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A Denoiser for Correlated Noise Channel Decoding: Gated-Neural Network

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china Communications 2024年第2期21卷 122-128页

作者： Xiao Li ling {1. Zhen dai Yonggang Lei School of Electronic and Information Engineering Beihang UniversityBeijing 100191China beijing Institute of Tracking and Telecommunications Technology BITTT

This letter proposes a sliced-gated-convolutional neural network with belief propagation(SGCNN-BP) architecture for decoding long codes under correlated noise. The basic idea of SGCNNBP is using Neural Networks(NN) to transform the correlated noise into white noise, setting up the optimal condition for a standard BP decoder that takes the output from the NN. A gate-controlled neuron is used to regulate information flow and an optional operation—slicing is adopted to reduce parameters and lower training complexity. Simulation results show that SGCNN-BP has much better performance(with the largest gap being 5dB improvement) than a single BP decoder and achieves a nearly 1.B improvement compared to Fully Convolutional Networks(FCN).

关键词： belief propagation channel decoding correlated noise neural network

Plutonium utilization in a small modular molten-salt reactor based on a batch fuel reprocessing scheme

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Nuclear science and Techniques 2024年第4期35卷 15-28页

作者： xue-Chao {1. Rui yan Gui-feng Zhu ya-Fen Liu Jian Guo Xiang-Zhou Cai yang Zou Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201800China CAS Innovative Academies in TMSR Energy System Chinese Academy of SciencesShanghai 201800China university of Chinese Academy of {1.s Beijing 100049China

A molten salt reactor(MSR)has outstanding features considering the application of thorium fuel,inherent safety,sustainability,and resistance to ***,fissile material^(233)U is significantly rare at the current stage,thus it is difficult for MSR to achieve a pure thorium-uranium fuel ***,using plutonium or enriched uranium as the initial fuel for MSR is more *** this study,we aim to verify the feasibility of a small modular MSR that utilizes plutonium as the starting fuel(SM-MSR-Pu),and highlight its advantages and ***,the structural design and fuel management scheme of the SM-MSR-Pu were ***,the neutronic characteristics,such as the graphite-irradiation lifetime,burn-up performance,and coefficient of temperature reactivity were calculated to analyze the physical characteristics of the *** results indicate that plutonium is a feasible and advantageous starting fuel for a SM-MSR;however,there are certain shortcomings that need to be *** a 250 MWth SM-MSR-Pu,approximately 288.64 kg^(233)U of plutonium with a purity of greater than 90% is produced while 978.00 kg is burned every ten *** temperature reactivity coefficient decreases from -4.0 to -6.5 pcm K^(-1. over the 50-year operating time,which ensures a long-term safe ***,the amount of plutonium and accumulation of minor actinides(MAs)would increase as the burn-up time increases,and the annual production and purity of^(233)U will *** achieve an optimal burn-up performance,setting the entire operation time to 30 years is ***,more than 3600 kg of plutonium eventually accumulate in the *** research is required to effectively utilize this accumulated plutonium.

关键词： Molten salt fuel Plutonium utilization ^(233)U TRUs mole fraction Temperature feedback coefficient

Protective Effects of Vitamin E against Oxidative Damage Induced by Aβ(1.40)Cu(Ⅱ)Complexes

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Acta Biochimica et Biophysica Sinica 2007年第2期39卷 123-130页

作者： xueling dai~1.yaxuan sun~2 and zhaofeng jiang~2 ~1College of life science,capital normal university,Bejing 1.0037,china ~2College of Applied sciences Humanities of beijing Union university,beijing 100083,china College of life {1. Capital Normal UniversityBeijing 100037 China College of Applied sciences and Humanities of {1. Union university{1. 1.0083 China

β-amyloid peptide （Aβ） is considered to be responsible for the formation of senile plaques,which is the hallmark of Alzheimer's disease （AD）.Oxidative stress,manifested by protein oxidation andlipid peroxidation,among other alterations,is a characteristic of AD brain.A growing body of evidence hasbeen presented in support of Aβ1.40forming an oligomeric complex that binds copper at a CuZn superoxidedismutase-like binding site. Aβ1.40Cu（Ⅱ） complexes generate neurotoxic hydrogen peroxide （H2O2） from O2via Cue+ reduction,though the precise reaction mechanism is *** toxicity of Aβ1.40or the Aβ1.40Cu（Ⅱ）complexes to cultured primary cortical neurons was partially attenuated when （+）-α-tocopherol （vitamin E）as free radical antioxidant was added at a concentration of 1.0 μ*** data derived from lactate dehydro-genase （LDH） release and the formation of H2O2confirmed the results from the MTT *** findingsindicate that copper binding to Aβ1.40can give rise to greater production of H2O2, which leads to a break-down in the integrity of the plasma membrane and subsequent neuronal *** treated with vitaminE exhibited much slighter damage,suggesting that vitamin E plays a key role in protecting neuronal cellsfrom dysfunction or death.

