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Effort minimization:A permanent,dynamic,and surmountable influence on physical activity
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作者 Silvio Maltagliati Layan Fessler +7 位作者 Qian Yu Zhihao Zhang Yanxia Chen Olivier Dupuy Ryan SFalck Neville Owen Liye Zou Boris Cheval 《Journal of Sport and Health Science》 2025年第4期43-47,共5页
Today, most people know that physical activity(PA) is beneficial for their health ^(1,2)and aspire to engage in regular PA.^(3,4)However, despite their awareness of the importance of PA, it is evident that the transit... Today, most people know that physical activity(PA) is beneficial for their health ^(1,2)and aspire to engage in regular PA.^(3,4)However, despite their awareness of the importance of PA, it is evident that the transition from intention to action is challenging-a situation that has important public health implications. According to the World Health Organization,^(5)1 person dies every 6 s worldwide from causes related to physical inactivity, which underscores the urgency of addressing this situation. 展开更多
关键词 World Health Organization physical activity pa effort minimization intention action public health physical inactivity physical activity
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Flexible Sensors for Battery Health Monitoring
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作者 Xin Wang Haiyan Zhang +11 位作者 Xinyi Qi Sheng Chen Zekai Huang Jinwei Zhao Yihang Wang Dezhi Wu Gaofeng Zheng Chenyang Xue Jianlin Zhou Hailong Wang Zongyou Yin Libo Gao 《Nano-Micro Letters》 2026年第5期336-370,共35页
With the widespread application of lithium batteries in electric vehicles and energy storage systems,battery-related safety and reliability issues have become increasingly prominent.Conventional monitoring methods oft... With the widespread application of lithium batteries in electric vehicles and energy storage systems,battery-related safety and reliability issues have become increasingly prominent.Conventional monitoring methods often struggle to address dynamic changes under complex operando.In recent years,flexible sensing technology has emerged as a promising solution for battery health monitoring due to its high adaptability and conformability to complex structures.Meanwhile,empowered by artificial intelligence(AI)for data analysis,the collected data enables efficient and accurate state assessment,offering robust support for accident prevention.Against this background,this paper first explores the integrated applications of flexible sensors in battery health monitoring and their unique advantages in addressing complex battery operating conditions,while analyzing the potential of AI in battery state analysis.Subsequently,it systematically reviews mainstream flexible sensing technologies(e.g.,film sensors,thermocouples,and optical fiber sensors),elucidating their mechanisms for revealing intricate internal battery processes during operation.Finally,the paper discusses AI’s role in enhancing monitoring efficiency and accuracy,and envisions future research directions and application prospects.This work aims to provide technical references for the battery health monitoring field as well as promote the application of flexible sensing technologies in improving battery system safety and reliability. 展开更多
关键词 Lithium battery Battery health monitoring Flexible sensing technology SAFETY Artificial intelligence
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A Perspective on Global Dimming and Brightening Worldwide and in China
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作者 Martin WILD Yawen WANG +1 位作者 Kaicun WANG Su YANG 《Advances in Atmospheric Sciences》 2026年第2期281-294,共14页
Worldwide radiation records suggest that the amount of sunlight received at the Earth's surface(surface solar radiation, SSR) has not been stable over the years, but underwent significant decadal variations, popul... Worldwide radiation records suggest that the amount of sunlight received at the Earth's surface(surface solar radiation, SSR) has not been stable over the years, but underwent significant decadal variations, popularly also known as “global dimming and brightening”. These variations have been particularly evident in China, where the SSR substantially declined from the 1960s to the 1990s(dimming), with indications for a trend reversal in the 2000s and a slight recovery(brightening) in recent years. This perspective/review paper will discuss recent updates and remaining challenges regarding our knowledge of the magnitudes, causes, and implications of these variations in SSR worldwide, with a particular emphasis on the developments in China. 展开更多
关键词 global dimming and brightening surface solar radiation AEROSOLS air pollution climate change
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Experimental Verification of Intrinsic Pressure Framework in an Activity Landscape
