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The clutch size,incubation behavior of Reeves’s Pheasant(Syrmaticus reevesii) and their responses to ambient temperature and precipitation
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作者 Ting Jin Shuai Lu +7 位作者 Yunqi Wang Junqin Hua Zhengxiao Liu Qian Hu Yating Liu Yuze Zhao Jianqiang Li Jiliang Xu 《Avian Research》 SCIE CSCD 2024年第1期72-80,共9页
Weather conditions play a pivotal role in embryo development and parental incubation costs,potentially impacting the clutch size and incubation behavior of birds.Understanding these effects is crucial for bird conserv... Weather conditions play a pivotal role in embryo development and parental incubation costs,potentially impacting the clutch size and incubation behavior of birds.Understanding these effects is crucial for bird conservation.Reeves’ s Pheasant(Syrmaticus reevesii) is a threatened species endemic to China,which is characterized by female-only incubation.However,there is a lack of information regarding the impact of weather conditions on clutch size and incubation behavior in this species.Using satellite tracking,we tracked 27 wild female Reeves’ s Pheasants from 2020 to 2023 in Hubei Province,China.We explored their clutch size and incubation behavior,as well as their responses to ambient temperature and precipitation.Clutch size averaged 7.75 ±1.36,had an association with average ambient temperature and average daily precipitation during the egglaying period,and was potentially linked to female breeding attempts.Throughout the incubation period,females took an average of 0.73 ±0.46 recesses every 24 h,with an average recess duration of 100.80 ±73.37 min and an average nest attendance of 92.98 ±5.27%.They showed a unimodal recess pattern in which nest departures peaked primarily between 13:00 and 16:00.Furthermore,females rarely left nests when daily precipitation was high.Recess duration and nest attendance were influenced by the interaction between daily mean ambient temperature and daily precipitation,as well as day of incubation.Additionally,there was a positive correlation between clutch size and recess duration.These results contribute valuable insights into the lifehistory features of this endangered species. 展开更多
关键词 Ambient temperature Clutch size Incubation behavior PRECIPITATION Reevess Pheasant
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Interconnected microstructure and flexural behavior of Ti_(2)C-Ti composites with superior Young’s modulus
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作者 Fengbo Sun Rui Zhang +3 位作者 Fanchao Meng Shuai Wang Lujun Huang Lin Geng 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2024年第9期2088-2101,共14页
To enhance the Young’s modulus(E)and strength of titanium alloys,we designed titanium matrix composites with intercon-nected microstructure based on the Hashin-Shtrikman theory.According to the results,the in-situ re... To enhance the Young’s modulus(E)and strength of titanium alloys,we designed titanium matrix composites with intercon-nected microstructure based on the Hashin-Shtrikman theory.According to the results,the in-situ reaction yielded an interconnected microstructure composed of Ti_(2)C particles when the Ti_(2)C content reached 50vol%.With widths of 10 and 230 nm,the intraparticle Ti lamellae in the prepared composite exhibited a bimodal size distribution due to precipitation and the unreacted Ti phase within the grown Ti_(2)C