关键词： Aβ1.40Cu(II)complex vitamin E neuronal oxidative damage H2O2 generation lactate dehydrogenase(LDH)release

Theoretical study on thermal decomposition of azoisobutyronitrile in ground state

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science {1. Chemistry 2004年第5期47卷 373-380页

作者： sun Chengke1.2, {1. Hongmei1.& LI Zonghe1.1. Department of Chemistry, beijing normal university, beijing 1.0875, china 2. Department of Chemistry, Qujing normal College, Qujing 655000, china Dept. of Chem. Beijing Normal Univ. Beijing 100875 China Dept. of Chem. Qujing Normal Coll. Qujing 655000 China

The thermal decomposition mechanisms of azoisobutyronitrile (AIBN) in the ground state have been investigated systematically. Based on the potential energy surfaces (PES) of various possible dissociation paths obtained using the semiempirical AM1.method with partial optimization, the density function theory B3LYP/6-31.G* method was employed to optimize the geometric parameters of the reactants, the intermediates, the products and the transition states, which were further confirmed by the vibrational analysis. The obtained results show that the re- action process of the two-bond (three-body) simultaneous cleavage Me2(CN)C─ N=N─ C(CN)Me2? 2Me2(CN)C?+N2 is much more favorable than the reaction process of the two one- bond asynchronous cleavage Me2(CN)CN=N─C(CN)Me2 ? Me2(CN)CN=N?+ Me2(CN)C?? Me2(CN)C?+ N2. It was suggested that the electron shrinking effect of double bond (─N=N─) in AIBN and the stabilities of the Me2(CN)C?radical as well as N2 molecule are main factors of leading to the reaction proceeding in the former pathway. The calculation results were consistent with all the experimental facts.

关键词： azoisobutyronitrile, radicals, thermal decomposition, density function theory (DFT).

Calculating soil moisture by remote sensing and analyzing hydrologic cycle process in the Yellow River basin

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science {1.(Technological sciences) 2004年第Z1期47卷 1-13页

作者： yaNG Shengtian1.& LIU Changming1. 2 1. School of Environmental {1.s, beijing normal university, beijing 1.0875, china 2. Institute of Geographic {1. and Natural Resources Research, beijing 1.01.1. china School of Environmental sciences Beijing Normal University Beijing China Institute of Geographic science and Natural Resources Research Beijing China

Based on the AVHRR pathfinder remote sensing data, soil moisture, precipitation and evaporation during the period of 1.82—1.98, soil moisture of all layers of soil-profile (0—1.m) in the Yellow River basin over the 1. years are calculated by the remote sensing model of calculating soil water. The Yellow River basin is divided into seven subcatchments as control sections at the location of six hydrologic stations (Lanzhou, Toudaoguai, Longmen, Sanmenxia, Huayuankou and Lijin). After calculating soil moisture and obtaining runoff data and precipitation data, the dynamical features of hydrological cycle in the Yellow River basin are analyzed for the period from 1.82 to 1.88 using water balance method. The conclusions are as follows: It is feasible to calculate the soil water on the macro-scale, in the soil profile with temporal continuity by means of remote sensing and survey in land. Some values of the key water cycle factors in the Yellow River are obtained, which include the annual precipitation of 4000 km3, the evapotranspiration of 3000-3500 km3, and the soil moisture transformation of ?500- 500 km3. Consequently, we analyzed the process of the water cycle in the Yellow River over the 1. years, and the results show that the segment upstream of Lanzhou city is a relatively humid region, and the area of internal waters and the reaches of Shanshan is the most desiccated region. Therefore, the runoff in the depth process is intensive and the runoff-generating process is weak in more arid regions.

关键词： the Yellow River, soil moisture, remote sensing, hydrologic cycle.

The toxicity of Cu^(2+) to Microcystis aeruginosa using dielectric spectroscopy

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science {1. Chemistry 2010年第3期53卷 631-636页

作者： YU yanLi1.BAI Wei1.{1. KongShuang1. ZHOU YunLong2 1.ollege of Chemistry,beijing normal university,beijing 1.0875,china 2College of life science,beijing normal university,beijing 1.0875,china College of Chemistry Beijing Normal University Beijing China College of life {1. Beijing Normal University Beijing China

Dielectric spectroscopy(DS) was utilized to investigate the toxicity of the Cu2+ solution to Microcystis *** was found that 0.04 mM Cu2+ had no effect on dielectric increment,whereas the Cu2+ concentrations above 0.1.mM decreased the value of Δε/Δε *** toxic effect of Cu2+ on *** cells was time-dependent and *** was a threshold concentration between 0.04 mM and 0.1.mM,which affected the cell membrane,suggesting that Cu2+ at the concentrations higher than 0.1.mM caused serious plasmalemma damage to *** *** addition of 1.mM Ca2+ or Mg2+ did not protect *** cells from 1.mM Cu2+ *** study demonstrates that DS monitors cell biomass facilitating observation of the toxic effects of metal ions.

