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HOMOGENIZATION,SYMMETRY,AND PERIODIZATION IN DIFFUSIVE RANDOM MEDIA
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作者 Alen Alexanderian Muruhan Rathinam Rouben Rostamian 《Acta Mathematica Scientia》 SCIE CSCD 2012年第1期129-154,共26页
We present a systematic study of homogenization of diffusion in random me- dia with emphasis on tile-based random microstructures. We give detailed examples of several such media starting from their physical descripti... We present a systematic study of homogenization of diffusion in random me- dia with emphasis on tile-based random microstructures. We give detailed examples of several such media starting from their physical descriptions, then construct the associated probability spaces and verify their ergodicity. After a discussion of material symmetries of random media, we derive criteria for the isotropy of the homogenized limits in tile-based structures. ~rthermore, we study the periodization Mgorithm for the numerical approxi- mation of the homogenized diffusion tensor and study the algorithm's rate of convergence. For one dimensional tile-based media, we prove a central limit result, giving a concrete rate of convergence for periodization. We also provide numerical evidence for a similar central limit behavior in the case of two dimensional tile-based structures. 展开更多
关键词 HOMOGENIZATION periodization random media ergodic dynamical systems material symmetry ISOTROPY
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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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Circadian disruption by simulated shift work aggravates periodontitis via orchestrating BMAL1 and GSDMD-mediated pyroptosis 被引量:1
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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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New Features and New Challenges of U.S.-Europe Relations Under Trump 2.0 被引量:1
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作者 Zhao Huaipu 《Contemporary World》 2025年第3期47-52,共6页
During Donald Trump’s first term,the“Trump Shock”brought world politics into an era of uncertainties and pulled the transatlantic alliance down to its lowest point in history.The Trump 2.0 tsunami brewed by the 202... During Donald Trump’s first term,the“Trump Shock”brought world politics into an era of uncertainties and pulled the transatlantic alliance down to its lowest point in history.The Trump 2.0 tsunami brewed by the 2024 presidential election of the United States has plunged the U.S.-Europe relations into more gloomy waters,ushering in a more complex and turbulent period of adjustment. 展开更多
关键词 new features turbulent period Trump U S Europe relations presidential election new challenges UNCERTAINTIES transatlantic alliance
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Hierarchical detection and tracking for moving targets in underwater wireless sensor networks 被引量:1
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作者 Yudong Li Hongcheng Zhuang +2 位作者 Long Xu Shengquan Li Haibo Lu 《Digital Communications and Networks》 2025年第2期556-562,共7页
It is difficult to improve both energy consumption and detection accuracy simultaneously,and even to obtain the trade-off between them,when detecting and tracking moving targets,especially for Underwater Wireless Sens... It is difficult to improve both energy consumption and detection accuracy simultaneously,and even to obtain the trade-off between them,when detecting and tracking moving targets,especially for Underwater Wireless Sensor Networks(UWSNs).To this end,this paper investigates the relationship between the Degree of Target Change(DoTC)and the detection period,as well as the impact of individual nodes.A Hierarchical Detection and Tracking Approach(HDTA)is proposed.Firstly,the network detection period is determined according to DoTC,which reflects the variation of target motion.Secondly,during the network detection period,each detection node calculates its own node detection period based on the detection mutual information.Taking DoTC as pheromone,an ant colony algorithm is proposed to adaptively adjust the network detection period.The simulation results show that the proposed HDTA with the optimizations of network level and node level significantly improves the detection accuracy by 25%and the network energy consumption by 10%simultaneously,compared to the traditional adaptive period detection schemes. 展开更多
关键词 Underwater wireless sensor networks The degree of target change Mutual information PHEROMONE Adaptive period
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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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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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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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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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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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Comparison of complication rates after early and late closure of loop ileostomies:A retrospective cohort study