particles.The composites with interconnected microstructure attained superior properties,including E of 174.3 GPa and ultimate flexural strength of 1014 GPa.Compared with that of pure Ti,the E of the composite was increased by 55% due to the high Ti_(2)C content and interconnected microstructure.The outstanding strength resulted from the strong interfacial bonding,load-bearing capacity of interconnected Ti_(2)C particles,and bimodal intraparticle Ti lamellae,which minimized the average crack driving force.Interrupted flexural tests revealed preferential crack initiation along the{001}cleavage plane and grain boundary of Ti_(2)C in the region with the highest tensile stress.In addition,the propagation can be efficiently inhibited by interparticle Ti grains,which prevented the brittle fracture of the composites. 展开更多
关键词 titanium matrix composites titanium carbide INTERFACE Young’s modulus flexural behavior
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Research on the Influence of Family Education on Children’s Behavioral Habits
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作者 Jiayi Wen 《Journal of Contemporary Educational Research》 2024年第8期176-180,共5页
Under the background of the all-round deepening of quality education,the cultivation of comprehensive quality has become the main theme of contemporary education reform.Good behavior and habits are of great significan... Under the background of the all-round deepening of quality education,the cultivation of comprehensive quality has become the main theme of contemporary education reform.Good behavior and habits are of great significance to children’s future learning,growth,and development.Through literature review and other methods,this paper analyzes the current situation of children’s family education and the influence of family education on the cultivation of children’s behavioral habits and provides some strategies for cultivating children’s good behavioral habits in family education. 展开更多
关键词 Family education Children’s behavior Habit cultivation PARENTs
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GREEN'S FUNCTION AND THE POINTWISE BEHAVIORS OF THE VLASOV-POISSON-FOKKER-PLANCK SYSTEM
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作者 钟明溁 《Acta Mathematica Scientia》 SCIE CSCD 2023年第1期205-236,共32页
The pointwise space-time behaviors of the Green’s function and the global solution to the Vlasov-Poisson-Fokker-Planck(VPFP)system in three dimensional space are studied in this paper.It is shown that the Green’s fu... The pointwise space-time behaviors of the Green’s function and the global solution to the Vlasov-Poisson-Fokker-Planck(VPFP)system in three dimensional space are studied in this paper.It is shown that the Green’s function consists of the diffusion waves decaying exponentially in time but algebraically in space,and the singular kinetic waves which become smooth for all(t,x,v)when t>0.Furthermore,we establish the pointwise space-time behaviors of the global solution to the nonlinear VPFP system when the initial data is not necessarily smooth in terms of the Green’s function. 展开更多
关键词 Vlasov-Poisson-Fokker-Planck system Green’s function pointwise behavior spectrum structure
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改进YOLOv7-tiny与D-S理论结合的实验室人员行为检测研究
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作者 杨永亮 曹敏 +4 位作者 徐凌桦 王霄 杨靖 王涛 冯平平 《现代电子技术》 北大核心 2024年第19期153-160,共8页
