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A Way to Rootedness: Traveling in Tender Is the Night
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作者 王广 《海外英语》 2015年第6期196-197,共2页
Traveling is one major theme of Fitzgerald's novel Tender Is the Night. This fashionable activity for the 1920 s Americans is represented in the novel as ostensibly bearing different meanings to the main character... Traveling is one major theme of Fitzgerald's novel Tender Is the Night. This fashionable activity for the 1920 s Americans is represented in the novel as ostensibly bearing different meanings to the main characters, but a deeper look would reveal that it is unanimously resorted to as a weapon against the spiritual barrenness caused by the cult of business, and more importantly, as a way to the experience of rootedness. 展开更多
关键词 TRAVELING rootedness SPIRITUAL barrenness CULT of business FITZGERALD TENDER Is the NIGHT
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COUNTING ROOTED EULERIAN MAPS ON THE PROJECTIVE PLANE
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作者 任韩 刘彦佩 《Acta Mathematica Scientia》 SCIE CSCD 2000年第2期169-174,共6页
It is well known that any kind of exact enumerations of rooted maps on nonplanar surface is quite difficult. This paper presents a functional equation for rooted Eulerian maps on the projective plane. A parametric exp... It is well known that any kind of exact enumerations of rooted maps on nonplanar surface is quite difficult. This paper presents a functional equation for rooted Eulerian maps on the projective plane. A parametric expression, through which an exact enumeration by root-valency and the number of edges of maps may be determined, is obtained. 展开更多
关键词 (rooted)Map surface LAGRANGIAN INVERSION enufunction
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Rooted Tree Optimization for Wind Turbine Optimum Control Based on Energy Storage System
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作者 Billel Meghni Afaf Benamor +7 位作者 Oussama Hachana Ahmad Taher Azar Amira Boulmaiz Salah Saad El-Sayed M.El-kenawy Nashwa Ahmad Kamal Suliman Mohamed Fati Naglaa K.Bahgaat 《Computers, Materials & Continua》 SCIE EI 2023年第2期3977-3996,共20页
The integration of wind turbines(WTs)in variable speed drive systems belongs to the main factors causing lowstability in electrical networks.Therefore,in order to avoid this issue,WTs hybridization with a storage syst... The integration of wind turbines(WTs)in variable speed drive systems belongs to the main factors causing lowstability in electrical networks.Therefore,in order to avoid this issue,WTs hybridization with a storage system is a mandatory.This paper investigates WT system operating at variable speed.The system contains of a permanent magnet synchronous generator(PMSG)supported by a battery storage system(BSS).To enhance the quality of active and reactive power injected into the network,direct power control(DPC)scheme utilizing space-vector modulation(SVM)technique based on proportional-integral(PI)control is proposed.Meanwhile,to improve the rendition of this method(DPC-SVM-PI),the rooted tree optimization technique(RTO)algorithm-based controller parameter identification is used to achieve PI optimal gains.To compare the performance ofRTO-based controllers,they were implemented and tested along with some other popular controllers under different working conditions.The obtained results have shown the supremacy of the suggested PIRTO algorithm compared to competing controllers regarding total harmonic distortion(THD),overshoot percentage,settling time,rise time,average active power value,overall efficiency,and active power steadystate error. 展开更多
关键词 rooted tree optimization(RTO)method direct power control(DPC) wind turbine(WT) proportional integral(PI) PMSG
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Analysis of Poverty Performance and Its Rooted Causes of the Aid-Poverty- Development Counties in Sichuan
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作者 Shen Mao-yingInstitute of Mountain Hazards and Environment, Chinese Academy of Sciences, Chengdu 610041, Sichuan, China Sichuan Academy of Social Sciences, Chengdu 610072, Sichuan, China 《Wuhan University Journal of Natural Sciences》 CAS 2003年第03B期911-918,共8页
There are 36 counties affirmed to be aid-poverty-development county in the early 21st century, which distribute around the circumferential mountain of Sichuan Basin, According to the topographic features and the distr... There are 36 counties affirmed to be aid-poverty-development county in the early 21st century, which distribute around the circumferential mountain of Sichuan Basin, According to the topographic features and the distribution of nationality, these aid-poverty-development counties can be classified into 4 depressed-regions. Study shows that regional poverty performance of 4 depressed-regions not only has many commons in the field of regional economic structure and industry structure, which is far behind the average development performance of Sichuan in the field of economic sum per capita such as GDP, farmer net income per capita as well as retail scale consumer goods, it is also quite different related to infrastructure and social development within 4 depressed-regions. Regional Poverty is chronically resulted in interaction of the multi-factors. Natural condition constraint is the basic factor contributed to regional poverty, policy influences play key role, the poor culture is inherent factor to regional poverty and the marginal locations play important role. 展开更多
