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Experimental Study on Afforestation in the Engineering Treatment Areas in the Hydro-fluctuation Zone of the Three Gorges Reservoir:A Case Study on the Engineering Treatment Area in the Wuxi Section of the Daning River
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作者 Zhengchun WANG Xiang FU +2 位作者 Haiyan JIANG Qiang XIE Hejun ZHANG 《Agricultural Biotechnology》 CAS 2022年第4期161-163,共3页
Through the Betula nigra afforestation test in the engineering treatment area of the Wuxi Section of the Daning River in Chongqing,the feasibility of arbor vegetation restoration in the comprehensive management of the... Through the Betula nigra afforestation test in the engineering treatment area of the Wuxi Section of the Daning River in Chongqing,the feasibility of arbor vegetation restoration in the comprehensive management of the engineering treatment areas of the Three Gorges Reservoir was explored.The results showed that:(1)before the flooding in the project area,the survival rate of B.nigra seedlings was high,over 95%,and(2)in 2021,after a water storage period,affected by factors such as seedling specifications,flood and flooding time,the survival rate of the seedlings planted in 2020 was low,and the one-year-old seedlings were greatly competed by weeds and grew less.Two-year-old B.nigra seedlings were replanted in 2021,and the survival rate of the B.nigra seedlings was 100%in 2022.Two-year-old B.nigra seedlings have strong adaptability and have little impact on the stability of the engineering treatment area,and can be used as afforestation tree species in engineering treatment areas of hydro-fluctuation zones. 展开更多
关键词 Hydro-fluctuation zone Engineering treatment area Vegetation restoration Water birch
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Evaluation of phosphorus removal from wastewater by soils in rural areas in China 被引量:7
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作者 Hanwen Liang, Junxin Liu, Yuansong Wei, Xuesong GuoResearch Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2010年第1期15-22,共8页
Low-cost, easy-maintenance and high-efficiency decentralized wastewater treatment technologies are urgently needed in rural areas of China. Processes with high potential for phosphorus removal are of great interest. H... Low-cost, easy-maintenance and high-efficiency decentralized wastewater treatment technologies are urgently needed in rural areas of China. Processes with high potential for phosphorus removal are of great interest. However, commonly used treatment methods often do not meet the strict criteria for removing phosphorus from rural wastewater. In order to search an economic and simple technology for phosphorus removal from the common bit-technologies effluent, seven soil types collected from different rural areas in China were investigated for their ability to remove phosphorus. X-ray diffraction (XRD) was used to analyse the mineral structure, and inductively coupled plasma optical emission spectrometer (ICP-OES) was used to analyse the geochemical composition of the soil samples. Three primary