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From amalgamation to post-orogenic Rodinian rifting:Decoded by the Neoproterozoic Shenshan Group,South China
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作者 Hong-shuai Wu Yu-zhi Zhang +5 位作者 Xue Yang Jian-wen Yang Meng-yuan Li Xiao-qing Yu Cheng Wang Cheng-shi Gan 《China Geology》 2026年第1期102-119,I0001-I0014,共32页
The Shenshan Group provides important geological information which is vital in unraveling the amalgamation and subsequent rifting processes of South China.While conventional studies have asserted its formation in a su... The Shenshan Group provides important geological information which is vital in unraveling the amalgamation and subsequent rifting processes of South China.While conventional studies have asserted its formation in a subduction setting,the distinct investigation reveals the necessity for reassessment.To address this,the authors employ integrated methods encompassing petrological,zircon U-Pb geochronological,Lu-Hf isotopic and geochemical methods for sedimentary rocks from the upper Shenshan subgroup and Banxi Group.The geochemical results indicate that they were formed through the recycling deposition of intermediate-acidic igneous source material and experienced moderate chemical weathering.Additionally,both sedimentary sequences exhibit characteristics consistent with those formed in an intracontinental extensional rift setting since ca.810 Ma.The provenance analysis indicates that the upper Shenshan subgroup primarily originates from the Yangtze Domain,while the Banxi Group from both the Yangtze and Cathaysia domains.Synthesizing with previous studies,the Shenshan Group should be subdivided into the lower and upper subgroups which represent distinct tectonic backgrounds.The lower subgroup is inferred to have formed in an Early Neoproterozoic fore-arc setting,akin to the Zhoutan group.The upper subgroup corresponds to the Banxi Group,representing the Middle Neoproterozoic postorogenic rift setting,responding to the breakup of Rodinia. 展开更多
关键词 South China plate Subdivision of the Shenshan Group The upper Shenshan Subgroup Sedimentary rock Intermediate-acidic igneous source material post-orogenic rift setting MESO-NEOPROTEROZOIC Fore-arc environment Rodinian continental rifting Geological survey engineering
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Potential role of astrocyte on gamma-aminobutyric acid tone regulation during developmental period
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作者 Erva Ozkan Wuhyun Koh 《Neural Regeneration Research》 2026年第3期1118-1119,共2页
The early developmental period is a critical window during which brain cells mature and contribute to both brain development and later life functions.Gamma-aminobutyric acid(GABA),recognized as a major neurotransmitte... The early developmental period is a critical window during which brain cells mature and contribute to both brain development and later life functions.Gamma-aminobutyric acid(GABA),recognized as a major neurotransmitter,plays a crucial role in coordinating synapse formation,neuronal proliferation,and migration during this time. 展开更多
关键词 early developmental period developmental period brain cells neuronal proliferation synapse formation gamma aminobutyric acid ASTROCYTE GABA
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THE DYNAMICAL BEHAVIOR OF AN ALMOST PERIODIC SVEIR WARNING MODEL IN A PATCHY ENVIRONMENT
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作者 Binguo WANG Xiaomei MA Yashi WANG 《Acta Mathematica Scientia》 2026年第1期427-458,共32页
The outbreak of infectious diseases is the result of a combination of various factors,including season,the movement of individuals,non-pharmaceutical interventions(NPIs)and the effectiveness and availability of vaccin... The outbreak of infectious diseases is the result of a combination of various factors,including season,the movement of individuals,non-pharmaceutical interventions(NPIs)and the effectiveness and availability of vaccines.Taking these key elements into consideration,an almost periodic SVEIR warning model in the patch environment is here proposed.First,in terms of reproduction numbers,our results imply that if the effective reproduction numbers are R_(e)<1,then the disease dies out;if R_(e)>1,then the disease spreads and leads to local outbreaks.Second,the relationships between R_(e)and C_(s1),C_(a1)(see Section 2)are given by numerical simulations.The numerical results show that even if all people are vaccinated,NPIs are still needed because of the potentially low efficacy of vaccines.Furthermore,the numerical results suggest that NPIs and the strengthening of the effective rate of vaccination are essential in order to achieve herd immunity.Theories involving this model effectively explain the transmission mechanism of most infectious diseases,and provide a valuable theoretical basis for analyzing new infectious diseases in the future.Moreover,this model is helpful for the prevention and control of infectious diseases and the formulation of public health safety policies. 展开更多