针对目前实验室场景缺少对人员行为检测的方法,且主流算法精度低、误检率高的问题,文中提出一种改进YOLOv7-tiny的人员行为检测算法,并通过多源信息融合,提高人员行为在实际实验室场景中的识别准确率。首先,在检测算法主干网络引入Ghost... 针对目前实验室场景缺少对人员行为检测的方法,且主流算法精度低、误检率高的问题,文中提出一种改进YOLOv7-tiny的人员行为检测算法,并通过多源信息融合,提高人员行为在实际实验室场景中的识别准确率。首先,在检测算法主干网络引入GhostNetV2轻量化网络,进一步降低模型计算量和复杂度;其次,在颈部网络嵌入改进后的CBAM_E注意力模块,加强目标重要特征的提取;再次,在预测端使用SIoU替换原有的损失函数,减少角度因素和边界框回归精度的影响。检测结果表明,相较于YOLOv7-tiny,文中算法精度提升10.08%,模型参数量和复杂度分别下降36.45%和46.76%。最后通过将检测数据与传感器采集数据运用D-S证据理论进行信息融合后发现,人员不规范行为检测的误检率得到有效降低。结果表明,该方法可实现对实验室人员不规范行为的有效检测。 展开更多
关键词 实验室场景 人员行为 YOLOv7-tiny 轻量化网络 注意力模块 损失函数 D-s证据理论 信息融合
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热处理对电沉积Ni-S合金微观组织和析氢性能的影响
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作者 严欣昱 龙飞 +4 位作者 李轩 孙菲 杨纪帆 周潼 刘磊 《电镀与精饰》 CAS 北大核心 2024年第7期8-14,共7页
电解水制氢是目前最有望替代矿石燃料制氢的技术,低成本且高效的析氢电极是限制电解水制氢大规模应用的瓶颈问题,而Ni-S合金具有易制备和高活性等优点,作为电解水的阴极材料具有极大的潜力。通过电沉积法在泡沫镍表面制备了非晶Ni-S合金... 电解水制氢是目前最有望替代矿石燃料制氢的技术,低成本且高效的析氢电极是限制电解水制氢大规模应用的瓶颈问题,而Ni-S合金具有易制备和高活性等优点,作为电解水的阴极材料具有极大的潜力。通过电沉积法在泡沫镍表面制备了非晶Ni-S合金,研究了Ni-S合金的晶化行为对其析氢性能的影响,热处理促使非晶Ni-S合金镀层再结晶转变为以Ni_(3)S_(2)和Ni为主的结晶层,电化学分析结果表明热处理减少非晶Ni-S合金镀层的析氢活性位点,增大氢气从Ni-S合金表面脱附难度,显著削弱Ni-S/NF电极的电化学析氢性能。 展开更多
关键词 电沉积 Ni-s合金 热处理 晶化行为 电催化
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SAMP8小鼠在中医药抗痴呆中的应用研究进展
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作者 吴国庆 高誉珊 +1 位作者 汪子栋 李志刚 《世界科学技术-中医药现代化》 CSCD 北大核心 2024年第4期886-894,共9页
快速老化小鼠是一种早期学习记忆障碍模型,因其表现出阿尔茨海默病发病机制的大多数特征,包括抗衰老因子的异常表达、炎症因子的过度升高、淀粉样蛋白沉积、tau蛋白过度磷酸化、线粒体自噬、血脑屏障损伤的中枢机制以及多系统多器官的... 快速老化小鼠是一种早期学习记忆障碍模型,因其表现出阿尔茨海默病发病机制的大多数特征,包括抗衰老因子的异常表达、炎症因子的过度升高、淀粉样蛋白沉积、tau蛋白过度磷酸化、线粒体自噬、血脑屏障损伤的中枢机制以及多系统多器官的病理损伤,因而成为阿尔茨海默病(Alzheimer's disease,AD)研究的理想模型而广泛应用。随着AD机制实验研究的不断深入,发现SAMP8小鼠在行为活动、组织病理及生化参数指标上相较于SAMR1发生明显变化,并与人体疾病相类似。基于此,本文对SAMP8小鼠的行为学、组织病理和中医药实验研究进行了系统综述,加深对SAMP8小鼠的认识,了解其生理病理特性,并依据中医药实验研究对其中医证型进行推测,以期对SAMP8小鼠的科学应用提供有益帮助。 展开更多
关键词 快速老化小鼠 行为学 病理变化 阿尔茨海默病 综述
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基于人脸识别的课堂教学行为S-T分析系统设计
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作者 韦雁仙 李霖 段宁贵 《梧州学院学报》 2024年第3期36-45,共10页
提出并详细介绍了一种基于人脸识别技术的课堂教学行为S-T分析系统的设计。该系统以S-T分析法为理论基础,采用多种人脸识别算法,包括年龄检测、表情分析、姿态分析等,旨在自动识别并分析教师和学生在课堂上的行为。基于大量课堂视频数... 提出并详细介绍了一种基于人脸识别技术的课堂教学行为S-T分析系统的设计。该系统以S-T分析法为理论基础,采用多种人脸识别算法,包括年龄检测、表情分析、姿态分析等,旨在自动识别并分析教师和学生在课堂上的行为。基于大量课堂视频数据的准备、软件系统原型的设计、深入研究课堂教学行为理论等,解决人脸识别技术的算法选型、视频关键帧的分析与因果关系模型的建立、系统运行的稳定性和界面设计等关键技术问题。通过系统性的需求分析、设计与架构、实现、评估与可视化等阶段的论述,详细展现了该系统的开发过程。 展开更多
关键词 课堂教学行为 s-T分析法 人脸识别技术 关键帧
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Feasibility Study of Neurofeedback Therapy for Alzheimer’s Disease
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作者 Ruyu Li Min Yang 《Advances in Alzheimer's Disease》 CAS 2024年第3期49-64,共16页
Objective: This study aims to evaluate the feasibility and effectiveness of neurofeedback therapy based on brain-computer interface (BCI) games in enhancing cognitive functions and reducing disruptive behaviors in pat... Objective: This study aims to evaluate the feasibility and effectiveness of neurofeedback therapy based on brain-computer interface (BCI) games in enhancing cognitive functions and reducing disruptive behaviors in patients with Alzheimer’s disease (AD). Methods: Forty-six AD patients aged 49 - 76 years were recruited for the study. Neurofeedback regulation was conducted using a BCI game designed to modulate EEG rhythms. Cognitive function was assessed using MMSE, MoCA, and ADAS-cog scales before and after a 10-day training period. EEG measurements were taken to evaluate changes in brain activity complexity. Statistical analyses were performed using