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Using GIS Spatial Distribution to Predict Soil Organic Carbon in Subtropical China

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Pedosphere 2004年第4期14卷 425-431页

作者： CHENGXian-Fu SHIXue-zheng YUDong-sheng panXian-Zhang WANGHong-Jie SUNWei-Xia StateKeyLaboratoryofSoilandSustainableAgriculture InstituteofSoilScienceChineseAcademyofSciencesNanjing210008（China）. Departmentofgeography AnhuiNormalUniversityWuhu241000（China）

Spatial distribution of organic carbon in soils is difficult to estimatebecause of inherent spatial variability and insufficient data. A soil-landscape model for a region,based on 151 samples for parent material and topographic factors, was established using a GISspatial analysis technique and a digital elevation model (DEM) to reveal spatial distributioncharacteristics of soil organic carbon (SOC). Correlations between organic carbon and topographicfactors were analyzed and a regression model was established to predict SOC content. Results forsurface soils (0-20 cm) showed that the average SOC content was 12.8 g kg^(-1), with the SOC contentbetween 6 and 12 g kg^(-1) occupying the largest area and SOC over 24 g kg^(-1) the smallest. Also,soils derived from phyllite were the highest in the SOC content and area, while soils developed onpurple shale the lowest. Although parent material, elevation, and slope exposure were allsignificant topographic variables (P < 0.01), slope exposure had the highest correlation to SOCcontent (r = 0.66). Using a multiple regression model (R^2 = 0.611) and DEM (with a 30 m X 30 mgrid), spatial distribution of SOC could be forecasted.

关键词： digital elevation model parent material regression model soil organiccarbon topography

The role of axon guidance molecules in the pathogenesis of epilepsy

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Neural Regeneration Research 2025年第5期20卷 1244-1257页

作者： zheng Liu Chunhua pan Hao Huang Department of Neurology Affiliated Hospital of Zunyi Medical UniversityZunyiGuizhou ProvinceChina

Current treatments for epilepsy can only manage the symptoms of the condition but cannot alter the initial onset or halt the progression of the disease. Consequently, it is crucial to identify drugs that can target novel cellular and molecular mechanisms and mechanisms of action. Increasing evidence suggests that axon guidance molecules play a role in the structural and functional modifications of neural networks and that the dysregulation of these molecules is associated with epilepsy susceptibility. In this review, we discuss the essential role of axon guidance molecules in neuronal activity in patients with epilepsy as well as the impact of these molecules on synaptic plasticity and brain tissue remodeling. Furthermore, we examine the relationship between axon guidance molecules and neuroinflammation, as well as the structural changes in specific brain regions that contribute to the development of epilepsy. Ample evidence indicates that axon guidance molecules, including semaphorins and ephrins, play a fundamental role in guiding axon growth and the establishment of synaptic connections. Deviations in their expression or function can disrupt neuronal connections, ultimately leading to epileptic seizures. The remodeling of neural networks is a significant characteristic of epilepsy, with axon guidance molecules playing a role in the dynamic reorganization of neural circuits. This, in turn, affects synapse formation and elimination. Dysregulation of these molecules can upset the delicate balance between excitation and inhibition within a neural network, thereby increasing the risk of overexcitation and the development of epilepsy. Inflammatory signals can regulate the expression and function of axon guidance molecules, thus influencing axonal growth, axon orientation, and synaptic plasticity. The dysregulation of neuroinflammation can intensify neuronal dysfunction and contribute to the occurrence of epilepsy. This review delves into the mechanisms associated with

关键词： axon guidance drug-resistant epilepsy epilepsy nerve regeneration nervous system diseases neural pathways neuroinflammatory diseases neuronal plasticity neurons synaptic remodeling

Passive activity enhances residual control ability in patients with complete spinal cord injury

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Neural Regeneration Research 2025年第8期20卷 2337-2347页

作者： Yanqing Xiao Mingming Gao Zejia He Jia zheng Hongming Bai Jia-sheng Rao Guiyun Song Wei Song Xiaoguang Li Beijing Key Laboratory for Biomaterials and Neural Regeneration Beijing Advanced Innovation Center for Biomedical EngineeringSchool of Biological Science and Medical EngineeringBeihang UniversityBeijingChina Department of Rehabilitation Evaluation China Rehabilitation Research CenterBeijingChina Cardiac Center Beijing Children’s HospitalCapital Medical UniversityBeijingChina The State Key Laboratory of Virtual Reality Technology and Systems Beihang UniversityBeijingChina Department of Rehabilitation Engineering China Rehabilitation Science InstituteBeijingChina