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作者 Zihao Sun Longfei Li +6 位作者 Chuyun Wang Jing Wang Huaicheng Chen Gao Wang Fangfu Ye Liyu Liu Mingcheng Yang 《Chinese Physics Letters》 2026年第1期322-326,共5页
The intrinsic pressure framework,which treats self-propelling force as an external force,provides a convenient and consistent description of mechanical equilibrium in active matter.However,direct experimental evidence... The intrinsic pressure framework,which treats self-propelling force as an external force,provides a convenient and consistent description of mechanical equilibrium in active matter.However,direct experimental evidence is still lacking.To validate this framework,here we employ a programmable robotic platform,where a single light-controlled wheeled robot travels in an activity landscape.Our experiments quantitatively demonstrate that the intrinsic pressure difference across the activity interface is balanced by the emerged polarization force.This result unambiguously confirms the theoretical predictions,thus validating the intrinsic pressure framework and laying the experimental foundation for the intrinsic pressure-based mechanical description of dry active matter. 展开更多
关键词 intrinsic pressure framework activity landscape intrinsic pressure difference robotic platform programmable robotic platformwhere self propelling force polarization force mechanical equilibrium
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The Physical Significance of the Synthetic Running Correlation Coefficient and Its Applications in Oceanic and Atmospheric Studies 被引量:6
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作者 ZHAO Jinping CAO Yong WANG Xin 《Journal of Ocean University of China》 SCIE CAS CSCD 2018年第3期451-460,共10页
In order to study the temporal variations of correlations between two time series,a running correlation coefficient(RCC)could be used.An RCC is calculated for a given time window,and the window is then moved sequentia... In order to study the temporal variations of correlations between two time series,a running correlation coefficient(RCC)could be used.An RCC is calculated for a given time window,and the window is then moved sequentially through time.The current calculation method for RCCs is based on the general definition of the Pearson product-moment correlation coefficient,calculated with the data within the time window,which we call the local running correlation coefficient(LRCC).The LRCC is calculated via the two anomalies corresponding to the two local means,meanwhile,the local means also vary.It is cleared up that the LRCC reflects only the correlation between the two anomalies within the time window but fails to exhibit the contributions of the two varying means.To address this problem,two unchanged means obtained from all available data are adopted to calculate an RCC,which is called the synthetic running correlation coefficient(SRCC).When the anomaly variations are dominant,the two RCCs are similar.However,when the variations of the means are dominant,the difference between the two RCCs becomes obvious.The SRCC reflects the correlations of both the anomaly variations and the variations of the means.Therefore,the SRCCs from different time points are intercomparable.A criterion for the superiority of the RCC algorithm is that the average value of the RCC should be close to the global correlation coefficient calculated using all data.The SRCC always meets this criterion,while the LRCC sometimes fails.Therefore,the SRCC is better than the LRCC for running correlations.We suggest using the SRCC to calculate the RCCs. 展开更多
关键词 running correlation coefficient time window ANOMALY varying mean synthetic running correlation coefficient
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Physical processes causing the formation of hypoxia off the Changjiang estuary after Typhoon Chan-hom, 2015 被引量:6
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作者 GUO Yaru RONG Zengrui +3 位作者 LI Bo XU Zhao LI Pixue LI Xiaodan 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2019年第1期1-17,共17页
Severe hypoxia was observed in the submarine canyon to the east of the Changjiang estuary in July 14, 2015, two days after typhoon Chan-hom. The oxygen concentration reached as low as 2.0 mg/L and occupied a water col... Severe hypoxia was observed in the submarine canyon to the east of the Changjiang estuary in July 14, 2015, two days after typhoon Chan-hom. The oxygen concentration reached as low as 2.0 mg/L and occupied a water column of about 25 m. A ROMS model was con?gured to explore the underlying physical processes causing the formation of hypoxia. Chan-hom passed through the Changjiang estuary during the neap tide. The strati?cation was completely destroyed in the shallow nearshore region when typhoon passing. However, it was maintained in the deep canyon, though the surface mixed layer was largely deepened. The residual water in the deep canyon is considered to be the possible source of the later hypoxia. After Chan-hom departure, not only the low salinity plume water spread further of fshore, but also the sea surface temperature(SST) rewarmed quickly. Both changes helped strengthen the strati?cation and facilitate the formation of hypoxia. It was found that the surface heat ?ux, especially the solar short wave radiation dominated the surface re-warming, the of fshore advection of the warmer Changjiang Diluted Water(CDW) also played a role. In addition to the residual water in the deep canyon, the Taiwan Warm Current(TWC) was found to ?ow into the deep canyon pre-and soon post-Chan-hom, which was considered to be the original source of the hypoxia water. 展开更多