关键词 SVEIR model almost periodicity reproduction ratio skew-product semiflow threshold dynamics
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Origin and Tectonic Implications of Post-Orogenic Lamprophyres in the Sulu Belt of China 被引量:5
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作者 Songjie Wang Lu Wang +1 位作者 Yue Ding Zhuocheng Wang 《Journal of Earth Science》 SCIE CAS CSCD 2020年第6期1200-1215,共16页
Lamprophyre dykes that crosscut different types of ultrahigh pressure(UHP)metamorphic rocks are widely distributed in the Triassic Sulu UHP orogenic belt.Although abundant studies have been performed on these dykes,th... Lamprophyre dykes that crosscut different types of ultrahigh pressure(UHP)metamorphic rocks are widely distributed in the Triassic Sulu UHP orogenic belt.Although abundant studies have been performed on these dykes,their origin and petrogenesis remain topics of controversy.This study presents the results of a detailed field-based study of petrology,whole-rock geochemistry and zircon U-Pb and Lu-Hf isotopes on lamprophyre dykes exposed in the central Sulu UHP zone,aiming at shedding lights on their petrogenesis and providing clues on the geological evolution of eastern continental China during the Cretaceous.The lamprophyres are typically porphyritic,with phenocrysts dominantly composed of amphibole and clinopyroxene set in a lamprophyric matrix.The dykes have moderate Si O2(47.70 wt.%–60.44 wt.%),variably high Mg O(2.58 wt.%–8.28 wt.%)and Fe2 O3 T(4.88 wt.%–9.26 wt.%)contents with high Mg#of 49–66.Geochemically,they have enriched light rare earth element(REE)and flat heavy REE patterns((La/Gd)N=5.14–10.56;(Dy/Yb)N=1.43–1.54)with negligible Eu anomalies(Eu/Eu*=0.83–1.10),and they show enrichment in large ion lithophile elements(e.g.,Ba and K)but depletion in high-field strength elements(e.g.,Nb,Ti and P).In-situ zircon U-Pb geochronology reveals that the lamprophyres have concordant ages of 120–115 Ma,demonstrating that the dykes emplaced in the Early Cretaceous.These zircons have?Hf(t)values ranging from-26.0 to-11.0.Inherited zircons that occur in the dykes are dated to be Neoproterozoic,in line with the protolith ages of their host(i.e.,the UHP rocks).An integration of these data allows us to propose that the lamprophyres were generated during the Cretaceous,by melting of subcontinental lithospheric mantle-derived metasomatite with enriched chemical compositions underneath the North China Craton.The metasomatite was formed mainly by peridotite-fluid/melt reactions,with the fluids/melts mainly liberated from subducted Yangtze continental crust during the Triassic.Regional extension,lithospheric thinning and mantle upwelling caused by rollback of the subducted paleoPacific plate is considered to account for the generation of the lamprophyres as well as the extensive arc-like magmatic rocks in eastern continental China during the Early Cretaceous. 展开更多
关键词 LAMPROPHYRE post-orogenic mafic magmatism crust-mantle interaction paleo-Pacific subduction Sulu orogenic belt
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番红砗磲生物钟基因Cryptochrome和Period克隆鉴定及光照相关性分析
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作者 杨文红 南祎晗 +4 位作者 李萌 刘春胜 杨毅 於锋 顾志峰 《渔业科学进展》 北大核心 2025年第4期153-167,共15页
生物钟是生物体适应地球周期性昼夜变化而演化出体内自持的计时机制,Cryptochrome和Period是生物钟的2个核心基因,其通过形成PER/CRY异二聚体调控生物体节律。本研究应用分子生物学和生物信息学技术对番红砗磲(Tridacna crocea)生物钟基... 生物钟是生物体适应地球周期性昼夜变化而演化出体内自持的计时机制,Cryptochrome和Period是生物钟的2个核心基因,其通过形成PER/CRY异二聚体调控生物体节律。本研究应用分子生物学和生物信息学技术对番红砗磲(Tridacna crocea)生物钟基因Cryptochrome和Period的编码区进行了克隆和特征分析,继而开展了其组织特异性和不同光照周期下的表达节律性研究。结果显示,Cryptochrome编码区碱基序列长1641 bp,编码546个氨基酸,理论等电点为6.08,分子量为62.98 kDa;Period编码区碱基序列长4386 bp,编码1461个氨基酸,理论等电点为6.14,分子量为164.99 kDa;Hdock互作模式研究结果显示,2个蛋白可形成异二聚体,结合能为–279.88 kcal/mol。组织表达分析显示,Cryptochrome和Period在7个组织中均有表达,其中,外外套膜、内外套膜、鳃和闭壳肌相对表达量较高(Cryptochrome在心脏中亦有较高表达量)。Cryptochrome和Period基因在外外套膜、内外套膜、鳃和闭壳肌中均昼夜变化,并呈现振荡表达的规律。在内、外外套膜中,Cryptochrome和Period基因分别在光照后1 h和光照前2 h表达量达到最高,且均随光照周期的推移(光照时间07:00~19:00推迟至09:00~21:00)而推移;在鳃组织中,正常光周期处理的Cryptochrome和Period基因均在光照前1 h表达量达到最高,当光照延迟2 h后,2个基因的最高表达时间推至光照后1 h;与之相反,闭壳肌中Cryptochrome和Period基因在08:00左右表达量最高,且未随光照延迟而发生变化。综上,本研究首次克隆获得番红砗磲2个关键生物钟基因Cryptochrome和Period,初步验证了这2个基因在主要组织表达的昼夜节律性,结果对揭示番红砗磲行为、生理节律和光照适应机制具有重要意义。 展开更多