minerals - quartz, albite and montmorillonite - were clearly detected. The samples were divided into two soil types, acidic soils and alkaline soils, based on their pH values. The geochemical composition study indicated that a higher percentage of Ca and Mg occurred in alkaline soils (pH 〉 8) than in acidic soils (pH 〈 6.5). Adsorption isotherms from batch experiments fitted the Langmuir and Freundlich models well, the maximum P adsorption capacities ranged from 0.256 to 1.598 mg P/g, indicating a high phosphorus removal potential for all of these soils. The P fractions extracted revealed that the sum of NaOH-extracted inorganic P (NaOH-Pi) was the major P component in the acidic soils, and CaCO3-bound phosphorus (Ca-P) in the alkaline soils. Dynamic adsorption simulation showed that these soils have the ability to remove phosphorus from wastewater. 展开更多
关键词 ADSORPTION phosphorus removal rural areas wastewater treatment
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Instability identification on large scale underground mined-out area in the metal mine based on the improved FRBFNN 被引量:4
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作者 Luo Zhouquan Zuo Hongyan +1 位作者 Jia Nan Wang Yiwei 《International Journal of Mining Science and Technology》 SCIE EI 2013年第6期821-826,共6页
To identify the instability on large scale underground mined-out area in the metal mine effectively,the parameters of radial basis function were determined through clustering method and the improved fuzzy radial basis... To identify the instability on large scale underground mined-out area in the metal mine effectively,the parameters of radial basis function were determined through clustering method and the improved fuzzy radial basis function neural network(FRBFNN)model of instability identification model about large scale underground mined-out area in the metal mine was built.The improved FRBFNN model was trained and tested.The results show that the improved FRBFNN model has high training accuracy and generalization ability.Parameters such as pillar area ratio,filling level and the value of rock quality designation have strong influence on instability of large scale underground mined-out area.Correctness of analysis about the improved FRBFNN model was proved by the practical application results about instability discrimination of surrounding rock in large-scale underground mined-out area of a metal mine in south China. 展开更多
关键词 Metal mine Fuzzy theory mined-out area RBF neural network DISCRIMINATION
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Quantitative analysis of biotechnical reinforcement for a steep slope consisting of composite coal-gangue-soil medium adjacent to a mined-out area 被引量:3
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作者 Xingping Lai Mowen Xie +1 位作者 Fenhua Ren Meifeng Cai 《Journal of University of Science and Technology Beijing》 CSCD 2005年第6期489-494,共6页
