目的对比无机三氧化物聚合物(MTA)、iRoot BP Plus在难治性前牙根尖周病患者根管治疗中的应用效果。方法选取2016年3月—2018年3月承德医学院附属医院口腔科收治的246例难治性前牙根尖周病患者,均为单颗患病且实施根管倒充填治疗。其中8...目的对比无机三氧化物聚合物(MTA)、iRoot BP Plus在难治性前牙根尖周病患者根管治疗中的应用效果。方法选取2016年3月—2018年3月承德医学院附属医院口腔科收治的246例难治性前牙根尖周病患者,均为单颗患病且实施根管倒充填治疗。其中82例患者采用MTA治疗(MTA组),84例患者采用iRoot BP Plus治疗(iRoot BP Plus组),80例患者接受氢氧化钙糊剂治疗(对照组)。对比根充质量、治疗前和治疗1周后局部红肿、疼痛评分,不同时刻旧根尖指数(O-PAI)变化及临床疗效。结果iRoot BP Plus组适充率较MTA组和对照组高(P<0.05)。MTA组治疗前和治疗1周后局部红肿、疼痛评分的差值较对照组高(P<0.05),iRoot BP Plus组最高(P<0.05)。iRoot BP Plus组O-PAI评级较MTA组、对照组低(P<0.05),相对效果较好;MTA组治疗后较对照组低(P<0.05),相对效果较好。iRoot BP Plus组临床总有效率最高(P<0.05)。结论在难治性前牙根尖周病患者根管治疗中MTA、iRoot BP Plus均优于氢氧化钙糊剂,且应用iRoot BP Plus可保证适充率,并有效减轻局部红肿、疼痛,改善O-PAI,疗效理想,有望替代MTA推广应用。展开更多
How to control the dynamic behavior of large-scale artificial active matter is a critical concern in experimental research on soft matter, particularly regarding the emergence of collective behaviors and the formation...How to control the dynamic behavior of large-scale artificial active matter is a critical concern in experimental research on soft matter, particularly regarding the emergence of collective behaviors and the formation of group patterns. Centralized systems excel in precise control over individual behavior within a group, ensuring high accuracy and controllability in task execution. Nevertheless, their sensitivity to group size may limit their adaptability to diverse tasks. In contrast, decentralized systems empower individuals with autonomous decision-making, enhancing adaptability and system robustness. Yet, this flexibility comes at the cost of reduced accuracy and efficiency in task execution. In this work, we present a unique method for regulating the centralized dynamic behavior of self-organizing clusters based on environmental interactions. Within this environment-coupled robot system, each robot possesses similar dynamic characteristics, and their internal programs are entirely identical. However, their behaviors can be guided by the centralized control of the environment, facilitating the accomplishment of diverse cluster tasks. This approach aims to balance the accuracy and flexibility of centralized control with the robustness and task adaptability of decentralized control. The proactive regulation of dynamic behavioral characteristics in active matter groups, demonstrated in this work through environmental interactions, holds the potential to introduce a novel technological approach and provide experimental references for studying the dynamic behavior control of large-scale artificial active matter systems.展开更多
In classical matter systems, typical phase-transition phenomena usually stem from changes in state variables, such as temperature and pressure, induced by external regulations such as heat transfer and volume adjustme...In classical matter systems, typical phase-transition phenomena usually stem from changes in state variables, such as temperature and pressure, induced by external regulations such as heat transfer and volume adjustment. However, in active matter systems, the self-propulsion nature of active particles endows the systems with the ability to induce unique collectivestate transitions by spontaneously regulating individual properties to alter the overall states. Based on an innovative robot-swarm experimental system, we demonstrate a field-driven active matter model capable of modulating individual motion behaviors through interaction with a recoverable environmental resource field by the resource perception and consumption.In the simulated model, by gradually reducing the individual resource-conversion coefficient over time, this robotic active matter can spontaneously decrease the overall level of motion, thereby actively achieving a regulation behavior like the cooling-down control. Through simulation calculations, we discover that the spatial structures of this robotic active matter convert from disorder to order during this process, with the resulting ordered structures exhibiting a high self-adaptability on the geometry of the environmental boundaries.展开更多
