Plants have developed sophisticated mechanisms to survive in dynamic environments.Plants can communicate via volatile organic compounds(VOCs)to warn neighboring plants of threats.In most cases,VOCs act as positive reg...Plants have developed sophisticated mechanisms to survive in dynamic environments.Plants can communicate via volatile organic compounds(VOCs)to warn neighboring plants of threats.In most cases,VOCs act as positive regulators of plant defense.However,the communication and role of volatiles in response to drought stress are poorly understood.Here,we showed that tea plants release numerous VOCs.Among them,methyl salicylate(MeSA),benzyl alcohol,and phenethyl alcohol markedly increased under drought stress.Interestingly,further experiments revealed that drought-induced MeSA lowered the abscisic acid(ABA)content in neighboring plants by reducing 9-cis-epoxycarotenoid dioxygenase(NCED)gene expression,resulting in inhibition of stomatal closure and ultimately decreasing early drought tolerance in neighboring plants.Exogenous application of ABA reduced the wilting of tea plants caused by MeSA exposure.Exposure of Nicotiana benthamiana to MeSA also led to severe wilting,indicating that the ability of drought-induced MeSA to reduce early drought tolerance in neighboring plants may be conserved in other plant species.Taken together,these results provide evidence that drought-induced volatiles can reduce early drought tolerance in neighboring plants and lay a novel theoretical foundation for optimizing plant density and spacing.展开更多
The Deep Seismic Sounding( DSS) projects carried out from the 1970 s in the lower Yangtze region and its neighboring area were reviewed in this paper,then the basic wave group features of those wide angle reflection /...The Deep Seismic Sounding( DSS) projects carried out from the 1970 s in the lower Yangtze region and its neighboring area were reviewed in this paper,then the basic wave group features of those wide angle reflection / refraction record sections,and of the crustal structure are summarized. It shows that there were in total five clear wave groups on the record sections,which include the first arrival Pg,the reflection P1 from the bottom interface of the upper crust,the reflection P3 from the bottom interface of the middle crust,the strong reflection Pm from the Moho boundary,and the refraction Pn from uppermost mantle. In general,these phases are easily consistently traced and compared,despite some first arrivals being delayed or arriving earlier than normal due to the shallow sedimentary cover or bedrocks. In particular,in the Dabie Mountain region the seismic events of a few gathered shots always have weak reflection energy,are twisted,or exhibit disorganized waveforms, which could be attributed to the disruption variations of reflection depth,the broken Moho,and the discontinuity of the reflection boundary within crust. The regional crustal structures are composed of the upper,middle and lower crust,of which the middle and lower layers can be divided into two weak reflection ones. The crustal thickness of the North China and Yangtze platform are 30km- 36 km,and the Moho exhibits a flat geometry despite some local uplifts. The average pressure velocity in lower crust beneath this two tectonic area is 6. 7 ± 0. 3km / s. Nevertheless,beneath the Dabieshan area the crustal thickness is 32km- 41 km,the Moho bends down sharply andtakes an abrupt 4km- 7km dislocation in the vertical direction. The average pressure velocity in the lower crust beneath the Dabieshan area is 6. 8 ± 0. 2km / s.展开更多
After the publication of this article 1,the authors became aware that the word of“tea”was not mentioned in the title.To make the title clear and complete,the word‘tea’is added to the title.
