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Enriched environment upregulates growth-associated protein 43 expression in the hippocampus and enhances cognitive abilities in prenatally stressed rat offspring

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Neural Regeneration Research 2012年第25期7卷 1967-1973页

作者： zhengyu zhang Hua zhang Baoling Du Zhiqiang Chen Department ofHistologyand Embryology Guangzhou Medical University Guangzhou 510185 Guangdong Province China Department of Stomatology First Affiliated Hospital Jinan University Guangzhou 510630 Guangdong Province China Department of Orthopedics Surgery Liaocheng People's Hospital Liaocheng 252000 Shandong Province China

In our previous study, we reported that prenatal restraint stress could induce cognitive deficits, which correlated with a change in expression of growth-associated protein 43 in the hippocampus. In this study, we investigated the effects of enriched environment on cognitive abilities in prenatally stressed rat offspring, as well as the underlying mechanisms. Reverse transcription-PCR and western blot assay results revealed that growth-associated protein 43 mRNA and protein levels were upregulated on postnatal day 15 in the prenatal restraint stress group. Growth-associated protein 43 expression was significantly lower in the prenatal restraint stress group compared with the negative control and prenatal restraint stress plus enriched environment groups on postnatal days 30 and 50. Morris water maze test demonstrated that cognitive abilities were noticeably increased in rats from the prenatal restraint stress plus enriched environment group on postnatal day 50. These results indicate that enriched environment can improve the spatial learning and memory ability of prenatally stressed offspring by upregulating growth-associated protein 43 expression.

关键词： prenatal restraint stress growth-associated protein 43 hippocampus Morris water maze enrichedenvironment cognition neural regeneration

Understanding land for high-quality development

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Journal of Geographical Sciences 2023年第2期33卷 217-221页

作者： JIN Gui PENG Jian zhang Lixiao zhang zhengyu School of Economics and Management China University of GeosciencesWuhan 430074China College of Urban and Environmental Sciences Peking UniversityBeijing 100871China School of Environment Beijing Normal UniversityBeijing 100875China School of Public Administration China University of GeosciencesWuhan 430074China

Land is the basis for human survival and production,providing food,fuel,fiber,and other ecosystem services(Verburg et al.,2013;Jin et al.,2021).Land-use change is both a cause and consequence of many biophysical and socioeconomic changes(Van and Verburg,2013).Human land-use activities have a great impact on biodiversity and the ecological environment by changing the ecosystem(Newbold et al.,2015;Asamoah et al.,2017;Tilman,2017;Zheng et al.,2020).Research by Song et al.(2018)showed that 60%of all land change is related to direct human activities and 40%to indirect drivers such as climate *** research is needed to deepen the understanding of the land system mechanism and the ecological impact of land *** such as land-use dynamic changes,interactions between humans and the natural environment in the land-use process,and the sustainability of land use have aroused widespread concern in the international academic community(Verburg et al.,2015;Liu,2018;Jin et al.,2019;Peng et al.,2020).

关键词： services ecosystem ecological

Solid-state reaction induced defects in multi-walled carbon nanotubes for improving microwave absorption properties

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Journal of Materials Science & Technology 2022年第13期108卷 37-45页

作者： Tong Gao zhengyu zhang Yixing Li Yujuan Song Huawei Rong Xuefeng zhang Key Laboratory for Anisotropy and Texture of Materials(MOE) School of Materials Science and EngineeringNortheastern UniversityShenyang 110819China Institute of Advanced Magnetic Materials College of Materials and Environmental EngineeringHangzhou Dianzi UniversityHangzhou 310012China

Dielectric polarization performance induced by defect engineering approach has been proved to be an effective way for improving the microwave absorption property of carbon-based *** by the solid-state reaction,the structural integrity of multi-walled carbon nanotubes(MWCNTs)would be broken along with the volume expansion and etching process of cobalt ***,the defects could be obtained and result in the enhancement of microwave absorption *** to the broken wall structures,the defect-distances(L_(D))and concentrations(n_(D))have been optimized to be 9.80 nm and3.37×10^(11) cm^(-2).The minimum reflection loss(RL)had reached-54.6 dB at 4.5 GHz with a thickness of4.13 mm and the corresponding effective absorption bandwidth(EAB_(<-10 dB))was analyzed to be 14.6 *** enhancement is correlated to the dielectric polarization and the permeability-to-permittivity transformation raised from the defect structures and *** present work demonstrates an effective strategy for tailoring the microwave absorption property of MWCNTs by engineering defect concentrations,and could be further extended to other carbon-based absorbents.

