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Cadaverine and putrescine exposure influence carbon and nitrogen cycling genes in water and sediment of the Yellow River

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Journal of Environmental Sciences 2024年第8期142卷 236-247页

作者： wanghong Su Qiaoling Yu Jiawei Yang Qian Han Sijie Wang Petr Hedenec Xiaochen Wang Ruijun Wan-Yan Huan Li School of Public Health Lanzhou UniversityLanzhou 730000China 2 Institute for Tropical Biodiversity and Sustainable DevelopmentUniversity Malaysia Terengganu21030Kuala NerusTerengganuMalaysia State Key Laboratory of Grassland Agro-ecosystems Center for Grassland MicrobiomeCollege of pastoral agriculture science and technology Lanzhou UniversityLanzhou 730000China

The response patterns of microbial functional genes involved in biogeochemical cycles to cadaver decay is a central topic of recent environmental ***,the response mechanisms and pathways of the functional genes associated with the carbon(C)and nitrogen(N)cycling to cadaveric substances such as cadaverine and putrescine remain *** study explored the variation of functional genes associated with C fixation,C degradation and N cycling and their influencing factors under cadaverine,putrescine and mixed *** results showed only putrescine significantly increased the alpha diversity of C fixation genes,while reducing the alpha diversity of N cycling genes in *** the C cycling,the mixed treatment significantly decreased the total abundance of reductive acetyl-CoA pathway genes(i.e.,acsB and acsE)and lig gene linked to lignin degradation in water,while only significantly increasing the hydroxypropionate-hydroxybutylate cycle(i.e.,accA)gene abundance in *** the N cycling,mixed treatment significantly decreased the abundance of the nitrification(i.e.,amoB),denitrification(i.e.,nirS3)genes in water and the assimilation pathway gene(i.e.,gdhA)in *** factors(i.e.,total carbon and total nitrogen)were all negatively associated with the genes of C and N ***,cadaverine and putrescine exposure may inhibit the pathway in C fixation and N cycling,while promoting C *** findings can offer some new insight for the management of amine pollution caused by animal cadavers.

关键词： Carbon cycling Nitrogen cycling Cadaverine Putrescine Pollution management

人口变化趋势下县域教育资源配置问题及调适方向

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北京教育学院学报 2024年第1期38卷 8-15页

作者：雷望红中南大学公共管理学院湖南长沙410004

当前,我国教育领域面临人口向城流动和出生人口减少两个层面带来的对教育资源配置的挑战。从我国县域教育资源配置实践来看,存在城乡学校建设投入错位、师资力量配置多头匮乏、生活服务设施跟进缓慢等问题。从央地关系的视角分析发现,... 详细信息

当前,我国教育领域面临人口向城流动和出生人口减少两个层面带来的对教育资源配置的挑战。从我国县域教育资源配置实践来看,存在城乡学校建设投入错位、师资力量配置多头匮乏、生活服务设施跟进缓慢等问题。从央地关系的视角分析发现,在县域教育资源配置上,中央政府、省级政府和县级政府之间存在目标张力和权力约束,导致资源分配弥散,无法回应人口变化带来的教育资源配置挑战。因此,需要对教育资源配置权进行细致界定和重新划分,建议中央政府和省级政府联合掌握资源调配权和资源监督权,省级政府和县级政府分级掌握资源统筹权,县级政府具体掌握资源分配权。这一权力分配格局既能够充分发挥中央和地方的积极性,也能够规避中央和地方在资源配置中面临的权力约束和策略局限,从而实现人口变化趋势下优化县域教育资源配置的目标。

关键词：人口变化县域教育教育资源配置央地关系

Study on Diameter Controlled Growth of Carbon Nanotubes by LaAl_(1-x)Fe_xO_3 Catalysts

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Chemical Research in Chinese Universities 2005年第1期21卷 4-7页

作者： PENGFeng wanghong-juan DepartmentofChemicalEngineering SouthChinaUniversityofTechnologyGuangzhou510640P.R.China

A series of LaAl 1-xFe xO 3 catalysts prepared with lanthanum nitrate, aluminium nitrate and iron nitrate was investigated in catalytical syntheses of carbon nanotubes with high yields and purity. The properties of carbon nanotubes prepared by the method of CVD(chemical vapor deposition) with n-hexane as the carbon resource were studied and it was shown that the diameter of carbon nanotubes can be controlled by the molar ratio of iron to aluminum in the catalysts and that the diameter of carbon nanotubes changes a little with the decrease of the iron content in the catalysts. From the TEM pictures of carbon nanotubes, it can be found that the LaAl 1-xFe xO 3 catalysts have a significant influence on the wall thickness of the carbon nanotubes, whereas they have little influence on the inner diameter of the carbon nanotubes.