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作者 PırıltıÖzcan Özgül Düzgün 《World Journal of Gastrointestinal Surgery》 2025年第8期124-132,共9页
BACKGROUND In the treatment of rectal cancer,a temporary loop ileostomy(TLI)is created after low anterior resection to protect bowel function in the postoperative period.Dehydration and kidney failure are significant ... BACKGROUND In the treatment of rectal cancer,a temporary loop ileostomy(TLI)is created after low anterior resection to protect bowel function in the postoperative period.Dehydration and kidney failure are significant potential complications in loop ileostomies.Compared to late closure(3-6 months),early closure(10-14 days)of the TLI may facilitate faster patient recovery and shorter hospital stays.AIM To compare early and late closure of TLIs and demonstrate that early stoma closure can be performed without increasing morbidity.METHODS This study included patients who underwent TLI for rectal cancer,with data collected prospectively between June 2016 and October 2024 and analyzed retrospectively.Patients whose stomas were closed in the late period(3-6 months)between June 2016 and October 2022(group A)were compared with those who underwent early closure(10-14 days)between October 2022 and 2024(group B),with the primary outcome being complication rate and the secondary outcome being quality of life.RESULTS A total of 270 TLIs were created(70.9%).Of these,120(44.4%)were closed in the late period(group A),and 150(55.6%)were closed in the early period(group B).There was no statistically significant difference between group A and group B in terms of demographic and clinicopathological characteristics(P>0.05).Perioperative(anesthesia management,operative time,blood loss,surgical technique)and postoperative findings(anastomotic leak,infection)were similar between the two groups and were not statistically significant(P>0.05).There were no statistically significant differences in complication rates as the primary outcome between the two groups.Quality of life as a secondary outcome was significantly higher in the early closure group(P<0.05).CONCLUSION No statistically significant difference was found between early and late loop ileostomy closure in terms of perioperative and postoperative morbidity.Early closure accelerated patients’psychological and social recovery. 展开更多
关键词 Rectum cancer Loop ileostomy Early period Late period Complication rates
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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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Long Term Variability of Extreme Sea Surface Temperature in the Gulf of Tonkin, China
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作者 Yichun Lin Adekunle Osinowo 《Journal of Environmental & Earth Sciences》 2025年第1期274-291,共18页
Till date,no study on trends in extreme sea surface temperature(SST)for different return periods has been done over the Gulf of Tonkin(GoT).Based on a 84-year(1940–2023)ERA5 Reanalysis data sets,this study for the fi... Till date,no study on trends in extreme sea surface temperature(SST)for different return periods has been done over the Gulf of Tonkin(GoT).Based on a 84-year(1940–2023)ERA5 Reanalysis data sets,this study for the first time,examined the spatio-temporal pattern in extreme SST for different return periods.Findings showed that more significant moderate to fast warming trends(0.1–0.16°C per decade(dec-1))only existed for the 2 year return period.Temporal trends in the 99th percentile SST are insignificant for all return periods.By using the linear regression method,the variability in extreme SST was obtained.Results showed that moderate warming trends dominated a large portion of GoT.Stronger trends,up to 0.018°C yr-1 are noticed near Guangdong,Haikou and southern Sanya in south China.Extreme SST exhibited a slow warming trend of 0.008°C per year(yr-1)all through the study years.The SST is most stable in most waters in the southern GoT and few waters surrounding Dongfang.Temporal warming rates of SST revealed that 1940–1958,1976–1994 and 2003–2012 were years of more coastal upwelling and could affect aquatic lives.The strongest warming rate of 0.07°C dec-1 occurred during 1994–2003.The GoT appeared warmer during spring.Spatial decadal variability of SST revealed that moderate warming trends occurred in few regions in the southern GoT and in larger portion of the central and northern GoT.The rise in SST between 1980 and 2020 in the GoT is not limited to increased anthropogenic activities. 展开更多
关键词 SIGNIFICANT TRENDS Return Periods SPATIO-TEMPORAL Decade Index
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An Improved Repetitive-Control System Using a Complex-Coefficient Filter
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作者 Qicheng Mei Jinhua She +1 位作者 Fei Long Yanjun Shen 《IEEE/CAA Journal of Automatica Sinica》 2025年第1期282-284,共3页