SPSS25.0 software to compare pre- and post-training scores. Results: Post-intervention results showed significant improvement in the cognitive function of AD patients. The total scores of MMSE, MoCA, and ADAS-cog scales increased significantly (P < 0.01). Notable improvements were observed in memory, language, and attention domains. EEG complexity in the left frontal area also showed a significant increase (P < 0.05). Additionally, the disruptive behaviors of patients were significantly reduced, improving their overall quality of life. Conclusions: Neurofeedback therapy based on BCI games is a promising intervention for enhancing cognitive functions and reducing disruptive behaviors in AD patients. This innovative approach demonstrates significant potential for clinical application, providing a non-invasive method to improve patient outcomes. Further studies with larger sample sizes and long-term follow-ups are recommended to validate these findings and explore the specific effects of NFB training on different cognitive impairment levels. 展开更多
关键词 Alzheimer’s Disease Brain-Computer Interface NEUROFEEDBACK Cognitive Function Disruptive behaviors
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SnAgCu-Al_(2)O_(3)在不同织构角度下对TiNi润滑行为的影响
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作者 熊亚辉 林海波 +1 位作者 熊邦英 杨慷 《表面技术》 EI CAS CSCD 北大核心 2024年第17期103-111,共9页
目的研究高镍钛基合金(TiNi)的摩擦学性能以提高其使用精度和服役寿命。方法以TiNi为研究对象,结合仿生学方法在TiNi表面设计并制备了鱼鳞状表面织构。随后将复合固体润滑剂Sn AgCu-Al_(2)O_(3)(S-A)均匀填充至织构,使用摩擦磨损测试仪... 目的研究高镍钛基合金(TiNi)的摩擦学性能以提高其使用精度和服役寿命。方法以TiNi为研究对象,结合仿生学方法在TiNi表面设计并制备了鱼鳞状表面织构。随后将复合固体润滑剂Sn AgCu-Al_(2)O_(3)(S-A)均匀填充至织构,使用摩擦磨损测试仪对制备的样品进行摩擦实验。最后利用场发射扫描电子显微镜和三维表面形貌仪对磨痕表面进行表征,重点分析表面织构的角度参数对复合材料Sn Ag Cu-Al_(2)O_(3)/TiNi(S-A/TiNi)摩擦学性能的影响。结果与TiNi相比,当表面织构的角度为70°时,S-A/TiNi-70°的平均摩擦因数和磨损率分别降低约81.8%和85.5%,其值分别约为0.1和1.2×10^(-13)m^(3)/(N·m)。结论研究过程中发现,S-A/TiNi-70°试样表现的优异摩擦学性能依赖于S-A固体润滑膜的完整性,摩擦表面形成的固体润滑膜越连续其表面磨损越小。S-A/TiNi-70°试样优异的摩擦学性能主要归因于在表面织构角度为70°时,织构凹槽中的S-A固体润滑剂相较于其他角度更容易流动。这导致织构凹槽中的润滑剂能够大量迁移到摩擦表面形成S-A固体润滑膜,从而减少了摩擦副和基体直接接触。 展开更多
关键词 s-A/TiNi 摩擦学性能 表面织构 润滑行为 固体润滑剂
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An Explanation of the Temperature-Dependent Upper Critical Field Data of H3S on the Basis of the Thermodynamics of a Superconductor in a Magnetic Field
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作者 Gulshan Prakash Malik 《World Journal of Condensed Matter Physics》 CAS 2024年第3期45-50,共6页
Excellent fits to a couple of the data-sets on the temperature (T)-dependent upper critical field (Hc2) of H3S (critical temperature, Tc ≈ 200 K at pressure ≈ 150 GPa) reported by Mozaffari, et al. (2019) were obtai... Excellent fits to a couple of the data-sets on the temperature (T)-dependent upper critical field (Hc2) of H3S (critical temperature, Tc ≈ 200 K at pressure ≈ 150 GPa) reported by Mozaffari, et al. (2019) were obtained by Talantsev (2019) in an approach based on an ingenious mix of the Ginzberg-Landau (GL), the Werthamer, Helfand and Hohenberg (WHH), and the Gor’kov, etc., theories which have individually been employed for the same purpose for a long time. Up to the lowest temperature (TL) in each of these data-sets, similarly accurate fits have also been obtained by Malik and Varma (2023) in a radically different approach based on the Bethe-Salpeter equation (BSE) supplemented by the Matsubara and the Landau quantization prescriptions. For T TL, however, while the (GL, WHH, etc.)-based approach leads to Hc2(0) ≈ 100 T, the BSE-based approach leads to about twice this value even at 1 K. In this paper, a fit to one of the said data-sets is obtained for the first time via a thermodynamic approach which, up to TL, is as good as those obtained via the earlier approaches. While this is interesting per se, another significant result of this paper is that for T TL it corroborates the result of the BSE-based approach. 展开更多
