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Autotoxicity of Phthalate Esters in Tobacco Root Exudates:Effects on Seed Germination and Seedling Growth

Pedosphere 2017年第6期27卷 1073-1082页

作者： DENG Jiajun ZHANG Yanling hu jiwei JIAO Jiaguo hu Feng LI huixin ZHANG Shixiang Soil Ecology Laboratory College of Resources and Environmental SciencesNanjing Agricultural UniversityNanjing 210095(China) ~hengzhou Tobacco Research Institute of CNTC Zhengzhou 450001(China) Guizhou Provincial Key Laboratory for Information System of Mountainous Areas and Protection of Ecological Environment Guizhou Nounal UniversityGuiyang 550001(China) Testing Center of Agro-Product Quality and Safety of Jiangxi Province Nanchang 330046(China) Key Laboratory of Eco-Environmental and Tobacco Leaf Quality of CNTC Zhengzhou 450001(China)

Autotoxicity is one of the major factors that impede continuous cropping.It is defined as the toxic influence of chemicals released from one plant species on the germination and growth of individuals of the same species.Here, in order to exam the autotoxicity of tobacco root exudates, root exudates were collected from tobacco plants grown both in cultural solution and on natural soil.Using ultraperformance liquid chromatography coupled with triple-quadrupole tandem mass spectrometry, main autotoxic chemical substances in the root exudates were identified.The autotoxic effects of suspected autotoxins on seed germination(including germination rate,germination potential, germination index, and vigor index) and seedling growth were analyzed.Dibutyl phthalate(or diisobutyl phthalate), dioctyl phthalate, and diisooctyl phthalate were identified in tobacco root exudates.It was observed that high concentrations(greater than 0.5 mmol L^(-1)) of each identified phthalate ester caused significant(P < 0.05) inhibition of tobacco seed germination and seedling growth.It can be concluded that phthalate esters such as dibutyl phthalate, diisobutyl phthalate, and diisooctyl phthalate in tobacco root exudates may play an important role in tobacco autotoxicity.

关键词： autotoxins germination index germination potential germination rate vigor index

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泥石流危险范围Laharz修正模型及其应用

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吉林大学学报（地球科学版） 2024年第3期54卷 905-918页

作者：文海家胡吉威张辉向学坤黄勤山地城镇建设新技术教育部重点实验室(重庆大学) 重庆400045 重庆大学库区环境地质灾害防治国家地方联合工程研究中心/土木工程学院重庆400045 重庆地质矿产研究院重庆400042

泥石流危险区研究涉及触发条件、物源与地形等多种因素,需要开发快速、有效的方法进行危险范围分析。本文基于Laharz基本原理,以泥石流样本为数据基础拟合得到修正模型,并以重庆市巫溪县杨家湾沟为例,采用修正的Laharz ArcGIS工具包,在... 详细信息

泥石流危险区研究涉及触发条件、物源与地形等多种因素,需要开发快速、有效的方法进行危险范围分析。本文基于Laharz基本原理,以泥石流样本为数据基础拟合得到修正模型,并以重庆市巫溪县杨家湾沟为例,采用修正的Laharz ArcGIS工具包,在不同降雨重现期条件下对泥石流堆积范围进行模拟计算。结果表明:1)采用修正参数使Laharz模型统计量参数的和方差(SSE)和均方根误差(RMSE)减小,确定系数(R^(2))增大,拟合优度得到明显提高;2)基于数字高程模型,结合现场调查推算的物源体积,在ArcGIS平台采用Laharz工具包可快速模拟不同降雨重现期(10、20、50、100 a)条件下的泥石流堆积范围,并且模拟泥石流堆积宽度与现场调查堆积范围接近,大部分重合;3)采用Laharz修正模型与传统的FLO-2D软件模拟进行对比,其中最远冲出距离、最大堆积宽度和堆积面积在两种方法下模拟结果的差值比率分别在10.00%、15.00%和20.00%量级,采用两种方法模拟结果与实地勘查结果也相近,表明Laharz修正模型具可靠性。