关键词 aid-poverty-development counties (APDCs) regional poverty performance (RPP) rooted cause
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Preliminary Study on Water Demand Law of 1-0 Rooted Cuttings of Populus szechuanica
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作者 Dabuqiong Haoyu WANG +2 位作者 Huanhuan XIE Zhen XING Yanhui YE 《Meteorological and Environmental Research》 CAS 2021年第4期39-42,共4页
In order to provide theoretical basis and technical support for the afforestation and artificial water supply of P.szechuanica in arid areas,the characteristics of water consumption of P.szechuanica were explored,and ... In order to provide theoretical basis and technical support for the afforestation and artificial water supply of P.szechuanica in arid areas,the characteristics of water consumption of P.szechuanica were explored,and the law of water demand of P.szechuanica was grasped.In this paper,potted seedlings of 1-0 rooted cuttings of P.szechuanica were taken as research objects,and change situation of water consumption under different water control gradients was measured regularly by using weighing method,further analyzing dynamic change of water consumption of P.szechuanica and revealing water demand law of 1-0 rooted cuttings of P.szechuanica.The results showed that total change of water consumption of 1-0 rooted cuttings of P.szechuanica had"slow-fast-slow-fast"double-peak trend in the growth period of the current year,and corresponded with univariate linear relation(R^(2)=0.7137),with significant difference.In whole growth period,water consumption in August was the highest,which was 2.7 times of that in June and July and 1.5 times of that after September.In different water control treatments,the dynamic changes of daily and monthly water consumption were significantly different.In seven water control treatments,monthly water consumption was between(6315.95±1690.70)and(10105.28±3065.30)g/month,and mean was(8211.07±2308.23)g/month.With intensification of water control treatment,water consumption increased,but there was no seedling death due to water shortage.P.szechuanica has great plasticity in water demand,and can survive in both arid and humid environments.Meanwhile,it is revealed that P.szechuanica is the most widely distributed tree species in the region. 展开更多
关键词 Populus szechuanica 1-0 rooted cuttings Water consumption Water demand law
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ON THE VERTEX PARTITION EQUATION OF ROOTED LOOPLESS PLANAR MAPS
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作者 刘彦佩 《Acta Mathematica Scientia》 SCIE CSCD 1990年第2期167-172,共6页
This paper provides a functional equation astisfied by the generating function for enumerating rooted loopless planar maps with vertex partition. A kind of applications in enumerating, by providing explicit formulae, ... This paper provides a functional equation astisfied by the generating function for enumerating rooted loopless planar maps with vertex partition. A kind of applications in enumerating, by providing explicit formulae, a type of rooted loopless planar maps with the maximum valency of vertices given are described. Meanwhile, the functional equation for enumerating rooted loopless planar maps (connected) with the edge number and the valency of root-vertex as the parameters is also derived directly. 展开更多
关键词 ON THE VERTEX PARTITION EQUATION OF rooted LOOPLESS PLANAR MAPS
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A study of the rotation rate of single-rooted teeth in dogs
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作者 段银钟 陈华 张巧余 《Journal of Medical Colleges of PLA(China)》 CAS 1992年第1期70-72,共3页
Sixteen one-year-old dogs were used in our experiment.We rotated the maxillary secondincisors of the dogs,applying a force of 100g and a moment of 550g·mm.The duration of theexperiment varied from 72h to 8 weeks.... Sixteen one-year-old dogs were used in our experiment.We rotated the maxillary secondincisors of the dogs,applying a force of 100g and a moment of 550g·mm.The duration of theexperiment varied from 72h to 8 weeks.Activation was performed once every 2 weeks and the impressions were taken in order to measure the angles of rotation.The results of our experiment showthat the rotation rate of single-rooted tooth in dogs is 3.04/week.The graph shows the form ofgradual stairs.This paper introduces a new specialized experimental apparatus for tooth rotation.The angles of rotation are measured geometrically. 展开更多
