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Simulation of Learners’ Behaviors Based on the Modified Cellular Automata Model
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作者 Zhenyan Liang Haiyan Liu +1 位作者 Chaoying Zhang Shangyuan Yang 《Intelligent Information Management》 2010年第9期563-568,共6页
This study develops a computational model for simulation of behaviors of learners under the influence of motivation and engagement environment based on Cellular Automata (CA). It investigates the changing patterns of ... This study develops a computational model for simulation of behaviors of learners under the influence of motivation and engagement environment based on Cellular Automata (CA). It investigates the changing patterns of learners’ behaviors when motivation and engagement environment are assigned with different values respectively. The simulation process indicates that the internal factor, which is the motivation in this paper, plays a key role in changing learners’ behaviors under certain circumstance and the engagement environment also significantly influences learner’s perception. The results obtained also show good agreement with the phenomenon generally being observed in practice. 展开更多
关键词 Motivation ENGAGEMENT Cellular AUTOMATA sIMULATION learner behaviors
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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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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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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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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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GREEN'S FUNCTION AND THE POINTWISE BEHAVIORS OF THE VLASOV-POISSON-FOKKER-PLANCK SYSTEM 被引量:1
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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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Adsorption behavior of CO_(2)/H_(2)S mixtures in calcite slit nanopores for CO_(2) storage:An insight from molecular perspective
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作者 Cheng Qian Zhen-Hua Rui +4 位作者 Yue-Liang Liu Kai Du Chen Liu Yang Zhao Xiao-Min Ma 《Petroleum Science》 SCIE EI CAS CSCD 2024年第4期2444-2456,共13页
It is acknowledged that injecting CO_(2) into oil reservoirs and saline aquifers for storage is a practical and affordable method for CO_(2) sequestration.Most CO_(2) produced from industrial exhaust contains impurity... It is acknowledged that injecting CO_(2) into oil reservoirs and saline aquifers for storage is a practical and affordable method for CO_(2) sequestration.Most CO_(2) produced from industrial exhaust contains impurity gases such as H_(2)S that might impact CO_(2) sequestration due to competitive adsorption.This study makes a commendable effort to explore the adsorption behavior of CO_(2)/H_(2)S mixtures in calcite slit nanopores.Grand Canonical Monte Carlo(GCMC)simulation is employed to reveal the adsorption of CO_(2),H_(2)S as well as their binary mixtures in calcite nanopores.Results show that the increase in pressure and temperature can promote and inhibit the adsorption capacity of CO_(2) and H_(2)S in calcite nanopores,respectively.CO_(2)exhibits stronger adsorption on calcite surface than H_(2)S.Electrostatic energy plays the dominating role in the adsorption behavior.Electrostatic energy accounts for 97.11%of the CO_(2)-calcite interaction energy and 56.33%of the H_(2)S-calcite interaction energy at 10 MPa and 323.15 K.The presence of H_(2)S inhibits the CO_(2) adsorption in calcite nanopores due to competitive adsorption,and a higher mole fraction of H_(2)S leads to less CO_(2) adsorption.The quantity of CO_(2) adsorbed is lessened by approximately 33%when the mole fraction of H_(2)S reaches 0.25.CO_(2) molecules preferentially occupy the regions near the po re wall and H_(2)S molecules tend to reside at the center of nanopore even when the molar ratio of CO_(2) is low,indicating that CO_(2) has an adsorption priority on the calcite surface over H_(2)S.In addition,moisture can weaken the adsorption of both CO_(2) and H_(2)S,while CO_(2) is more affected.More interestingly,we find that pure CO_(2) is more suitable to be sequestrated in the shallower formations,i.e.,500-1500 m,whereas CO_(2)with H_(2)S impurity should be settled in the deeper reservoirs. 展开更多
