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Endogenous adult neurogenesis and cognitive function recovery following traumatic brain injury in the rat hippocampus 被引量:2
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作者 Wangmiao Zhao Linchun Huan +6 位作者 Yan Zhao Jie Zhao Qi Zhang Lin Zhang Rong Yan shuyuan yang Xinyu yang 《Neural Regeneration Research》 SCIE CAS CSCD 2010年第9期645-650,共6页
BACKGROUND:Endogenous neural progenitor cells play a beneficial role for cognitive recovery following traumatic brain injury.However,there are few classification-control studies aimed at varying graded brain trauma.O... BACKGROUND:Endogenous neural progenitor cells play a beneficial role for cognitive recovery following traumatic brain injury.However,there are few classification-control studies aimed at varying graded brain trauma.OBJECTIVE:To observe the effects of adult endogenous neurogenesis on cognitive function repair and regeneration of neural progenitor cells following varying graded traumatic hippocampal injury to determine the significance of endogenous neurogenesis in the repair of brain injury.DESIGN,TIME AND SETTING:A randomized,controlled,animal experiment was performed at the Key Laboratory of Injuries,Variations and Regeneration of Nervous System,Tianjin Medical University General Hospital,from February to October 2009.MATERIALS:Mouse anti-rat 5-bromodeoxyuridine (BrdU) and neuronal nuclei (NeuN) monoclonal antibodies were purchased from Millipore Corporation,USA.METHODS:A total of 45 Wistar rats were randomly assigned to three groups.Mild and severe injury groups were respectively subjected to (182 ± 2) kPa and (284 ± 4) kPa lateral fluid percussion to establish models of brain injury,and the control group was subjected to surgery with no lateral fluid percussion.MAIN OUTCOME MEASURES:Cognitive function was estimated using the Morris water maze.Proliferation,survival,and differentiation of newly generated cells in the injured hippocampus were observed through the use of immunofluorescent staining.RESULTS:At 7 days post-injury,the number of BrdU+ cells in the hippocampal dentate gyrus significantly increased in the mild and severe injury groups compared with the control group (P〈0.01).At 61 days post-injury,the number of BrdU7NeuN+ cells in the hippocampal dentate gyrus was significantly greater in the mild injury group compared with the severe injury and control groups (P〈 0.01).In addition,the control group exhibited the greatest proportion of surviving cells that differentiated into mature neurons compared with the injury groups (P〈 0.01).Moreover,at 61 days post-injury,cognitive function in rats with mild injury recovered to normal levels,whereas the severe injury group exhibited cognitive deficits (P〈 0.01).CONCLUSION:Traumatic brain injury may be a stimulation factor for proliferation of neural progenitor cells in the adult hippocampus but severe brain trauma does not lead to an increased number of newly generated cells.Endogenous adult neurogenesis repairs neurological functions to an extent.However,recovery of neurological function remains limited following severe traumatic brain injury. 展开更多
关键词 traumatic brain injury HIPPOCAMPUS Morris water maze NEUROGENESIS cognitive function brain injury neural regeneration
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具有已知约化态的无限维量子系统态的秩
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作者 杨舒媛 贺衎 《数学物理学报(A辑)》 CSCD 北大核心 2022年第1期1-8,共8页
若H和K为两个无限维量子系统(即无限维复Hilbert空间).令ρ是H■K上的量子态,在已知其两个约化态tr_(H)(ρ)与tr_(K)(ρ)的情况下,该文确定ρ所有可能的秩.