The engineering and geological characteristics of a steep slope consisting of coal gangue, rock and soil medium in Huating coal mine have been comprehensively investigated. Owing to humid weather, heavy rainfall, vege... The engineering and geological characteristics of a steep slope consisting of coal gangue, rock and soil medium in Huating coal mine have been comprehensively investigated. Owing to humid weather, heavy rainfall, vegetation and porous characteristics of the soil and rock mass, the steep slope will be destabilized and induce mud-rock flow or derive hazard easily. Firstly, based on the classical slope reinforcement theory, some regularity between the shear and displacement in the destabilized zone of the slope with or without root strength contribution is presented. Then, based on the experimental and statistical analysis of root strength, hydrological characteristics and stability status, etc., some possible biotechnical techniques for reinforcement of the steep slope have been suggested. These methods are important for quantitative analysis of destabilization of the slope and design of the biotechnical reinforcement. 展开更多
关键词 mined-out area coal-gangue-soil composite medium steep slope root-soil effect biotechnical reinforcement
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Time function of surface subsidence based on Harris model in mined-out area 被引量:7
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作者 Liu Xinrong Wang Junbao +2 位作者 Guo Jianqiang Yuan Hong Li Peng 《International Journal of Mining Science and Technology》 SCIE EI 2013年第2期251-254,共4页
The surface subsidence is a common environmental hazard in mined-out area. Based on careful analysis of the regularity of surface subsidence in mined-out area, we proposed a new time function based on Harris curve mod... The surface subsidence is a common environmental hazard in mined-out area. Based on careful analysis of the regularity of surface subsidence in mined-out area, we proposed a new time function based on Harris curve model in consideration of the shortage of current surface subsidence time functions. By analyzing the characteristics of the new time function, we found that it could meet the dynamic process, the velocity change process and the acceleration change process during surface subsidence. Then its rationality had been verified through project cases. The results show that the proposed time function model can give a good reflection of the regularity of surface subsidence in mined-out area and can accurately predict surface subsidence. And the prediction data of the model are a little greater than measured data on condition of proper measured data quantity, which is safety in the engineering. This model provides a new method for the analysis of surface subsidence in mined-out area and reference for future prediction, and it is valuable to engineering application. 展开更多
关键词 mined-out area Surface subsidence Time function Harris model Prediction
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Relationship between body surface area and ALT normalization after long-term lamivudine treatment 被引量:1
