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Robust Error Density Estimation in Ultrahigh Dimensional Sparse Linear Model

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Acta Mathematica Sinica,English Series 2022年第6期38卷 963-984页

作者： Feng ZOU Heng Jian CUI School of Mathematical Sciences Capital Normal UniversityBeijing 100048P.R.China

This paper focuses on error density estimation in ultrahigh dimensional sparse linear model,where the error term may have a heavy-tailed ***,an improved two-stage refitted crossvalidation method combined with some robust variable screening procedures such as RRCS and variable selection methods such as LAD-SCAD is used to obtain the submodel,and then the residual-based kernel density method is applied to estimate the error density through LAD *** given conditions,the large sample properties of the estimator are also ***,we explicitly give the relationship between the sparsity and the convergence rate of the kernel density *** simulation results show that the proposed error density estimator has a good performance.A real data example is presented to illustrate our methods.

关键词： Ultrahigh dimensional sparse linear model robust density estimation refitted crossvalidation method asymptotic properties

Functional role of ATM in the cellular response to DNA damage

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Frontiers of Chemical Science and Engineering 2011年第2期5卷 179-187页

作者： Ming LIU Wenxiang HU College of Life Science Capital Normal UniversityBeijing 100048China Institute of Physical Organic and Medicinal Chemistry Capital Normal UniversityBeijing 100048China

Ataxia-telangiectasia mutated(ATM)plays a key role in regulating the cellular response to ionizing *** tumor-suppressor gene ATM,mutations in which cause the human genetic disease ataxia telangiecta-sia,encodes a key protein kinase that controls the cellular response to double-stranded *** of ATM results in phosphorylation of many downstream targets that modulate numerous damage response pathways,most notably cell cycle ***,we highlight some of the new developments in theﬁeld in our understanding of the mechanism of activation of ATM and its signaling pathways,explore whether DNA double-strand breaks are the sole activators of ATM and ATM-dependent signaling pathways,and address some of the prominent,unanswered questions related to ATM and its *** scope of this article is to provide a brief overview of the recent literature on this subject and to raise questions that could be addressed in future studies.

关键词： ataxia-telangiectasia mutated(ATM) cell cycle checkpoint DNA damage signalling transduction

Help from space:grant-free massive access for satellite-based IoT in the 6G era

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Digital Communications and Networks 2022年第2期8卷 215-224页

作者： Neng Ye Jihong Yu Aihua Wang Rongrong Zhang School of Information and Electronics Beijing Institute of TechnologyBeijing100081China Information Engineering College Capital Normal UniversityBeijing100048China

The Sixth-Generation(6G)standard for wireless communications is expected to realize ubiquitous coverage for massive Internet of Things(IoT)networks by ***-based communications are recognized as a highly promising technical enabler to satisfy IoT service requirements in the 6G *** study analyzes multiple access technologies,which are essential for the effective deployment of satellite-based ***,we thoroughly investigate the existing research related to massive access,including information-theory considerations as well as Non-Orthogonal Multiple Access(NOMA)and Random Access(RA)***,we explore the influence of the satellite transmission environment on multiple access *** on this study,a Non-orthogonal Massive Grant-Free Access(NoMaGFA)scheme,which reaps the joint benefits of RA and NOMA,is proposed for asynchronous transmissions in satellite-based IoT to achieve improved system throughput and enhance the system robustness under varying ***,we identify some important and interesting future developments for satellite-based IoT,including waveform design,transceiver design,resource allocation,and artificial intelligence-enhanced design.

关键词： Internet of things Satellite communications Non-orthogonal multiple access Random access Asynchronous transmission

A new fossil genus of Mesosciophilidae(Diptera,Nematocera) with two new species from the Middle Jurassic of Inner Mongolia,China

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Progress in Natural Science:Materials International 2009年第12期19卷 1837-1841页

作者： Tingting Li,Dong Ren~* College of Life Science,capital normal university,beijing 100048,China [a]College of Life Science Capital Normal University Beijing 100048 China

A new genus within the family Mesosciophilidae,Jurasciophila ***.,with two new species,J,curvula *** *** *** *** ***.,are described and *** are established based on fossil specimens with bodies and complete *** of them were collected from the late Middle Jurassic Jiulongshan Formation of Daohugou in southeastern Inner Mongolia,*** with two known genera,Mesosciophilina(Kovalev,1985) and Mesosciophilopsis(Blagoderov,1994),the new genus has transitional characters. The distribution pattern of Mesosciophilidae is briefly discussed.

关键词： Mesosciophilidae Middle Jurassic Jiulongshan Formation

Efficient Distributed Estimation of High-dimensional Sparse Precision Matrix for Transelliptical Graphical Models

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Acta Mathematica Sinica,English Series 2021年第5期37卷 689-706页

作者： Guan Peng WANG Heng Jian CUI School of Mathematical Sciences Capital Normal UniversityBeijing 100048P.R.China

In this paper,distributed estimation of high-dimensional sparse precision matrix is proposed based on the debiased D-trace loss penalized lasso and the hard threshold method when samples are distributed into different machines for transelliptical graphical *** a certain level of sparseness,this method not only achieves the correct selection of non-zero elements of sparse precision matrix,but the error rate can be comparable to the estimator in a non-distributed *** numerical results further prove that the proposed distributed method is more effective than the usual average method.