关键词 量子态 约化态 偏迹
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通过应变工程提高有机半导体的迁移率
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作者 汪兆锋 武显硕 +7 位作者 杨书院 姚佳荣 沈贤锋 高丕超 姚惜梦 曾东 李荣金 胡文平 《Science China Materials》 SCIE EI CAS CSCD 2024年第2期665-671,共7页
有机半导体(OSCs)是推动柔性电子发展的关键.然而,其应用一直受到其较低迁移率的阻碍.虽然分子工程和器件工程可以提高OSC迁移率,但近年来进展几乎停滞不前.本研究揭示了有机半导体在应变下的层数依赖电荷输运特性,并通过应变工程可大... 有机半导体(OSCs)是推动柔性电子发展的关键.然而,其应用一直受到其较低迁移率的阻碍.虽然分子工程和器件工程可以提高OSC迁移率,但近年来进展几乎停滞不前.本研究揭示了有机半导体在应变下的层数依赖电荷输运特性,并通过应变工程可大幅提高其迁移率.施加应变可以减小分子间π-π间距并减少电子-声子散射,从而提高电荷输运效率.我们观察到应变因子和材料厚度之间存在直接相关性,较薄的晶体具有较高的应变因子.使用分子级薄的二维分子晶体,我们观察到迁移率显著提高了58%.我们的研究结果为提高有机半导体的迁移率开辟了新的途径. 展开更多
关键词 2D molecular crystal organic field-effect transistor MOBILITY strain engineering
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Assessing current and future soil erosion under changing land use based on InVEST and FLUS models in the Yihe River Basin,North China
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作者 Xinru Qiao Zijun Li +3 位作者 Jinkuo Lin Haijun Wang Shuwei Zheng shuyuan yang 《International Soil and Water Conservation Research》 SCIE CSCD 2024年第2期298-312,共15页
The Yihe River Basin is a key area for water conservation and soil erosion control in northern China.The excessive development of land resources is a major factor causing soil erosion and ecological degradation.Howeve... The Yihe River Basin is a key area for water conservation and soil erosion control in northern China.The excessive development of land resources is a major factor causing soil erosion and ecological degradation.However,the impacts of land use change on soil erosion in the basin are not yet clearly.Understanding the complex relationship between land use and soil erosion is an important way to promote the development of land resources utilization and ecological construction from cognition to decision-making.This study simulated the temporal-spatial changes of soil erosion in the basin from 1956 to 2020 using Integrated Valuation of Ecosystem Services and Tradeoffs(InVEST)model,and evaluated the changes of soil erosion under different land use scenarios from 2020 to 2050 using Future Land Use Simulation(FLUS)model.From 1956 to 2020,the overall soil erosion intensity showed a slight decreasing trend,and the average annual soil erosion modulus was 38.21 t/ha/year.Soil erosion intensity was higher in the central and northern mountainous areas,while it was lower in the flat alluvial plains in the south.Arable land(4.07 t/ha/year)was the largest contributor to the amount of soil erosion,and land use changes caused the soil erosion intensity to fluctuate and decrease after 1995.From 2020 to 2050,soil erosion varied widely under different land use scenarios,and the land use pattern targeting ecological priority development would effectively mitigate soil erosion.Therefore,optimizing land use patterns and structures are critical initiatives to prevent soil erosion. 展开更多
关键词 Soil erosion Land use change InVEST model FLUS model Yihe River Basin
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基于散射图卷积网络的PolSAR影像地物分类 被引量:1
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作者 刘旭 李玲玲 +3 位作者 刘芳 杨淑媛 侯彪 焦李成 《中国科学:信息科学》 CSCD 北大核心 2022年第10期1900-1914,共15页
本文针对极化合成孔径雷达(polarimetric synthetic aperture radar,PolSAR)图像解译中特征提取不足与目标分类困难的问题,进行了深入的研究,提出了一种基于散射图卷积网络的PolSAR影像分类方法.在特征提取方面,本文给出了极化散射编码... 本文针对极化合成孔径雷达(polarimetric synthetic aperture radar,PolSAR)图像解译中特征提取不足与目标分类困难的问题,进行了深入的研究,提出了一种基于散射图卷积网络的PolSAR影像分类方法.在特征提取方面,本文给出了极化散射编码的一维表现形式;同时,考虑目标散射的特性和像素间的复杂关系,结合图论理论,提出了一种新的散射机制的图表示模型,来刻画复杂的极化散射机理;最后,将这种新的散射建模方法和图卷积网络结合,提出了PolSAR图像分类的新方法,从而更加高效、高精度地完成分类任务.实验结果表明,在5幅公开的PolSAR图像上(PolSF数据集),本文提出的算法具有良好的分类性能. 展开更多
关键词 散射 特征表示 图卷积网络 极化SAR图像 地物分类
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Highly efficient modulation of the electronic properties of organic semiconductors by surface doping with 2D molecular crystals 被引量:1
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作者 Yu Zhang shuyuan yang +6 位作者 Xiaoting Zhu Fei Zhai Yiyu Feng Wei Feng Xiaotao Zhang Rongjin Li Wenping Hu 《Science China Chemistry》 SCIE EI CAS CSCD 2020年第7期973-979,共7页
Doping is a critically important strategy to modulate the properties of organic semiconductors(OSCs) to improve their optoelectrical performances. Conventional bulk doping involves the incorporation of foreign molecul... Doping is a critically important strategy to modulate the properties of organic semiconductors(OSCs) to improve their optoelectrical performances. Conventional bulk doping involves the incorporation of foreign molecular species(i.e., dopants) into the lattice of the host OSCs, and thus disrupts the packing of the host OSCs and induces structural defects, which tends to reduce the mobility and(or) the on/off ratio in organic field-effect transistors(OFETs). In this article, we report a highly efficient and highly controllable surface doping strategy utilizing 2D molecular crystals(2DMCs) as dopants to boost the mobility and to modulate the threshold voltage of OFETs. The amount of dopants, i.e., the thickness of the 2DMCs, is controlled at monolayer precision, enabling fine tuning of the electrical properties of the OSCs at unprecedented accuracy. As a result, a prominent increase of the average mobility from 1.31 to 4.71 cm2 V-1 s-1 and a substantial reduction of the threshold voltage from -18.5 to -1.8 V are observed. Meanwhile, high on/off ratios of up to 108 are retained. 展开更多