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作者 Makoto Nakamuta Shusuke Morizono +14 位作者 Yuichi Tanabe Eiji Kajiwara Junya Shimono Akihide Masumoto Toshihiro Maruyama Norihiro Furusyo Hideyuki Nomura Hironori Sakai Kazuhiro Takahashi Koichi Azuma Shinji Shimoda Kazuhiro Kotoh Munechika Enjoji Jun Hayashi Kyushu University liver Disease Study Group 《World Journal of Gastroenterology》 SCIE CAS CSCD 2005年第44期6948-6953,共6页
AIM: To further evaluate the relationship between BSA and the effects of lamivudine in a greater number of cases and over a longer period of observation than in our previous evaluation.METHODS: We evaluated 249 patien... AIM: To further evaluate the relationship between BSA and the effects of lamivudine in a greater number of cases and over a longer period of observation than in our previous evaluation.METHODS: We evaluated 249 patients with chronic hepatitis B. The effects of treatment for one year (n = 249),two years (n = 147), and three years (n = 72) were evaluated from the levels of serum ALT and HBV-DNA,as biological and virological effects (undetectable levels by PCR), respectively. Moreover, several variables that could influence the response to treatment, including ALT,albumin, bilirubin, platelet counts, BSA, HBV-DNA, and HBeAg were analyzed.RESULTS: For 1-year treatment, multivariate analysis revealed that BSA (P=0.0002) was the only factor for the biological effect, and that ALT (P = 0.0017), HBVDNA (P = 0.0004), and HBeAg (P = 0.0021) were independent factors for the virological effect. For 2-year treatment, multivariate analysis again showed that BSA(P = 0.0147) was the only factor for the biological effect,and that ALT (P = 0.0192) and HBeAg (P = 0.0428) were independent factors for the virological effect. For 3-year treatment, multivariate analysis, however, could not reveal BSA (P = 0.0730) as a factor for the normalization of ALT levels.CONCLUSION: BSA is a significant predictor for the normalizing the effect of lamivudine therapy on ALT for an initial 2-year period, suggesting that lamivudine dosage should be based on the individual BSA. 展开更多
关键词 乙型肝炎病毒 治疗 表面抗体 ALT
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Significance of Substrate Selection in the Efficiency of Wastewater Treatment in Constructed Wetlands (CWs)
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作者 Snezana Didanovic Danijel Vrhovsek 《Journal of Water Resource and Protection》 2023年第9期424-441,共18页
Constructed wetlands (CWs) can achieve a high-quality wastewater treatment and a quality that meets the prescribed standard, defined by legislation on wastewater discharge. A limitation in the application of construct... Constructed wetlands (CWs) can achieve a high-quality wastewater treatment and a quality that meets the prescribed standard, defined by legislation on wastewater discharge. A limitation in the application of constructed wetlands (CWs) is the large area requirement, which limits their application. The subject matter of this research is to check the possibility of improving the efficiency of wastewater treatment and reducing the required area for constructed wetlands (CWs) by using an adequate substrate under the conditions found in Montenegro. In the described experiment, the constructed wetlands (CW) have a vertical flow