关键词 番红砗磲 Cryptochrome和period 昼夜节律 表达规律
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ROLE OF POST-OROGENICEXTENSIONAL TECTONICS IN THE SUPERGIANT ANTIMONY MINERALIZATION IN CENTRAL HUNAN PROVINCE, SOUTH CHINA
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作者 Yi Jianbin Shan Yehua (Changsha Institute of Geotectonics,Academia Sinica, Changsha, 410013, China) 《Geotectonica et Metallogenia》 1995年第Z1期62-70,共9页
The Xikuangshan antimony deposit in central Hunan, South China, is the largest antimony deposit ever known in the world. The ore bodies are strictly confined to the footwalls of mafor high-angle normal faults which tr... The Xikuangshan antimony deposit in central Hunan, South China, is the largest antimony deposit ever known in the world. The ore bodies are strictly confined to the footwalls of mafor high-angle normal faults which transect the inclined folds in the flank;away from the fault planes,both the homogenization temperatures of inclusions in gangue minerals and the intensity of antimony mineralization decrease.These characteristics strongly demonstrate that the faults are used as the conduit for the metal-bearing fluid in mineralization.The normal faults,striking the NE to NNE,are interpreted to be generated by the postmgenic extension in the time from Cretaceous to Paleogene.Crustal or lithospheric thinning, directly resulting from regional extension inevitably increase the geothermal gradient, Which is likely to cause large-scale convection of underground water that may leach out and transport valuablemetals such as Sb from source rocks.Focussed discharge along the fault zones contributes to the formation of the supergiant antimony deposit in Xikuangshan under the appropriate sedimentary barrier. 展开更多
关键词 post-orogenic extension supergiant ANTIMONY MINERALIZATION central HUNAN SOUTH China
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Geochronological Significance of the Post-Orogenic Mafic-Ultramafic Rocks in the Hongqiling Area of Jilin Province, Northeast China
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作者 Zhang Guangliang Wu Fuyuan 《Earthquake Research in China》 2006年第2期216-224,共9页
Mafic-uitramafic complexes are widespread in Hongqiling in central Jiulin Province, NE China. The Hongqiling complex comprises pyroxenite, olivine websterite, lberzolite, gabbro and leucogabbro. Based on the latest ge... Mafic-uitramafic complexes are widespread in Hongqiling in central Jiulin Province, NE China. The Hongqiling complex comprises pyroxenite, olivine websterite, lberzolite, gabbro and leucogabbro. Based on the latest geochronological results, these intrusions yield a zircon U-Pb age of about 216 Ma, implying that they emplaced in the late Triassic period and that the mafic-uitramafic complexes are post-orogenic in origin. These ages are coeval with the emplacement of A-type granites in the area, but slightly younger than syn-orogenic granitic magmatism. The composition of the parent magma during the equilibration of the accumulated olivine crystallizing is basaltic with high MgO, and it comes from depleted or juvenile lithospheric mantle, according to the results of trace elements and Sr-Nd isotopes. Amount of crustal material contaminated the magmatic source, implying that the mafic-uitramafic rocks originate from the mixing product of crust- and mantle-derived magma. Therefore, the magmatic source was contaminated by an amount of crustal material, and the subsequent crystal fractionation resulted in the Cu-Ni mineralization. Dynamic analyses indicate that, after the collision of the North China Craton and Jiamusi Massif, the lithospheric delamination during post-orogeny resulted in the upwelling of asthenosphere and the intruding of the mass and underplating of the mantle-derived magma, which led to the formation of the primary mafic-uitramafic magma due to the mantle-derived magma and partial melting of the lower crust. This result suggests that the mafic-uitramafic complexes belong to a typically important magmatic suite that evolved during post-orogenic processes, and they were exposed as maficultramafic dyke swarms that existed in the post-orogenic extension environment. It also implies that the orogenic process finished ultimately in this regional geological setting. The widespread occurrence of mafic-uitramafic complexes in the Xing'an-Mongolia Orogenic Belt in NE China and in the Altay-Tianshan-Junggar Orogenic Belt in Northern Xinjiang indicates that mafic intrusions are an important magmatic suite that evolved during post-orogenic processes. Portions of this mafic magma could have underplated the lower crust, and served as a heat source for associated late-stage granitic magmas. 展开更多