In the present experiment,we investigate the effects of orthodontic tooth rotation onneighboring teeth and periodontal tissues.The second maxillary incisors of 16 randomly selecteddogs were subjected to rotation at a ...In the present experiment,we investigate the effects of orthodontic tooth rotation onneighboring teeth and periodontal tissues.The second maxillary incisors of 16 randomly selecteddogs were subjected to rotation at a magnitude of 100 grams and a moment of 550 g·mm in a du-ration of 3 to 56 days.Then sections were prepared for histological examination.The findings re-vealed that,due to tooth rotation,neighboring teeth were drifted and rotated(82%),and therewere disarrangement and hyalinization of the periodontal ligament(88%),remodeling of the pe-riodontium(86%)and root resorption(32%)were also observed.These results demonstratethat tooth rotation may exert marked effects on neighboring teeth and periodontal tissues,whichmay be of important clinical significance.展开更多
By means of Logic symmetric relation,the single neighboring Logic path for Ndimensions Boolean ordered set is solved.A new method of determining any logic neighboringsubset in limited dimension is proposed.Its results...By means of Logic symmetric relation,the single neighboring Logic path for Ndimensions Boolean ordered set is solved.A new method of determining any logic neighboringsubset in limited dimension is proposed.Its results are intuitional and realizable for computer.展开更多
The Indochina Peninsula is of special and important significance to China's geopolitical strategy,which is the foothold of China's strategy in Southeast Asia and even the whole Asia-Pacific region,as well as t...The Indochina Peninsula is of special and important significance to China's geopolitical strategy,which is the foothold of China's strategy in Southeast Asia and even the whole Asia-Pacific region,as well as the strategic springboard of*China s global development.In 2016,China led the establishment of the Lancang-Mekong Cooperation mechanism,and achieved remarkable results in terms of institutional development,project implementation and the construction of international relations among member states in the short term.The establishment and rapid development of the Lancang-Mekong Cooperation is based on member states,strong willingness to cooperate.It also benefits from the rational design of their institutional structures,geographical advantages,strong and complementary economies,and close sociocultural similarities.On the other hand,the further development of the Lancang?Mekong Cooperation is facing many risks and challenges as a result of the complexities of the internal environment of the Indochina Peninsula and the geopolitical competition of extraterritorial forces in the region.In this regard,China should make more efforts to improve relevant institutional arrangements for the Lancang-Mekong Cooperation,broaden the areas and enrich the content of cooperation,coordinate with extraterritorial forces and increase the number of stakeholders.展开更多
Plants respond differently to the identity of their neighbors,such as their sex and kinship,showing plasticity in their traits.However,how the functional traits of dioecious trees are shaped by the recognition of neig...Plants respond differently to the identity of their neighbors,such as their sex and kinship,showing plasticity in their traits.However,how the functional traits of dioecious trees are shaped by the recognition of neighbors with different sex and kinship remains unknown.In this study,we set up an experiment with different kin/nonkin and inter/intrasexual combinations for a dioecious tree species,Diospyros morrisiana.The results showed that plants grew better with nonkin and intrasexual neighbors than with kin and intersexual neighbors.Kin combinations had significantly shorter root length in the resource-overlapping zone than nonkin combinations,suggesting that kin tended to reduce competition by adjusting their root distribution,especially among female siblings.Our study suggested that the seedling growth of D.morrisiana was affected by both the relatedness and sexual identity of neighboring plants.Further analysis by gas chromatography-mass spectrometry showed that the root exudate composition of female seedlings differed from that of male seedlings.Root exudates may play important roles in sex competition in dioecious plants.This study indicates that sex-specific competition and kin recognition interact and co-shape the traits of D.morrisiana seedlings,while intrasexual and nonkin neighbors facilitate the growth of seedlings.Our study implies that kin-and sex-related interactions depend on different mechanisms,kin selection,and niche partitioning,respectively.These results are critical for understanding how species coexist and how traits are shaped in nature.展开更多
Recently manifold learning algorithm for dimensionality reduction attracts more and more interests, and various linear and nonlinear,global and local algorithms are proposed. The key step of manifold learning algorith...Recently manifold learning algorithm for dimensionality reduction attracts more and more interests, and various linear and nonlinear,global and local algorithms are proposed. The key step of manifold learning algorithm is the neighboring region selection. However,so far for the references we know,few of which propose a generally accepted algorithm to well select the neighboring region. So in this paper,we propose an adaptive neighboring selection algorithm,which successfully applies the LLE and ISOMAP algorithms in the test. It is an algorithm that can find the optimal K nearest neighbors of the data points on the manifold. And the theoretical basis of the algorithm is the approximated curvature of the data point on the manifold. Based on Riemann Geometry,Jacob matrix is a proper mathematical concept to predict the approximated curvature. By verifying the proposed algorithm on embedding Swiss roll from R3 to R2 based on LLE and ISOMAP algorithm,the simulation results show that the proposed adaptive neighboring selection algorithm is feasible and able to find the optimal value of K,making the residual variance relatively small and better visualization of the results. By quantitative analysis,the embedding quality measured by residual variance is increased 45. 45% after using the proposed algorithm in LLE.展开更多