Dear Editor,This letter presents an improved repetitive controller(IRC) that uses a complex-coefficient filter to enhance the tracking performance of a system for periodic signals. Compared with the low-pass filter us... Dear Editor,This letter presents an improved repetitive controller(IRC) that uses a complex-coefficient filter to enhance the tracking performance of a system for periodic signals. Compared with the low-pass filter used in the conventional repetitive controller(CRC), the complex-coefficient filter causes less change in the phase and amplitude of a signal at the frequencies of the periodic signal, especially at the fundamental frequency, when the two filters have the same cutofffrequency. 展开更多
关键词 improved repetitive controller irc periodic signals repetitive control system complex coefficient filter tracking performance conventional repetitive controller crc periodic signal enhance tracking performance
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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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Development characteristics and quantitative analysis of cracks in root-soil complex during different growth periods under dry-wet cycles
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作者 Zhengjun Mao Xu Ma +3 位作者 Mimi Geng Munan Wang Guangsheng Gao Yanshan Tian 《Biogeotechnics》 2025年第1期63-71,共9页
Repeated wet swelling and dry shrinkage of soil leads to the gradual occurrence of cracks and the formation of a complex fracture network.In order to study the development characteristics and quantitative analysis of ... Repeated wet swelling and dry shrinkage of soil leads to the gradual occurrence of cracks and the formation of a complex fracture network.In order to study the development characteristics and quantitative analysis of cracks in root-soil complex in different growth periods under dry-wet cycles,the alfalfa root-loess complex was in-vestigated during different growth periods under different dry-wet cycles,and a dry-wet cycle experiment was conducted.The crack rate,relative area,average width,total length,and the cracks fractal dimension in the root-soil complex were extracted;the crack development characteristics of plain soil were analyzed under the PG-DwC(dry-wet cycle caused by plant water management during plant growth period),as well as the crack development characteristics of root-soil complex under PG-DWC and EC-DWC(the dry-wet cycles caused by extreme natural conditions such as continuous rain);the effects of plant roots and dry-wet cycles on soil cracks were discussed.The results showed that the average crack width,crack rate,relative crack area,and total crack length of the alfalfa root-loess complex were higher than those of the plain soil during PG-DWC.The result indicated that compared with plain soil during PG-DWC,the presence of plant roots in alfalfa root-soil complex in the same growth period promoted the cracks development to some extent.The alfalfa root-soil complex crack parameters during different growth periods were relatively stable during PG-DWC(O dry-wet cycle).During EC-DWC(1,3,and 5 dry-wet cycles),the alfalfa root-loess complex crack parameters increased with the number of dry-wet cycles during different growth periods.Unlike PG-DWC,the EC-DWC accelerated crack development,and the degree of crack development increased with the number of dry-wet cycles.The existence of plant roots promoted crack development and expansion in the root-soil complex to a certain extent,and the dry-wet cycle certainly promoted crack development and expansion in the root-soil complex.This result contradicts the im-provement in the root-soil complex's macro-mechanical properties during plant growth,due to differences in the mechanical properties of roots and soil.The research results will provide reference for the root soil complex crack development law and the design of slope protection by vegetation. 展开更多
关键词 Dry-wet cycle Root-soil complex CRACK LOESS ALFALFA Growth period
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Integrated single-cell transcriptomic map of pig kidney cells across various periods and anatomical sites
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作者 Tian-Xiong Yao Na Li Lu-Sheng Huang 《Zoological Research》 2025年第2期469-482,共14页
The kidney is essential for maintaining fluid,electrolyte,and metabolite homeostasis,and for regulating blood pressure.The pig serves as a valuable biomedical model for human renal physiology,offering insights across ... The kidney is essential for maintaining fluid,electrolyte,and metabolite homeostasis,and for regulating blood pressure.The pig serves as a valuable biomedical model for human renal physiology,offering insights across different physiological states.In this study,single-cell RNA sequencing was used to profile 138469 cells from 12 pig kidney samples collected during the embryonic(E),fattening(F),and pregnancy(P)periods,identifying 29 cell types.Proximal tubule(PT)cells exhibited elevated expression of metabolism-related transcription factors(TFs),including GPD1,ACAA1,and AGMAT,with validation across multiple individuals,periods,and species.Fluorescence homologous double-labeling of paraffin sections further confirmed the expression of ACAA1 and AGMAT in PT cells.Comparative analysis of pig and human kidneys revealed a high degree of similarity among corresponding cell types.Analysis of cell-type heterogeneity highlighted the diversity of thick ascending limb(TAL)cells,identifying a TAL subpopulation related to immune function.Additionally,the functional heterogeneity of kidney-resident macrophages(KRM)was explored across different anatomical sites.In the renal medulla,KRM were implicated in phagocytosis and leukocyte activation,whereas in the renal pelvis,they functioned as ligands,recruiting neutrophils with bactericidal activity to the renal pelvis to combat urinary tract infections. 展开更多