Aerosol ammonium(NH_(4)^(+)),mainly produced from the reactions of ammonia(NH_(3))with acids in the atmosphere,has significant impacts on air pollution,radiative forcing,and human health.Understanding the source and f...Aerosol ammonium(NH_(4)^(+)),mainly produced from the reactions of ammonia(NH_(3))with acids in the atmosphere,has significant impacts on air pollution,radiative forcing,and human health.Understanding the source and formation mechanism of NH_(4)^(+)can provide scientific insights into air quality improvements.However,the sources of NH_(3)in urban areas are not well understood,and few studies focus on NH_(3)/NH_(4)^(+)at different heights within the atmospheric boundary layer,which hinders a comprehensive understanding of aerosol NH_(4)^(+).In this study,we perform both field observation and modeling studies(the Community Multiscale Air Quality,CMAQ)to investigate regional NH_(3)emission sources and vertically resolved NH_(4)^(+)formation mechanisms during the winter in Beijing.Both stable nitrogen isotope analyses and CMAQ model suggest that combustion-related NH_(3)emissions,including fossil fuel sources,NH_(3)slip,and biomass burning,are important sources of aerosol NH_(4)^(+)with more than 60%contribution occurring on heavily polluted days.In contrast,volatilization-related NH_(3)sources(livestock breeding,N-fertilizer application,and human waste)are dominant on clean days.Combustion-related NH_(3)is mostly local from Beijing,and biomass burning is likely an important NH_(3)source(~15%–20%)that was previously overlooked.More effective control strategies such as the two-product(e.g.,reducing both SO_(2)and NH_(3))control policy should be considered to improve air quality.展开更多
The significant impact of earthquakes on human lives and the built environment underscores the extensive human and economic losses caused by structural collapses. Over the years, researchers have focused on improving ...The significant impact of earthquakes on human lives and the built environment underscores the extensive human and economic losses caused by structural collapses. Over the years, researchers have focused on improving seismic design to mitigate earthquake-induced damages and enhance structural performance. In this study, a specific reinforced concrete (RC) frame structure at Kyungpook National University, designed for educational purposes, is analyzed as a representative case. Utilizing SAP 2000, the research conducts a nonlinear time history analysis to assess the structural performance under seismic conditions. The primary objective is to evaluate the influence of different column section designs, while maintaining identical column section areas, on structural behavior. The study employs two distinct seismic waves from Abeno (ABN) and Takatori (TKT) for the analysis, comparing the structural performance under varying seismic conditions. Key aspects examined include displacement, base shear force, base moment, joint radians, and layer displacement angle. This research is anticipated to serve as a valuable reference for seismic restraint reinforcement work on RC buildings, enriching the methods used for evaluating structures through nonlinear time history analysis based on the synthetic seismic wave approach.展开更多