In the international community,the internal ethnic issues of one country can easily spread out of its borders through the impact of internal and external factors to affect the national security of other countries,know...In the international community,the internal ethnic issues of one country can easily spread out of its borders through the impact of internal and external factors to affect the national security of other countries,known as the spillover effect.Presently,the ethnic issues of China's neighboring countries that have real consequences on the country's national security break down mainly into four types:the internal ethnic conflict,the transnational ethnic issue,the issues related with immigrants and the collaboration of the Three Forces.The risk of spillover can be summed up according to the intensity of its effect in five categories:infiltration,springboard,spillover,immigration and harassment.As diverse ethnic issues of the neighboring countries have different effects on China's national security,the Chinese government must grasp the core element of each issue to formulate specific policies.展开更多
Seismic pounding phenomena, particularly the collision of neighboring buildings under long-period ground motion, are becoming a significant issue in Japan. We focused on a specific apartment structure called the Nuevo...Seismic pounding phenomena, particularly the collision of neighboring buildings under long-period ground motion, are becoming a significant issue in Japan. We focused on a specific apartment structure called the Nuevo Leon buildings in the Tlatelolco district of Mexico City, which consisted of three similar buildings built consecutively with narrow expansion joints between the buildings. Two out of the three buildings collapsed completely in the 1985 Mexican earthquake. Using a finite element code based on the adaptively shifted integration (ASI)-Gauss technique, a seismic pounding analysis is performed on a simulated model of the Nuevo Leon buildings to understand the impact and collapse behavior of structures built near each other. The numerical code used in the analysis provides a higher computational efficiency than the conventional code for this type of problem and enables us to address dynamic behavior with strong nonlinearities, including phenomena such as member fracture and elemental contact. Contact release and recontact algorithms are developed and implemented in the code to understand the complex behaviors of structural members during seismic pounding and the collapse sequence. According to the numerical results, the collision of the buildings may be a result of the difference of natural periods between the neighboring buildings. This difference was detected in similar buildings from the damages caused by previous earthquakes. By setting the natural period of the north building to be 25% longer than the other periods, the ground motion, which hada relatively long period of 2 s, first caused the collision between the north and the center buildings. This collision eventually led to the collapse of the centerbuilding, followed by the destruction of the north building.展开更多
There is a Chinese saying that goes like this, when stormy weather comes, a giant dragon will rise. It is the feature of the present era. When China begins to rise, it will advance at an enormous inertial force. It ha...There is a Chinese saying that goes like this, when stormy weather comes, a giant dragon will rise. It is the feature of the present era. When China begins to rise, it will advance at an enormous inertial force. It has become the important factor that influences world future trend. In the meanwhile, changes in international situation also exerted increasing influence on China. Therefore it is of special significance to discuss and assess the international environment that China faces. It展开更多
Preface One question frequently raised in discussions with colleagues from neighboring countries,and with European and American scholars who follow closely China’s neighboring relations is,how does China define its r...Preface One question frequently raised in discussions with colleagues from neighboring countries,and with European and American scholars who follow closely China’s neighboring relations is,how does China define its relations with neighboring countries?Although as early as sixty years ago,the Chinese government already provided the answer of five principles of peaceful展开更多
At the invitation of the Chinese Association for International Understanding(CAFIU),a17-member delegation of friendly people from the political circle,NGOs,think tanks and media of Bangladesh,Nepal,Indonesia,the Phili...At the invitation of the Chinese Association for International Understanding(CAFIU),a17-member delegation of friendly people from the political circle,NGOs,think tanks and media of Bangladesh,Nepal,Indonesia,the Philippines and Brunei visited China during July 19 and28.The members of the delegation were either old friends or new acquaintances of China,and therefore all boasted a lot of close links展开更多
正At the invitation of CAFIU, a 24-member delegation consisting of NGO leaders from four neighboring countries visited China from May 13 to 26. The four NGOs are Bangladesh-China People's Friendship Association (B...正At the invitation of CAFIU, a 24-member delegation consisting of NGO leaders from four neighboring countries visited China from May 13 to 26. The four NGOs are Bangladesh-China People's Friendship Association (BCPFA), Delhi Study Group (DSG)of India, Nepal Council展开更多