关键词： Distributed estimator sparse precision matrix high-dimensional hard threshold efficient communication

α-Ketoglutarate dehydrogenase(KGDH):A new balancer between energy metabolism and gene expression in plants

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Journal of Integrative Plant Biology 2023年第8期65卷 1843-1845页

作者： Wenwen Zhu Yikun He College of Life Sciences Capital Normal UniversityBeijing 100048China

Sessile plants can adjust their growth and development in response to environmental ***(light),is the primary source of energy for all life on the earth,in the long course of phylogenetic evolution,plants have developed a unique relationship with light:they can absorb light energy and convert it into organic matter for use by themselves and others。

关键词： energy metabolism convert

Derlin-1 and TER94/VCP/p97 are required for intestinal homeostasis

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Journal of Genetics and Genomics 2022年第3期49卷 195-207页

作者： Fuli Liu Hang Zhao Ruiyan Kong Lin Shi Zhengran Li Rui Ma Huiqing Zhao Zhouhua Li College of Life Sciences Capital Normal UniversityBeijing 100048China Department of Neurology Xuanwu HospitalCapital Medical UniversityBeijing 100053China

Adult stem cells are critical for the maintenance of residential tissue homeostasis and functions. However,the roles of cellular protein homeostasis maintenance in stem cell proliferation and tissue homeostasis are not fully understood. Here, we find that Derlin-1 and TER94/VCP/p97, components of the endoplasmic reticulum(ER)-associated degradation(ERAD) pathway, restrain intestinal stem cell proliferation to maintain intestinal homeostasis in adult Drosophila. Depleting any of them results in increased stem cell proliferation and midgut homeostasis disruption. Derlin-1 is specifically localized in the ER of progenitors, and its Cterminus is required for its function. Interestingly, we find that increased stem cell proliferation is resulted from elevated ROS levels and activated JNK signaling in Derlin-1-or TER94-deficient progenitors. Further removal of reactive oxygen species(ROS) or inhibition of JNK signaling almost completely suppresses increased stem cell proliferation. Together, these data demonstrate that the ERAD pathway is critical for stem cell proliferation and tissue homeostasis. Thus, we provide insights into our understanding of the mechanisms underlying cellular protein homeostasis maintenance(ER protein quality control) in tissue homeostasis and tumor development.

关键词： Derlin-1 TER94/VCP/p97 ERAD Intestinal homeostasis Drosophila

New fossil elaterids(Insect:Coleoptera:Polyphaga:Elateridae) from the Middle Jurassic of Inner Mongolia,China

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Progress in Natural Science:Materials International 2009年第10期19卷 1433-1437页

作者： Huali Chang,Yunyun Zhao,Dong Ren College of Life Science,capital normal university,beijing 100048,China [a]College of Life Science Capital Normal University Beijing 100048 China

A new genus with a new species of fossil elaterid,Paraprotagrypnus superbus *** ***.,from the Middle Jurassic Jiulongshan Formation in Daohugou Village(N41°18.9790,E119°14.3180),Shantou Township,Ningcheng County,Inner Mongolia,China is described and *** genus Paraprotagrypnus belongs to the family of Elateridae,subfamily of Protagrypninae and tribe of *** primitive characters of the new genus and new species shed light on the ages between the Jiulongshan Formation in Inner Mongolia and the Yixian Formation in the western Liaoning Province of *** habitat of the new species is briefly discussed.

关键词： Elateridae New genus Paraprotagrypnus superbus sp.nov. Middle Jurassic Jiulongshan Formation China

Effect of fabrication errors on multiple second-harmonic generation considering pump depletion

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Chinese Optics Letters 2015年第13期13卷 1-4页

作者：赵秋爽赵丽明 Center for Theoretical Physics Department of Physics Capital Normal University Beijing 100048 China

We investigate second-harmonic generation （SHG） from aperiodic optical superlattices in the regime of pump depletion, where the influence of typical fabrication errors which can be introduced by the random fluctuation of the thickness for each domain in the simulation is considered according to the actual case. It is found that both the SHG conversion efficiencies calculated in undepleted pump approximation （UPA） and an exact solution decrease when the fluctuation gets larger. However, the decreasing degree is related to the wavelength of the fundamental wave （FW）, and the longer the FW wavelength, the lesser the corresponding conversion efficiency reduction. A relative tolerance with respect to SHG conversion efficiency calculated in UPA and exact solution is defined in a previous work, in which a typical model based on the relative tolerance curves is proposed to estimate the SHG conversion efficiency. The simulation results exhibit that the relative tolerance curves are basically coincident with the standard curve when the random fluctuation is very small （typically below 1%）. However, as the fluctuation increases, the relative tolerance curves exhibit a large deviation from the standard one, and the deviation is also determined by the wavelength of the FW.

关键词： Harmonic generation