赤道电离异常(Equatorial Ionization Anomaly,EIA)是低纬电离层中的一个重要现象.本文基于IGS台网提供的2001-2008年期间的电离层总电子含量(Total Electron Content,TEC)数据,分析了120°E区的EIA强度和磁南北半球不对称性在磁平...赤道电离异常(Equatorial Ionization Anomaly,EIA)是低纬电离层中的一个重要现象.本文基于IGS台网提供的2001-2008年期间的电离层总电子含量(Total Electron Content,TEC)数据,分析了120°E区的EIA强度和磁南北半球不对称性在磁平静时期的变化特征,包括对地方时、季节和太阳活动的依赖.本文结果表明,(1)EIA强度表现出显著的随地方时和季节的变化特征.EIA强度在0200LT和2000LT附近分别出现一个极值,且2000LT附近的EIA强度更大;EIA强度通常在春/秋季较大,在夏/冬季较小,且冬季要大于夏季.(2)EIA南北半球不对称也表现出随地方时和季节变化特征.EIA半球不对称在0200LT和2000-2200LT附近分别出现一个极值;EIA半球不对称的季节变化特征还依赖于太阳活动,太阳活动高年期间,EIA半球不对称通常在春/秋季更显著;太阳活动低年期间,EIA半球不对称通常在冬季更显著.(3)EIA强度和半球不对称性的逐日变化和月变化表现出对太阳活动存在一定的依赖,但依赖性并不显著.2000LT(0200LT)附近的EIA强度的月变化与太阳活动整体呈正(负)相关,而2200LT(0200LT)附近的EIA半球不对称的月变化与太阳活动整体呈负(负)相关.(4)影响EIA强度变化的主要因素可归于纬圈电场和中性风场;影响EIA半球不对称变化的主要因素可归因为子午中性风场.展开更多
Brain asymmetry,involving structural and functional differencesbetween the two hemispheres,is a major organizational principle ofthe human brain.The structural and functional connectivity withineach hemisphere defines...Brain asymmetry,involving structural and functional differencesbetween the two hemispheres,is a major organizational principle ofthe human brain.The structural and functional connectivity withineach hemisphere defines the hemispheric network or connectome.Elucidating left-right differences of the hemispheric network providesopportunities for brain asymmetry exploration.This review examinesthe asymmetry in the hemispheric white matter and functionalnetwork to assess health and brain disorders.In this article,the brain asymmetry in structural and functional connectivity includingnetwork topologies of healthy individuals,involving brain cognitivesystems and the development trend,is highlighted.Moreover,theabnormal asymmetry of the hemispheric network related to cognition changes in brain disorders,such as Alzheimer’s disease,schizophrenia,autism spectrum disorder,attention deficit hyperactivity disorder,and bipolar disorder,is presented.This review suggests that thehemispheric network is highly conserved for measuring human brain asymmetries and has potential in the study of the cognitivesystem and brain disorders.展开更多
A study examining affective information processing in persons with Multiple Sclerosis and healthy adults was carried out. It was hypothesized that individual characteristics could modulate participants’ emotional cat...A study examining affective information processing in persons with Multiple Sclerosis and healthy adults was carried out. It was hypothesized that individual characteristics could modulate participants’ emotional categorization and reaction times for categorization decisions. For example, individuals with negative valenced emotional profile (e.g. anxious) should choose negative emotional alternatives faster and more frequently. Participants consisted of two different populations: 80 right-handed healthy French-speakers, and 40 right-handed French- speakers with multiple sclerosis. The results showed a positive correlation between high- level of negative emotional sensibility and emotional categorization (decision and decision speed) for affective information presented on the right-side of the screen. For all participants there were more frequent emotional choices and faster decisions for left-side presented emotional alternatives. It seems individuals’ emotional differences in general and in MS populations modulate hemispheric asymmetry of processing emotional judgments.展开更多
The indigenous population of the North can efficiently preserve health and vital activity, and reproduce new generations under extreme climatic and geographic conditions due to peculiar way of life, mental features, r...The indigenous population of the North can efficiently preserve health and vital activity, and reproduce new generations under extreme climatic and geographic conditions due to peculiar way of life, mental features, rituals, regimes of work and rest, social and cultural traditions. Of great importance are also the clothes which are favorable for keeping heat and self-cleaning, some psycho-therapeutic factors (rituals of shamanism), animal food and vegetables. The phenotype of the adaptation reserves of an organism, northern type of metabolism, dominance of the right brain hemisphere play a great role, so does the adaptation of national mentality to the harmony of inner human state with the extreme environmental conditions of high latitudes.展开更多