关键词 Mafic-uitramafic complexes GEOCHRONOLOGY post-orogenic processes PETROGENESIS Hongqiling-Piaohechuan area
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Circadian disruption by simulated shift work aggravates periodontitis via orchestrating BMAL1 and GSDMD-mediated pyroptosis 被引量:2
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作者 Yazheng Wang Rui Li +6 位作者 Qingyuan Ye Dongdong Fei Xige Zhang Junling Huang Tingjie Liu Jinjin Wang Qintao Wang 《International Journal of Oral Science》 2025年第1期122-132,共11页
Approximately 20%to 30%of the global workforce is engaged in shift work.As a significant cause of circadian disruption,shift work is closely associated with an increased risk for periodontitis.Nevertheless,how shift w... Approximately 20%to 30%of the global workforce is engaged in shift work.As a significant cause of circadian disruption,shift work is closely associated with an increased risk for periodontitis.Nevertheless,how shift work-related circadian disruption functions in periodontitis remains unknown.Herein,we employed a simulated shift work model constructed by controlling the environmental light-dark cycles and revealed that shift work-related circadian disruption exacerbated the progression of experimental periodontitis.RNA sequencing and in vitro experiments indicated that downregulation of the core circadian protein brain and muscle ARNT-like protein 1(BMAL1)and activation of the Gasdermin D(GSDMD)-mediated pyroptosis were involved in the pathogenesis of that.Mechanically,BMAL1 regulated GSDMD-mediated pyroptosis by suppressing NOD-like receptor protein 3(NLRP3)inflammasome signaling through modulating nuclear receptor subfamily 1 group D member 1(NR1D1),and inhibiting Gsdmd transcription via directly binding to the E-box elements in its promoter.GSDMD-mediated pyroptosis accelerated periodontitis progression,whereas downregulated BMAL1 under circadian disruption further aggravated periodontal destruction by increasing GSDMD activity.And restoring the level of BMAL1 by circadian recovery and SR8278 injection alleviated simulated shift work-exacerbated periodontitis via lessening GSDMD-mediated pyroptosis.These findings provide new evidence and potential interventional targets for circadian disruption-accelerated periodontitis. 展开更多
关键词 BMAL1 NLRP3 period
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Enhancing angiogenesis and osseointegration through a double gyroid Ti6Al4V scaffold with triply periodic minimal surface 被引量:1
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作者 Hao Liu Hao Chen +9 位作者 Bin Sun Danyang Fan Aobo Zhang Hanqiang Liu Hexiang Wei Wenbo Yang Yongyue Li Peng Xia Qing Han Jincheng Wang 《Bio-Design and Manufacturing》 2025年第1期36-54,I0013-I0017,共24页
The pore structure of porous scaffolds plays a crucial role in bone repair.The prevalent bone implant structure in clinical practice is the traditional cubic structure.However,the traditional cubic structure exhibits ... The pore structure of porous scaffolds plays a crucial role in bone repair.The prevalent bone implant structure in clinical practice is the traditional cubic structure.However,the traditional cubic structure exhibits sharp edges and junctions that are not conducive to cell adhesion or growth.In this study,a double gyroid(DG)Ti6Al4V scaffold based on a triply periodic minimal surface(TPMS)structure was devised,and the osseointegration performance of DG structural scaffolds with varying porosities was investigated.Compression tests revealed that the elastic modulus and compressive strength of DG structural scaffolds were sufficient for orthopedic implants.In vitro cellular experiments demonstrated that the DG structure significantly enhanced cell proliferation,vascularization,and osteogenic differentiation compared to the cubic structure.The DG structure with 55%porosity exhibited the most favorable outcomes.In vivo experiments in rabbits further demonstrated that DG scaffolds could promote neovascularization and bone regeneration and maturation;those with 55%porosity performed best.Comparing the surface area,specific surface area per unit volume,and internal flow distribution characteristics of gyroid and DG structure scaffolds,the latter are more conducive to cell adhesion and growth within scaffolds.This study underscored the potential of DG scaffolds based on the TPMS structure in optimizing the pore structure design of titanium scaffolds,inducing angiogenesis,and advancing the clinical application of titanium scaffolds for repairing bone defects. 展开更多