为了探究郑州城市公园鸟类群落是否符合嵌套分布格局及其影响因素,本研究从中国观鸟记录中心收集了2019–2022年每年3–7月河南省郑州市15个城市公园的鸟类记录数据。使用WNODF(weighted nestedness metric based on overlap and decrea...为了探究郑州城市公园鸟类群落是否符合嵌套分布格局及其影响因素,本研究从中国观鸟记录中心收集了2019–2022年每年3–7月河南省郑州市15个城市公园的鸟类记录数据。使用WNODF(weighted nestedness metric based on overlap and decreasing fill)分别计算郑州城市公园全部鸟类、林鸟和水鸟群落的嵌套分布格局,采用Spearman偏相关检验分析了公园嵌套序列与公园特征参数(公园面积、隔离度、生境类型数量和建筑指数)的关系,以及物种嵌套序列与物种生态学特征(体长、地理分布范围、窝卵数和最小面积需求)的关系。WNODF分析结果显示,郑州城市公园全部鸟类、林鸟和水鸟群落均是显著嵌套的。Spearman偏相关分析结果显示,公园面积和最小面积需求与鸟类群落嵌套程度显著相关,生境地点矩阵分析结果显示为显著嵌套,建筑指数也会影响水鸟群落的嵌套分布格局,但随机放置模型结果显示城市公园鸟类不符合被动取样假说。因此,选择性灭绝与生境嵌套是郑州城市公园全部鸟类、林鸟和水鸟群落嵌套分布格局的主要驱动因素。研究结果表明,为了更好地保护郑州城市公园的鸟类多样性,应优先保护面积较大和生境类型多的公园,以及最小面积需求大的鸟类;同时由于水鸟与林鸟对城市化的反应不同,在制定保护策略时应区别对待。展开更多
动物群落是构成城市绿地生态系统的关键要素,声景作为野生动物重要的生态信息,掌握其时空变化及其影响因素,对于指导城市绿地景观设计与生物多样性保护具有重要意义。本文以Web of Science数据库的核心合集2005–2022年收录的67篇研究...动物群落是构成城市绿地生态系统的关键要素,声景作为野生动物重要的生态信息,掌握其时空变化及其影响因素,对于指导城市绿地景观设计与生物多样性保护具有重要意义。本文以Web of Science数据库的核心合集2005–2022年收录的67篇研究文献为对象,综合梳理与分析了城市绿地动物声景的时空模式及其驱动因素。城市绿地动物声景在空间上表现出环境空间梯度和植被空间结构的差异,动物声音多样性随海拔、纬度、城市化程度的降低以及植被类型和高度的增加呈现升高趋势。时间尺度呈现出昼夜、季节和年度变化差异,表现为鸟类在黎明和黄昏合唱、昆虫和两栖动物在夜间鸣叫以及季节性和年度性发声规律等。影响城市动物声景模式的因素主要包括植被、环境、人为干扰和动物自身驱动等。动物声景作为当前声景生态学研究的热点之一,面临大时空尺度演变规律研究不足、动物声景分析有限等挑战,建议未来着重开展多时空尺度变化规律研究、创新动物声景分析方法、定量解析影响因素及其响应机制、建立全球动物声景数据库等。展开更多
文摘目的对比无机三氧化物聚合物(MTA)、iRoot BP Plus在难治性前牙根尖周病患者根管治疗中的应用效果。方法选取2016年3月—2018年3月承德医学院附属医院口腔科收治的246例难治性前牙根尖周病患者,均为单颗患病且实施根管倒充填治疗。其中82例患者采用MTA治疗(MTA组),84例患者采用iRoot BP Plus治疗(iRoot BP Plus组),80例患者接受氢氧化钙糊剂治疗(对照组)。对比根充质量、治疗前和治疗1周后局部红肿、疼痛评分,不同时刻旧根尖指数(O-PAI)变化及临床疗效。结果iRoot BP Plus组适充率较MTA组和对照组高(P<0.05)。MTA组治疗前和治疗1周后局部红肿、疼痛评分的差值较对照组高(P<0.05),iRoot BP Plus组最高(P<0.05)。iRoot BP Plus组O-PAI评级较MTA组、对照组低(P<0.05),相对效果较好;MTA组治疗后较对照组低(P<0.05),相对效果较好。iRoot BP Plus组临床总有效率最高(P<0.05)。结论在难治性前牙根尖周病患者根管治疗中MTA、iRoot BP Plus均优于氢氧化钙糊剂,且应用iRoot BP Plus可保证适充率,并有效减轻局部红肿、疼痛,改善O-PAI,疗效理想,有望替代MTA推广应用。
基金Project supported by the National Natural Science Foundation of China (Grant No. 12174041)China Postdoctoral Science Foundation (CPSF)(Grant No. 2022M723118)the seed grants from the Wenzhou Institute,University of Chinese Academy of Sciences (Grant No. WIUCASQD2021002)。
文摘How to control the dynamic behavior of large-scale artificial active matter is a critical concern in experimental research on soft matter, particularly regarding the emergence of collective behaviors and the formation of group patterns. Centralized systems excel in precise control over individual behavior within a group, ensuring high accuracy and controllability in task execution. Nevertheless, their sensitivity to group size may limit their adaptability to diverse tasks. In contrast, decentralized systems empower individuals with autonomous decision-making, enhancing adaptability and system robustness. Yet, this flexibility comes at the cost of reduced accuracy and efficiency in task execution. In this work, we present a unique method for regulating the centralized dynamic behavior of self-organizing clusters based on environmental interactions. Within this environment-coupled robot system, each robot possesses similar dynamic characteristics, and their internal programs are entirely identical. However, their behaviors can be guided by the centralized control of the environment, facilitating the accomplishment of diverse cluster tasks. This approach aims to balance the accuracy and flexibility of centralized control with the robustness and task adaptability of decentralized control. The proactive regulation of dynamic behavioral characteristics in active matter groups, demonstrated in this work through environmental interactions, holds the potential to introduce a novel technological approach and provide experimental references for studying the dynamic behavior control of large-scale artificial active matter systems.