关键词 H3s Upper Critical Field (Hc2) Variation of Hc2 with Temperature Clausius-Clapeyron equation in a magnetic field behavior of Hc2 for Temperatures Close to 0 K
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消费者使用绿色快递包装的意愿研究:基于S-O-R框架的综合分析
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作者 许明星 简庆 +2 位作者 俞若姗 曾金盾 陈鑫怡 《河南工业大学学报(社会科学版)》 2024年第3期49-59,共11页
消费者受到内外部刺激之后会影响其对绿色快递包装的使用意愿。选取S-O-R模型为主要框架,整合TPB(计划行为理论)模型和顾客满意度模型的关键变量,探讨了绿色快递包装相关的内外部刺激对消费者内部状态的影响。采用结构方程模型对在线调... 消费者受到内外部刺激之后会影响其对绿色快递包装的使用意愿。选取S-O-R模型为主要框架,整合TPB(计划行为理论)模型和顾客满意度模型的关键变量,探讨了绿色快递包装相关的内外部刺激对消费者内部状态的影响。采用结构方程模型对在线调查问卷进行了实证检验分析。研究结果表明:消费者使用绿色快递包装的意愿受到态度和知觉行为控制的显著正向影响;内部刺激(感知价值和感知质量)和外部刺激(主观规范、媒体宣传和便利性)正向影响消费者使用绿色快递包装的态度和知觉行为控制。要提高消费者对绿色快递包装的使用意愿,需要加大对绿色快递包装的宣传力度,引导消费者形成积极的态度,强化绿色快递包装的实用功能,增强消费者行为控制信心。 展开更多
关键词 绿色快递包装 s-O-R模型 行为意图 使用意愿
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S-O-R理论框架下传统村落品牌“商品化”路径探析——以张谷英村为例 被引量:1
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作者 刘沛林 李境阳 +1 位作者 邓运员 刘瑞瑞 《长沙大学学报》 2023年第3期43-51,共9页
打造传统村落地方品牌并将其转化为实际效益,是实现乡村旅游活化的有效途径。基于S-O-R理论,构建研究理论框架,以湖南岳阳张谷英村为例,运用结构方程模型进行定量实证分析,结果表明:传统村落品牌“商品化”进程涵盖了品牌价值提升、文... 打造传统村落地方品牌并将其转化为实际效益,是实现乡村旅游活化的有效途径。基于S-O-R理论,构建研究理论框架,以湖南岳阳张谷英村为例,运用结构方程模型进行定量实证分析,结果表明:传统村落品牌“商品化”进程涵盖了品牌价值提升、文化价值延伸、经济效益转化三部分;传统村落地方品牌建构对游客消费行为起间接影响作用,地方依恋是沟通地方品牌建构与游客消费行为的“桥梁”,其中介效应得到了验证;为实现地方品牌价值向经济效益的有效转化,应当深度挖掘传统村落文化内涵,注重保护乡土景观,完善食宿消费服务体系,使单一产业转向多产业模式发展。 展开更多
关键词 传统村落 s-O-R理论 地方品牌建构 游客消费行为
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PLA/PBS/PEG共混体系非等温热分解动力学 被引量:1
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作者 付蕾 田婕 郑斌 《塑料工业》 CAS CSCD 北大核心 2023年第6期92-98,共7页
为了探究聚乳酸/聚丁二酸丁二醇酯/聚乙二醇(PLA/PBS/PEG)共混体系的热分解行为,通过熔融开炼共混法制备了PLA/PBS/PEG共混体系,利用同步热分析仪考察了不同加热速率下复合材料的热解行为。使用无模型方法Kissinger方程和Ozawa方程计算... 为了探究聚乳酸/聚丁二酸丁二醇酯/聚乙二醇(PLA/PBS/PEG)共混体系的热分解行为,通过熔融开炼共混法制备了PLA/PBS/PEG共混体系,利用同步热分析仪考察了不同加热速率下复合材料的热解行为。使用无模型方法Kissinger方程和Ozawa方程计算出了平均活化能,运用模型方法Coats-Redfern方程,将不同的热解机理函数带入其中,计算出活化能,将两个活化能进行对比,以明确最合适的反应模型。结果表明,该复合材料的热解机理函数为G(α)=[1-(1-α)^(-3)]/(-3),即随机成核随后生长。 展开更多
关键词 聚乳酸/聚丁二酸丁二醇酯/聚乙二醇 热解行为 Kissinger方程 Ozawa方程
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Effects of UV-B radiation on fitness related behaviors of the sea urchin Strongylocentrotus intermedius 被引量:3
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作者 SHI Dongtao DING Jingyun +4 位作者 ZHANG Lingling ZHANG Lisheng SUN Jiangnan CHANGYaqing ZHAO Chong 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2018年第5期1681-1687,共7页
Ozone depletion induced by anthropogenic gases has been increasing the transmission of solar ultraviolet-B radiation(UV-B, 280–315 nm) through the atmosphere, which may impact the fitness of marine invertebrates in i... Ozone depletion induced by anthropogenic gases has been increasing the transmission of solar ultraviolet-B radiation(UV-B, 280–315 nm) through the atmosphere, which may impact the fitness of marine invertebrates in intertidal and shallow waters. To our knowledge, however, the responses of fitness related behaviors to UV-B radiation at different intensities have been rarely studied in marine invertebrates. For