关键词 TOOTH ROTATION TOOTH ROOT INCISOR ANIMAL experiment DOGS
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Water adaptive traits of deep-rooted C_3 halophyte(Karelinia caspica(Pall.) Less.) and shallow-rooted C_4 halophyte(Atriplex tatarica L.) in an arid region,Northwest China
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作者 Yuan FAN PinFang LI +3 位作者 ZhenAn HOU TuSheng REN ChunLian XIONG Biao ZHANG 《Journal of Arid Land》 SCIE 2012年第4期469-478,共10页
This paper focused on the water relations of two halophytes differing in photosynthetic pathway, phe- notype, and life cycle: Karelinia caspica (Pall.) Less. (C3, deep-rooted perennial Asteraceae grass) and Atrip... This paper focused on the water relations of two halophytes differing in photosynthetic pathway, phe- notype, and life cycle: Karelinia caspica (Pall.) Less. (C3, deep-rooted perennial Asteraceae grass) and Atriplex tatarica L. (C4, shallow-rooted annual Chenopodiaceae grass). Gas exchange, leaf water potential, and growth characteristics were investigated in two growing seasons in an arid area of Xinjiang to explore the physiological adaptability of the two halophytes. Both K. caspica and A. tatarica showed midday depression of transpiration, in- dicating that they were strong xerophytes and weak midday depression types. The roots of A. tatarica were con- centrated mainly in the 0-60 cm soil layer, and the leaf water potential (~L) increased sharply in the 0-20 cm layer due to high soil water content, suggesting that the upper soil was the main water source. On the other hand, K. caspica had a rooting depth of about 1.5 m and a larger root/shoot ratio, which confirmed that this species uptakes water mainly from deeper soil layer. Although A. tatarica had lower transpiration water consumption, higher water use efficiency (WUE), and less water demand at the same leaf water potential, it showed larger water stress impact than K. caspica, indicating that the growth of A. tatarica was restricted more than that of K. caspica when there was no rainfall recharge. As a shallow-rooted C4 species, A. tatarica displayed lower stomatal conductance, which could to some extent reduce transpiration water loss and maintain leaf water potential steadily. In contrast, the deep-rooted C3 species K. caspica had a larger root/shoot ratio that was in favor of exploiting groundwater. We concluded that C3 species (K. caspica) tapes water and C4 species (A. tatarica) reduces water loss to survive in the arid and saline conditions. The results provided a case for the phenotype theory of Schwinning and Ehleringer on halophytic plants. 展开更多
关键词 Karelinia caspica Atriplex tatarica root/shoot ratio leaf water potential stomatal conductance TRANSPIRATION
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Heat Transfer Enhancement via Combined Wall and Triangular Rooted-Fin System
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作者 Abdul Rahim A. Khaled Abdullatif A. Gari 《Journal of Electronics Cooling and Thermal Control》 2014年第1期12-21,共10页
This work analyzes heat transfer through a wall containing triangular fins partially embedded in its volume. The coupled heat diffusion equations governing each constituent are solved numericallyusing an iterative fin... This work analyzes heat transfer through a wall containing triangular fins partially embedded in its volume. The coupled heat diffusion equations governing each constituent are solved numericallyusing an iterative finite volume method. A well bracketed effectiveness of the combined system that suits wide range of applications is analytically derived. Good agreement between the numerical and the analytical results is attained. It is found that the fin-root can act simultaneously as a heat sink and heat source for the wall. The heat transfer rate through the combined system is clearly seen to be maximized at a specific fin-root length. The maximum reported heat transfer rate through the triangular rooted-finned wall is found to be at most 90% above that for the rootless fin case at wall Biot number of 1.54. This percentage is noticed to decrease as the wall Biot number decreases. At that Biot number, the maximum heat transfer rate through the combined system reaches 150% above that through the plain wall. As a result of this work, it is recommended to utilize the triangular rooted-fin as a heat transfer enhancer for high mechanical strength structures exposed to highly convective fluid streams. 展开更多
关键词 Conduction CONVECTION FINS Augmentation ROOTS Thermal SYSTEM
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Completeness of Induced Cotorsion Pairs in Representation Categories of Rooted Quivers