Systems engineering is not a new discipline. However, up to now, there is little consensus on its exact definition and scope. The scopes of several disciplines (neighboring disciplines of systems engineering) overlap ...Systems engineering is not a new discipline. However, up to now, there is little consensus on its exact definition and scope. The scopes of several disciplines (neighboring disciplines of systems engineering) overlap with that of systems engineering. In this paper, the methods to identify similarities and dissimilarities between systems engineering and its neighboring disciplines are discussed. The research of this paper is expected to be helpful for clarifying the definition and scope of systems engineering.展开更多
At the invitation of the Chinese Association for International Understanding(CAFIU),a 15-member delegation composed of delegates from NGOs,think tanks and media from Bangladesh,Indonesia,Pakistan and Sri Lanka visited...At the invitation of the Chinese Association for International Understanding(CAFIU),a 15-member delegation composed of delegates from NGOs,think tanks and media from Bangladesh,Indonesia,Pakistan and Sri Lanka visited China from July 20 to 31.During their stay in China,the delegation members listened to briefings about China’s basic national conditions and the concept of展开更多
Plant behavioral actions have been one of the major topicsof research in plant biology and agriculture.These actionsfrom plants are determined by their instant structural andphysical reactions to the circumstances(Bou...Plant behavioral actions have been one of the major topicsof research in plant biology and agriculture.These actionsfrom plants are determined by their instant structural andphysical reactions to the circumstances(Bouwmeester et al.,2019).Upon sensing abiotic factors such as salinity,flooding,high temperature,drought,plants make suitable changes intheir physiology and behavior to survive such harsh conditions.展开更多
As compared to the intuitive process that the electron emits straight to the continuum from its parent ion,there is an alternative route that the electron may transfer to and be trapped by a neighboring ionic core bef...As compared to the intuitive process that the electron emits straight to the continuum from its parent ion,there is an alternative route that the electron may transfer to and be trapped by a neighboring ionic core before the eventual release.Here,we demonstrate that electron tunnelling via the neighboring atomic core is a pronounced process in light-induced tunnelling ionization of molecules by absorbing multiple near-infrared photons.We devised a siteresolved tunnelling experiment using an Ar-Kr+ion as a prototype system to track the electron tunnelling dynamics from the Ar atom towards the neighboring Kr+by monitoring its transverse momentum distribution,which is temporally captured into the resonant excited states of the Ar-Kr+before its eventual releasing.The influence of the Coulomb potential of neighboring ionic cores promises new insights into the understanding and controlling of tunnelling dynamics in complex molecules or environment.展开更多
Polysubstituted pyrroles are very important scaffolds in many bioactive natural products and synthetic pharmaceuticals.Here,a new gold-catalyzed cycloaddition of alkynes with azadienes to access tetrasubstituted pyrro...Polysubstituted pyrroles are very important scaffolds in many bioactive natural products and synthetic pharmaceuticals.Here,a new gold-catalyzed cycloaddition of alkynes with azadienes to access tetrasubstituted pyrroles is demonstrated.The neighboring hydroxylmethyl group serves a very important directing group through an addition/cycloaddition/elimination cascade.Diverse polysubstituted pyrroles were synthesized in good yields under mild conditions in one step,and tricyclic pyrrole containing heterocycles were easily obtained through derivatization.展开更多
The short-term temperature fluctuation caused by global climate change is one of the risk factors affecting public health.Exploring the association between temperature fluctuation and diseases,which has received relat...The short-term temperature fluctuation caused by global climate change is one of the risk factors affecting public health.Exploring the association between temperature fluctuation and diseases,which has received relatively limited research attention,can contribute to enhancing awareness of health risks and taking timely measures for health risk alert and management.Therefore,this study aims to investigate the relationship between temperature change between neighboring days(TCN)and hospitalizations,identify diseases sensitive to extreme TCN,and evaluate the related disease burden.We collected meteorological and hospitalization data from 2014 to 2019 in 23 sites of China to explore the impact of TCN on hospitalizations.We first quantified site-specific associations between TCN and hospitalizations and then conducted meta-analysis to pool the results,to assess the relative risk of extreme TCN for susceptible diseases,and to estimate the related disease burden attributed to TCN.Stratified analyses were undertaken by age,sex,and disease type.Results showed that all-cause hospital admission was significantly linked to TCN.A negative TCN(below-1.9℃)in the cool season and a positive TCN(above 1.0℃)in the warm season increased the risk of hospitalization.People aged 15-64 years,men,and patients with musculoskeletal system or connective tissue diseases were more sensitive to extremely negative TCN during the cool season.People aged over 65 years,men,and patients with respiratory diseases were more sensitive to extremely positive TCN during the warm season.The attributable fraction to all-cause hospitalization from negative TCN in the cool season was 2.05%(95%CI:-0.90%,4.53%)and from positive TCN in the warm season was 5.79%(95%CI:2.98%,8.31%).Circulatory diseases in the cool season and respiratory diseases in the warm season had the highest disease burden.Our findings indicate that awareness of TCN and its health risks should be promoted and evidence-informed policies are needed to reduce the risk of TCN.展开更多
基金This work was financially supported by the National Natural Science Foundation of China(31961133030,31870678,32022076)the Science Fund for Distinguished Young Scientists of Anhui Province(1908085J12)the Deutsche Forschungsgemeinschaft(SCHW634/32-1 and SCHW634/34-1).