关键词：泥石流 Laharz修正模型危险范围降雨重现期

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联邦边缘智能网络碳排放评估及优化

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物联网学报 2024年第1期8卷 98-110页

作者：张鹏肖泳胡记伟廖亮吕建新白泽刚华中科技大学湖北武汉430074 烽火通信科技股份有限公司湖北武汉430074 鹏城实验室广东深圳518055 琶洲实验室(黄埔) 广东广州510555 武汉烽火技术服务有限公司湖北武汉430074

近年来,通信技术的持续演进导致通信网络的能耗显著增加。随着人工智能(AI,artificial intelligence)技术与算法在通信网络中的广泛应用和深度部署,未来6G智能通信网络架构和技术演进将对通信网络的节能减排带来更为严峻的挑战。基于边... 详细信息

近年来,通信技术的持续演进导致通信网络的能耗显著增加。随着人工智能(AI,artificial intelligence)技术与算法在通信网络中的广泛应用和深度部署,未来6G智能通信网络架构和技术演进将对通信网络的节能减排带来更为严峻的挑战。基于边缘计算和分布式联邦学习的联邦边缘智能(FEI,federated edge intelligence)网络已被普遍认为是实现6G网络内生智能的关键路径之一。然而,如何评估和优化联邦边缘智能网络的综合碳排放量仍然是一大难题。为解决该问题,首先,提出了一种联邦边缘智能网络碳排放评估框架和方法。其次,基于该评估框架和方法提出3种联邦边缘智能网络碳排放优化方案,包括动态能量交易(DET,dynamic energy trading)、动态任务分配(DTA,dynamic task allocation)和动态能量交易与任务分配(DETA,dynamic energy trading and task allocation)。最后,通过自行搭建的真实硬件平台,并利用真实世界的碳强度数据集进行联邦边缘智能网络生命周期碳排放仿真。实验结果表明,3种优化方案均能在不同场景和约束条件下显著减少联邦边缘智能网络的碳排放,为下一代智能通信网络的可持续发展和实现绿色低碳6G网络提供了依据。

关键词： 6G 碳排放联邦边缘智能网络碳排放评估框架和方法动态能量交易与任务分配

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乳腺癌患者化疗致周围神经病变的危险因素

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现代养生 2024年第10期24卷 733-737页

作者：孙丽贤胡继卫周立芝杜瑞华北理工大学唐山市人民医院

目的采用临床病例对照研究，分析乳腺癌患者化疗致周围神经病变的危险因素，为临床开展乳腺癌患者化疗致周围神经病变的防控工作提供理论依据。方法收集2022年8月-2023年6月唐山市人民医院乳腺外科化疗期间发生周围神经病变的270例乳... 详细信息

目的采用临床病例对照研究，分析乳腺癌患者化疗致周围神经病变的危险因素，为临床开展乳腺癌患者化疗致周围神经病变的防控工作提供理论依据。方法收集2022年8月-2023年6月唐山市人民医院乳腺外科化疗期间发生周围神经病变的270例乳腺癌患者为病例组，并选取同时期化疗期间未发生周围神经病变的270例乳腺癌患者为对照组。收集两组患者临床资料，通过单因素分析及多因素Logistic回归模型，探讨乳腺癌患者化疗致周围神经病变的危险因素。结果单因素分析显示，年龄、身体质量指数、化疗药物输注时间、有无固定照顾者、高血压、化疗药物累计剂量与发生周围神经病变有关（P 400mg、缺乏维生素D、谷丙转氨酶异常、化疗前贫血、化疗药物输注时间> 30分钟、身体质量指数≥24、无固定照顾者为乳腺癌患者化疗致周围神经病变的危险因素。