关键词： Microcystis aeruginosa dielectric spectroscopy dielectric increment cupric ion toxicity

Theoretical study on the reaction mechanism of (CH3)3CO(.) radical with NO

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science {1. Chemistry 2004年第4期47卷 289-294页

作者： zhao Hongmei1.2, LIU Kun1. {1. Chengke1.& LI Zonghe1.1. Department of Chemistry, beijing normal university, beijing 1.0875, china 2. Department of Chemistry, Beihua university, Jilin 1.201., china Department of Chemistry Beijing Normal University Beijing China Department of Chemistry Beihua University Jilin China

The reaction mechanism of (CH3)3CO? radical with NO is theoretically investigated at the B3LYP/6-31.* level. The results show that the reaction is multi-channel in the single state and triplet state. The potential energy surfaces of reaction paths in the single state are lower than that in the triple state. The balance reaction: (CH3)3CONO(CH3)3CO?+NO, whose potential energy surface is the lowest in all the reaction paths, makes the probability of measuring (CH3)3CO? radical increase. So NO may be considered as a stabilizing reagent for the (CH3)3CO? radical.

关键词： (CH3)3CO. radical DFT reaction mechanism NO

Molecular structure and biological function of proliferating cell nuclear antigen

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Progress in Natural science:Materials International 2007年第10期17卷 1127-1135页

作者： Song Nanmeng1. Sang Jianli1.and Xu Heng2(1. Institute of Cell Biology, College of life {1., beijing normal university, beijing 1.0875, china 2. Emory university School of Medicine, GA 30332, USA) Institute of Cell Biology College of Life Science Beijing Normal University Beijing 100875 China School of Medicine Emory University GA 30332 United States

Proliferating cell nuclear antigen (PCNA) is the core component of replication complex in eukaryote. As a processive factor of DNA polymerase delta, PCNA coordinates the replication process by interacting with various replication proteins. PCNA appears to play an essential role in many cell events, such as DNA damage repair, cell cycle regulation, and apoptosis, through the coordination or organization of different partners. PCNA is an essential factor in cell proliferation, and has clinical significance in tumor research. In this article we review the functional structure of PCNA, which acts as a function switch in different cell events.

关键词： PCNA Function Switch PCNA Binding Motif Cell Cycle DNA Replication DNA Repair.

Phylogeny of Ptychostomum (Bryaceae,Musci) inferred from sequences of nuclear ribosomal DNA internal transcribed spacer (ITS) and chloroplast rps4

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Journal of Systematics and Evolution 2009年第4期47卷 311-320页

作者： ~(1.2)Chen-Ying WANG ~1.ian-Cheng zhao~* 1.College of {1. science,Hebei normal university,Shijiazhuang 05001.,china) 2(Department of {1. science,Zhengzhou Teachers College,Zhengzhou 450044,china) (College of life {1. Hebei Normal University Shijiazhuang 050016 China) (Department of life {1. Zhengzhou Teachers College Zhengzhou 450044 China)

The phylogeny of Ptychostomum was first undertaken based on analysis of the internal transcribed spacer(ITS)region of the nuclear ribosomal(nr)DNA and by combining data from nrDNA ITS and chloroplast DNA rps4 *** parsimony,maximum likelihood,and Bayesian analyses all support the conclusion that the reinstated genus Ptychostomum is not *** funkii(Schw(a|¨)gr.)*** (≡Bryum funkii Schw(a|¨)gr.)is placed within a clade containing the type species of Bryum,*** Hedw. The remaining members of Ptychostomum investigated in the present study constitute another well-supported clade. The results are congruent with previous molecular *** the basis of phylogenetic evidence,we agree with transferring *** Mü***.(≡***(Brid.)Turton≡Bryum archangelicum Bruch & Schimp.), Bryum lonchocaulon Mü***.,Bryum pallescens *** Schw(a|¨)gr.,and Bryum pallens *** Ptychostomum.

关键词： Bryum molecular phylogeny nuclear ribosomal DNA internal transcribed spacer sequences Ptychostomum rps4 sequences.