关键词： MWCNTs Defect engineering Microwave absorption Solid-state reaction Impedance matching

Application of Maximum Entropy Theorem in Channel Estimation

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Chinese Journal of Electronics 2020年第2期29卷 361-370页

作者： zhang zhengyu LOU Jinming JIN Mengdi YAO Yuan ZHU Jingguo Beijing University of Posts and Telecommunications Institute of Microelectronics Chinese Academy of Sciences

Scholars have been highly concerned with the blind channel estimation of multi-carrier modulation transmission systems, and the decoding process of block codes is usually closely related to channel ***, the accurate estimation of channel parameters is an important method to ensure communication accuracy. According to the transmission characteristics of multi-carrier modulated transmission channels, this paper uses the maximum likelihood theorem and the maximum entropy theorem to put forward a blind channel estimation method based on the proposed received signals. In order to verify the effect of this method, this research utilizes the BP decoding algorithm, which is used in LDPC coding, to calculate the symbol error rate and analyze the estimated effect of the transmission system. The simulation results show that the proposed method can estimate channel parameters effectively, and that the symbol error rate of LDPC decoding is almost similar to that of non-blind channel estimation. This implies that the proposed channel estimation method can effectively improve both channel utilization and transmission efficiency.

关键词： Multi-carrier modulation transmission Blind channel estimation Maximum entropy theorem Maximum likelihood theorem

Optimization of the Deployment of Temperature Nodes Based on Linear Programing in the Internet of Things

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Tsinghua Science and Technology 2013年第3期18卷 250-258页

作者： Liang Hu zhengyu zhang Feng Wang Kuo Zhao the School of Computer Science and Technology Jilin University

The Internet of Things emphasizes the concept of objects connected with each other, which includes all kinds of wireless sensor networks. An important issue is to reduce the energy consumption in the sensor networks since sensor nodes always have energy constraints. Deployment of thousands of wireless sensors in an appropriate pattern will simultaneously satisfy the application requirements and reduce the sensor network energy consumption. This article deployed a number of sensor nodes to record temperature data. The data was then used to predict the temperatures of some of the sensor node using linear programming. The predictions were able to reduce the node sampling rate and to optimize the node deployment to reduce the sensor energy consumption. This method can compensate for the temporarily disabled nodes. The main objective is to design the objective function and determine the constraint condition for the linear programming. The result based on real experiments shows that this method successfully predicts the values of unknown sensor nodes and optimizes the node deployment. The sensor network energy consumption is also reduced by the optimized node deployment.

关键词： Internet of Things linear programming optimized node deployment energy consumption

A Disintegrin and Metalloprotease 10 in neuronal maturation and gliogenesis during cortex development

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Neural Regeneration Research 2013年第1期8卷 24-30页

作者： Zhixing Ma Qingyu Li zhengyu zhang Yufang Zheng School of Life Sciences Fudan University

The multiple-layer structure of the cerebral cortex is important for its functions. Such a structure is generated based on the proliferation and differentiation of neural stem/progenitor cells. Notch functions as a molecular switch for neural stem/progenitor cell fate during cortex development but the mechanism remains unclear. Biochemical and cellular studies showed that Notch receptor activation induces several proteases to release the Notch intracellular domain （NICD）. A Disintegrin and Metalloprotease 10 （ADAM10） might be a physiological rate-limiting $2 enzyme for Notch activation. Nestin-driven conditional ADAM10 knockout in mouse cortex showed that ADAM10 is cdtical for maintenance of the neural stem cell population during early embryonic cortex development. However, the expression pattern and function of ADAM10 during later cerebral cortex development remains poorly understood. We performed in situ hybridization for ADAMIO mRNA and immunofluorescent analysis to determine the expression of ADAM10 and NICD in mouse cortex from embryonic day 9 （E14.5） to postnatal day 1 （P1）. ADAM10 and NICD were highly co-localized in the cortex of E16.5 to P1 mice. Comparisons of expression patterns of ADAM10 with Nestin （neural stem cell marker）, Tujl （mature neuron marker）, and S100β （gila marker） showed that ADAM10 expression highly matched that of S10013 and partially matched that of Tujl at later embryonic to early postnatal cortex developmental stages. Such expression patterns indicated that ADAM10-Notch signaling might have a critical function in neuronal maturation and gliogenesis during cortex development.