关键词：周围神经病变乳腺癌乳腺肿瘤危险因素

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Studies on Organic Matter and Heavy Metals in Soils around the Coal-fired Power Plant in Jinsha

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Meteorological and Environmental Research 2017年第6期8卷 56-62页

作者： Cao Rensheng Fan Mirigyi huang Xianfei Yang Hao Zhang Zedong hu jiwei Qin Farixin Guizhou Provincial Key Laboratory of Information System of Mountainous Areas and Protection of Ecological Environment Guizhou Normal UniversityGuiyang 550001China College of Forestry Guizhou UniversityGuiyang 550025China Institute of South China Karst Guizhou Normal UniversityGuiyang 550001China

The concentrations of organic matter and heavy metals( Hg,Cu,Pb,Zn,As and Cd) were analyzed in soils around the coal-fired power plant in Jinsha( Guizhou Province,China),and the ecological risks of these heavy metals were evaluated by using the ecological risk warning assessment. The results showed that the concentration of organic matter in soils was high with the average value up to 41. 54 g/kg,which met the threshold limit for the concentration of organic matter at level 1. The concentration of organic matter in the study area was above the level of lack or the level of urgency. The results from the correlation analysis showed that there were correlations between organic matter and speciation of the heavy metals( except Pb). The results from the ecological risk warning assessment showed that the order for the risk probability of individual ecological risk index above the level of no alarm was: Hg > Cu = Pb > Zn > As = Cd. The comprehensive indices revealed that the probability was 15. 62% for the sample locations at no alarm level,while the probabilities were 3. 13%,40. 63%,21. 87% and 18. 75% for sample locations at the levels of early warning,light warning,medium warning and serious warning,respectively. The results indicated that the ecological environment in this area has been adversely affected to some extent,and thus the treatment of heavy metals pollution should be strengthened in the future.

关键词： Heavy metals Organic matter Effect Warning assessment

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微RNA-454-3p、FERM结构域蛋白6在乳腺癌组织中的表达水平及临床意义

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安徽医药 2024年第6期28卷 1161-1164页

作者：张顺礼王雅琪胡继卫马杰张景华谷峥王宇唐山市人民医院乳腺外科河北唐山063001

目的探讨微RNA(miR)-454-3p、FERM结构域蛋白6(FRMD6)在乳腺癌组织中的表达水平以及临床意义。方法选取唐山市人民医院2016年12月至2018年12月住院手术的150例乳腺癌病人术中切除的乳腺癌组织标本及癌旁组织标本;采用实时荧光定量逆转... 详细信息

目的探讨微RNA(miR)-454-3p、FERM结构域蛋白6(FRMD6)在乳腺癌组织中的表达水平以及临床意义。方法选取唐山市人民医院2016年12月至2018年12月住院手术的150例乳腺癌病人术中切除的乳腺癌组织标本及癌旁组织标本;采用实时荧光定量逆转录聚合酶链反应(qRT-PCR)检测miR-454-3p、FRMD6在组织中的水平;采用Kaplan-Meier法分析miR-454-3p、FRMD6水平与乳腺癌病人预后的关系,并用log-rank法进行检验;Cox回归分析影响乳腺癌病人预后的因素。结果乳腺癌组织miR-454-3p水平(1.25±0.24)高于癌旁组织(0.99±0.22),FRMD6水平(0.79±0.19)低于癌旁组织(1.01±0.24),差异有统计学意义(P<0.05);癌组织中miR-454-3p、FRMD6水平与淋巴结转移、组织分化以及TNM分期有关(P<0.05);miR-454-3p高表达组和FRMD6低表达组病人3年累积生存率分别低于miR-454-3p低表达组和FRMD6高表达组病人(均P<0.05);miR-454-3p高表达、FRMD6低表达、TNM分期为Ⅲ/Ⅳ期、淋巴结转移是影响乳腺癌病人预后的危险因素(P<0.05)。结论miR-454-3p在乳腺癌组织中表达上调,FRMD6在乳腺癌组织中表达降低,二者与乳腺癌病人预后密切相关,有望成为临床上预测乳腺癌病人预后的生物性标志物。