Patients with complete spinal cord injury retain the potential for volitional muscle activity in muscles located below the spinal injury ***,because of prolonged inactivity,initial attempts to activate these muscles may not effectively engage any of the remaining neurons in the descending pathway.A previous study unexpectedly found that a brief clinical round of passive activity significantly increased volitional muscle activation,as measured by surface *** this study,we further explored the effect of passive activity on surface electromyographic signals during volitional control tasks among individuals with complete spinal cord *** patients with chronic complete thoracic spinal cord injury were *** electromyography data from eight major leg muscles were acquired and compared before and after the passive activity *** results indicated that the passive activity led to an increased number of activated volitional muscles and an increased frequency of *** the cumulative root mean square of surface electromyography amplitude for volitional control of movement showed a slight increase after passive activity,the difference was not statistically *** findings suggest that brief passive activity may enhance the ability to initiate volitional muscle activity during surface electromyography tasks and underscore the potential of passive activity for improving residual motor control among patients with motor complete spinal cord injury.

关键词： complete spinal cord injury cycle training epidural electrical stimulation motor training passive activity physiological state spinal cord circuit surface electromyography volitional control task

Gut-brain axis as a bridge in obesity and depression:Mechanistic exploration and therapeutic prospects

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World Journal of Psychiatry 2025年第1期15卷 12-20页

作者： Rui-Ying Fang Xiao-Rui pan Xin-Xing Zeng zheng-zheng Li Bo-Fan Chen Hai-Min Zeng Jie Peng The Second Clinical Medical College The Second Affiliated HospitalJiangxi Medical CollegeNanchang UniversityNanchang 330006Jiangxi ProvinceChina

A recent study by Wang et al,published in the World Journal of Psychiatry,provided preventative and therapeutic strategies for the comorbidity of obesity and *** gut-brain axis,which acts as a two-way communication system between the gastrointestinal tract and the central nervous system,plays a pivotal role in the pathogenesis of these *** suggests that metabolic byproducts,such as short-chain fatty acids,lipopolysaccharide and bile acids,which are generated by the gut microbiota,along with neurotransmitters and inflammatory mediators within the gut-brain axis,modulate the host's metabolic processes,neuronal regulation,and immune responses through diverse *** interaction between obesity and depression via the gut-brain axis involves disruptions in the gut microbiota balance,inflammatory immune responses,and alterations in the neuroendocrine *** the gut-brain axis,for example,through a ketogenic diet,the use of probiotics,and the supplementation of antioxidants,offers new remedial approaches for obesity and *** research that explores the mechanisms of the gut-brain axis is needed to provide more evidence for clinical treatment.

关键词： Gut-brain axis Obesity Depression Gut microbiota Mechanism

丘陵山区林地土壤养分状况研究——以江西省兴国县为例

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水土保持学报 2003年第2期17卷 28-30页

作者：程先富史学正于东升潘贤章中国科学院南京土壤研究所江苏南京210008

在江西省兴国县林地采集84个耕层样品,样地按坡向、海拔、土壤类型和林分类型分类,用来比较和确定对林地土壤肥力的影响。分析结果表明:该区林地土壤pH、全N、有机质、全P和速效P的含量均较低,坡向朝南的低海拔土壤比坡向朝北的高海拔... 详细信息

在江西省兴国县林地采集84个耕层样品,样地按坡向、海拔、土壤类型和林分类型分类,用来比较和确定对林地土壤肥力的影响。分析结果表明:该区林地土壤pH、全N、有机质、全P和速效P的含量均较低,坡向朝南的低海拔土壤比坡向朝北的高海拔土壤的全N和有机质含量低;全N、有机质、全P含量在马尾松纯林中最低,全K含量却最高;全N和有机质含量在阔叶林中最高;全N和有机质含量由黄壤、黄红壤、棕红壤到红壤依次降低;坡向和全N、有机质含量呈显著正相关关系,海拔和全N、有机质含量呈极显著正相关关系;海拔和全P的相关关系达显著水平,呈显著正相关关系。

关键词：丘陵山区林地土壤养分状况兴国县土壤肥力地形土壤类型林分类型

RESREARCH ON FLUID CHARACTERISTIC WITHIN THE ROTATING-WING HEAT METER

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Journal of Hydrodynamics 2006年第4期18卷 458-463页

作者： LIU zheng-gang DU Guang-sheng WANG Ning pan Ji-hong School of Energy Source and Power Engineering Shandong University Jinan 250061 China

In order to improve the performance of rotating-wing heat meter and reduce the cost of development, the three dimensions numerical calculations of the intemal fluid characteristic within a heat meter are carried out based on the standard k-e turbulent mode, the finite volume method and SIMPLE algorithm. The speed field and pressure distribution within heat meter are analyzed according to the result of numerical calculation. The flux measurement accuracy and pressure loss of basal meter are forecasted according to the calculated results. The calculated results of the impeller＇s rotating speed are compared with experimental results and prove the validity of the calculated results. This researches shows the calculated results can forecast the performance parameters of basal meter and can provide great help for design of the heat meter.