system and play the role of a secondary wastewater treatment, receiving water from the existing WWTP in Podgorica after the primary treatment. These vertical flow systems reflect experience with the use of similar systems in Slovenija, Austria and Italy. Measurements to date show that the substrate plays an important role and that wastewater treatment efficacy varies significantly with respect to the type of substrate when used under the conditions available in Montenegro. 展开更多
关键词 Constructed Wetlands (CW) Reduced area of Wetlands Substrates for Wetlands Vertical Flow System Primary treatment treatment Efficacy
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Assessing the effects of alternative fuel treatments to reduce wildfire exposure
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作者 Roghayeh Jahdi Liliana Del Giudice +4 位作者 Massimo Melis Raff aella Lovreglio Michele Salis Bachisio Arca Pierpaolo Duce 《Journal of Forestry Research》 SCIE CAS CSCD 2023年第2期373-386,共14页
Effective landscape-scale fuel management strategies are essential for reducing wildfire risk in Mediterranean fire-prone areas.In this study,the minimum travel time(MTT)fire-spread algorithm as implemented in FlamMap... Effective landscape-scale fuel management strategies are essential for reducing wildfire risk in Mediterranean fire-prone areas.In this study,the minimum travel time(MTT)fire-spread algorithm as implemented in FlamMap was applied to assess the potential of alternative fuel treatments for lowering wildfire losses in a 5,740-ha study area in eastern Sardinia,Italy.Twenty-seven wildfires at 10-m resolution were simulated considering three wind speeds(15,18,and 21 km h-1)to compare fuel treatments:no treatment(NT),irrigated agroforestry areas with shrub clearing(T1),prescribed fire in eucalyptus stands(T2),and irrigated grasslands(T3).The simulations replicated a recent large wildfire that occurred in the study area(Orrìwildfire,2019)and considered the weather and fuel moisture conditions associated with this event.The average wildfire exposure outputs(burned area,probability of burning,conditional flame length,potential crown fire occurrence,and surfaces withflame lengths above 2.5 m)decreased after fuel treatments,compared to no treatment.T1 was the most effective strategy in mitigating wildfire hazards and provided the most significant performance for several wildfire exposure indicators.Treating only 0.5%of the study area(~30 ha)resulted in a decrease in all wildfire exposure metrics to~10%within the study area.In addition,the total surface characterized by high flame length(average>2.5 m)was the lowest in the T1 treatment.This study can help land and fire managers optimize fuel treatment opportunities and wildfire risk mitigation strategies in Mediterranean areas. 展开更多
关键词 Fuel treatment strategies Fire prevention Mediterranean areas Minimum travel time(MTT) Wildfi re exposure
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岩溶凹陷式露天矿山大流量涌水治理技术
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作者 李海燕 夏茂哲 +6 位作者 张锟 张波 孙怀凤 赵国东 韩俊飞 刘功杰 贺恩磊 《煤炭科学技术》 EI CAS CSCD 北大核心 2024年第1期267-279,共13页