关键词：乳腺肿瘤微RNA-454-3p FERM结构域蛋白6 预后临床意义

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Field test and evaluation on crop dividers of sugarcane chopper harvester

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International Journal of Agricultural and Biological Engineering 2021年第1期14卷 118-122页

作者： Jing Bai Shaochun Ma Fenglei Wang Haonan Xing Jinzhi Ma jiwei hu Beijing Key Laboratory of Optimized Design for Modern Agricultural Equipment College of EngineeringChina Agricultural UniversityBeijing 100083China

In South China,the tropical weather and climate result in severe sugarcane lodging problems which greatly hinders sugarcane mechanical harvesting.The main function of the crop divider is to lift lodged canes and facilitate base-cut cane feeding.In this study,a series of field tests were conducted on crop dividers of Liugong 4GQ-180 sugarcane chopper harvester.The tests were designed to identify the relationships of the performance index(maximum lifting height of sugarcane)and the main influencing factors(machine forward speed,rotational speed of inside scrolls,and ground clearance of crop divider toes).The single factor test was conducted to determine optimum range of these test factors:the forward speed(FS)was 2.0-4.0 km/h,the rotational speed of inside scrolls(RS)was 100-140 r/min,and the toe ground clearance(GC)was 0-5 cm.The orthogonal test(three factors and three levels)was carried out to determine the optimal combination of operating parameters:FS was 2.0 km/h,RS was 115 r/min,and GC was 0 cm.In addition,the range analysis of orthogonal test results revealed that the order of each test factor affecting crop divider performance was RS,FS,GC.This study was expected to provide valuable references for the optimal operation of sugarcane harvester crop dividers.

关键词： sugarcane chopper harvester parameter optimization machine forward speed rotational speed of scrolls ground clearance maximum lifting height field test evaluation crop divider

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Application of chemical fractionation and X-ray powder diffraction to study phosphorus speciation in sediments from Lake Hongfeng,China

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Chinese Science Bulletin 2011年第20期56卷 2098-2108页

作者： JIANG CuiHong WU Di hu jiwei LIU Feng huANG XianFei LI CunXiong JIN Mei Guizhou Provincial Key Laboratory for Information System of Mountainous Areas and Protection of Ecological Environment Guizhou Normal UniversityGuiyang 550001China

Based on the techniques of sequential extraction and X-ray powder diffraction(XRD) ,the distribution characteristics of phosphorus speciation were investigated in 13 sediment samples from Lake Hongfeng,an important drinking water source for Guiyang with a typical karstic limestone environment.The total phosphorus(TP) concentrations in the sediments ranged from 973.36 to 2334.18 mg/kg with a mean concentration of 1635.87 mg/kg(dry weight) ,and it was evident that the phosphorus level in the sediments was high compared with other eutrophic lakes such as Lake Chaohu and Lake Xihu.The results of the two methods,sequential extraction and XRD,demonstrated the presence of different phosphorus species in the lake sediments.Being compatible with local geophysical characteristics,the results of sequential extraction techniques indicate that the average percentages of dissolved phosphorus(DP) ,aluminum-bound phosphorus(Al-P) ,iron-bound phosphorus(Fe-P) ,calcium-bound phosphorus(Ca-P) and organic phosphorus(OP) in the sediments were 0.40%,7.06%,5.07%,45.48%and 38.49%,respectively.Notably,the concentrations of inorganic phosphorus(IP) were higher than those of OP,and the IP consisted primarily of Ca-P.The high concentrations of Ca-P may temporarily control the release of phosphorus from the sediments because it is a relatively stable,inert and non-bioavailable phosphorus fraction.The results of XRD analysis indicated that,among phosphorus species,AlPO4 was found in all sediment samples at relatively high concentrations.Moreover,the TP concentrations in the sediments were high;thus the release potential and bioavailability of phosphorus in the sediments was important.Further statistical analyses of the results revealed significant correlations between phosphorus species in the sediments with two extractable principal components and four selectable cluster levels allowing interpretation of possible origins of phosphorus loading and transformation mechanisms of phosphorus species.Furthermore,available remediation measures were