the first time, the present study investigated the eff ects of exposure of one hour to UV-B radiation at different intensities on foraging behavior, Aristotle's lantern reflex and righting behavior of the sea urchin Strongylocentrotus intermedius. Exposure of one hour to UV-B radiation at 10 μW/cm^2 significantly reduced foraging behavior. An intensity dependent eff ect of exposure to UV-B radiation was found in the duration of the Aristotle's lantern reflex. Exposure to UV-B radiation at 20 μW/cm^2 for one hour significantly reduced the duration of the Aristotle's lantern reflex, but 10 μW/cm^2 did not. There was no significant diff erence of righting response time among sea urchins exposed to 0, 10 and 20 μW/cm^2 for one hour. To test potential carryover ef fects, the behavioral traits were re-measured three days later. We found significant carryover eff ects of UV-B radiation on foraging time and righting response time, but not on the duration of the Aristotle's lantern reflex. The present study indicates that a brief exposure of one hour to UV-B radiation can significantly aff ect the duration of Aristotle's lantern reflex, righting response time and foraging behavior of a sea urchin, although the immediate impacts and carryover eff ects were highly trait dependent. This study provides new information into the behavioral responses of marine invertebrates to exposure to UV-B radiation. Future studies should be carried out to investigate long-term carryover eff ects of UV-B radiation on behavioral and physiological fitness related traits. 展开更多
关键词 sea urchin UV-B foraging behavior righting behavior Aristotle's lantern reflex FITNEss
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Corrosion Behavior of the S136 Mold Steel Fabricated by Selective Laser Melting 被引量:6
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作者 Shi-Feng Wen Xian-Tai Ji +3 位作者 Yan Zhou Chang-Jun Han Qing-Song Wei Yu-Sheng Shi 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2018年第6期68-78,共11页
The selective laser melting(SLM) method has a great potential for fabricating injection mold with complex structure. However, the microstructure and performance of the SLM molds show significantly di erent from those ... The selective laser melting(SLM) method has a great potential for fabricating injection mold with complex structure. However, the microstructure and performance of the SLM molds show significantly di erent from those manufac?tured by traditional technologies. In this study, the microstructure, hardness and especially corrosion behavior of the samples fabricated by SLM and casting were investigated. The XRD results exhibit that the γ?Fe phase is only obtained in the SLM parts, and the α?Fe peak slightly moves to low di raction angle compared with casting counterparts. Due to the rapid cooling rate, the SLM samples have fine cellular microstructures while the casting ones have coarse grains with obvious elements segregation. Besides, the SLM samples show anisotropy, hardness of side view and top view are 48.73 and 50.31 HRC respectively, which are 20% higher than that of casting ones. Corrosion results show that the SLM samples have the better anti?corrosion resistance(in a 6% FeCl3 solution for 48 h) but the deeper corrosion pits than casting ones. Finally, the performance of the SLM molds could meet the requirement of injecting production. Moreover, the molds especially present a significant decrease(20%) of cooling time and increases of cooling uniform?ity due to the customized conformal cooling channels. 展开更多