关键词 Double gyroid Triply periodic minimal surface OSSEOINTEGRATION ANGIOGENESIS
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Symmetric Periodic Solution of Linear Periodic Matrix Equations via BCR Algorithm
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作者 MA Changfeng XIE Yajun 《数学进展》 北大核心 2025年第4期881-890,共10页
Analysis and design of linear periodic control systems are closely related to the periodic matrix equations.The biconjugate residual method(BCR for short)have been introduced by Vespucci and Broyden for efficiently so... Analysis and design of linear periodic control systems are closely related to the periodic matrix equations.The biconjugate residual method(BCR for short)have been introduced by Vespucci and Broyden for efficiently solving linear systems Aα=b.The objective of this paper is to provide one new iterative algorithm based on BCR method to find the symmetric periodic solutions of linear periodic matrix equations.This kind of periodic matrix equations has not been dealt with yet.This iterative method is guaranteed to converge in a finite number of steps in the absence of round-off errors.Some numerical results are performed to illustrate the efficiency and feasibility of new method. 展开更多
关键词 periodic matrix equation biconjugate residual method symmetric periodic solution convergence analysis
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Periodic Solutions for a Stochastic Stage-structure Predator-prey Model with Impulses
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作者 HOU Meiting QIU Xiaoling 《数学进展》 北大核心 2025年第6期1307-1318,共12页
A stochastic stage-structure predator-prey system with impulsive effect is investigated.First,we build the corresponding system without impulse in order to demonstrate the existence and uniqueness of the global positi... A stochastic stage-structure predator-prey system with impulsive effect is investigated.First,we build the corresponding system without impulse in order to demonstrate the existence and uniqueness of the global positive solution.Second,by selecting an appropriate Lyapunov function,we provide the sufficient condition for the existence of a positive T-periodic solution.Finally,numerical simulations illustrate our theoretical results,which show that the impulse or the white noises can result in the extinction of the predator in a certain condition. 展开更多
关键词 periodic solution stochastic noise IMPULSE
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Stochastic Periodic Solutions for Two Populations Game Models with Impulses
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作者 HOU Meiting QIU Xiaoling 《应用数学》 北大核心 2025年第2期453-467,共15页
The article studies the evolutionary dynamics of two-population two-strategy game models with and without impulses. First, the payment matrix is given and two evolutionary dynamics models are established by adding sto... The article studies the evolutionary dynamics of two-population two-strategy game models with and without impulses. First, the payment matrix is given and two evolutionary dynamics models are established by adding stochastic and impulse. For the stochastic model without impulses, the existence and uniqueness of solution, and the existence of positive periodic solutions are proved, and a sufficient condition for strategy extinction is given. For the stochastic model with impulses, the existence of positive periodic solutions is proved. Numerical results show that noise and impulses directly affect the model, but the periodicity of the model does not change. 展开更多
关键词 periodic solution Stochastic game IMPULSES Strategy extinct
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Insulin-induced severe thyrotoxic periodic paralysis:A case report
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作者 Yan-Li Wang Jian Li 《World Journal of Clinical Cases》 SCIE 2025年第7期46-51,共6页