基金Project supported by the National Natural Science Foundation of China(Grant No.12174041)China Postdoctoral Science Foundation(Grant No.2022M723118)the Seed Grants from the Wenzhou Institute,University of Chinese Academy of Sciences(Grant No.WIUCASQD2021002)。
文摘In classical matter systems, typical phase-transition phenomena usually stem from changes in state variables, such as temperature and pressure, induced by external regulations such as heat transfer and volume adjustment. However, in active matter systems, the self-propulsion nature of active particles endows the systems with the ability to induce unique collectivestate transitions by spontaneously regulating individual properties to alter the overall states. Based on an innovative robot-swarm experimental system, we demonstrate a field-driven active matter model capable of modulating individual motion behaviors through interaction with a recoverable environmental resource field by the resource perception and consumption.In the simulated model, by gradually reducing the individual resource-conversion coefficient over time, this robotic active matter can spontaneously decrease the overall level of motion, thereby actively achieving a regulation behavior like the cooling-down control. Through simulation calculations, we discover that the spatial structures of this robotic active matter convert from disorder to order during this process, with the resulting ordered structures exhibiting a high self-adaptability on the geometry of the environmental boundaries.
基金supported by the National Natural Science Foundation of China(42130513,41905110,and 41961130384)the Royal Society Newton Advanced Fellowship,United Kingdom(NAFR1191220)the Research Grants Council of the Hong Kong Special Administrative Region,China(T24/504/17 and A-Poly U502/16)。
文摘Aerosol ammonium(NH_(4)^(+)),mainly produced from the reactions of ammonia(NH_(3))with acids in the atmosphere,has significant impacts on air pollution,radiative forcing,and human health.Understanding the source and formation mechanism of NH_(4)^(+)can provide scientific insights into air quality improvements.However,the sources of NH_(3)in urban areas are not well understood,and few studies focus on NH_(3)/NH_(4)^(+)at different heights within the atmospheric boundary layer,which hinders a comprehensive understanding of aerosol NH_(4)^(+).In this study,we perform both field observation and modeling studies(the Community Multiscale Air Quality,CMAQ)to investigate regional NH_(3)emission sources and vertically resolved NH_(4)^(+)formation mechanisms during the winter in Beijing.Both stable nitrogen isotope analyses and CMAQ model suggest that combustion-related NH_(3)emissions,including fossil fuel sources,NH_(3)slip,and biomass burning,are important sources of aerosol NH_(4)^(+)with more than 60%contribution occurring on heavily polluted days.In contrast,volatilization-related NH_(3)sources(livestock breeding,N-fertilizer application,and human waste)are dominant on clean days.Combustion-related NH_(3)is mostly local from Beijing,and biomass burning is likely an important NH_(3)source(~15%–20%)that was previously overlooked.More effective control strategies such as the two-product(e.g.,reducing both SO_(2)and NH_(3))control policy should be considered to improve air quality.