关键词： heat meter numerical calculation rotating-wing

Gallium-Catalyzed Silicon Oxide Nanowire Growth

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Tsinghua Science and Technology 2005年第6期10卷 718-728页

作者： zheng Wei pan sheng Dai Douglas H. Lowndes Department of Materials Science and Engineering University of Tennessee Knoxville Tennessee 37996 USA Condensed Matter Sciences Division Oak Ridge National Laboratory Oak Ridge Tennessee 37830 USA Chemical Sciences Division Oak Ridge National Laboratory Oak Ridge Tennessee 37830 USA

Silicon oxide nanowires tend to assemble into various complex morphologies through a metalcatalyzed vapor-liquid-solid （VLS） growth process. This article summarizes our recent efforts in the controlled growth of silicon oxide nanowire assemblies by using molten gallium as the catalyst and silicon wafer, SiO powder, or silane （Sill4） as the silicon sources. Silicon oxide nanowire assemblies with morphologies of carrotlike, cometlike, gourdlike, spindlelike, badmintonlike, sandwichlike, etc. were obtained. Although the morphologies of the nanowire assemblies are temperatureand silicon source-dependent, they share similar structural and compositional features： all the assemblies contain a microscale spherical liquid Ga ball and a highly aligned, closely packed amorphous silicon oxide nanowire bunch. The Ga-catalyzed silicon oxide nanowire growth reveals several interesting new nanowire growth phenomena that expand our knowledge of the conventional VLS nanowire growth mechanism.

关键词： gallium silicon oxide nanowires vapor-liquid-solid (VLS) catalyst GaN powder Si wafer SiH4 gas SiO powder

Effect of Mn Modification on the Corrosion Susceptibility of Mg–Mn Alloys by Magnesium Scrap

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Acta Metallurgica Sinica(English Letters) 2021年第1期34卷 1-11页

作者： Dong-Dong Gu Jian Peng Jia-Wen Wang zheng-Tao Liu Fu-sheng pan State Key Laboratory of Mechanical Transmission College of Materials Science and EngineeringChongqing UniversityChongqing 400044China Chongqing Research Center for Advanced Materials Chongqing Academy of Science and TechnologyChongqing 401123China

The microstructure and anti-corrosion behavior of Mg–Mn alloys by magnesium scrap have been investigated in this *** results show that the size of the Fe-rich particles in magnesium scrap decreases but the quantity increases with the Mn *** the presence of Mn-containing Fe-rich particles with unique symbiotic structure can eff ectively weaken the micro-galvanic corrosion,the presence of more free Fe(Fe-rich particles)does not necessarily lead to severe corrosion of the *** corrosion susceptibility of Mg–Mn–Fe alloy primarily depends on the solubility of iron in the Mg matrix,while it can be significantly reduced by suitable Mn ***,the tolerance limit of the Fe impurity can be expressed as Femax=0.0083 Mn(relative to the iron solubility).Only when the Fe/Mn ratio is below 0.0083 can the alloy have excellent corrosion resistance,with the corrosion rate changing in the scope of 0.38±0.09 to 0.54±0.15 mg/cm^(2) day and icorr from 3 to 9×10^(–4) A/cm^(2).

关键词： Magnesium scrap Mn modification Fe impurity Corrosion susceptibility Corrosion resistance

General and efficient parallel approach of finite element-boundary integral-multilevel fast multipole algorithm

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Journal of Systems Engineering and Electronics 2008年第2期19卷 207-212页

作者： pan Xiaomin sheng Xinqing Center for Electromagnetics Simulation School of Information Science and Technology Beijing Inst. of Technology Beijing 100081 P. R. China

A general and efficient parallel approach is proposed for the first time to parallelize the hybrid finiteelement-boundary-integral-multi-level fast multipole algorithm （FE-BI-MLFMA）. Among many algorithms of FE-BI-MLFMA, the decomposition algorithm （DA） is chosen as a basis for the parallelization of FE-BI-MLFMA because of its distinct numerical characteristics suitable for parallelization. On the basis of the DA, the parallelization of FE-BI-MLFMA is carried out by employing the parallelized multi-frontal method for the matrix from the finiteelement method and the parallelized MLFMA for the matrix from the boundary integral method respectively. The programming and numerical experiments of the proposed parallel approach are carried out in the high perfor- mance computing platform CEMS-Liuhui. Numerical experiments demonstrate that FE-BI-MLFMA is efficiently parallelized and its computational capacity is greatly improved without losing accuracy, efficiency, and generality.

关键词： finite element-boundary integral-multilevel fast multipole algorithm parallelization.