关键词 organic field-effect transistor organic single crystal 2D molecular crystal surface doping charge transport
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Risks posed by obesity to body-surface narrowband wireless communication
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作者 Xiaodong yang Qing Zhang +4 位作者 shuyuan yang Aifeng Ren Zhiya Zhang Karen M.von Deneen yang Hao 《Chinese Science Bulletin》 SCIE EI CAS 2014年第29期3949-3954,共6页
Little work has been done on the effect of being overweight on the wireless narrowband radio propagation of wearable medical instruments.In this paper,by applying a finite-difference time-domain technique and a statis... Little work has been done on the effect of being overweight on the wireless narrowband radio propagation of wearable medical instruments.In this paper,by applying a finite-difference time-domain technique and a statistical learning method,the authors find that being overweight might be an obstacle to body-surface wireless communication.The findings have certain instructive meanings for those engineers who are designing on-body medical instruments for patients,especially those patients who are overweight. 展开更多
关键词 无线通信 体表面 窄带 风险 肥胖 统计学习方法 医疗器械 无线电传播
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Spin injection and transport in single-crystalline organic spin valves based on TIPS-pentacene
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作者 Ying Wang Jiarong Yao +10 位作者 Shuaishuai Ding Siyu Guo Dapeng Cui Xinyue Wang shuyuan yang Lijuan Zhang Xinzi Tian Di Wu Chao Jin Rongjin Li Wenping Hu 《Science China Materials》 SCIE EI CAS CSCD 2021年第11期2795-2804,共10页
Single crystals of organic semiconductors with perfect crystal structure and minimal density of defects can exhibit high mobility and low spin scattering compared with their amorphous or polycrystalline counterparts.T... Single crystals of organic semiconductors with perfect crystal structure and minimal density of defects can exhibit high mobility and low spin scattering compared with their amorphous or polycrystalline counterparts.Therefore,these materials are promising candidates as the spin transport media to obtain long spin relaxation times and spin diffusion lengths in spintronic devices.However,the investigation of spin injection and transport properties in organic single crystals is hindered by the inability to construct devices such as single-crystalline organic spin valves(OSVs).Herein,thin and large organic single crystals of 6,13-bis(triisopropylsilylethynyl)pentacene(TIPS-pentacene)were grown on a liquid substrate and transferred to a target substrate carrying ferromagnetic electrodes to construct single-crystalline OSVs.The magnetoresistance(MR)responses of the single crystals were investigated to study their spin injection and transport properties.MR value as high as 17%was probed with an intermediate layer thickness of 269 nm.More importantly,spin transport was still observed in a single crystal of a thickness up to 457 nm,which was much larger than that of polycrystalline thin film.Our research provides a general methodology for constructing single-crystalline OSVs and paves the way to probe the intrinsic spin transport properties of organic semiconductors based on single crystals. 展开更多
关键词 organic single crystal organic semiconductor MAGNETORESISTANCE organic spin valve SPINTRONICS
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A new directional multi-resolution ridgelet network
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作者 shuyuan yang Licheng JIAO Min WANG 《Frontiers of Electrical and Electronic Engineering in China》 CSCD 2008年第2期198-203,共6页
In this paper,we propose a new directional multi-resolution ridgelet network(DMRN)based on the ridgelet frame theory,which uses the ridgelet as the activation function in a hidden layer.For the multi-resolution proper... In this paper,we propose a new directional multi-resolution ridgelet network(DMRN)based on the ridgelet frame theory,which uses the ridgelet as the activation function in a hidden layer.For the multi-resolution properties of the ridgelet function in the direction besides scale and position,DMRN has great capabilities in catching essential features of direction-rich data.It proves to be able to approximate any multivariate function in a more stable and efficient way,and optimal in approximating functions with spatial inhomogeneities.Besides,using binary ridgelet frame as the mathematical foundation in its construction,DMRN is more flexible with a simple structure.The construction and the learning algorithm of DMRN are given.Its approximation capacity and approximation rate are also analyzed in detail.Possibilities of applications to regression and recognition are included to demonstrate its superiority to other methods and feasibility in practice.Both theory analysis and simulation results prove its high efficiency. 展开更多
关键词 ridgelet frame directional multi-resolution ridgelet network
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