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作者 Zhen Xing DI Li Ping LI +1 位作者 Li LIANG Fei XU 《Acta Mathematica Sinica,English Series》 SCIE CSCD 2024年第10期2436-2452,共17页
This paper focuses on a question raised by Holm and Jorgensen,who asked if the induced cotorsion pairs(Φ(X),Φ(X)^(⊥))and(^(⊥)Ψ(Y),Ψ(Y))in Rep(Q,A)—the category of all A-valued representations of a quiver Q—are... This paper focuses on a question raised by Holm and Jorgensen,who asked if the induced cotorsion pairs(Φ(X),Φ(X)^(⊥))and(^(⊥)Ψ(Y),Ψ(Y))in Rep(Q,A)—the category of all A-valued representations of a quiver Q—are complete whenever(X,Y)is a complete cotorsion pair in an abelian category A satisfying some mild conditions.We give an affirmative answer if the quiver Q is rooted.As an application,we show under certain mild conditions that if a subcategory L,which is not necessarily closed under direct summands,of A is special precovering(resp.,preenveloping),thenΦ(L)(resp.,Ψ(L))is special precovering(resp.,preenveloping)in Rep(Q,A). 展开更多
关键词 rooted quiver complete cotorsion pair special precovering(preenveloping)subcategory
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Structure Polynomials and Subgraphs of Rooted Regular Trees
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作者 Daniele D'Angeli Alfredo Donno 《Algebra Colloquium》 SCIE CSCD 2018年第1期45-70,共26页
We introduce an algebraic structure allowing us to describe subgraphs of a regular rooted tree. Its elements are called structure polynomials, and they are in a one- to-one correspondence with the set of all subgraphs... We introduce an algebraic structure allowing us to describe subgraphs of a regular rooted tree. Its elements are called structure polynomials, and they are in a one- to-one correspondence with the set of all subgraphs of the tree. We define two operations, the sum and the product of structure polynomials, giving a graph interpretation of them. Then we introduce an equivalence relation between polynomials, using the action of the full automorphism group of the tree, and we count equivalence classes of subgraphs modulo this equivalence. We also prove that this action gives rise to symmetric Gelfand pairs. Finally, when the regularity degree of the tree is a prime p, we regard each level of the tree as a finite dimensional vector space over the finite field Fp, and we are able to completely characterize structure polynomials corresponding to subgraphs whose leaf set is a vector subspace. 展开更多
关键词 rooted tree structure polynomial rooted subtree automorphism group of a tree Gelfand pair
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Bearing capacity and load transfer mechanism of a static drill rooted nodular pile in soft soil areas 被引量:18
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作者 Jia-jin ZHOU Kui-hua WANG +1 位作者 Xiao-nan GONG Ri-hong ZHANG 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2013年第10期705-719,共15页
The static drill rooted nodular pile is a new type of pile foundation consisting of precast nodular pile and the surrounding cemented soil.This composite pile has a relatively high bearing capacity and the mud polluti... The static drill rooted nodular pile is a new type of pile foundation consisting of precast nodular pile and the surrounding cemented soil.This composite pile has a relatively high bearing capacity and the mud pollution will be largely reduced during the construction process by using this type of pile.In order to investigate the bearing capacity and load transfer mechanism of this pile,a group of experiments were conducted to provide a comparison between this new pile and the bored pile.The axial force of a precast nodular pile was also measured by the strain gauges installed on the pile to analyze the distribution of the axial force of the nodular pile and the skin friction supported by the surrounding soil,then 3D models were built by using the ABAQUS finite element program to investigate the load transfer mechanism of this composite pile in detail.By combining the results of field tests and the finite element method,the outcome showed that the bearing capacity of a static drill rooted nodular pile is higher than the bored pile,and that this composite pile will form a double stress dispersion system which will not only confirm the strength of the pile,but also make the skin friction to be fully mobilized.The settlement of this composite pile is mainly controlled by the precast nodular pile;meanwhile,the nodular pile and the surrounding cemented soil can be considered as deformation compatibility during the loading process.The nodes on the nodular pile play an important role during the load transfer process,the shear strength of the interface between the cemented soil and the soil of the static drill rooted pile is larger than that of the bored pile. 展开更多
关键词 Static drill rooted nodular pile Load transfer Bearing capacity ABAQUS Double stress dispersion system Three-dimensional modeling