我国岩溶地质分布广泛,岩溶突涌水已成为石灰石矿山安全生产的巨大灾害与挑战。以广西某岩溶凹陷式露天矿山大流量涌水为研究对象,针对该矿山地质条件复杂、集中涌水量大、流速高等特点,利用岩溶发育特征、资料分析与地球物理探查等方... 我国岩溶地质分布广泛,岩溶突涌水已成为石灰石矿山安全生产的巨大灾害与挑战。以广西某岩溶凹陷式露天矿山大流量涌水为研究对象,针对该矿山地质条件复杂、集中涌水量大、流速高等特点,利用岩溶发育特征、资料分析与地球物理探查等方法初步圈定矿山径流带区域;进一步通过钻探、跨孔CT和示踪联通试验等精准查找到矿山Y01特大涌水点岩溶管道的具体位置,在此基础上研究并实施了矿山涌水治理技术与工艺。研究表明:(1)针对复杂岩溶凹陷式露天矿山大流量、高流速的涌水特征,提出并实施了“非连续帷幕截流+关键通道探查与封堵+止浆垫控流降速”的岩溶矿山涌水综合治理体系。依据岩溶发育的不均匀性,提出了非连续帷幕封堵裂隙型涌水区域的思想;对大流量岩溶管道型集中涌水设计采用止浆垫控流装置,通过控流能有效降低关键过水通道内水流速度,为注浆材料的有效留存沉积和工程的成功封堵提供了重要条件。(2)关键孔联合注浆工艺是岩溶管道型涌水成功封堵的保证,关键孔是指直接揭露岩溶涌水管道或与涌水管道联通性极强并对注浆堵水起主要作用的钻孔。针对矿山Y01岩溶管道型特大涌水精准查找到2个关键孔,均在矿坑南部:一个是距涌水点直线距离约50 m的近距离钻孔(以下简称“近孔”),另一个是距涌水点直线距离约150 m的远距离钻孔(以下简称“远孔”)。现场采用近孔、远孔2个关键孔联合注浆工艺:近孔以粗骨料和自主研发的可控凝结新型材料进行注浆,远孔仅注水泥浆液;近孔粗骨料和新型材料既能降低管道内的水流速度为远孔浆液起到更好的留存沉积作用,又能作为封堵材料起到增强的功能,远孔因其离涌水点距离长、辐射范围广、浆液扩散充分而能确保封堵长度和效果。近孔、远孔协同配合同步注浆是封堵管道型大流量涌水的有效组合工艺。(3)涌水口止浆垫控流降速装置的合理有效调控,配合关键孔联合注浆工艺的同步实施,进一步确保了注浆浆液的有效快速留存和沉积,是岩溶地区封堵管道型大流量涌水的创新性技术和方法。项目实施后,彻底封堵矿坑内集中涌水量达7.12万m^(3)/d的Y01特大涌水点,实现总减水量8.43万m3/d(含非连续帷幕注浆封堵),保证了矿山的正常安全开采,大幅降低了抽排水费用,同时保护了周边环境和地下水资源,具有显著的经济效益和社会效益。研究成果可为我国矿山涌水灾害治理提供理论价值和经验借鉴。 展开更多
关键词 岩溶地区 涌水治理 关键通道 非连续帷幕 控流降速
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高密度建成区污水治理提升规划与实施体系研究
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作者 王宁 郭繁锦 +2 位作者 曾坚 甘硕儒 丁锶湲 《城市规划》 CSCD 北大核心 2024年第2期94-102,共9页
污水处理提质增效是存量规划背景下城市更新的重要内容,是改善城市人居生态环境的有效路径。结合城市可持续发展、高质量发展的新要求,以厦门市思明区为研究对象,提出了排水现状排查和数字化的技术方法,探索总结了高密度建成区“溯源排... 污水处理提质增效是存量规划背景下城市更新的重要内容,是改善城市人居生态环境的有效路径。结合城市可持续发展、高质量发展的新要求,以厦门市思明区为研究对象,提出了排水现状排查和数字化的技术方法,探索总结了高密度建成区“溯源排查、正本清源、排水管理进小区”污水治理提升规划模式。借助“多规合一”的国土空间规划体系,针对性地提出技术标准、实施细则和政策规章等配套措施,建立了污水治理系统“智慧型”信息管理平台,构建了完善的规划实施体系,有效统筹了高密度建成区污水治理的“规划、建设、管理”三大环节,为新时期推动污水治理体系和治理能力现代化提供新思路。 展开更多
关键词 污水治理提升 国土空间规划 实施体系 高密度建成区
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富水沟谷区浅埋煤层导水裂隙演化特征
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作者 来兴平 乔浩 +4 位作者 单鹏飞 吴龙泉 朱浩宇 赵浩州 戴自强 《煤炭科学技术》 EI CAS CSCD 北大核心 2024年第4期1-11,共11页
富水沟谷区域下浅埋煤层赋存条件特殊,采场上覆岩层导水裂隙发育演化特征复杂。为了揭示沟谷区浅埋煤层在回采扰动作用下覆岩裂隙演化规律,以朱家峁煤矿1305-2工作面过沟谷区回采阶段为工程背景,采用理论分析、物理相似模拟、数值模拟... 富水沟谷区域下浅埋煤层赋存条件特殊,采场上覆岩层导水裂隙发育演化特征复杂。为了揭示沟谷区浅埋煤层在回采扰动作用下覆岩裂隙演化规律,以朱家峁煤矿1305-2工作面过沟谷区回采阶段为工程背景,采用理论分析、物理相似模拟、数值模拟与现场效果验证的方法,建立了覆岩裂隙−渗流场概念模型,开展了覆岩结构发育与微震能量演化研究,分析了覆岩变形与塑性破坏分布特征,提出了针对沟谷区下浅埋煤层导水裂隙防治措施,并应用于现场工程实践。结果表明:开采扰动下裂隙−渗流场模型呈“梯台”结构,并依次划分为初渗区域、稳渗区域、紊渗区域3个区域;将所研究矿井的工况数据代入模型结构,计算出各个渗透区域范围,并根据计算结果对矿井的稳渗区域采取注浆措施。工作面回采至沟谷区段,覆岩裂隙域形态呈现“拱形-梯形-复合梯形”的扩展演化特征,裂隙纵向发育高度达到163 m,并与沟谷区地表贯通。随工作面推进,地表裂隙依次经历“滑移-挤压-撕裂”过程;沟谷区域位移云图呈现出滞后开采“高位梯形”破断形态,在沟底处下沉位移最大,达3.47 m。针对开采导致的裂隙大范围扩展贯通,提出在地面进行采动裂缝注浆处理,在工作面上覆岩层进行注浆封堵,实现过沟谷区开采“井上−井下”联合防治,保证安全开采。该研究结果可为浅埋煤层的过沟谷区开采、采动裂隙防治及富水区“保水采煤”提供新的科学依据。 展开更多
关键词 浅埋煤层 覆岩裂隙 发育形态 裂隙治理 沟谷区开采
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安徽琅琊山风景区某崩塌的特征分析及治理措施
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作者 赵志根 王康东 杜伟 《河南科技》 2024年第2期112-115,共4页
【目的】分析安徽琅琊山风景区某崩塌隐患点的特征并提出治理措施。【方法】采用现场调研、地形测绘、三维激光扫描仪、稳定性评价等手段,获得该崩塌点的特征和稳定性。【结果】该崩塌点具备倾倒式崩塌的特征,4个主要危岩体都是处于不... 【目的】分析安徽琅琊山风景区某崩塌隐患点的特征并提出治理措施。【方法】采用现场调研、地形测绘、三维激光扫描仪、稳定性评价等手段,获得该崩塌点的特征和稳定性。【结果】该崩塌点具备倾倒式崩塌的特征,4个主要危岩体都是处于不稳定或欠稳定状态。【结论】采用设置锚杆、支撑墙、水泥浆充填等方法对危岩体进行加固,并采用人工清除松动石块、发挥截水沟的作用等方法进行治理,能够消除崩塌隐患,确保景点安全和景观价值。 展开更多