BACKGROUND Thyrotoxic periodic paralysis(TPP)is an endocrine emergency caused by thyrotoxicosis,manifesting mainly as periodic myasthenia and hypokalemia,and posing a serious threat to the patient's health.Fatigue... BACKGROUND Thyrotoxic periodic paralysis(TPP)is an endocrine emergency caused by thyrotoxicosis,manifesting mainly as periodic myasthenia and hypokalemia,and posing a serious threat to the patient's health.Fatigue,strenuous exercise,alcohol abuse,high carbohydrate intake and insulin injections are common triggers of paralysis.This article reports a case of severe TPP induced by insulin injection,elucidates the characteristics and pathogenesis of the disease,analyses the risk factors for triggering TPP,and hopefully provides more clinical data for TPP patients.CASE SUMMARY A 38-year-old Asian man presented to the emergency department with a oneweek history of limb weakness and worsening half-day.His medical history included poorly controlled type 2 diabetes and he had been switched to Aspart50 a week earlier.He was alert and oriented with upper extremity strength grade 3 and lower extremity strength grade 1.Emergency department tests showed hypokalemia of 1.6 mmol/L.The paramedics administered 1.5 g of potassium intravenously,followed by 4.0 g orally.Weakness in the arms and legs improved.He was referred to endocrinology where he was diagnosed with Graves'disease,with suboptimal control and insulin injections possibly causing TPP.We stopped his insulin and he was discharged with a potassium level of 4.0 mmol/L.CONCLUSION Insulin is a trigger for TPP and should be avoided in patients with hyperthyroidism.Early recognition and treatment of TPP is crucial,especially in patients presenting with hypokalemic periodic paralysis. 展开更多
关键词 Thyrotoxic periodic paralysis Potassium metabolism disorders INSULIN Triggers of paralysis Case report
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Prediction Method of Polar Navigation Window Period Based on Risk Evaluation
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作者 JIANG Jia−qi SHI Gui−jie WANG De−yu 《船舶力学》 北大核心 2025年第6期986-999,共14页
With the increase of international trade activities and the gradual melting of the polar ice cap,the importance of the Arctic route for marine transportation has been emphasized.Prediction of the polar navigation wind... With the increase of international trade activities and the gradual melting of the polar ice cap,the importance of the Arctic route for marine transportation has been emphasized.Prediction of the polar navigation window period is crucial for navigating in the Arctic route,which is of great significance to the selection of the route and the optimization of navigation.This paper introduces the establishment of a risk index system,determination of risk index weight,establishment of a risk evaluation model,and prediction algorithm for the window period.In addition,data sources of both environmental factors and ship factors are introducted,and their shortcomings are analyzed,followed by introduction of various methods involved in window prediction and analysis of their advantages and disadvantages.The quantitative risk evaluation and window period algorithm can provide a reference for the research of polar navigation window period prediction. 展开更多
关键词 window period risk evaluation polar navigation risk index
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Periodic Traveling Wave Solutions of a Single Population Model with Advection and Distributed Delay
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作者 GUO Zilin YU Tao TANG Xiaosong 《应用数学》 北大核心 2025年第4期988-995,共8页
In this paper,we investigate the periodic traveling wave solutions problem for a single population model with advection and distributed delay.By the bifurcation analysis method,we can obtain periodic traveling wave so... In this paper,we investigate the periodic traveling wave solutions problem for a single population model with advection and distributed delay.By the bifurcation analysis method,we can obtain periodic traveling wave solutions for this model under the influence of advection term and distributed delay.The obtained results indicate that weak kernel and strong kernel can both deduce the existence of periodic traveling wave solutions.Finally,we apply the main results in this paper to Logistic model and Nicholson’s blowflies model. 展开更多
关键词 Single population model Advection Distributed delay periodic traveling wave solution
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Empirical relationship between significant wave period and wave energy period in the coastal waters of China
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作者 Yuhuan Xue Chuanjiang Huang +2 位作者 Gang Wang Dejun Dai Fangli Qiao 《Acta Oceanologica Sinica》 2025年第1期50-58,共9页