关键词： X射线衍射分析湖泊沉积物粉末衍射法磷形态红枫湖化学分馏地球物理特征饮用水水源

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Pursuing the goal of carbon neutrality in China:path for realization of carbon sequestration in planted forests

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Frontiers of Agricultural Science and Engineering 2024年第3期11卷 355-366页

作者： Lei DENG Haitao hu jiwei LI Xue LI Chunbo huANG Zhijing YU Hailong ZHANG Qing QU Xiaozhen WANG Lingbo DONG Zhouping SHANGGUAN State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau Northwest A&F University College of Soil and Water Conservation Science and Engineering (Institute of Soil and Water Conservation) Northwest A&F University Shaanxi Forestry Survey and Planning Institute College of Landscape Architecture Northeast Forestry University Institute of Soil and Water Conservation Chinese Academy of Sciences and Ministry of Water Resources Key Laboratory of Regional Ecology and Environmental Change School of Geography and Information EngineeringChina University of Geosciences

Tree plantations are an important forest resource that substantively contributes to climate change mitigation and carbon sequestration. As the area and standing volume of tree plantations in China have increased, issues such as unreasonable structure, low productivity, limited ecological functionality and diminishing ecological stability have occurred, which hinder the ability of tree plantations to enhance carbon sequestration. This study outlined the trajectory of carbon sequestration and its associated benefits in tree plantations by examining the current state of tree plantation establishment and growth, elucidated the strategies for advantages of carbon sequestration and climate change mitigation in planted forests, and summarized the existing problems with tree plantations. This paper underscores the pressing need for concerted efforts to boost carbon sequestration within planted forests and proposes management and development strategies for Chinese tree plantations. In the future, it will be necessary to apply scientific theories to practice and develop multi-objective management optimization models for the high-quality development of tree plantations. This will involve establishing a cohesive national carbon trading market, improving the prediction of carbon sequestration, and identifying priority zones for afforestation and reforestation, to better serve China's national strategy for achieving peak carbon and carbon neutrality.

关键词： Planted forest carbon stock carbon sequestration carbon management climate change promotion path

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Application of City Wetland Park on Protection of Urban Rivers

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环境科学前沿（中英文版） 2015年第3期4卷 77-85页

作者： Xianfei huang jiwei hu Fanxin Qin Guizhou Provincial Key Laboratory for Ecological Environment Guizhou Normal UniversityGuiyang 550001P.R.China College of forestry Guizhou UniversityGuiyang 550025P.R.China

With the rapid development of urbanization and the lack of sustainable regulation policies,large cities have become a critical pollution source to urban rivers.To elucidate the pollution status of the Nanming River,an urban river in Guiyang City,SW China,water samples were collected along the river from the upstream(through the urbanization area)to the downstream locations.Pollution levels of heavy metals,NH4+and total phosphorus(TP)were investigated,and dissolved organic matter(DOM)was analyzed with fluorescence spectrophotometer.The results reveal that huangjindadao,a local famous scenic spot,is a notable pollution source to the Nanming River,and the huaxi National City Wetland Park plays an important role in protection of the water quality of this river.Analysis of 3DEEM characteristics of DOM indicated that the main pollution sources of DOM in this water body was municipal waste water.Protein-like compounds and humic acid with high molecular weight was the main components of DOM in this river.Organic compounds with low molecular weight represented a very small portion of the DOM in water of the Nanming River,especially in the downstream part of this river.

关键词： Pollution Heavy Metals Dissolved Organic Matter Urbanization Nanming River

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