic energy balance. The precise coordination of the gene networks controlling neurogenesis in naive and mature tanycytes is essential for maintaining homeostasis in adulthood. However, our understanding of the molecular mechanisms and signaling pathways that govern the proliferation and differentiation of tanycytes into neurons remains limited. This article aims to review the recent advancements in research into the mechanisms and functions of tanycyte-derived neurogenesis. Studies employing lineage-tracing techniques have revealed that the neurogenesis specifically originating from tanycytes in the hypothalamus has a compensatory role in neuronal loss and helps maintain energy homeostasis during metabolic diseases. Intriguingly,metabolic disorders are considered early biomarkers of Alzheimer's disease. Furthermore,the neurogenic potential of tanycytes and the state of newborn neurons derived from tanycytes heavily depend on the maintenance of mild microenvironments, which may be disrupted in Alzheimer's disease due to the impaired blood–brain barrier ***, the specific alterations and regulatory mechanisms governing tanycyte-derived neurogenesis in Alzheimer's disease remain unclear. Accumulating evidence suggests that tanycyte-derived neurogenesis might be impaired in Alzheimer's disease, exacerbating neurodegeneration. Confirming this hypothesis, however, poses a challenge because of the lack of long-term tracing and nucleus-specific analyses of newborn neurons in the hypothalamus of patients with Alzheimer's disease. Further research into the molecular mechanisms underlying tanycyte-derived neurogenesis holds promise for identifying small molecules capable of restoring tanycyte proliferation in neurodegenerative diseases. This line of investigation could pro

关键词： Alzheimer's disease blood–brain barrier ependymoglial cells hypothalamus metabolic diseases neural stem cells neurogenesis neuroinflammatory diseases neurons tanycyte

Enhancing m^(6)A modification in the motor cortex facilitates corticospinal tract remodeling after spinal cord injury

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Neural Regeneration Research 2025年第6期20卷 1749-1763页

作者： Tian qin Yuxin Jin Yiming qin Feifei Yuan Hongbin Lu Jianzhong Hu yong Cao Chengjun Li Department of Spine Surgery and Orthopedics Xiangya HospitalCentral South UniversityChangshaHunan ProvinceChina Key Laboratory of Organ Injury Aging and Regenerative Medicine of Hunan ProvinceChangshaHunan ProvinceChina National Clinical Research Center for Geriatric Disorders Xiangya HospitalCentral South UniversityChangshaHunan ProvinceChina Department of Sports Medicine Xiangya HospitalCentral South UniversityChangshaHunan ProvinceChina

Spinal cord injury typically causes corticospinal tract disruption. Although the disrupted corticospinal tract can self-regenerate to a certain degree, the underlying mechanism of this process is still unclear. N6-methyladenosine(m^(6)A) modifications are the most common form of epigenetic regulation at the RNA level and play an essential role in biological processes. However, whether m^(6)A modifications participate in corticospinal tract regeneration after spinal cord injury remains unknown. We found that expression of methyltransferase 14 protein(METTL14) in the locomotor cortex was high after spinal cord injury and accompanied by elevated m^(6)A levels. Knockdown of Mettl14 in the locomotor cortex was not favorable for corticospinal tract regeneration and neurological recovery after spinal cord injury. Through bioinformatics analysis and methylated RNA immunoprecipitation-quantitative polymerase chain reaction, we found that METTL14 regulated Trib2 expression in an m^(6)A-regulated manner, thereby activating the mitogen-activated protein kinase pathway and promoting corticospinal tract regeneration. Finally, we administered syringin, a stabilizer of METTL14, using molecular docking. Results confirmed that syringin can promote corticospinal tract regeneration and facilitate neurological recovery by stabilizing METTL14. Findings from this study reveal that m^(6)A modification is involved in the regulation of corticospinal tract regeneration after spinal cord injury.

关键词： corticospinal tract remodeling epigenetic regulations locomotor cortex m^(6)A modification methyltransferase 14 protein(METTL14) mitogen-activated protein kinase neural regeneration spinal cord injury syringin TRIB2