Significant wave period is an important parameter in coastal and offshore engineering design.Traditional spectral wave models do not directly calculate this parameter,which means that it needs to be estimated from the... Significant wave period is an important parameter in coastal and offshore engineering design.Traditional spectral wave models do not directly calculate this parameter,which means that it needs to be estimated from the spectral periods using empirical formulas.The wave energy period is one of the wave periods directly output by many wave models and is often used in studies of wave energy.This study investigated the relationship between significant wave period and wave energy period using wave data measured at three stations in the coastal waters of China.The observations recorded at these stations in the South China Sea,the East China Sea,and the Bohai Sea covered a wide range of surface wave conditions.Analysis indicated that the ratio of significant wave period to wave energy period is closely related to the Goda peakedness parameter of the wave spectra.Therefore,we proposed an empirical formula in which significant wave period is a function of wave energy period and the Goda peakedness parameter.Evaluation results showed that the performance of this formula is substantially better than that of fitting formulas that use constant coefficients. 展开更多
关键词 surface waves significant wave period wave energy period wave spectral parameter wave spectra
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The impact of aging on neutrophil functions and the contribution to periodontitis
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作者 Zi Wang Anish Saxena +3 位作者 Wenbo Yan Silvia M.Uriarte Rafael Siqueira Xin Li 《International Journal of Oral Science》 2025年第1期20-31,共12页
The increasing aging population and aging-associated diseases have become a global issue for decades.People over 65 show an increased prevalence and greater severity of periodontitis,which poses threats to overall hea... The increasing aging population and aging-associated diseases have become a global issue for decades.People over 65 show an increased prevalence and greater severity of periodontitis,which poses threats to overall health.Studies have demonstrated a significant association between aging and the dysfunction of neutrophils,critical cells in the early stages of periodontitis,and their crosstalk with macrophages and T and B lymphocytes to establish the periodontal lesion.Neutrophils differentiate and mature in the bone marrow before entering the circulation;during an infection,they are recruited to infected tissues guided by the signal from chemokines and cytokines to eliminate invading pathogens.Neutrophils are crucial in maintaining a balanced response between host and microbes to prevent periodontal diseases in periodontal tissues.The impacts of aging on neutrophils'chemotaxis,anti-microbial function,cell activation,and lifespan result in impaired neutrophil functions and excessive neutrophil activation,which could influence periodontitis course.We summarize the roles of neutrophils in periodontal diseases and the aging-related impacts on neutrophil functional responses.We also explore the underlying mechanisms that can contribute to periodontitis manifestation in aging.This review could help us better understand the pathogenesis of periodontitis,which could offer novel therapeutic targets for periodontitis. 展开更多
关键词 NEUTROPHIL period IMPAIRED
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Periodic modulation of adiabatic dynamics in non-reciprocal Landau-Zener systems
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作者 Rong Chang Sheng-Chang Li 《Chinese Physics B》 2025年第3期259-264,共6页
The control of adiabatic dynamics is essential for quantum manipulation.We investigate the effects of both periodic modulating field and linear sweeping field on adiabatic dynamics based on a non-reciprocal Landau-Zen... The control of adiabatic dynamics is essential for quantum manipulation.We investigate the effects of both periodic modulating field and linear sweeping field on adiabatic dynamics based on a non-reciprocal Landau-Zener model with periodic modulation.We obtain adiabatic phase diagrams in the(ω,δ)parameter space,where the adiabatic region is bounded by the modulating frequencyωgreater than a critical valueω_(c) and the non-reciprocal parameterδless than one.The results show that the adiabaticity of the system is not sensitive to the modulating amplitude.We find that the critical modulating frequency can be expressed as a power function of the modulating period number or the sweeping rate.Our findings suggest that one can change the adiabatic region or improve the adiabaticity by adjusting the parameters of both the modulating and the sweeping fields,which provides an effective means to flexibly control the adiabatic dynamics of non-reciprocal systems. 展开更多