文摘Plants have developed sophisticated mechanisms to survive in dynamic environments.Plants can communicate via volatile organic compounds(VOCs)to warn neighboring plants of threats.In most cases,VOCs act as positive regulators of plant defense.However,the communication and role of volatiles in response to drought stress are poorly understood.Here,we showed that tea plants release numerous VOCs.Among them,methyl salicylate(MeSA),benzyl alcohol,and phenethyl alcohol markedly increased under drought stress.Interestingly,further experiments revealed that drought-induced MeSA lowered the abscisic acid(ABA)content in neighboring plants by reducing 9-cis-epoxycarotenoid dioxygenase(NCED)gene expression,resulting in inhibition of stomatal closure and ultimately decreasing early drought tolerance in neighboring plants.Exogenous application of ABA reduced the wilting of tea plants caused by MeSA exposure.Exposure of Nicotiana benthamiana to MeSA also led to severe wilting,indicating that the ability of drought-induced MeSA to reduce early drought tolerance in neighboring plants may be conserved in other plant species.Taken together,these results provide evidence that drought-induced volatiles can reduce early drought tolerance in neighboring plants and lay a novel theoretical foundation for optimizing plant density and spacing.
基金funded by the Special Public Welfare Industry Research of China Earthquake Administration(201408023)Academician Chen Yong Workstation Special Funds of Yunnan Province and Natural Science Foundation of China(41374062,41174075)
文摘The Deep Seismic Sounding( DSS) projects carried out from the 1970 s in the lower Yangtze region and its neighboring area were reviewed in this paper,then the basic wave group features of those wide angle reflection / refraction record sections,and of the crustal structure are summarized. It shows that there were in total five clear wave groups on the record sections,which include the first arrival Pg,the reflection P1 from the bottom interface of the upper crust,the reflection P3 from the bottom interface of the middle crust,the strong reflection Pm from the Moho boundary,and the refraction Pn from uppermost mantle. In general,these phases are easily consistently traced and compared,despite some first arrivals being delayed or arriving earlier than normal due to the shallow sedimentary cover or bedrocks. In particular,in the Dabie Mountain region the seismic events of a few gathered shots always have weak reflection energy,are twisted,or exhibit disorganized waveforms, which could be attributed to the disruption variations of reflection depth,the broken Moho,and the discontinuity of the reflection boundary within crust. The regional crustal structures are composed of the upper,middle and lower crust,of which the middle and lower layers can be divided into two weak reflection ones. The crustal thickness of the North China and Yangtze platform are 30km- 36 km,and the Moho exhibits a flat geometry despite some local uplifts. The average pressure velocity in lower crust beneath this two tectonic area is 6. 7 ± 0. 3km / s. Nevertheless,beneath the Dabieshan area the crustal thickness is 32km- 41 km,the Moho bends down sharply andtakes an abrupt 4km- 7km dislocation in the vertical direction. The average pressure velocity in the lower crust beneath the Dabieshan area is 6. 8 ± 0. 2km / s.
文摘After the publication of this article 1,the authors became aware that the word of“tea”was not mentioned in the title.To make the title clear and complete,the word‘tea’is added to the title.