关键词： Carbon nanotube LaAl1-xFexO3 Chemical vapor deposition Diameter controlled Catalyst

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中国免疫学杂志 2024年第9期40卷 1883-1888页

作者：唐津天唐润娟薛峰黎旺红新疆医科大学附属肿瘤医院肝胆胰外科二病区乌鲁木齐830054 新疆医科大学第二附属医院康复科乌鲁木齐830028

目的:探究抑制核转录因子E2相关因子2(Nrf2)途径对高糖状态下胰腺癌细胞转移及分泌免疫逃逸因子水平的影响。方法:培养人胰腺癌细胞株Panc-1,采用5.5、10、25、50 mmol/L葡萄糖处理细胞,分别于12 h、24 h、48 h通过MTT检测细胞增殖率,2... 详细信息

目的:探究抑制核转录因子E2相关因子2(Nrf2)途径对高糖状态下胰腺癌细胞转移及分泌免疫逃逸因子水平的影响。方法:培养人胰腺癌细胞株Panc-1,采用5.5、10、25、50 mmol/L葡萄糖处理细胞,分别于12 h、24 h、48 h通过MTT检测细胞增殖率,24 h时通过RT-qPCR和Western blot检测细胞内Nrf2表达变化;实验分为:对照组、高糖(HG)组、Nrf2抑制剂ML385+高糖(ML385+HG)组,MTT检测细胞增殖率,细胞克隆形成实验检测细胞集落形成数,Transwell检测细胞迁移数与侵袭数,体外划痕实验检测细胞划痕愈合情况,ELISA测定细胞培养液上清中血管内皮生长因子(VEGF)、IFN-γ、转化生长因子-β1(TGF-β1)和IL-6含量,细胞免疫荧光染色观察细胞内Nrf2分布,Western blot测定细胞中Nrf2和血红素加氧酶-1(HO-1)蛋白表达。结果:相较于5.5 mmol/L葡萄糖组,10、25、50 mmol/L葡萄糖处理12 h和24 h时Panc-1细胞增殖率升高,Nrf2 mRNA和蛋白表达均升高(P<0.05);与对照组比较,HG组细胞增殖率升高,集落形成数增加,迁移数与侵袭数均增加,划痕愈合率升高,细胞培养上清中VEGF、IFN-γ、TGF-β1和IL-6含量均增加,Nrf2荧光染色明显增强,细胞核内Nrf2表达增加,Nrf2和HO-1蛋白表达上调(P<0.05);与HG组比较,ML385+HG组细胞增殖率降低,集落形成数、迁移数与侵袭数均减少,划痕愈合率下降,培养上清中VEGF、IFN-γ、TGF-β1和IL-6含量均减少,细胞内Nrf2荧光染色较弱,Nrf2和HO-1蛋白表达下调(P<0.05)。结论:高糖状态下胰腺癌细胞中Nrf2高表达,抑制Nrf2途径能够抑制高糖促进的胰腺癌细胞增殖、迁移及侵袭,并减少免疫逃逸因子分泌。

关键词：胰腺癌高糖核转录因子E2相关因子2 免疫逃逸因子

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Network selection algorithm based on AHP and similarity

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The Journal of China Universities of Posts and Telecommunications 2018年第2期25卷 77-88,104页

作者： Li wanghong Zhu Qi Jiangsu Key Lab of Wireless Communications Nanjing University of Posts and Telecommunications

In heterogeneous wireless networks, there are various kinds of service demands from the users. A network selection algorithm based onthe analytic hierarchy process （AHP） and Similarity is proposed to solve this problem. The services are divided into three classes： Conversational Class, Streaming Class and Interactive Class. According to the characteristics of each service, a different judgment matrix is assigned and then the AHP method is used to calculate the network attribute weights. Taking the dynamic changes in user demands and network environment into account, a formula based on Lance distance for computing the attributes similarity is derived to evaluate the degree of conformity between user requirements and network attributes, from which the similarity between the user requirements and network attributes is calculated and then the total similarity by weighting. The network with the largest total similarity is the best choice. Simulation results demonstrate the effectiveness of the proposed scheme in improving the quality of service （QoS） according to the user requirements under three kinds of services.