关键词 PIG Kidney Single-cell RNA sequencing PERIODS Anatomical sites
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Research on the rapid diagnosis method for hunting of high-speed trains
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作者 Wanru Xie Yixin Zhao +3 位作者 Gang Zhao Fei Yang Zilong Wei Jinzhao Liu 《Railway Sciences》 2025年第1期1-21,共21页
Purpose–High-speed turnouts are more complex in structure and thus may cause abnormal vibration of highspeed train car body,affecting driving safety and passenger riding experience.Therefore,it is necessary to analyz... Purpose–High-speed turnouts are more complex in structure and thus may cause abnormal vibration of highspeed train car body,affecting driving safety and passenger riding experience.Therefore,it is necessary to analyze the data characteristics of continuous hunting of high-speed trains passing through turnouts and propose a diagnostic method for engineering applications.Design/methodology/approach–First,Complete Ensemble Empirical Mode Decomposition with Adaptive Noise(CEEMDAN)is performed to determine the first characteristic component of the car body’s lateral acceleration.Then,the Short-Time Fourier Transform(STFT)is performed to calculate the marginal spectra.Finally,the presence of a continuous hunting problem is determined based on the results of the comparison calculations and diagnostic thresholds.To improve computational efficiency,permutation entropy(PE)is used as a fast indicator to identify turnouts with potential problems.Findings–Under continuous hunting conditions,the PE is less than 0.90;the ratio of the maximum peak value of the signal component to the original signal peak value exceeded 0.7,and there is an energy band in the STFT time-frequency map,which corresponds to a frequency distribution range of 1–2 Hz.Originality/value–The research results have revealed the lateral vibration characteristics of the high-speed train’s car body during continuous hunting when passing through turnouts.On this basis,an effective diagnostic method has been proposed.With a focus on practical engineering applications,a rapid screening index for identifying potential issues has been proposed,significantly enhancing the efficiency of diagnostic processes. 展开更多
关键词 High-speed railway Periodic hunting Rapid diagnosis CEEMDAN STFT Permutation entropy
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Efficacy of Descending Aortic Retrograde Flow Area to Forward Flow Area Ratio on Echocardiography in Perioperative Management after Blalock-Thomas-Taussig Shunt
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作者 Kentaro Kogawa Reiji Ito +1 位作者 Daishi Hirano Kenji Hoshino 《Congenital Heart Disease》 2025年第4期451-461,共11页
Objective:To investigate the usefulness of the descending aortic retrograde flow area to forward flow area(dAO RF)ratio using echocardiography in managing pulmonary blood flow during the perioperative period following... Objective:To investigate the usefulness of the descending aortic retrograde flow area to forward flow area(dAO RF)ratio using echocardiography in managing pulmonary blood flow during the perioperative period following Blalock-Thomas-Taussig shunt(BTTS)surgery.Methods:This retrospective study analyzed patient characteristics,surgical procedures,and perioperative courses.The dAO RF ratio was measured upon admission to the pediatric intensive care unit(PICU)and 12,24,48,and 72 h post-surgery.Blood pressure,percutaneous oxygen saturation,arterial blood gas values,and lactate levels were measured at the same time as the dAO RF ratio.Results:Seventy-one cases were analyzed.Excessive and low pulmonary blood flow occurred in 17 and two patients,respectively.Four patients required resuscitation within 72 h post-surgery,due to excessive pulmonary blood flow.No deaths occurred within 72 h.The dAO RF ratio was significantly higher in patients with excessive pulmonary blood flow at PICU admission and at its maximum(p=0.049 and p<0.01,respectively).The maximum dAO RF ratio was significantly correlated with lactate levels when measured concurrently;however,there was clinical variability in the resuscitation cases.The dAO RF ratio cutoff of 0.61 was highly accurate(area under the receiver operating characteristic curve:0.91[95%confidence interval:0.82-1.00]),sensitive(82.4%),and specific(94.4%)for detecting excessive pulmonary blood flow.Conclusions:Measuring the dAO RF ratio postoperatively can prevent deterioration in patients with BTTS by accurately detecting excessive pulmonary blood flow,offering a minimally invasive and accurate assessment of perioperative pathophysiology. 展开更多
关键词 Blalock-Thomas-Taussig shunt AORTA THORACIC ECHOCARDIOGRAPHY pulmonary circulation perioperative period
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