文摘In the present experiment,we investigate the effects of orthodontic tooth rotation onneighboring teeth and periodontal tissues.The second maxillary incisors of 16 randomly selecteddogs were subjected to rotation at a magnitude of 100 grams and a moment of 550 g·mm in a du-ration of 3 to 56 days.Then sections were prepared for histological examination.The findings re-vealed that,due to tooth rotation,neighboring teeth were drifted and rotated(82%),and therewere disarrangement and hyalinization of the periodontal ligament(88%),remodeling of the pe-riodontium(86%)and root resorption(32%)were also observed.These results demonstratethat tooth rotation may exert marked effects on neighboring teeth and periodontal tissues,whichmay be of important clinical significance.
文摘By means of Logic symmetric relation,the single neighboring Logic path for Ndimensions Boolean ordered set is solved.A new method of determining any logic neighboringsubset in limited dimension is proposed.Its results are intuitional and realizable for computer.
基金a major research project funded by the National Social Science Foundation,titled “Research on the Construction of the Belt and Road Initiative and Neighboring Diplomacy”(Project No.2017010186)
文摘The Indochina Peninsula is of special and important significance to China's geopolitical strategy,which is the foothold of China's strategy in Southeast Asia and even the whole Asia-Pacific region,as well as the strategic springboard of*China s global development.In 2016,China led the establishment of the Lancang-Mekong Cooperation mechanism,and achieved remarkable results in terms of institutional development,project implementation and the construction of international relations among member states in the short term.The establishment and rapid development of the Lancang-Mekong Cooperation is based on member states,strong willingness to cooperate.It also benefits from the rational design of their institutional structures,geographical advantages,strong and complementary economies,and close sociocultural similarities.On the other hand,the further development of the Lancang?Mekong Cooperation is facing many risks and challenges as a result of the complexities of the internal environment of the Indochina Peninsula and the geopolitical competition of extraterritorial forces in the region.In this regard,China should make more efforts to improve relevant institutional arrangements for the Lancang-Mekong Cooperation,broaden the areas and enrich the content of cooperation,coordinate with extraterritorial forces and increase the number of stakeholders.
基金This work was supported by National Nonprofit Institute Research Grants of CAF(CAFYBB2017QC003),NSFC(31370441,31670628)Guangdong Basic and Applied Basic Research Foundation(2020A1515010391).
文摘Plants respond differently to the identity of their neighbors,such as their sex and kinship,showing plasticity in their traits.However,how the functional traits of dioecious trees are shaped by the recognition of neighbors with different sex and kinship remains unknown.In this study,we set up an experiment with different kin/nonkin and inter/intrasexual combinations for a dioecious tree species,Diospyros morrisiana.The results showed that plants grew better with nonkin and intrasexual neighbors than with kin and intersexual neighbors.Kin combinations had significantly shorter root length in the resource-overlapping zone than nonkin combinations,suggesting that kin tended to reduce competition by adjusting their root distribution,especially among female siblings.Our study suggested that the seedling growth of D.morrisiana was affected by both the relatedness and sexual identity of neighboring plants.Further analysis by gas chromatography-mass spectrometry showed that the root exudate composition of female seedlings differed from that of male seedlings.Root exudates may play important roles in sex competition in dioecious plants.This study indicates that sex-specific competition and kin recognition interact and co-shape the traits of D.morrisiana seedlings,while intrasexual and nonkin neighbors facilitate the growth of seedlings.Our study implies that kin-and sex-related interactions depend on different mechanisms,kin selection,and niche partitioning,respectively.These results are critical for understanding how species coexist and how traits are shaped in nature.
基金Sponsored by the National Natural Science Foundation of China (Grant No. 61101122 and 61071105)Fundamental Research Funds for the Central Universities (Grant No. HIT. NSRIF. 2010090)+1 种基金Science and Technology on Information Transmission and Dissemination in Communication Networks Laboratory (Grant No. ITD-U12004)Postdoctoral Science Research Development Foundation of Heilongjiang Province (Grant No. LBH-Q12080)
文摘Recently manifold learning algorithm for dimensionality reduction attracts more and more interests, and various linear and nonlinear,global and local algorithms are proposed. The key step of manifold learning algorithm is the neighboring region selection. However,so far for the references we know,few of which propose a generally accepted algorithm to well select the neighboring region. So in this paper,we propose an adaptive neighboring selection algorithm,which successfully applies the LLE and ISOMAP algorithms in the test. It is an algorithm that can find the optimal K nearest neighbors of the data points on the manifold. And the theoretical basis of the algorithm is the approximated curvature of the data point on the manifold. Based on Riemann Geometry,Jacob matrix is a proper mathematical concept to predict the approximated curvature. By verifying the proposed algorithm on embedding Swiss roll from R3 to R2 based on LLE and ISOMAP algorithm,the simulation results show that the proposed adaptive neighboring selection algorithm is feasible and able to find the optimal value of K,making the residual variance relatively small and better visualization of the results. By quantitative analysis,the embedding quality measured by residual variance is increased 45. 45% after using the proposed algorithm in LLE.