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New Expected Value Expansions of Rooted Graphs 被引量:1
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作者 Xiao-qing TANG 《Acta Mathematicae Applicatae Sinica》 SCIE CSCD 2015年第1期81-88,共8页
We propose a new expected value of rooted graph in this article,that is, when G is a rooted graph that each vertex may independently succeed with probability p when catastrophic thing happened, we consider the expecte... We propose a new expected value of rooted graph in this article,that is, when G is a rooted graph that each vertex may independently succeed with probability p when catastrophic thing happened, we consider the expected number of edges in the operational component of G which containing the root. And we get a very important and useful compute formula which is called deletion-contraction edge formula. By using this formula, we get the computational formulas of expected value for some special graphs. We also discuss the mean of expected value when parameter p has certain prior distribution. Finally, we propose mean-variance optimality when rooted graph has the equilibrium point which has larger mean and smaller variance. 展开更多
关键词 rooted graph expected value deletion-contraction edge formula mean-variance optimality
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Protein arginine methyltransferase-6 regulates heterogeneous nuclear ribonucleoprotein-F expression and is a potential target for the treatment of neuropathic pain
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作者 Xiaoyu Zhang Yuqi Liu +6 位作者 Fangxia Xu Chengcheng Zhou Kaimei Lu Bin Fang Lijuan Wang Lina Huang Zifeng Xu 《Neural Regeneration Research》 SCIE CAS 2025年第9期2682-2696,共15页
Protein arginine methyltransferase-6 participates in a range of biological functions,particularly RNA processing,transcription,chromatin remodeling,and endosomal trafficking.However,it remains unclear whether protein ... Protein arginine methyltransferase-6 participates in a range of biological functions,particularly RNA processing,transcription,chromatin remodeling,and endosomal trafficking.However,it remains unclear whether protein arginine methyl transferase-6 modifies neuropathic pain and,if so,what the mechanisms of this effect.In this study,protein arginine methyltransferase-6 expression levels and its effect on neuropathic pain were investigated in the spared nerve injury model,chronic constriction injury model and bone cancer pain model,using immunohistochemistry,western blotting,immunoprecipitation,and label-free proteomic analysis.The results showed that protein arginine methyltransferase-6 mostly co-localized withβ-tubulinⅢin the dorsal root ganglion,and that its expression decreased following spared nerve injury,chronic constriction injury and bone cancer pain.In addition,PRMT6 knockout(Prmt6~(-/-))mice exhibited pain hypersensitivity.Furthermore,the development of spared nerve injury-induced hypersensitivity to mechanical pain was attenuated by blocking the decrease in protein arginine methyltransferase-6 expression.Moreover,when protein arginine methyltransferase-6 expression was downregulated in the dorsal root ganglion in mice without spared nerve injury,increased levels of phosphorylated extracellular signal-regulated kinases were observed in the ipsilateral dorsal horn,and the response to mechanical stimuli was enhanced.Mechanistically,protein arginine methyltransferase-6 appeared to contribute to spared nerve injury-induced neuropathic pain by regulating the expression of heterogeneous nuclear ribonucleoprotein-F.Additionally,protein arginine methyltransfe rase-6-mediated modulation of hete rogeneous nuclear ribonucleoprotein-F expression required amino atids 319 to 388,but not classical H3R2 methylation.These findings indicated that protein arginine methyltransferase-6 is a potential therapeutic target fo r the treatment of peripheral neuro pathic pain. 展开更多
关键词 dorsal root ganglion heterogeneous nuclear ribonucleoprotein F neuropathic pain protein arginine methyltransferase-6 sensory neurons
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Bidirectional regulation of the brain-gut-microbiota axis following traumatic brain injury
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作者 Xinyu You Lin Niu +4 位作者 Jiafeng Fu Shining Ge Jiangwei Shi Yanjun Zhang Pengwei Zhuang 《Neural Regeneration Research》 SCIE CAS 2025年第8期2153-2168,共16页