关键词 HYPOXIA CHANGJIANG estuary deep CANYON vertical mixing advection heat fl ux
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Influence of the Physical Environment on the Migration and Distribution of Nibea albiflora in the Yellow Sea 被引量:1
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作者 ZHU Xianye WU Kejian WU Lunyu 《Journal of Ocean University of China》 SCIE CAS CSCD 2017年第1期87-92,共6页
This study investigates the migration and distribution of the warm-temperate fish Nibea albiflora. Their spawning migration and wintering migratory routes within in the Yellow Sea are described in detail. Considering ... This study investigates the migration and distribution of the warm-temperate fish Nibea albiflora. Their spawning migration and wintering migratory routes within in the Yellow Sea are described in detail. Considering the main physical features and environment of the Yellow Sea, it appears to be have one wintering ground and three migratory routes from the wintering ground to the spawning grounds. The fish begin to migrate from the wintering ground to the spawning grounds in the northwest region of the Yellow Sea in late March. The Yellow Sea has three spawning grounds. The first is located near the Yalu River on the Liaodong Peninsula and the second one is located in Rushan Bay of Shandong Peninsula. The third spawning ground is located in Haizhou Bay in the southern region of the Yellow Sea. This study found that the temperature of the Yellow Sea influences the migration of N. albiflora, and that the migratory routes coincide with the thermal fronts in the sea. Nutrients for juvenile fish are taken from the coastal upwelling area. Chlorophyll is a good environmental indicator of phytoplankton biomass and thereby provides the status of biological resources. Different types of sediment in near-shore zones are also of practical significance for the growth of fish. The study of the effects of marine environments on the migration of various fishes is not only significant to the fishing industry, but can also provide a scientific basis for the understanding of the ecological implications of the relevant physical processes. 展开更多
关键词 Nibea albiflora MIGRATION TEMPERATURE CHLOROPHYLL SEDIMENTS
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Laboratory Experiment on Wave Induced Turbulence 被引量:1
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作者 WEI Lai GUAN Changlong TROITSKAYA Yuliya 《Journal of Ocean University of China》 SCIE CAS CSCD 2018年第4期721-726,共6页
A laboratory experiment was conducted inside a wind wave tank to investigate the wave induced turbulence. In this experiment, the wave surface elevation and velocity beneath the water surface were measured simultaneou... A laboratory experiment was conducted inside a wind wave tank to investigate the wave induced turbulence. In this experiment, the wave surface elevation and velocity beneath the water surface were measured simultaneously to investigate the relation between the wave status and wave induced turbulence. The profile of the turbulent dissipation rate and Reynolds stress were calculated using experimental data. The effect of the wave status on turbulence is investigated with regard to the wind wave, swell, and mixed wave conditions. It was depicted that the turbulence decreased with increasing depth from the water surface and that the turbulence that was induced by a wave with larger wavelength and wave height is much stronger for the same wave status. Finally, we observed that the wind wave is more effective in activating the wave induced turbulence. 展开更多
关键词 WAVE induced TURBULENCE TURBULENT DISSIPATION RATE wave-turbulence DECOMPOSITION
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Does light-intensity physical activity moderate the relationship between sitting time and adiposity markers in adolescents? 被引量:2
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作者 Ana María Contardo Ayala Jo Salmon +2 位作者 David W.Dunstan Lauren Arundell Anna Timperio 《Journal of Sport and Health Science》 SCIE 2022年第5期613-619,共7页