基金the initial result of the“Ethnic Situation of the Neighboring Countries Vs.the Ethnic Relation in China and China’s National Unity”,which is a sub-project of A Number of Important Basic Theoretical Research on Ethnic Issues under the Marxist Theory Research and Construction Project-2015
文摘In the international community,the internal ethnic issues of one country can easily spread out of its borders through the impact of internal and external factors to affect the national security of other countries,known as the spillover effect.Presently,the ethnic issues of China's neighboring countries that have real consequences on the country's national security break down mainly into four types:the internal ethnic conflict,the transnational ethnic issue,the issues related with immigrants and the collaboration of the Three Forces.The risk of spillover can be summed up according to the intensity of its effect in five categories:infiltration,springboard,spillover,immigration and harassment.As diverse ethnic issues of the neighboring countries have different effects on China's national security,the Chinese government must grasp the core element of each issue to formulate specific policies.
文摘Seismic pounding phenomena, particularly the collision of neighboring buildings under long-period ground motion, are becoming a significant issue in Japan. We focused on a specific apartment structure called the Nuevo Leon buildings in the Tlatelolco district of Mexico City, which consisted of three similar buildings built consecutively with narrow expansion joints between the buildings. Two out of the three buildings collapsed completely in the 1985 Mexican earthquake. Using a finite element code based on the adaptively shifted integration (ASI)-Gauss technique, a seismic pounding analysis is performed on a simulated model of the Nuevo Leon buildings to understand the impact and collapse behavior of structures built near each other. The numerical code used in the analysis provides a higher computational efficiency than the conventional code for this type of problem and enables us to address dynamic behavior with strong nonlinearities, including phenomena such as member fracture and elemental contact. Contact release and recontact algorithms are developed and implemented in the code to understand the complex behaviors of structural members during seismic pounding and the collapse sequence. According to the numerical results, the collision of the buildings may be a result of the difference of natural periods between the neighboring buildings. This difference was detected in similar buildings from the damages caused by previous earthquakes. By setting the natural period of the north building to be 25% longer than the other periods, the ground motion, which hada relatively long period of 2 s, first caused the collision between the north and the center buildings. This collision eventually led to the collapse of the centerbuilding, followed by the destruction of the north building.
文摘There is a Chinese saying that goes like this, when stormy weather comes, a giant dragon will rise. It is the feature of the present era. When China begins to rise, it will advance at an enormous inertial force. It has become the important factor that influences world future trend. In the meanwhile, changes in international situation also exerted increasing influence on China. Therefore it is of special significance to discuss and assess the international environment that China faces. It
文摘Preface One question frequently raised in discussions with colleagues from neighboring countries,and with European and American scholars who follow closely China’s neighboring relations is,how does China define its relations with neighboring countries?Although as early as sixty years ago,the Chinese government already provided the answer of five principles of peaceful
文摘At the invitation of the Chinese Association for International Understanding(CAFIU),a17-member delegation of friendly people from the political circle,NGOs,think tanks and media of Bangladesh,Nepal,Indonesia,the Philippines and Brunei visited China during July 19 and28.The members of the delegation were either old friends or new acquaintances of China,and therefore all boasted a lot of close links
文摘正At the invitation of CAFIU, a 24-member delegation consisting of NGO leaders from four neighboring countries visited China from May 13 to 26. The four NGOs are Bangladesh-China People's Friendship Association (BCPFA), Delhi Study Group (DSG)of India, Nepal Council
文摘Systems engineering is not a new discipline. However, up to now, there is little consensus on its exact definition and scope. The scopes of several disciplines (neighboring disciplines of systems engineering) overlap with that of systems engineering. In this paper, the methods to identify similarities and dissimilarities between systems engineering and its neighboring disciplines are discussed. The research of this paper is expected to be helpful for clarifying the definition and scope of systems engineering.