关键词 selective laser melting s136 mold steel Corrosion behavior Conformal?cooling channels
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Combined acupuncture and HuangDiSan treatment affects behavior and synaptophysin levels in the hippocampus of senescence-accelerated mouse prone 8 after neural stem cell transplantation 被引量:8
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作者 Chun-lei Zhou Lan Zhao +6 位作者 Hui-yan Shi Jian-wei Liu liang-wei Shi Bo-hong Kan Zhen Li lian-chun Yu Jing-xian Han 《Neural Regeneration Research》 SCIE CAS CSCD 2018年第3期541-548,共8页
Sanjiao acupuncture and HuangDiSan can promote the proliferation, migration and differentiation of exogenous neural stem cells in senescence-accelerated mouse prone 8 (SAMP8) mice and can improve learning and memory... Sanjiao acupuncture and HuangDiSan can promote the proliferation, migration and differentiation of exogenous neural stem cells in senescence-accelerated mouse prone 8 (SAMP8) mice and can improve learning and memory impairment and behavioral function in dementia-model mice. Thus, we sought to determine whether Sanjiao acupuncture and HuangDiSan can elevate the effect of neural stem cell transplantation in Alzheimer’s disease model mice. Sanjiao acupuncture was used to stimulate Danzhong (CV17), Zhongwan (CV12),Qihai (CV6), bilateral Xuehai (SP10) and bilateral Zusanli (ST36) 15 days before and after implantation of neural stem cells (5 × 10^5) into the hippocampal dentate gyrus of SAMP8 mice. Simultaneously, 0.2 mL HuangDiSan, containing Rehmannia Root and Chinese Angelica,was intragastrically administered. Our results demonstrated that compared with mice undergoing neural stem cell transplantation alone,learning ability was significantly improved and synaptophysin mRNA and protein levels were greatly increased in the hippocampus of mice undergoing both Sanjiao acupuncture and intragastric administration of HuangDiSan. We conclude that the combination of Sanjiao acupuncture and HuangDiSan can effectively improve dementia symptoms in mice, and the mechanism of this action might be related to the regulation of synaptophysin expression. 展开更多
关键词 nerve regeneration neurons NEURODEGENERATION Alzheimer's disease MICROENVIRONMENT Chinese medicine behavior neural stem cell transplantation sYNAPTOPHYsIN neural regeneration
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Effects of trace Ca/Sn addition on corrosion behaviors of biodegradable Mg-4Zn-0.2Mn alloy 被引量:4
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作者 Wenbo Du Ke Liu +2 位作者 Ke Ma Zhaohui Wang Shubo Li 《Journal of Magnesium and Alloys》 SCIE EI CAS 2018年第1期1-14,共14页
The effects of alloying elements of Ca/Sn on corrosion behaviors of the as-cast Mg-4Zn-0.2Mn alloy were investigated by immersion tests and electrochemical methods.The results indicated that the average corrosion rate... The effects of alloying elements of Ca/Sn on corrosion behaviors of the as-cast Mg-4Zn-0.2Mn alloy were investigated by immersion tests and electrochemical methods.The results indicated that the average corrosion rate value of the Mg-4Zn-0.2Mn-Ca alloy was∼0.31 mm/year in Hank’s physiological solution for 40 days,and corrosion resistance increased for the specimens containing Ca element rather than that containing Sn because of the higher breakdown potential value,lower current density and deactivated corrosion rate,which was ascribed to a formation of the uniformly distributed Mg-Zn-Ca ternary phase. 展开更多