Although much has been done on the hemispheric asymmetry (or seasonal variations) of auroral hemispheric power (HP), the dependence of HP hemispheric asymmetry on solar cycle has not yet been studied. We have analyzed...Although much has been done on the hemispheric asymmetry (or seasonal variations) of auroral hemispheric power (HP), the dependence of HP hemispheric asymmetry on solar cycle has not yet been studied. We have analyzed data during 1979-2010 and investigated the dependence of HP hemispheric asymmetry/seasonal variation for the whole solar cycle. Here we show that (1) the hemispheric asymmetry of HP is positively correlated to the value of solar F10.7 with some time delay; (2) it is closely related to the coupling function between the solar wind and magnetosphere; and (3) the winter hemisphere receives more auroral power than the summer hemisphere for Kp ~0 to 6. The statistic results can be partly understood in the framework of the ionospheric conductivity feedback model. The similarity and differences between our results and previous results are discussed in the paper.展开更多
When a global moving pattern is superimposed on high-contrast stationary or slowly moving stimuli, the stimuli can be perceived as disappearing and reappearing alternately for periods of several sec- onds.This visual ...When a global moving pattern is superimposed on high-contrast stationary or slowly moving stimuli, the stimuli can be perceived as disappearing and reappearing alternately for periods of several sec- onds.This visual illusory phenomenon was named“motion-induced blindness”(MIB)in recent litera- ture.So far there is no consensus on the mechanism of MIB,especially on the role of attention in this phenomenon.To examine the effect of spatial attention on MIB,the present study manipulated the participants’spatial attention by asking them to respond to two targets simultaneously presented in bilateral visual fields(the divided-attention condition)or only respond to one of them(the fo- cused-attention condition).A central arrow was presented as an endogenous cue to index the target visual field in the focused-attention condition,while a point was presented instead in the di- vided-attention condition.The results show that the percentage of accumulated invisibility period was larger for the targets in the focused-attention condition than for those in the divided-attention condition. This effect of attention is significant in upper visual field(UVF)and left lower visual field(left LVF);that is,this effect shows a hemispheric asymmetry in LVF but not in UVF.Furthermore,the percentage of accumulated invisibility period was larger for targets in left LVF than for those in right LVF in the fo- cused-attention condition,but no hemispheric asymmetry was found in the divided-attention condition. In addition,the increased percentage of accumulated invisibility period in the focused-attention condi- tion originated merely in the enhancement of the mean phase duration of disappearance in LVF,while the disappearance occurred more frequently and lasted longer for each occurrence,which led to an increase in the total invisibility period,in the focused-than divided-attention condition in UVF.These results suggest that the modulation of spatial attention on MIB has different patterns in UVF and LVF.展开更多
文摘赤道电离异常(Equatorial Ionization Anomaly,EIA)是低纬电离层中的一个重要现象.本文基于IGS台网提供的2001-2008年期间的电离层总电子含量(Total Electron Content,TEC)数据,分析了120°E区的EIA强度和磁南北半球不对称性在磁平静时期的变化特征,包括对地方时、季节和太阳活动的依赖.本文结果表明,(1)EIA强度表现出显著的随地方时和季节的变化特征.EIA强度在0200LT和2000LT附近分别出现一个极值,且2000LT附近的EIA强度更大;EIA强度通常在春/秋季较大,在夏/冬季较小,且冬季要大于夏季.(2)EIA南北半球不对称也表现出随地方时和季节变化特征.EIA半球不对称在0200LT和2000-2200LT附近分别出现一个极值;EIA半球不对称的季节变化特征还依赖于太阳活动,太阳活动高年期间,EIA半球不对称通常在春/秋季更显著;太阳活动低年期间,EIA半球不对称通常在冬季更显著.(3)EIA强度和半球不对称性的逐日变化和月变化表现出对太阳活动存在一定的依赖,但依赖性并不显著.2000LT(0200LT)附近的EIA强度的月变化与太阳活动整体呈正(负)相关,而2200LT(0200LT)附近的EIA半球不对称的月变化与太阳活动整体呈负(负)相关.(4)影响EIA强度变化的主要因素可归于纬圈电场和中性风场;影响EIA半球不对称变化的主要因素可归因为子午中性风场.
基金This work was supported by the National Natural Science Foundation of China(Grant Nos.62176177,61906130)the National Key R&D Program of China(Grant No.2018AAA0102604)+1 种基金the Natural Science Foundation of Shanxi(Grant No.20210302123112)the Research Project Supported by Shanxi Scholarship Council of China(Grant No.2021-039).
文摘Brain asymmetry,involving structural and functional differencesbetween the two hemispheres,is a major organizational principle ofthe human brain.The structural and functional connectivity withineach hemisphere defines the hemispheric network or connectome.Elucidating left-right differences of the hemispheric network providesopportunities for brain asymmetry exploration.This review examinesthe asymmetry in the hemispheric white matter and functionalnetwork to assess health and brain disorders.In this article,the brain asymmetry in structural and functional connectivity includingnetwork topologies of healthy individuals,involving brain cognitivesystems and the development trend,is highlighted.Moreover,theabnormal asymmetry of the hemispheric network related to cognition changes in brain disorders,such as Alzheimer’s disease,schizophrenia,autism spectrum disorder,attention deficit hyperactivity disorder,and bipolar disorder,is presented.This review suggests that thehemispheric network is highly conserved for measuring human brain asymmetries and has potential in the study of the cognitivesystem and brain disorders.