关键词 琅琊山风景区 崩塌 特征 稳定性评价 治理
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河谷区多层软土地基强夯处治分析 被引量:1
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作者 周静 《北方交通》 2024年第4期75-78,82,共5页
文章依托高速公路多层软土地基强夯处治项目,在施工现场选取具有代表性的监测断面开展现场监测,检验河谷区多层软土地基强夯处治效果。由监测数据得出,在强夯处治和路基填筑施工阶段,地基分层沉降、土压力、孔隙水压力和侧向位移增幅均... 文章依托高速公路多层软土地基强夯处治项目,在施工现场选取具有代表性的监测断面开展现场监测,检验河谷区多层软土地基强夯处治效果。由监测数据得出,在强夯处治和路基填筑施工阶段,地基分层沉降、土压力、孔隙水压力和侧向位移增幅均较大,工后逐渐趋于稳定,可说明强夯处治后软基承载力得到有效提升,路基整体结构稳定,加固效果良好。 展开更多
关键词 河谷区 软土地基 强夯处治 分层沉降 侧向位移
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单侧双通道内镜治疗重度腰椎管狭窄症的近期疗效分析
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作者 占允中 杨帆 +4 位作者 叶舟 赵梓汝 刘华飞 吴以臣 黄伟铖 《浙江医学》 CAS 2024年第12期1300-1304,共5页
目的探讨单侧双通道内镜治疗重度腰椎管狭窄症的近期疗效及对患者硬膜囊面积、功能恢复情况的影响。方法前瞻性选取2021年1月至2023年1月衢州市人民医院收治的重度腰椎管狭窄症患者60例为研究对象,采用随机数字表法分为观察组和对照组,... 目的探讨单侧双通道内镜治疗重度腰椎管狭窄症的近期疗效及对患者硬膜囊面积、功能恢复情况的影响。方法前瞻性选取2021年1月至2023年1月衢州市人民医院收治的重度腰椎管狭窄症患者60例为研究对象,采用随机数字表法分为观察组和对照组,各30例。观察组实施单侧双通道内镜技术,对照组实施传统腰椎后路椎板开窗减压术,比较两组患者手术效果、硬膜囊面积变化、功能恢复及并发症发生情况。结果观察组患者总优良率为93.33%,高于对照组的73.33%,差异有统计学意义(P<0.05)。与术前比较,术后1个月两组患者硬膜囊面积均增大,且观察组大于对照组,差异均有统计学意义(均P<0.05)。与术前比较,术后3个月两组患者日本骨科协会腰痛评分均升高,Oswestry功能障碍指数均降低,且观察组均上述指标均优于对照组,差异均有统计学意义(均P<0.05)。观察组和对照组并发症发生率分别为10.00%和20.00%,两组比较差异无统计学意义(P>0.05)。结论单侧双通道内镜治疗重度腰椎管狭窄症近期疗效显著,可明显减轻患者术后疼痛程度,改善患者腰椎功能。 展开更多
关键词 重度腰椎管狭窄症 单侧双通道内镜治疗 近期疗效 硬膜囊面积 功能恢复情况
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煤矿矿区土壤重金属及多环芳烃污染治理修复技术综述 被引量:1
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作者 花洁 王健媛 +3 位作者 陈运帷 王健 陈征 刘洋洋 《环境工程技术学报》 CAS CSCD 北大核心 2024年第1期139-147,共9页
土壤重金属和有机物污染是当前许多煤矿矿区及周边地区面临的严重问题,威胁居民健康,要采取有效措施予以解决。在对煤矿矿区周边土壤重金属和多环芳烃(PAHs)来源及危害分析的基础上,发现重金属元素在自然条件下难以降解,导致其在生物体... 土壤重金属和有机物污染是当前许多煤矿矿区及周边地区面临的严重问题,威胁居民健康,要采取有效措施予以解决。在对煤矿矿区周边土壤重金属和多环芳烃(PAHs)来源及危害分析的基础上,发现重金属元素在自然条件下难以降解,导致其在生物体中累积,并且PAHs具有致癌性、致畸性和诱变性。通过比较物理化学修复、植物修复和生物修复等方法在治理重金属及PAHs污染土壤的优缺点,发现植物修复和生物修复对气候和环境的依赖程度高,物理修复成本和能耗较高,因此提出矿区周边土壤污染的修复技术需要进一步创新,实现多领域、多学科协作发展的观点。通过持续的技术创新和多种修复方法的联合应用,达到有效治理煤矿矿区及周边重金属和PAHs污染的目的,实现土壤的重新利用,进而实现环境保护与经济可持续发展的良性互动。 展开更多
关键词 土壤污染 煤矿矿区 重金属 多环芳烃(PAHs) 土壤治理修复
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基于深度学习的蔬菜田精准除草作业区域检测方法
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作者 李卫丽 金小俊 +1 位作者 于佳琳 陈勇 《福建农业学报》 CAS CSCD 北大核心 2024年第2期199-205,共7页
【目的】蔬菜生长随机,杂草种类众多。传统杂草识别算法复杂,且仅识别出杂草,未能精准确定除草作业区域。本研究以蔬菜及其伴生杂草为研究对象,拟探索一种基于深度学习的杂草识别与精准除草作业区域检测方法。【方法】通过将原图切分网... 【目的】蔬菜生长随机,杂草种类众多。传统杂草识别算法复杂,且仅识别出杂草,未能精准确定除草作业区域。本研究以蔬菜及其伴生杂草为研究对象,拟探索一种基于深度学习的杂草识别与精准除草作业区域检测方法。【方法】通过将原图切分网格图像,利用深度学习模型识别蔬菜、杂草及土壤,将包含杂草的网格图像标记为除草作业区域。选取ShuffleNet、DenseNet和ResNet模型开展识别试验,并采用精度、召回率、F_(1)值和总体准确率、平均准确率分别对验证集和测试集进行评价分析。【结果】所选的3种网络模型均能较好地识别杂草和蔬菜,其中ShuffleNet为杂草识别最优模型,其对杂草的识别具有较为均衡的精度和召回率,分别为95.5%、97%,且其识别速度也达最优,为68.37 fps,能够应用于实时杂草识别。【结论】本研究提出的除草作业区域检测方法具有高度的可行性和极佳的识别效果,可用于蔬菜田间杂草的精准防除。 展开更多
关键词 蔬菜 杂草 图像处理 深度学习 作业区域检测
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江苏省农村惊厥性癫痫患者治疗缺口分析
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作者 孙方玲 余传勇 +5 位作者 李炎章 李亦涵 王英藩 王思懿 许峰源 王小姗 《临床神经病学杂志》 CAS 2024年第1期20-25,共6页