关键词 Adsorption behavior CO_(2)/H_(2)s binary mixtures Molecular perspective Calcite slit nanopores CO_(2)sequestration
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The Impact of Comment Style on Learners’ Essay Revisions
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作者 CHEN Yang-tao 《Sino-US English Teaching》 2024年第2期73-78,共6页
This paper investigates how the type of written feedback provided by teachers affects learners’ ability to revise essays. A total of 120 participants participated in two rounds of essay composition and feedback deliv... This paper investigates how the type of written feedback provided by teachers affects learners’ ability to revise essays. A total of 120 participants participated in two rounds of essay composition and feedback delivery. The findings indicate that learners who receive comments in the form of questions are more prone to make revisions compared to those receiving statements or imperatives. These results hold significant implications for educators and the ways they utilize written feedback to enhance learners’ writing skills. 展开更多
关键词 teacher’s written feedback impact learners’essay revisions
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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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Game Analysis on Heathcliff's Behaviors in the Wuthering Heights
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作者 李晓松 《海外英语》 2013年第23期222-225,共4页
Wuthering Heights was an extraordinary novel in the nineteenth century,for it is very different from other contemporary novels which are reconciled with the public opinion by presenting Victorian values and tastes.It ... Wuthering Heights was an extraordinary novel in the nineteenth century,for it is very different from other contemporary novels which are reconciled with the public opinion by presenting Victorian values and tastes.It depicts a story of strong love and extreme hatred.This paper used the game theory to analyse the behaviors of Heathcliff in the Wuthering Heights.Some basic strategies and game models were used to illustrate the choices of the characters.This paper can be divided into four parts.The introduction is to introduce the novel,the description of the research approach and the definition of basic theories.It emphasizes on the introduction of basic strategies and some game models which would be used for the later analysis.The second part is to discuss the formation of Heathcliff's dual personality and analyses its causes.Heathcliff was very cruel in his revenge,but he also has a tender side in love,that is the manifestation of his dual personality.The formation of his dual personality dates back to his childhood suffering,the abnormal family environment,the pressure from long labor and finally his only love—Catherine's betrayal.The third part focuses on discussing how his dual personality affects Heathcliff's choices in the game plays with others.His tender personality affected Heathcliff's choice when facing Catherine's betrayal.He could not choose a grim strategy to totally break up with her,but choose a Tit for Tat and to combine with her after a revenge.His cruel personality made him harm other people indifferently which hide the foreshadowing for his death.The conclusion summarizes the arguments of this paper.This paper analyses from the formation of Heathcliff's dual personality,and then analyzes how his dual personality affected his choices in the game plays with others. 展开更多
关键词 GAME ANALYsIs Heathcliff’s behaviors
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基于Snyder希望理论的健康行为护理对老年肝硬化患者影响的研究
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作者 张姗姗 朱凌楠 +2 位作者 崔顺娟 王聪 乔园园 《现代医药卫生》 2025年第1期133-136,共4页
目的探讨基于Snyder希望理论的健康行为护理对老年肝硬化患者自护能力及健康行为的影响。方法选取2022年1月至2024年1月该院收治的89例老年肝硬化患者为研究对象,以随机数字表法分为对照组(常规护理)44例和观察组(基于Snyder希望理论的... 目的探讨基于Snyder希望理论的健康行为护理对老年肝硬化患者自护能力及健康行为的影响。方法选取2022年1月至2024年1月该院收治的89例老年肝硬化患者为研究对象,以随机数字表法分为对照组(常规护理)44例和观察组(基于Snyder希望理论的健康行为护理)45例,比较分析2组干预情况。结果干预后,观察组患者较对照组自护能力评分更高,健康认知[(78.52±4.96)分vs.(71.84±6.13)分]、健康行为[(181.43±6.49)分vs.(167.81±7.67)分]、生活质量评分均高于对照组,差异均有统计学意义(P<0.05)。结论基于Snyder希望理论的健康行为护理可提高老年肝硬化患者自护能力,改善其健康认知水平、健康行为,提高其生活质量。 展开更多
关键词 snyder希望理论 健康行为护理 肝硬化 自护能力 健康行为 生活质量
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China's English Learners' Verbal Phrase Acquisition Research Based on the Corpus——“at last”and“in the end”as an Example