文摘At the invitation of the Chinese Association for International Understanding(CAFIU),a 15-member delegation composed of delegates from NGOs,think tanks and media from Bangladesh,Indonesia,Pakistan and Sri Lanka visited China from July 20 to 31.During their stay in China,the delegation members listened to briefings about China’s basic national conditions and the concept of
文摘Plant behavioral actions have been one of the major topicsof research in plant biology and agriculture.These actionsfrom plants are determined by their instant structural andphysical reactions to the circumstances(Bouwmeester et al.,2019).Upon sensing abiotic factors such as salinity,flooding,high temperature,drought,plants make suitable changes intheir physiology and behavior to survive such harsh conditions.
基金supported by the National Natural Science Foundation of China(Grants Nos.12374260,12241407,12074240,12204135)Hainan Provincial Natural Science Foundation of China(Grant No.122CXTD504)the Fundamental Research Funds for the Central Universities and the Sino-German Center for Research Promotion(SGC,Grant No.M-0031).
文摘As compared to the intuitive process that the electron emits straight to the continuum from its parent ion,there is an alternative route that the electron may transfer to and be trapped by a neighboring ionic core before the eventual release.Here,we demonstrate that electron tunnelling via the neighboring atomic core is a pronounced process in light-induced tunnelling ionization of molecules by absorbing multiple near-infrared photons.We devised a siteresolved tunnelling experiment using an Ar-Kr+ion as a prototype system to track the electron tunnelling dynamics from the Ar atom towards the neighboring Kr+by monitoring its transverse momentum distribution,which is temporally captured into the resonant excited states of the Ar-Kr+before its eventual releasing.The influence of the Coulomb potential of neighboring ionic cores promises new insights into the understanding and controlling of tunnelling dynamics in complex molecules or environment.
基金the financial support from the Natural Science Foundation of China and Shandong Province(Nos.21971149,92156007,ZR2019ZD45,ZR2020KB005)the Fundamental Research Funds of Shandong University。
文摘Polysubstituted pyrroles are very important scaffolds in many bioactive natural products and synthetic pharmaceuticals.Here,a new gold-catalyzed cycloaddition of alkynes with azadienes to access tetrasubstituted pyrroles is demonstrated.The neighboring hydroxylmethyl group serves a very important directing group through an addition/cycloaddition/elimination cascade.Diverse polysubstituted pyrroles were synthesized in good yields under mild conditions in one step,and tricyclic pyrrole containing heterocycles were easily obtained through derivatization.
基金supported by the Science and Technology Fundamental Resources Investigation Program of China (2017FY101201).
文摘The short-term temperature fluctuation caused by global climate change is one of the risk factors affecting public health.Exploring the association between temperature fluctuation and diseases,which has received relatively limited research attention,can contribute to enhancing awareness of health risks and taking timely measures for health risk alert and management.Therefore,this study aims to investigate the relationship between temperature change between neighboring days(TCN)and hospitalizations,identify diseases sensitive to extreme TCN,and evaluate the related disease burden.We collected meteorological and hospitalization data from 2014 to 2019 in 23 sites of China to explore the impact of TCN on hospitalizations.We first quantified site-specific associations between TCN and hospitalizations and then conducted meta-analysis to pool the results,to assess the relative risk of extreme TCN for susceptible diseases,and to estimate the related disease burden attributed to TCN.Stratified analyses were undertaken by age,sex,and disease type.Results showed that all-cause hospital admission was significantly linked to TCN.A negative TCN(below-1.9℃)in the cool season and a positive TCN(above 1.0℃)in the warm season increased the risk of hospitalization.People aged 15-64 years,men,and patients with musculoskeletal system or connective tissue diseases were more sensitive to extremely negative TCN during the cool season.People aged over 65 years,men,and patients with respiratory diseases were more sensitive to extremely positive TCN during the warm season.The attributable fraction to all-cause hospitalization from negative TCN in the cool season was 2.05%(95%CI:-0.90%,4.53%)and from positive TCN in the warm season was 5.79%(95%CI:2.98%,8.31%).Circulatory diseases in the cool season and respiratory diseases in the warm season had the highest disease burden.Our findings indicate that awareness of TCN and its health risks should be promoted and evidence-informed policies are needed to reduce the risk of TCN.