关键词： neural regeneration neurogenesis ADAM10 A Disintegrin and Metalloprotease Notch Notchintracellular domain TujlS100 Nestin cerebral cortex development neuronal maturation glialcell grants-supported paper photographs-containing paper neuroregeneration

Relation between standard entropies of elements and electronic configurations

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Chinese Science Bulletin 1999年第3期44卷 270-273页

作者： Desheng Ai Rongshu Zeng zhengyu zhang Chinese Acad Sci Inst Geol Beijing 100029 Peoples R China

A close relationship has been found between the standard entropies of elements and their electronic configurations. Based on the positions of elements in the periodic table and the variation in the standard entropies of elements, the standard entropies of elements can be expressed as the sum of two functions: S0= f（N） + f（E）, where S0 is the standard entropy of an element, N the principal quantum number, and E the number of outermost electrons. And the specific formula is S0=99.05N1/3 + [0.32（sp - 4）4 - 119.76] + [- 56.56N1/3 + 0.70（sd - 7）2 - 42.12]+[- 11.95 ×10-4（df- 8）4-105.70], where sp, sd, df are the numbers of the outermost electrons in the sp, sd, df regions of the periodic table, respectively. This formula helps reveal the essence of the standard entropies of elements and deepens our understanding of the thermodynamic characteristics of compounds.

关键词： standard entropy electronic configuration symmetry.

Transmission electron microscopy of synaptic ultrastructural white matter damage in neonatal rats

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Neural Regeneration Research 2010年第5期5卷 368-371页

作者： Baoli Yuan Sujuan Deng zhengyu zhang Ruilin Li Department of Pediatrics Second Affiliated Hospital of Guangzhou Medical College Guangzhou 510260 Guangdong Province China Department of Histology and Embryology Guangzhou Medical College Guangzhou 510182 Guangdong Province China Department of Pediatrics Second Hospital of Xi'an Jiaotong University Xi'an 710004 Shaanxi Province China

BACKGROUND： To date, animal models of white matter damage remain controversial. Mild grey matter damage should be the basis for animal models to investigate white matter disease. OBJECTIVE： To establish white matter damage in neonatal rats and evaluate feasibility of the established model by observing myelination and synaptic ultrastructure. DESIGN, TIME AND SETTING： A randomized, controlled, animal experiment was performed at the Laboratory of Histology and Embryology of Guangzhou Medical College from December 2008 to May 2009. MATERIALS： H600 transmission electron microscopy was provided by Hitachi, Japan. METHODS： A total of 39 neonatal, Sprague Dawley rats were randomly assigned to normal control （n = 12）, sham-surgery （n = 12）, and white matter damage （n = 15） groups. White matter damage rats were subjected to right common carotid artery ligation, followed by inhalation of nitrogen oxygen gas mixture （6% oxygen） for 4 hours. MAIN OUTCOME MEASURES： Myelin sheath and synaptic ultrastructure in the injured （right） hippocampal CA1 region in 1-month-old rats were observed through the use of transmission electron microscopy, and pathological changes in the cerebral cortex and corpus callosum of the right hemisphere were detected by hematoxylin-eosin staining. RESULTS： Obvious tissue loss was observed in the corpus callosum of the injured （right） hemisphere. Injured oligodendrocytes and disrupted myelination were observed in the white matter damage group. However, synaptic length in the active zones, width of synaptic cleft, thickness of postsynaptic density, and curvature of the synaptic interface remained unchanged following injury, compared with the control and sham-surgery groups （P 〉 0.05）. CONCLUSION： The established white matter damage model resulted in changes in myelination and slightly altered synaptic ultrastructures. The model could function as an ideal model for white matter damage in neonatal rats.

关键词： white matter damage myelin sheath synapse periventricular leukomalacia neural regeneration

List-Serial Pipelined Hardware Architecture for SCL Decoding of Polar Codes

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China Communications 2023年第3期20卷 175-184页

作者： Zhongxiu Feng Cong Niu zhengyu zhang Jiaxi Zhou Daiming Qu Tao Jiang Research Center of 6G Mobile Communications School of Cyber Science and Engineeringand Wuhan National Laboratory for OptoelectronicsHuazhong University of Science and TechnologyWuhan 430074China Institute of Space Integrated Ground Network Hefei 230094China The 38th Research Institute of China Electronics Technology Group Corporation Hefei 230088China School of Electronics Information and Communications Huazhong University of Science and TechnologyWuhan 430074China

For polar codes,the performance of successive cancellation list(SCL)decoding is capable of approaching that of maximum likelihood ***,the existing hardware architectures for the SCL decoding suffer from high hardware complexity due to calculating L decoding paths simultaneously,which are unfriendly to the devices with limited logical resources,such as field programmable gate arrays(FPGAs).In this paper,we propose a list-serial pipelined hardware architecture with low complexity for the SCL decoding,where the serial calculation and the pipelined operation are elegantly combined to strike a balance between the complexity and the ***,we employ only one successive cancellation(SC)decoder core without L×L crossbars,and reduce the number of inputs of the metric sorter from 2L to L+***,the FPGA implementations show that the hardware resource consumption is significantly reduced with negligible decoding performance loss.

关键词： successive cancellation list decoding po-lar codes hardware implementation pipelined archi-tecture