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作者 张俊梅 柴晶 《海外英语》 2013年第24期262-263,287,共3页
This study is a comparative research based on corpus. This article compares China's English learners with English na?tive speakers about the use of "at last" and "in the end" from three aspects... This study is a comparative research based on corpus. This article compares China's English learners with English na?tive speakers about the use of "at last" and "in the end" from three aspects: frequency of use, location, semantic prosody. The study shows that the use of the two words are greatly different between China's English learners and English native speakers. In addition, this study discusses about causes of obvious differences and teaching enlightenments. 展开更多
关键词 at LAsT in the end" China’s English learners
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Qualitative Research on Learner's Beliefs about Learning English
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作者 王熙 《海外英语》 2016年第21期60-64,共5页
In the ESOL/SLA field, qualitative studies try to explain the language learning process not merely from psychological points of view, but also from social and cultural perspectives. In this study, a Chinese learner... In the ESOL/SLA field, qualitative studies try to explain the language learning process not merely from psychological points of view, but also from social and cultural perspectives. In this study, a Chinese learner's perceptions of mainstream English instruction in China has been investigated through the interview, and the problem was explained from social and cultural perspectives. 展开更多
关键词 quantitative researches qualitative approaches learners beliefs
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Corrosion Behavior of the S136 Mold Steel Fabricated by Selective Laser Melting 被引量:7
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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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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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A novel wavy non-uniform ligament chiral stent with J-shaped stress-strain behavior to mimic the native trachea 被引量:2
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作者 Jiapeng Liu Xinhua Yao +4 位作者 Zhenwei Wang Jian Ye Congcong Luan Jianzhong Fu Yong He 《Bio-Design and Manufacturing》 SCIE EI CSCD 2021年第4期851-866,共16页
Tracheal stents are an important form of treatment for benign or malignant central airway obstruction.However,the mechanical behavior of current tracheal stents is significantly different from that of the native trach... Tracheal stents are an important form of treatment for benign or malignant central airway obstruction.However,the mechanical behavior of current tracheal stents is significantly different from that of the native trachea,which leads to a variety of serious complications.In this study,inspired by the structure of the native trachea,a wavy non-uniform ligament chiral tracheal stent is proposed,in which J-shaped stress-strain behavior and negative Poisson's ratio response are achieved by replacing the tangential ligament of tetrachiral and anti-tetrachiral hybrid structure with a wavy non-uniform ligament.Through the combination of theoretical analysis,finite element analysis and experimental tests,a wide range of desired J-shaped stress-strain curves are explored to mimic the native porcine trachea by tailoring the stent geometry.Besides,the negative Poisson’s ratio and auxetic diameter curves versus axial strain of the stent are also studied in detail,thus contributing to the enhancement of cross-section ventilation and reducing the migration of the stent.This novel tracheal stent with a unique microstructure shows a potential to perfectly match the physiological activities of the native trachea and thereby reduce potential complications. 展开更多
关键词 Tracheobronchial stenosis Tracheal stent Chiral auxetic structure Wavy non-uniform ligament J-shaped stress-strain behavior Negative Poisson’s ratio
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Assessing gray matter volume in patients with idiopathic rapid eye movement sleep behavior disorder 被引量:3
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作者 Xian-Hua Han Xiu-Ming Li +6 位作者 Wei-Jun Tang Huan Yu Ping Wu Jing-Jie Ge Jian Wang Chuan-Tao Zuo Kuang-Yu Shi 《Neural Regeneration Research》 SCIE CAS CSCD 2019年第5期868-875,共8页