Background:While the relationship between sedentary time and adiposity markers may be independent of moderate-to-vigorous intensity physical activity(MVPA) among adolescents,little is known about the role of light-int... Background:While the relationship between sedentary time and adiposity markers may be independent of moderate-to-vigorous intensity physical activity(MVPA) among adolescents,little is known about the role of light-intensity physical activity(LIPA) in this relationship.The aim of this cross-sectional study was to examine whether device-measured LIPA and MVPA moderate the associations between objectively measured sitting time and adiposity markers(body mass index(BMI)) and waist circumference(WC)) among adolescents.Methods:This study included accelerometer and inclinometer data obtained from 219 adolescents(age=14.9±1.6 years,mean± SD),collected during 2014 and 2015 in Melbourne,Australia.ActiGraph GT3 X accelerometers were used to determine time spent in total-LIPA(101 counts/min to 3.99 metabolic equivalents(METs)) was dichotomized into low-LIPA(101-799 counts/min) and high LIPA(800 counts/min to 3.99 METs),and MVPA(> 4 METs).The average time spent sitting was obtained from activPAL inclinometers.Anthropometric measures were assessed by trained staff.Interactions between sitting and total-LIPA,low-LIPA,high-LIPA,and MVPA on BMI z-score(zBMI) and WC z-score(zWC),respectively,were examined using linear regression,adjusting for age and sex;and moderation by total-LIPA,low-LIPA,high-LIPA,and MVPA were examined by adding interaction terms.Significant interaction effects were probed by comparing associations at the mean and at 1 SD below and above the mean.Results:Total-LIPA significantly moderated the association between sitting time and zBMI,and low-LIPA significantly moderated the association between sitting time and zBMI and zWC.No other associations were found for total-LIPA,high-LIPA,or MVPA.Specifically,at high levels of total-LIPA(+1 SD),there is a negative association between sitting time and zBMI.In addition,at high levels of low-LIPA(+1 SD),there is a negative association between sitting time and zBMI and zWC.Conclusion:Associations between sitting and adiposity depended on time spent in total-LIPA and low-LIPA,but not high-LIPA or MVPA.Results suggest that increasing time spent in LIP A may provide protection from the deleterious effects of sitting on adiposity markers among adolescents.Experimental evidence is needed to support these conclusions. 展开更多
关键词 Adolescents Anthropometric measures OBESITY Physical activity Sedentary behavior Sitting time
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Physical Bowing Parameters of ZnSxSel-x Ternary Semiconductor from Ab Initio Study 被引量:1
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作者 Badr-eddine Nabil Brahmi Abdelkrim Elhasnaine Merad Samiha Dergal 《材料科学与工程(中英文A版)》 2013年第3期192-199,共8页
关键词 从头计算方法 三元半导体 物理参数 电子能带结构 广义梯度近似 体积弹性模量 晶格参数 三元合金
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THE EFFECT OF HOT DRAWN ON THE PHYSICAL AGING OF ATACTIC POLYSTYRENE
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作者 宋锐 林辛 +2 位作者 陈晶 高金贵 范庆荣 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 1998年第2期176-184,共9页
The physical aging behavior of atactic polystyrene (aPS) films achieved under different drawing conditions has been studied by optical birefringence and modulate differential scanning: calorimeter (m.d.s.c.). The resu... The physical aging behavior of atactic polystyrene (aPS) films achieved under different drawing conditions has been studied by optical birefringence and modulate differential scanning: calorimeter (m.d.s.c.). The results show that on annealing at specific temperature below glass transition temperatue (T-g), the enthalpy relaxation (Delta H) and T-g decrease with increasing of birefringence (Delta n). On the other baud, the effect of molecular draw ratio (MDR) is confusing: Delta H and T-g decrease with increasing of MDR in the early stage of aging, but the MDR's effect become unobvious with the development of aging. It may be concluded that the ordered domain generated by the drawing below or above glass transition temperature will affect the development of physical aging behavior. The viewpoint of cohesional entanglement is used to account for the above observations. 展开更多
关键词 modulated differential scanning calorimetry (m d.s.c.) atactic polystyrene physical aging EXTENSION ORIENTATION
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Diagnosis of Physical and Biological Controls on Phytoplankton Distribution in the Sargasso Sea
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作者 WANG Caixia Paola Malanotte-Rizzoli 《Journal of Ocean University of China》 SCIE CAS 2014年第1期32-44,共13页