Traumatic brain injury is a prevalent disorder of the central nervous system.In addition to primary brain parenchymal damage,the enduring biological consequences of traumatic brain injury pose long-term risks for pati... Traumatic brain injury is a prevalent disorder of the central nervous system.In addition to primary brain parenchymal damage,the enduring biological consequences of traumatic brain injury pose long-term risks for patients with traumatic brain injury;however,the underlying pathogenesis remains unclear,and effective intervention methods are lacking.Intestinal dysfunction is a significant consequence of traumatic brain injury.Being the most densely innervated peripheral tissue in the body,the gut possesses multiple pathways for the establishment of a bidirectional“brain-gut axis”with the central nervous system.The gut harbors a vast microbial community,and alterations of the gut niche contribute to the progression of traumatic brain injury and its unfavorable prognosis through neuronal,hormonal,and immune pathways.A comprehensive understanding of microbiota-mediated peripheral neuroimmunomodulation mechanisms is needed to enhance treatment strategies for traumatic brain injury and its associated complications.We comprehensively reviewed alterations in the gut microecological environment following traumatic brain injury,with a specific focus on the complex biological processes of peripheral nerves,immunity,and microbes triggered by traumatic brain injury,encompassing autonomic dysfunction,neuroendocrine disturbances,peripheral immunosuppression,increased intestinal barrier permeability,compromised responses of sensory nerves to microorganisms,and potential effector nuclei in the central nervous system influenced by gut microbiota.Additionally,we reviewed the mechanisms underlying secondary biological injury and the dynamic pathological responses that occur following injury to enhance our current understanding of how peripheral pathways impact the outcome of patients with traumatic brain injury.This review aimed to propose a conceptual model for future risk assessment of central nervous system-related diseases while elucidating novel insights into the bidirectional effects of the“brain-gut-microbiota axis.” 展开更多
关键词 traumatic brain injury brain-gut-microbiome axis gut microbiota NEUROIMMUNE immunosuppression host defense vagal afferents bacterial infection dorsal root ganglia nociception neural circuitry
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Pulp health and calcific healing of a complicated crown–root fracture with additional root fracture in a maxillary incisor: A case report
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作者 Na Li Yue-Yue Ren +4 位作者 Ying Tang Qi Yang Tian-Tian Meng Song Li Jing Zhang 《World Journal of Clinical Cases》 SCIE 2025年第3期42-49,共8页
BACKGROUND Complicated crown–root fracture (CRF) involves severe injury to the crown, root,and pulp, and may be accompanied by multiple root fractures. The loss of a toothhas lifelong consequences for children and te... BACKGROUND Complicated crown–root fracture (CRF) involves severe injury to the crown, root,and pulp, and may be accompanied by multiple root fractures. The loss of a toothhas lifelong consequences for children and teenagers, but the maintenance of pulphealth and the calcific healing of multiple root fractures are rarely reported in theliterature.CASE SUMMARY This case reports healing of a permanent tooth with complicated crown–root andadditional root fractures, in which pulp health was maintained. A 10-year-old girlfell and fractured the root of her maxillary left central incisor at the cervical level.After the coronal fragment was repositioned, the tooth was splinted until thetooth was no longer mobile, 2 years later. Eight years after treatment, the toothhas remained asymptomatic with vital pulp and localized gingival overgrowth.Cone-beam computed tomography revealed not only calcified healing of the CRFbut also spontaneous healing in an additional undiagnosed root fracture. Thefracture line on the enamel could not be healed by hard tissue and formed agroove in the cervical crown. It was speculated that the groove was related to thelocalized gingival overgrowth.CONCLUSION This case provides a clinical perspective of the treatment of a tooth with acomplicated CRF and an additional root fracture. 展开更多
关键词 Complicated crown-root fracture Multiple root fracture Spontaneous healing Cone-beam computed tomography Long-term follow-up Case report
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ASYMPTOTIC ENUMERATIONS FOR ROOTED PLANAR MAPS AND ROOTED OUTERPLANAR MAPS
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作者 颜基义 刘彦佩 《Chinese Science Bulletin》 SCIE EI CAS 1991年第3期188-192,共5页
All maps we deal with in this note are rooted planar ones, which, in brief, are called maps. Most of terminologies here come from Refs. [1—3]. The purpose of this note is to determine the asymptotic enumerations base... All maps we deal with in this note are rooted planar ones, which, in brief, are called maps. Most of terminologies here come from Refs. [1—3]. The purpose of this note is to determine the asymptotic enumerations based on the enumerations in [1, 2]. Bender and Richmond gave a survey of the asymptotic enumeration. New asymptotic enumerations here can be considered as a complement and improvement of the survey. 展开更多
关键词 rooted PLANAR MAP rooted outerplanar map.