关键词 ADIABATICITY non-reciprocity Landau-Zener tunneling periodic modulation
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Temperature Characteristics and Temperature Estimation with Different Return Periods in Huailai County
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作者 Yue LI Riyuan HAO +1 位作者 Lulu WANG Jianyong LIU 《Meteorological and Environmental Research》 2025年第4期1-5,8,共6页
Huailai County in Zhangjiakou was taken as the research area.Based on daily temperature data from 1992 to 2021,various methods were used to analyze the characteristics of extreme temperature changes in the region and ... Huailai County in Zhangjiakou was taken as the research area.Based on daily temperature data from 1992 to 2021,various methods were used to analyze the characteristics of extreme temperature changes in the region and estimate extreme temperature values for different return periods.The results showed that from 1992 to 2021,both the annual average maximum and minimum temperatures in Huailai County exhibited a slight downward trend,with continuous low temperatures from 2010 to 2012;the annual average extreme maximum temperature slightly decreased,reaching a peak in 2010,with July being the concentrated period of extreme high temperatures;the extreme minimum temperature&quot;continuously cooled down"with multiple occurrences of low temperatures in the past decade and a decrease in the number of high temperature days.The estimation of return periods based on the Gumbel distribution indicates that the temperature values for different return periods vary between the highest and lowest temperature months,and the longer the return period,the more significant the extreme temperature values and the larger the standard deviation.The research can provide a basis for local agricultural development. 展开更多
关键词 Extreme temperature Variation characteristics Return period
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Are there sensitive periods for physical activity to influence the development of executive function in children?
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作者 Joseph M.Northey Lauren B.Raine Charles H.Hillman 《Journal of Sport and Health Science》 2025年第3期120-127,共8页
Executive functions emerge throughout childhood and shape multiple cognitive and behavioral outcomes across the lifespan.Given the importance of these functions,there is considerable interest in understanding the role... Executive functions emerge throughout childhood and shape multiple cognitive and behavioral outcomes across the lifespan.Given the importance of these functions,there is considerable interest in understanding the role of environmental enrichment to support their development.The past 20 years have seen the emergence of a body of evidence around the beneficial effects of engaging in physical activity for executive functioning in children.Despite this,there are still unanswered questions,particularly about the confounding effects of the timing and dose of exercise-based interventions.During development,sensitive periods with heightened neural plasticity and sensitivity to environmental influences can offer an optimal time to introduce enrichment interventions.As such,sensitive periods for executive function could indicate an ideal time to introduce physical activity or be a potential confounder to study results if not considered.This narrative review discusses the potential presence of sensitive periods in preadolescent development where physical activity has greater benefits for executive function.Initially,we briefly review the largely parallel fields investigating the presence of sensitive periods for executive function and the effects of physical activity on executive function outcomes.We then bring together these 2 concepts to discuss the theoretical basis for developmentally sensitive periods during which children may be particularly amenable to physical activity-based interventions and offer potential ways forward to investigate this phenomenon.We hope this review will attract researchers to collaborate in the area and extend our current understanding of the development of executive functions as well as interventions like physical activity. 展开更多
关键词 EXERCISE Working memory Cognitive flexibility INHIBITION Critical periods
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