The linkage between physical and biological processes is studied by applying a one-dimensional physical-biological coupled model to the Sargasso Sea. The physical model is the Princeton Ocean Model and the biological ... The linkage between physical and biological processes is studied by applying a one-dimensional physical-biological coupled model to the Sargasso Sea. The physical model is the Princeton Ocean Model and the biological model is a five-component system including phytoplankton, zooplankton, nitrate, ammonium, and detritus. The coupling between the physical and biological model is accomplished through vertical mixing which is parameterized by the level 2.5 Mellor and Yamada turbulence closure scheme. The coupled model investigates the annual cycle of ecosystem production and the response to external forcing, such as heat flux, wind stress, and surface salinity, and the relative importance of physical processes in affecting the ecosystem. Sensitivity experiments are also carried out, which provide information on how the model bio-chemical parameters affect the biological system. The computed seasonal cycles compare reasonably well with the observations of the Bermuda Atlantic Time-series Study(BATS). The spring bloom of phytoplankton occurs in March and April, right after the weakening of the winter mixing and before the establishment of the summer stratification. The bloom of zooplankton occurs about two weeks after the bloom of phytoplankton. The sensitivity experiments show that zooplankton is more sensitive to the variations of biochemical parameters than phytoplankton. 展开更多
关键词 physical-biological coupled model ANNUAL CYCLE EXTERNAL FORCING bio-chemical parameter
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Diagnosis of Physical and Biological Control over Phytoplankton in the Gulf of Maine-Georges Bank Region Using an Adjoint Data Assimilation Approach
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作者 WANG Caixia Paola Malanotte-Rizzoli 《Journal of Ocean University of China》 SCIE CAS 2014年第3期356-368,共13页
The linkage between physical and biological processes, particularly the effect of the circulation field on the distribution of phytoplankton, is studied by applying a two-dimensional model and an adjoint data assimila... The linkage between physical and biological processes, particularly the effect of the circulation field on the distribution of phytoplankton, is studied by applying a two-dimensional model and an adjoint data assimilation approach to the Gulf of Maine-Georges Bank region. The model results, comparing well with observation data, reveal seasonal and geographic variations of phytoplankton concentration and verify that the seasonal cycles of phytoplankton are controlled by both biological sources and advection processes which are functions of space and time and counterbalance each other. Although advective flux divergences have greater magnitudes on Georges Bank than in the coastal region of the western Gulf of Maine, advection control over phytoplankton concentration is more significant in the coastal region of the western Gulf of Maine. The model results also suggest that the two separated populations in the coastal regions of the western Gulf of Maine and on Georges Bank are self-sustaining. 展开更多
关键词 physical circulation biological source adjoint data assimilation
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Short bouts of accumulated exercise:Review and consensus statement on definition,efficacy,feasibility,practical applications,and future directions 被引量:1
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作者 Mingyue Yin Yongming Li +43 位作者 Abdul Rashid Aziz Aidan Buffey David J.Bishop Dapeng Bao George P.Nassis Hashim Islam Hongying Wang Jackson J.Fyfe Jianfang Xu Jianxiu Liu Jiexiu Zhao Jingwei Cao Jonathan P.Little Junqiang Qiu Keith M.Diaz Lijuan Wang Liye Zou Max J.Western Meynard L.Toledo Min Hu Minghui Quan Neville Owen Niels B.J.Vollaard Olivier Girard Qingde Shi Richard S.Metcalfe Rodrigo Ramirez-Campillo Ru Wang Waris Wongpipit Weimo Zhu Wenfei Zhu Weigang Xu Xiaochun Wang Xiaoping Chen Xiong Wang Xu Wen Yang Liu Ying Gao Yue Fu Zhaowei Kong Zhenbo Cao Zhengzhen Wang Peijie Chen Lijuan Mao 《Journal of Sport and Health Science》 2026年第2期1-30,共30页
Background:Insufficient physical activity and prolonged sedentary behavior have emerged as major global public health challenges.Short bouts(≤10 min)of accumulated exercise(SBAE)throughout the day may be a promising ... Background:Insufficient physical activity and prolonged sedentary behavior have emerged as major global public health challenges.Short bouts(≤10 min)of accumulated exercise(SBAE)throughout the day may be a promising strategy to mitigate the adverse effects of prolonged sitting and promote physical activity,ultimately promoting overall health.However,previous ambiguity in defining this concept has resulted in a fragmented and inconsistent evidence base,impeding practical applications,the development of guidelines,and policymaking.The purpose of this study is to establish an operational definition of SBAE by synthesizing systematic reviews and research trials alongside an expert consensus.Additionally,it seeks to evaluate acute and long-term efficacy and feasibility,providing evidence-based recommendations for practice and future research directions.Methods:A literature search was performed across PubMed and Web of Science,followed by systematic screening and summarization of eligible studies based on predefined inclusion criteria.Inclusion criteria encompassed various modes/types of SBAE(bouts lasting≤10 min,performed multiple times daily with≥30 