Idiopathic rapid eye movement sleep behavior disorder(iRBD) is often a precursor to neurodegenerative disease. However, voxel-based morphological studies evaluating structural abnormalities in the brains of iRBD patie... Idiopathic rapid eye movement sleep behavior disorder(iRBD) is often a precursor to neurodegenerative disease. However, voxel-based morphological studies evaluating structural abnormalities in the brains of iRBD patients are relatively rare. This study aimed to explore cerebral structural alterations using magnetic resonance imaging and to determine their association with clinical parameters in iRBD patients. Brain structural T1-weighted MRI scans were acquired from 19 polysomnogram-confirmed iRBD patients(male:female 16:3; mean age 66.6 ± 7.0 years) and 20 age-matched healthy controls(male:female 5:15; mean age 63.7 ± 5.9 years). Gray matter volume(GMV) data were analyzed based on Statistical Parametric Mapping 8, using a voxel-based morphometry method and two-sample t-test and multiple regression analysis. Compared with controls, iRBD patients had increased GMV in the middle temporal gyrus and cerebellar posterior lobe, but decreased GMV in the Rolandic operculum, postcentral gyrus, insular lobe, cingulate gyrus, precuneus, rectus gyrus, and superior frontal gyrus. iRBD duration was positively correlated with GMV in the precuneus, cuneus, superior parietal gyrus, postcentral gyrus, posterior cingulate gyrus, hippocampus, lingual gyrus, middle occipital gyrus, middle temporal gyrus, and cerebellum posterior lobe. Furthermore, phasic chin electromyographic activity was positively correlated with GMV in the hippocampus, precuneus, fusiform gyrus, precentral gyrus, superior frontal gyrus, cuneus, inferior parietal lobule, angular gyrus, superior parietal gyrus, paracentral lobule, and cerebellar posterior lobe. There were no significant negative correlations of brain GMV with disease duration or electromyographic activity in iRBD patients. These findings expand the spectrum of known gray matter modifications in iRBD patients and provide evidence of a correlation between brain dysfunction and clinical manifestations in such patients. The protocol was approved by the Ethics Committee of Huashan Hospital(approval No. KY2013-336) on January 6, 2014. This trial was registered in the ISRCTN registry(ISRCTN18238599). 展开更多
关键词 nerve REGENERATION IDIOPATHIC rapid eye movement sleep behavior disorder sYNUCLEINOPATHIEs magnetic resonance imaging gray matter volume statistic parametric mapping voxel-based MORPHOMETRY structure Parkinson’s disease NEURODEGENERATIVE diseases neural REGENERATION
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Stability constants of Sb^5+with Cl−and thermodynamics of Sb−S−Cl−H2O system involving complex behavior of Sb with Cl 被引量:1
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作者 Gang LI Yun-tao XIN +3 位作者 Xiao-dong Lü Qing-hua TIAN Kang YAN Long-gang YE 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2020年第12期3379-3389,共11页
The stability constants of Sb^5+with Cl−as well as thermodynamics of the Sb−S−Cl−H2O system were calculated.The stability constants of Sb5+with Cl−were obtained by theoretical calculations of the absorbance of a Sb5+-... The stability constants of Sb^5+with Cl−as well as thermodynamics of the Sb−S−Cl−H2O system were calculated.The stability constants of Sb5+with Cl−were obtained by theoretical calculations of the absorbance of a Sb5+-containing solution at different Cl^−concentrations,which was detected by spectrophotometric analysis at certain wavelengths of light(380 nm).The logarithmic values versus 10 of stability constants of Sb^5+with Cl−were 1.795,3.150,4.191,4.955,5.427 and 5.511,respectively,and partly filled the data gaps in the hydrometallurgy of antimony.The presence and distribution of pentavalent antimony compounds under different conditions were analyzed based on equilibrium calculations.Thermodynamic equilibrium calculations were performed for Sb−S−Cl−H2O system,which included the complex behavior of Sb with Cl,and the equilibrium equations of related reactions in this system were integrated into the potential−pH diagram. 展开更多
关键词 complex behavior stability constant thermodynamics sb−s−Cl−H2O system
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