文摘A study examining affective information processing in persons with Multiple Sclerosis and healthy adults was carried out. It was hypothesized that individual characteristics could modulate participants’ emotional categorization and reaction times for categorization decisions. For example, individuals with negative valenced emotional profile (e.g. anxious) should choose negative emotional alternatives faster and more frequently. Participants consisted of two different populations: 80 right-handed healthy French-speakers, and 40 right-handed French- speakers with multiple sclerosis. The results showed a positive correlation between high- level of negative emotional sensibility and emotional categorization (decision and decision speed) for affective information presented on the right-side of the screen. For all participants there were more frequent emotional choices and faster decisions for left-side presented emotional alternatives. It seems individuals’ emotional differences in general and in MS populations modulate hemispheric asymmetry of processing emotional judgments.
文摘The indigenous population of the North can efficiently preserve health and vital activity, and reproduce new generations under extreme climatic and geographic conditions due to peculiar way of life, mental features, rituals, regimes of work and rest, social and cultural traditions. Of great importance are also the clothes which are favorable for keeping heat and self-cleaning, some psycho-therapeutic factors (rituals of shamanism), animal food and vegetables. The phenotype of the adaptation reserves of an organism, northern type of metabolism, dominance of the right brain hemisphere play a great role, so does the adaptation of national mentality to the harmony of inner human state with the extreme environmental conditions of high latitudes.
基金supported by Ocean Public Welfare Scientific Research Project, State Oceanic Administration People’s Republic of China (201005017)the National Basic Research Program of China(2011CB811404)
文摘Although much has been done on the hemispheric asymmetry (or seasonal variations) of auroral hemispheric power (HP), the dependence of HP hemispheric asymmetry on solar cycle has not yet been studied. We have analyzed data during 1979-2010 and investigated the dependence of HP hemispheric asymmetry/seasonal variation for the whole solar cycle. Here we show that (1) the hemispheric asymmetry of HP is positively correlated to the value of solar F10.7 with some time delay; (2) it is closely related to the coupling function between the solar wind and magnetosphere; and (3) the winter hemisphere receives more auroral power than the summer hemisphere for Kp ~0 to 6. The statistic results can be partly understood in the framework of the ionospheric conductivity feedback model. The similarity and differences between our results and previous results are discussed in the paper.
文摘洋岛玄武岩 (OIB)氦同位素组成 (3 He 4 He)在地理分布上具有非均匀性特征。3 He 4 He值为 5～ 6Ra 的OIB主要分布在南半球 ,而分布于冰岛和夏威夷 (包括Loihi)等地的OIB3 He 4 He值为 10～ 35Ra。低3 He 4 He值OIB具有富集大离子亲石元素U、Th的源区 ,由于U、Th衰变释放的4He同位素的积累导致其3 He 4 He值降低。该源区的形成是俯冲作用导致深海沉积物与地幔混合 ,其地理分布受Pangea大陆周边的古俯冲带制约。高3 He 4 He值OIB的源区则是亏损U、Th的地幔胞 (mantleblob) ,该地幔胞是由极度亏损U、Th的再循环洋壳或大陆下地壳与未排气的地幔胞混合形成的。经过 1～ 2Ga的演化形成即相对亏损4He同位素而3 He 4 He值高的源区。同时 ,这种地幔胞富集难融组分 ,所以较洋中脊玄武岩 (MORB)的源区更为稳定 ,即高3 He 4 He值源区的部分熔融需要更高的地幔温度。超级地幔柱上升可以导致地幔升温和高3 He 4 He值源区的熔融。3 He 4 He值OIB地理分布的非均匀性反映出全球地幔对流系统复杂的半球非对称性格局。
基金Supported by the National Natural Science Foundation of China(Grant Nos.30470570 and 30100053)
文摘When a global moving pattern is superimposed on high-contrast stationary or slowly moving stimuli, the stimuli can be perceived as disappearing and reappearing alternately for periods of several sec- onds.This visual illusory phenomenon was named“motion-induced blindness”(MIB)in recent litera- ture.So far there is no consensus on the mechanism of MIB,especially on the role of attention in this phenomenon.To examine the effect of spatial attention on MIB,the present study manipulated the participants’spatial attention by asking them to respond to two targets simultaneously presented in bilateral visual fields(the divided-attention condition)or only respond to one of them(the fo- cused-attention condition).A central arrow was presented as an endogenous cue to index the target visual field in the focused-attention condition,while a point was presented instead in the di- vided-attention condition.The results show that the percentage of accumulated invisibility period was larger for the targets in the focused-attention condition than for those in the divided-attention condition. This effect of attention is significant in upper visual field(UVF)and left lower visual field(left LVF);that is,this effect shows a hemispheric asymmetry in LVF but not in UVF.Furthermore,the percentage of accumulated invisibility period was larger for targets in left LVF than for those in right LVF in the fo- cused-attention condition,but no hemispheric asymmetry was found in the divided-attention condition. In addition,the increased percentage of accumulated invisibility period in the focused-attention condi- tion originated merely in the enhancement of the mean phase duration of disappearance in LVF,while the disappearance occurred more frequently and lasted longer for each occurrence,which led to an increase in the total invisibility period,in the focused-than divided-attention condition in UVF.These results suggest that the modulation of spatial attention on MIB has different patterns in UVF and LVF.