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ON FACE PARTITION OF ROOTED OUTERPLANAR MAPS
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作者 刘彦佩 《Chinese Science Bulletin》 SCIE EI CAS 1989年第5期365-369,共5页
A summation free formula for enumerating rooted nonseparable outerplanar maps with a face partition given is herein presented. As its corollaries, some summation free formulae for the bipartite and the simple cases ar... A summation free formula for enumerating rooted nonseparable outerplanar maps with a face partition given is herein presented. As its corollaries, some summation free formulae for the bipartite and the simple cases are also derived. Moreover, the formula for planted plane trees according to a given vertex partition is demonstrated in a new way. 展开更多
关键词 rooted MAP FACE PARTITION FUNCTIONAL EQUATION enumeration.
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On Real-rootedness of Independence Polynomials of Rooted Products of Graphs
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作者 Aria Ming-yue ZHU Bao-xuan ZHU 《Acta Mathematicae Applicatae Sinica》 SCIE CSCD 2023年第4期854-867,共14页
An independent set in a graph G is a set of pairwise non-adjacent vertices. The independence polynomial of G is the polynomial AΣx^(|A|), where the sum is over all independent sets A of G. In 1987, Alavi,Malde, Schwe... An independent set in a graph G is a set of pairwise non-adjacent vertices. The independence polynomial of G is the polynomial AΣx^(|A|), where the sum is over all independent sets A of G. In 1987, Alavi,Malde, Schwenk and Erd os conjectured that the independence polynomial of any tree or forest is unimodal.Although this unimodality conjecture has attracted many researchers’ attention, it is still open. Recently, Basit and Galvin even asked a much stronger question whether the independence polynomial of every tree is ordered log-concave. Note that if a polynomial has only negative real zeros then it is ordered log-concave and unimodal.In this paper, we observe real-rootedness of independence polynomials of rooted products of graphs. We find some trees whose rooted product preserves real-rootedness of independence polynomials. In consequence, starting from any graph whose independence polynomial has only real zeros, we can obtain an infinite family of graphs whose independence polynomials have only real zeros. In particular, applying it to trees or forests, we obtain that their independence polynomials are unimodal and ordered log-concave. 展开更多
关键词 independence polynomials UNIMODALITY real zeros rooted products claw-free graphs
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The Number of Rooted Circuit Boundary Maps
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作者 Yan XU Yan Pei LIU 《Acta Mathematica Sinica,English Series》 SCIE CSCD 2010年第9期1653-1666,共14页
In this article, the authors discuss two kinds of new planar maps: pan-fan maps and circuit boundary maps, and provide explicit expressions about their enumerating functions with different parameters. Meanwhile, two ... In this article, the authors discuss two kinds of new planar maps: pan-fan maps and circuit boundary maps, and provide explicit expressions about their enumerating functions with different parameters. Meanwhile, two explicit counting formulas for circuit cubic boundary maps with two parameters; the size and the valency of the root-face, are also extracted. 展开更多
关键词 rooted map enumerating function ENUMERATION circuit boundary maps
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