min intervals);both aerobic and resistance exercise were considered.Relevant systematic reviews and research trials were included.Methodological quality,risk of bias,and evidence certainty were assessed.Expert consensus was obtained through a survey to evaluate recommendations and agreement levels on findings.Results:After analyzing 27 systematic reviews,135 research studies,and an expert consensus involving 48 researchers from 11 countries,SBAE is defined as any exercise mode of activity,regardless of intensity,that is accumulated in either continuous or intermittent bouts lasting≤10 min per session(including multiple intermittent sets)that are performed multiple times(≥2 sessions/day)per day,with intervals of≥30 min between bouts or otherwise sufficient time for recovery.When used to interrupt prolonged periods of sedentary time,SBAE mitigates the acute adverse effects of sedentary behavior on more than 10 clinical biomarkers of endocrine,cardiovascular,and brain health/function among adults of diverse ages and conditions.Moreover,SBAE was superior for improving acute glycemic control compared to a single continuous exercise session.As a long-term intervention(average of 11 weeks),SBAE can improve over 20 health outcomes,including peak oxygen uptake,resting blood pressure,and metabolic health.Additionally,SBAE might be more effective than continuous exercise for improving longer-term glycemic control and body composition.Long-term completion rates for SBAE interventions are generally high(95%),with low dropout rates(12%)and high adherence rates even without supervision(85%),and its safety has been preliminarily validated.Conclusion:An operational definition of SBAE is provided along with its classification and acute and long-term efficacy.Practical exercise prescription recommendations and evidence-based strategies for various populations and contexts are provided.Future research should focus on generating high-quality evidence for SBAE in 5 key areas:quantification and monitoring,population-specific responses,optimization of exercise prescriptions,intervention efficacy,and practical implementation.Additionally,addressing policy,environmental,and promotional barriers is crucial for transitioning from expert consensus to public consensus,and for facilitating the application of this strategy in real-world environments. 展开更多
关键词 Short bouts of accumulated exercise Exercise snacks Consensus statement Sedentary breaks
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Recent development of flexible perovskite solar cells and its potential applications to aerospace 被引量:1
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作者 Shaoqi Bian Guangshu Xu +4 位作者 Shufang Zhang Qi Jiang Xiaoguang Ma Jingbi You Xinbo Chu 《Journal of Semiconductors》 2025年第5期20-28,共9页
Due to advantages of high power-conversion efficiency(PCE), large power-to-weight ratio(PWR), low cost and solution processibility, flexible perovskite solar cells(f-PSCs) have attracted extensive attention in recent ... Due to advantages of high power-conversion efficiency(PCE), large power-to-weight ratio(PWR), low cost and solution processibility, flexible perovskite solar cells(f-PSCs) have attracted extensive attention in recent years. The PCE of f-PSCs has developed rapidly to over 25%, showing great application prospects in aerospace and wearable electronic devices. This review systematically sorts device structures and compositions of f-PSCs, summarizes various methods to improve its efficiency and stability recent years. In addition, the applications and potentials of f-PSCs in space vehicle and aircraft was discussed. At last, we prospect the key scientific and technological issues that need to be addressed for f-PSCs at current stage. 展开更多
关键词 flexible perovskite solar cells power-conversion efficiency stability aerospace application potential
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Spatial dynamics of phytoplankton assemblages and organic carbon stock in the highly productive Amundsen Sea Polynya and adjacent seasonal ice zone 被引量:1
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作者 Dong Li Jun Zhao +9 位作者 Ji Hu Jianming Pan Jianfeng He Yongming Sun Peisong Yu Xufeng Yang Cai Zhang Haifeng Zhang Weiping Sun Gaojing Fan 《Acta Oceanologica Sinica》 2025年第4期101-120,共20页