目的探讨江苏省农村地区惊厥性癫痫的治疗缺口以及影响因素。方法对2005—2020年筛查的7836例农村惊厥性癫痫患者的临床资料进行统计,分析癫痫患者的治疗现状、治疗缺口以及相关的影响因素。结果本研究共入组7836例惊厥性癫痫患者。江... 目的探讨江苏省农村地区惊厥性癫痫的治疗缺口以及影响因素。方法对2005—2020年筛查的7836例农村惊厥性癫痫患者的临床资料进行统计,分析癫痫患者的治疗现状、治疗缺口以及相关的影响因素。结果本研究共入组7836例惊厥性癫痫患者。江苏省农村地区惊厥性癫痫的治疗缺口为69.05%。不同性别间的治疗缺口差异无统计学意义(P>0.05);不同年龄段(χ^(2)=12.196,P=0.007)、不同首发年龄患者(χ^(2)=58.658,P<0.001)、不同病程(χ^(2)=65.430,P<0.001)、不同发作次数(χ^(2)=171.276,P<0.001)、不同就诊医院级别(χ^(2)=122.076,P<0.001)的治疗缺口差异有统计学意义。多因素Logistic回归分析显示,首发年龄越大、病程越短、发作越频繁,癫痫患者的治疗缺口越大(均P<0.05)。在患病年龄和就诊医院上,45~59岁(P=0.012)以及就诊于市县级医院(P<0.001)的患者更倾向于接受正规抗癫痫治疗。结论江苏省农村地区惊厥性癫痫患者的治疗缺口较大。主要原因可能是对癫痫的认识不足以及基层医院建设滞后。 展开更多
关键词 惊厥性癫痫 农村地区 治疗缺口 现状调查
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运动改善甲基苯丙胺戒断者抑制控制和药物渴求的机制
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作者 廖帅雄 邓开 +4 位作者 白楠 杨文亮 王丰 郝宗继 李雪莹 《中国组织工程研究》 CAS 北大核心 2024年第27期4390-4396,共7页
背景:抑制控制和药物渴求是评估甲基苯丙胺成瘾者药物戒断的核心要素,备受学界关注。众所周知,要彻底实现对药物成瘾的戒断,恢复吸毒者受损的抑制控制功能,有效降低对药物的渴求是关键。目的:旨在通过系统分析运动与甲基苯丙胺戒断者抑... 背景:抑制控制和药物渴求是评估甲基苯丙胺成瘾者药物戒断的核心要素,备受学界关注。众所周知,要彻底实现对药物成瘾的戒断,恢复吸毒者受损的抑制控制功能,有效降低对药物的渴求是关键。目的:旨在通过系统分析运动与甲基苯丙胺戒断者抑制控制和药物渴求的关系,找出促进甲基苯丙胺成瘾戒断的有效运动干预方案,并进一步探究运动作用的内在机制,以期为未来运动运用于毒品戒断提供理论上的支持和应用上的参考。方法:通过检索中国知网、万方、维普、Web of Science及PubMed数据库,中文检索词为“运动,体育锻炼,甲基苯丙胺,抑制功能,渴求度,成瘾”等,英文检索词为“Sport*,Exercise,Methamphetamine,Drug craving,Executive function,Addiction”等,依据纳入和排除标准对文献进行筛选,最终获得目标文献65篇进行综述分析。结果与结论:①运动对甲基苯丙胺戒断者抑制控制方面,急性和长期中等强度有氧运动或急性中高强度间歇训练均能够显著提升甲基苯丙胺戒断者抑制控制能力,对于长期有氧运动而言,有氧操课练习或全身性的综合练习效果更佳,若运动形式为功率自行车,建议增加运动干预频次。②运动对甲基苯丙戒断者药物渴求度方面,急性中等强度有氧运动和抗阻力训练或长期中等强度、高强度或递增负荷的有氧及抗阻力训练均能够有效降低甲基苯丙胺戒断者的药物渴求度。③运动对甲基苯丙胺介导的机体成瘾具有内在调控作用,首先,运动可通过影响大脑腹侧被盖区酪氨酸羟化酶的表达,进而刺激多巴胺受体偶联蛋白的表达,促进大脑奖赏区域多巴胺的合成,弥补由于甲基苯丙胺成瘾导致的多巴胺耗竭;其次,运动也可通过调控蛋白激酶A抑制剂,影响多巴胺D1受体介导的蛋白激酶A信号通路,通过抑制蛋白激酶A从而影响环磷酸腺苷反应结合蛋白,实现对甲基苯丙胺成瘾的调控;最后,运动也可在基因水平上通过影响大脑红核区细胞c-fos基因的表达,激活该区域谷氨酸神经元亚群,产生奖赏效应,实现对甲基苯丙胺成瘾的改善。④虽然目前研究已证实运动与甲基苯丙胺成瘾的关系,且已明晰运动作用的脑内机制,但是否还存在运动作用的其他脑内调控途径有待通过设计更为科学、严谨的动物或人体实验,从细胞或分子学水平出发进行深入探究。 展开更多
关键词 运动 甲基苯丙胺 成瘾 抑制控制 药物渴求 治疗 神经可塑性 多巴胺 谷氨酸 伏隔核
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功能区胶质瘤外科辅助技术进展
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作者 田落意 程传东 +2 位作者 钱中润 彭楠 计颖 《临床神经外科杂志》 2024年第1期95-98,共4页
大脑功能区胶质瘤在手术过程中经常会损伤锥体束或弓状束、运动皮质等重要功能结构,这些功能结构受损后可导致术后肢体瘫痪、视野缺损、失语、认知障碍等神经功能缺失。最大限度安全切除肿瘤不但可以延长脑胶质瘤患者的总体生存期和无... 大脑功能区胶质瘤在手术过程中经常会损伤锥体束或弓状束、运动皮质等重要功能结构,这些功能结构受损后可导致术后肢体瘫痪、视野缺损、失语、认知障碍等神经功能缺失。最大限度安全切除肿瘤不但可以延长脑胶质瘤患者的总体生存期和无进展生存期,还能提高患者术后生存质量。然而,由于肿瘤位于或者邻近功能区,如何能在保护患者神经功能不受损的前提下最大限度切除功能区胶质瘤,至今仍是神经外科领域的难题。随着科学技术的发展,功能区胶质瘤的手术治疗技术也有了快速发展,本文从术中荧光、术中超声、术中唤醒麻醉、术中核磁共振成像等方面对功能区胶质瘤近年来手术治疗技术进展进行综述。 展开更多
关键词 胶质瘤 功能区 手术治疗
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复杂艰险山区高速铁路慢行病害特征与治理
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作者 张营旭 蒋良文 +4 位作者 张广泽 周波 刘小莎 罗星文 黄华 《中国铁路》 北大核心 2024年第1期30-37,共8页
针对我国西南复杂艰险山区高速铁路建设与运营中路基、桥梁和隧道出现导致列车运行速度减慢的病害(慢行病害),依托南昆、沪昆、西成高铁3条复杂艰险山区高速铁路运营期间监测与补充勘察资料,分析不同慢行病害的危害方式与变形破坏特征,... 针对我国西南复杂艰险山区高速铁路建设与运营中路基、桥梁和隧道出现导致列车运行速度减慢的病害(慢行病害),依托南昆、沪昆、西成高铁3条复杂艰险山区高速铁路运营期间监测与补充勘察资料,分析不同慢行病害的危害方式与变形破坏特征,研究高速铁路慢行病害产生的原因,提出治理方案。研究得出结论:地层岩性、地形地貌、构造应力环境、气候降雨、岩体结构条件等多重因素造成复杂艰险山区高速铁路出现路基基底上拱、斜坡桥梁位移、隧道基底上拱、隧道混凝土腐蚀等慢行病害,针对不同慢行病害提出多种治理方案。研究成果可为复杂艰险山区高速铁路工程建设、运营维护提供借鉴。 展开更多
关键词 复杂艰险山区 高速铁路 慢行病害 路基变形 桥梁位移 隧道病害 病害治理 地质灾害
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