关键词： AHP attributes similarity service type network selection

Electric and Magnetic Form Factors of Proton in Relativistic Constituent QuarkModel

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Communications in Theoretical Physics 2004年第3期41卷 425-428页

作者： wanghong-Min ZHANGBen-Ai GraduateSchool theChineseAcademyofEngineeringPhysicsBeijing100088China

Based on relativistic constituent quark (RCQ) model, the electric and magnetic form factors are analyzed. The ratio of the two form factors for the proton , which is an image of its charge and magnetization distributions, is calculated in the light-front formulism of RCQ model. Recently, this ratio was measured at the Thomas Jefferson National Accelerator Facility (JLab) using the polarization technique. The new data presented span the range and are well described by a linear Q2 fit. Also, the ratio reaches a constant value while Q2 becomes larger than 2 (GeV)2. Our calculation results are presented and appear to be consistent with the experimental ones.

关键词： form factors relativistic constituent quark model radial function

Contribution of Quark Structure Term in Nucleon Electric and Magnetic Form Factors

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Communications in Theoretical Physics 2004年第5X期42卷 735-738页

作者： wanghong-Min ZHANGBen-Ai GraduateSchool theChineseAcademyofEngineeringPhysicsBeijing100088China

The constituent quarks in the nucleon have always been considered as a point-like particle in the relativistic constituent quark model. However its calculation results of GnE agree poorly with the new experimental data. The electromagnetic structure of light front constituent quarks is considered in this paper. We find that the calculation results have good agreement with the new experimental data of GnE after considering the contribution of the quark structure term. This treatment seems to be able to improve the fit to experimental data of Gep/GMp, /Q2F2p/kpF1p,and Gen/GMn as well.

关键词：波形因数相对论夸克模型辐射方程夸克结构核子弹性电磁学

Integrated numerical model of nitrogen transportation,absorption and transformation by two-dimension in soil-crop system

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Journal of Environmental Sciences 2005年第4期17卷 662-666页

作者： wanghong-qi SHUYan QIYong-qiang ZHANGJun CollegeofWaterSciences StateKeyJointLaboratoryofEnvironmentalSimulationandPollutionControlBeijingNormalUniversityBeijing100875China

A series of simulation experiments of nitrogen transportation, absorption and transformation were conducted, and the different cropping patterns of winter wheat and wastewater irrigation plans were taken into consideration. Based on the experiments, an integrated model of crop growth, roots distribution, water and nitrogen absorption by roots, water and nitrogen movement and transformation in soil-crop system by two-dimension was developed. Parameters and boundary conditions were identified and an effective computing method for optimizing watering and wastewater irrigating plans was provided.

关键词： nitrogen absorption and movement integrated numerical model soil-crop system

黔东地区锰矿顶板基于LEC法的分类分级管理研究

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中国锰业 2024年第2期42卷 96-100页

作者：张望鸿尹江华贵州省壹零叁工程勘察施工有限责任公司贵州铜仁554300

黔东地区锰矿资源丰富,均为沉积型碳酸锰矿,矿体呈层状、似层状产出,与围岩产状基本一致。通过研究黔东地区锰矿开采揭露的顶板围岩稳固性及组合特征,归纳总结了该地区锰矿顶板围岩特征,即含锰岩系特征。根据含锰岩系特征对锰矿顶板进... 详细信息

黔东地区锰矿资源丰富,均为沉积型碳酸锰矿,矿体呈层状、似层状产出,与围岩产状基本一致。通过研究黔东地区锰矿开采揭露的顶板围岩稳固性及组合特征,归纳总结了该地区锰矿顶板围岩特征,即含锰岩系特征。根据含锰岩系特征对锰矿顶板进行分类。考虑到不同类型的巷道或采场在不同类型顶板围岩中的安全要求、时间要求、稳定性要求、允许的空顶跨度及人员密集程度等影响因素,采用作业条件危险性评价法(LEC)对不同巷道或采场的顶板围岩风险等级进行了评估,将其划分为红、橙、黄、蓝4个级别,分别对应重大风险、较大风险、一般风险和低风险。同时,将顶板危险性进行量化分级,分为Ⅰ、Ⅱ、Ⅲ、Ⅳ4个级别。针对不同风险等级的顶板,提出相应的分级管理措施,以实现顶板分级管理,有效地降低顶板事故的发生率,确保安全生产。

关键词：锰矿含锰岩系顶板分类顶板评价风险分级分级管理