Polynyas and their adjacent seasonal ice zones(SIZs)represent the most productive regions in the Southern Ocean,supporting unique food webs that are highly sensitive to climate change.Understanding the dynamics of phy... Polynyas and their adjacent seasonal ice zones(SIZs)represent the most productive regions in the Southern Ocean,supporting unique food webs that are highly sensitive to climate change.Understanding the dynamics of phytoplankton and the carbon pool in these areas is crucial for assessing the role of the Southern Ocean in global carbon cycling.During the late stage of an algal bloom,seawater samples at 14 stations were collected in the Amundsen Sea Polynya(ASP)and adjacent SIZ.Using nutrients,phytoplankton pigments,organic carbon(OC),remote sensing data,and physicochemical measurements,as well as CHEMTAX model simulations,we investigated the response of the phytoplankton crops,taxonomic composition,and OC pool to environmental factors.Our analyses revealed that hydrodynamic regimes of the polynya,adjacent SIZs and open sea were regulated by the regionally varying intrusion of Circumpolar Deep Water,photosynthetically active radiation and sea ice melt water.The ASP exhibited the highest seasonal nutrient utilization rates[ΔN=(1059±386)mmol/m^(2),ΔP=(50±17)mmol/m^(2) andΔSi=(956±904)mmol/m^(2)],while the open sea had lower rates.The integrated chlorophyll a(Chl a)concentration at depths of 0–200 m ranged from 20.4 mg/m^(2) to 1420.0 mg/m^(2) and peaked in the polynya.In the study area,Haptophytes Phaeocystis antarctica was the dominant functional group(34%±27%),and diatoms acted as a secondary contributor(23%±14%).The major functional group and particulate OC(POC)contributor varied from diatoms(36%±12%)in the open sea to haptophytes(48%±31%)in the polynya waters.Strong light conditions and microelement limitations promoted the dominance of P.antarctica(low Fe forms)dominance in the ASP.The strong correlations between the POC and Chl a depth-integrated concentration suggest that the POC was primarily derived from phytoplankton,while dissolved OC(DOC)was influenced by consumer activity and water mass transport.In addition,the transport of OC in the upper 200 m of the water column within the ASP was quantified,revealing the predominantly westward fluxes for both DOC[9.0 mg/(m^(2)·s)]and POC[7.2 mg/(m^(2)·s)].The latitudinal transport exhibited the northward transport of DOC[8.1 mg/(m^(2)·s)]and southward transport of POC[4.3 mg/(m^(2)·s)]movement.These findings have significant implications for enhancing our understanding of how hydrodynamics influence OC cycling in polynya regions. 展开更多
关键词 Amundsen Sea Polynya(ASP) NUTRIENTS hydrodynamic regime phytoplankton crops phytoplankton community structure organic carbon(OC)stock flux
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Effect of Magnetron Sputtered Gas on Microstructure and Hydrogen Adsorption Performance of ZrCoRE Films
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作者 Zhou Chao Ma Zhanji +2 位作者 Li Gang Yang Lamaocao Zhang Huzhong 《稀有金属材料与工程》 北大核心 2025年第6期1451-1456,共6页
ZrCoRE(RE denotes rare earth elements)non-evaporable getter films have significant applications in vacuum packaging of micro-electro mechanical system devices because of their excellent gas adsorption performance,low ... ZrCoRE(RE denotes rare earth elements)non-evaporable getter films have significant applications in vacuum packaging of micro-electro mechanical system devices because of their excellent gas adsorption performance,low activation temperature and environmental friendliness.The films were deposited using DC magnetron sputtering with argon and krypton gases under various deposition pressures.The effects of sputtering gas type and pressure on the morphology and hydrogen adsorption performance of ZrCoRE films were investigated.Results show that the films prepared in Ar exhibit a relatively dense structure with fewer grain boundaries.The increase in Ar pressure results in more grain boundaries and gap structures in the films.In contrast,films deposited in Kr display a higher density of grain boundaries and cluster structures,and the films have an obvious columnar crystal structure,with numerous interfaces and gaps distributed between the columnar structures,providing more paths for gas diffusion.As Kr pressure increases,the film demonstrates more pronounced continuous columnar structure growth,accompanied by deeper and wider grain boundaries.This structural configuration provides a larger specific surface area,which significantly improves the hydrogen adsorption speed and capacity.Consequently,high Ar and Kr pressures are beneficial to improve the adsorption performance. 展开更多
关键词 NEG film magnetron sputtering KRYPTON sputtering pressure hydrogen adsorption performance
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Structural and electronic properties of nitrogen-doped ultrananocrystalline diamond films grown by microwave plasma CVD
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作者 Venkateswara Rao Sodisetti Somnath Bhattacharyya 《新型炭材料(中英文)》 北大核心 2025年第5期1169-1183,I0058-I0064,共22页