关键词 Mg-Zn-Mn alloy Corrosion behaviors Hank’s physiological solution Electrochemical test
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Influence of heat treatment on microstructure and electrochemical behaviors of Mg-Zn binary alloys prepared by gas-phase alloying technique 被引量:2
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作者 MA Jun NIU Li-bin +2 位作者 YAN Yu-ting GAO Chong WANG Xiao-gang 《Journal of Central South University》 SCIE EI CAS CSCD 2020年第3期762-771,共10页
Mg-Zn binary alloys fabricated by the gas-phase alloying technique under vacuum condition were investigated in the state of initial state and after heat treatment for the microstructure and electrochemical behaviors.D... Mg-Zn binary alloys fabricated by the gas-phase alloying technique under vacuum condition were investigated in the state of initial state and after heat treatment for the microstructure and electrochemical behaviors.Different from the traditional Mg-Zn alloys preparation methods,alloys prepared by gas-phase alloying have a large number of intermetallic compounds,such as MgZn,Mg7Zn3 and MgZn2.After solution treatment,the boundary of the eutectic disappeared and the size ofα-Mg increased from 100μm to 150μm.At the same time,the value of the resistance of charge transfer increased,which indicates that the resistance of the charge transfer and the corrosion resistance of the alloys increased.After artificial aging treatment,the distribution ofα-Mg was more uniform and its size was reduced to about 50μm,and there was new eutectic structure formed.The newly formed eutectic structure forms galvanic cells with the alloy matrix,which makes the corrosion resistance of the alloy weaken. 展开更多
关键词 gas-phase alloying Mg-Zn alloy heat treatment Ringer’s solution electrochemical behavior
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Role of P,S and B on Creep Behavior of Alloy 718 被引量:3
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作者 Zhuangqi HU, Hongwei SONG, Shouren GUO and Wenru SUN Institute of Metal Research, The Chinese Academy of Sciences, Shenyang 110016, China 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2001年第4期399-402,共4页
The doping of phosphorus, sulfur and boron in IN718 superalloy can remarkably influence the creep behavior. The modifications of the minor elements seem not to vary the stress exponent and the influences primarily con... The doping of phosphorus, sulfur and boron in IN718 superalloy can remarkably influence the creep behavior. The modifications of the minor elements seem not to vary the stress exponent and the influences primarily concentrate on the effective diffusion coefficient. A pronounced beneficial interaction between P and B and a weaker detrimental interaction between P and S have been obtained. The preexponential frequency constant is proved to be strongly related with the creep activation energy because of the so-called compensation effect. The compensation temperature has been determined to be about 1080 K, which corresponds to the transformation temperature from rapidly coarsened γ'' phase to δ phase. It has been proposed that trace elements can influence the effective diffusion coefficient individually or cooperatively, which in turn either retard or speed the creep process. 展开更多
关键词 Role of P s and B on Creep behavior of Alloy 718
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