文摘The significant impact of earthquakes on human lives and the built environment underscores the extensive human and economic losses caused by structural collapses. Over the years, researchers have focused on improving seismic design to mitigate earthquake-induced damages and enhance structural performance. In this study, a specific reinforced concrete (RC) frame structure at Kyungpook National University, designed for educational purposes, is analyzed as a representative case. Utilizing SAP 2000, the research conducts a nonlinear time history analysis to assess the structural performance under seismic conditions. The primary objective is to evaluate the influence of different column section designs, while maintaining identical column section areas, on structural behavior. The study employs two distinct seismic waves from Abeno (ABN) and Takatori (TKT) for the analysis, comparing the structural performance under varying seismic conditions. Key aspects examined include displacement, base shear force, base moment, joint radians, and layer displacement angle. This research is anticipated to serve as a valuable reference for seismic restraint reinforcement work on RC buildings, enriching the methods used for evaluating structures through nonlinear time history analysis based on the synthetic seismic wave approach.
文摘为了探究郑州城市公园鸟类群落是否符合嵌套分布格局及其影响因素,本研究从中国观鸟记录中心收集了2019–2022年每年3–7月河南省郑州市15个城市公园的鸟类记录数据。使用WNODF(weighted nestedness metric based on overlap and decreasing fill)分别计算郑州城市公园全部鸟类、林鸟和水鸟群落的嵌套分布格局,采用Spearman偏相关检验分析了公园嵌套序列与公园特征参数(公园面积、隔离度、生境类型数量和建筑指数)的关系,以及物种嵌套序列与物种生态学特征(体长、地理分布范围、窝卵数和最小面积需求)的关系。WNODF分析结果显示,郑州城市公园全部鸟类、林鸟和水鸟群落均是显著嵌套的。Spearman偏相关分析结果显示,公园面积和最小面积需求与鸟类群落嵌套程度显著相关,生境地点矩阵分析结果显示为显著嵌套,建筑指数也会影响水鸟群落的嵌套分布格局,但随机放置模型结果显示城市公园鸟类不符合被动取样假说。因此,选择性灭绝与生境嵌套是郑州城市公园全部鸟类、林鸟和水鸟群落嵌套分布格局的主要驱动因素。研究结果表明,为了更好地保护郑州城市公园的鸟类多样性,应优先保护面积较大和生境类型多的公园,以及最小面积需求大的鸟类;同时由于水鸟与林鸟对城市化的反应不同,在制定保护策略时应区别对待。
文摘动物群落是构成城市绿地生态系统的关键要素,声景作为野生动物重要的生态信息,掌握其时空变化及其影响因素,对于指导城市绿地景观设计与生物多样性保护具有重要意义。本文以Web of Science数据库的核心合集2005–2022年收录的67篇研究文献为对象,综合梳理与分析了城市绿地动物声景的时空模式及其驱动因素。城市绿地动物声景在空间上表现出环境空间梯度和植被空间结构的差异,动物声音多样性随海拔、纬度、城市化程度的降低以及植被类型和高度的增加呈现升高趋势。时间尺度呈现出昼夜、季节和年度变化差异,表现为鸟类在黎明和黄昏合唱、昆虫和两栖动物在夜间鸣叫以及季节性和年度性发声规律等。影响城市动物声景模式的因素主要包括植被、环境、人为干扰和动物自身驱动等。动物声景作为当前声景生态学研究的热点之一,面临大时空尺度演变规律研究不足、动物声景分析有限等挑战,建议未来着重开展多时空尺度变化规律研究、创新动物声景分析方法、定量解析影响因素及其响应机制、建立全球动物声景数据库等。