Nitrogen doping in chemical vapor deposition-derived ultrananocrystalline diamond(UNCD)films in-creases the electronic conductivity,yet its microstructural effects on electron transport are insufficiently understood.W... Nitrogen doping in chemical vapor deposition-derived ultrananocrystalline diamond(UNCD)films in-creases the electronic conductivity,yet its microstructural effects on electron transport are insufficiently understood.We investigated the formation of nitrogen-induced diaph-ite structures(hybrid diamond-graphite phases)and their role in changing the conductivity.Nitrogen doping in a hy-drogen-rich plasma environment promotes the emergence of unique sp^(3)-sp^(2)bonding interfaces,where diamond grains are covalently integrated with graphitic domains,facilitating a structure-driven electronic transition.High-resolution transmis-sion electron microscopy and selected area electron diffraction reveal five-fold,six-fold and twelve-fold symmetries,along with an atypical{200}crystallographic reflection,confirming diaphite formation in 5%and 10%N-doped UNCD films,while high-er doping levels(15%and 20%)result in extensive graphitization.Raman spectroscopy tracks the evolution of sp^(2)bonding with increasing nitrogen content,while atomic force microscopy and X-ray diffraction indicate a consistent diamond grain size of~8 nm.Cryogenic electronic transport measurements reveal a conductivity increase from 8.72 to 708 S/cm as the nitrogen dop-ing level increases from 5%to 20%,which is attributed to defect-mediated carrier transport and 3D weak localization.The res-ulting conductivity is three orders of magnitude higher than previously reported.These findings establish a direct correlation between diaphite structural polymorphism and tunable electronic properties in nitrogen-doped UNCD films,offering new ways for defect-engineering diamond-based electronic materials. 展开更多
关键词 CVD diamond Nitrogen doping Diamond-graphene composite 3D Weak Localization Diamond electronics
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Quantum-state engineering using enhanced tripartite interactions in atom–photon–phonon hybrid systems 被引量:1
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作者 Yaowu Guo Jiaqiang Zhao +2 位作者 Lianzhen Cao Yingde Li Hong-Yan Lu 《Chinese Physics B》 2025年第2期282-288,共7页
We introduce a hybrid cavity optomechanical model capable of generating significant genuine tripartite interactions and entanglement among coherent degrees of freedom.However,realizing and controlling such tripartite ... We introduce a hybrid cavity optomechanical model capable of generating significant genuine tripartite interactions and entanglement among coherent degrees of freedom.However,realizing and controlling such tripartite interactions and their entanglement pose crucial challenges that remain largely unexplored.In this work,we predict a tripartite coupling mechanism within a hybrid quantum system consisting of a vibrating mechanical oscillator,a two-level atom and a singlefrequency cavity field.We specifically propose a mechanism for tripartite and cross-Kerr nonlinear coupling through displacement and squeezing transformations.By adjusting the optical amplitude of the pump light,we can effectively enhance these nonlinear couplings,facilitating the manipulation of entangled and squeezed states.The resulting tripartite genuine entanglement exhibits distinct evolutionary characteristics.Notably,when the pump light amplitude is large,the tripartite entanglement persists for longer time.Additionally,the phonon displays characteristics of both cooling and squeezing.Our study presents a pathway for exploring and exploiting controllable multipartite entanglement,as well as achieving phonon cooling and squeezing with the assistance of a mesoscopic harmonic oscillator.This work underscores the innovative potential of our model in advancing the field of optomechanics and quantum entanglement. 展开更多
关键词 cross-Kerr nonlinear coupling tripartite coupling tripartite entanglement
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Meridional Shift of Southern Ocean Mesoscale Eddies Since the 1990s 被引量:1
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作者 Fei SHI Qian SHI +5 位作者 Yiyong LUO Renhao WU Qinghua YANG Jiping LIU Jason YANG Jun SONG 《Advances in Atmospheric Sciences》 2025年第12期2529-2538,I0025-I0028,共14页
Mesoscale eddies play a central role in the poleward oceanic heat flux in the Southern Ocean.Previous studies have documented changes in the location of temperature fronts in the Southern Ocean,but little attention ha... Mesoscale eddies play a central role in the poleward oceanic heat flux in the Southern Ocean.Previous studies have documented changes in the location of temperature fronts in the Southern Ocean,but little attention has been paid to changes in the genesis locations of mesoscale eddies.Here,we provide evidence from three decades of satellite altimetry observations for the heterogeneity of the poleward shift of mesoscale activities,with the largest trend of~0.23°±0.05°(10 yr)^(-1) over the Atlantic sector and a moderate trend of~0.1°±0.03°(10 yr)^(-1) over the Indian sector,but no significant trend in the Pacific sector.The poleward shift of mesoscale eddies is associated with a southward shift of the local westerly winds while being constrained by the major topographies.As the poleward shift of westerly winds is projected to persist,the poleward oceanic heat flux from mesoscale eddies may influence future ice melt. 展开更多
关键词 mesoscale eddies Southern Ocean poleward trend
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