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Training session intensity affects plasma redox status in amateur rhythmic gymnasts 被引量:1
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作者 Marianna Bellafiore Antonino Bianco +6 位作者 Giuseppe Battaglia Maria Silvia Naccari Giovanni Caramazza Johnny Padulo Karim Chamari Antonio Paoli Antonio Palma 《Journal of Sport and Health Science》 SCIE 2019年第6期561-566,共6页
Purpose:The aim of this study was to examine systemic responses of oxidant/antioxidant status following 2 training sessions of different intensity in amateur rhythmic gymnasts.Methods:Before the experimental training,... Purpose:The aim of this study was to examine systemic responses of oxidant/antioxidant status following 2 training sessions of different intensity in amateur rhythmic gymnasts.Methods:Before the experimental training,10 female gymnasts performed a gradually increased exercise test to assess maximal heart rate,maximal oxygen consumption,and anaerobic threshold.They executed 2 intermittent training sessions separated by 48 h of recovery(48 h-post R):the first was performed at low-moderate intensity(LMI)and the second at high intensity(HI).Blood samples were collected immediately preand post-training and 48 h-post R.Hydroperoxide level(OxL)and total antioxidant capacity(TAC)were photometrically measured.Results:OxL was significantly higher in post-training and 48 h-post R following HI than the same conditions after an LMI session(HI vs.LMI post-training:381.10±46.17(mean±SD)vs.344.18±27.94 Units Carratelli(U.CARR);48 h-post R:412.21±26.61 vs.373.80±36.08 U.CARR).There was no change in TAC between the 2 training sessions investigated.In LMI training,OxL significantly decreased in post-training and increased to reach the baseline at 48 h-post R,whereas TAC increased only at 48 h-post R.In HI training,OxL significantly increased to reach a high oxidative stress 48 h-post R,whereas TAC was lower in post-training than pre-training.Conclusion:The pattern of OxL and TAC levels implies different regulation mechanisms by HI and LMI training sessions.High oxidative stress induced by an HI protocol might be associated with both insufficient TAC and recovery time at 48 h necessary to restore redox balance. 展开更多
关键词 Antioxidant capacity Exercise PHYSIOLOGY Free RADICALS Oxidative stress Reactive oxygen species rhythmic GYMNASTICS Training INTENSITY
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Effects of adaptation to handling on the circadian rhythmicity of blood solutes in Mongolian gerbils 被引量:1
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作者 Xingchen Liu Xiang Zheng +2 位作者 Yihan Liu Xiaoyan Du Zhenwen Chen 《Animal Models and Experimental Medicine》 CSCD 2019年第2期127-131,共5页
The Mongolian gerbil has been widely used in many research fields and has been reported to be a diurnal laboratory animal. The circadian rhythmicity of these gerbils was investigated in the present study by measuring ... The Mongolian gerbil has been widely used in many research fields and has been reported to be a diurnal laboratory animal. The circadian rhythmicity of these gerbils was investigated in the present study by measuring two hormones that show daily oscillations, cortisol and ACTH, in serum using ELISA kits. The levels of the two hormones were highest at 8:00 am and their rhythmic changes were similar to those in humans. In addition, the influence of stress of handling and blood collection on the physiological parameters of the gerbils was examined. After adaptation to handling for 1 week, some serum parameters in the animals changed. Handling and blood collection did not impact significantly on the following parameters: creatine kinase (CK), lactate dehydrogenase (LD), alanine aminotransferase (ALT), aspartate transaminase (AST), blood urea nitrogen (BUN), and albumin (ALB). However, blood glucose (GLU), total protein (TP) and globulin (GLB) significantly increased while creatinine (CRE) and albumin/globulin (A/G) significantly decreased after adaptation. This work further confirms that the Mongolian gerbil is a diurnal animal and also indicates that a suitable adaptation procedure is necessary for getting reliable results when performing experiments using these animals. 展开更多
关键词 CIRCADIAN rhythmicITY diurnal animals HANDLING ADAPTATION Mongolian GERBILS physiological parameters stress
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Rhythmic and Spоradic Changes in the Rate of Beta Decays: Possible Reasons 被引量:1
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作者 Alexander G. Parkhomov 《Journal of Modern Physics》 2018年第8期1617-1632,共16页
In a number of experiments, when detecting particles emitted in beta decays, periodic oscillations of count rate with an amplitude up to tenths of a percent and short bursts vastly exceeding the usual count rate are f... In a number of experiments, when detecting particles emitted in beta decays, periodic oscillations of count rate with an amplitude up to tenths of a percent and short bursts vastly exceeding the usual count rate are found. At the same time, several experiments did not detect any differences from the “normal” course of beta decays greater than 0.01%. The article shows that the inconsistency of the experimental results is due to different measurement technique. The assumption is made of the possible participation in the beta decay processes of cosmic slow neutrinos, which makes it possible to explain in a comprehensive manner not only periodic and sporadic changes in the beta decay rate, but also a number of other incomprehensible phenomena associated with beta radioactivity. On the basis of the experiments carried out, an estimate is made of the flux density of slow cosmic neutrinos. 展开更多
关键词 Beta RADIOACTIVITY Nuclear DECAY RATE Solar NEUTRINOS Relic NEUTRINOS Variations of RADIOACTIVITY rhythmic OSCILLATIONS
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Comparing Coordination Abilities of 10-11 Years Old Girls Practicing Basketball and Rhythmic Gymnastic
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作者 Georgi Venelinov Brestnichki 《Journal of Sports Science》 2015年第3期134-137,共4页
关键词 comparing COORDINATION 10-11 years old GIRLS BASKETBALL rhythmic GYMNASTICS
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Some Tonal and Rhythmical Sequences in the Vocal Language of Dogs as Significant Earthquake Precursors
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作者 Giovanna de Liso 《Open Journal of Earthquake Research》 2018年第4期221-268,共48页
A monitoring of multiple physical parameters in a moderate seismic area in Western Piedmont (NW Italy) and the simultaneous observation of the behaviour of numerous species of domestic and wild animals gave in a perio... A monitoring of multiple physical parameters in a moderate seismic area in Western Piedmont (NW Italy) and the simultaneous observation of the behaviour of numerous species of domestic and wild animals gave in a period of over twenty years the possibility to distinguish the unusual animal behaviours due to local earthquake nucleation from other causes. In particular, the observation of the body and vocal language of dogs (Canis familiaris) in the same area has permitted not only to specify the different meanings of vocal language in connection to their body language, but also to classify the minimum elements into a vocal language that is linked together by tonal and rhythmical sequences of sounds that form a semantic lexicon. The usage of the same tonal and rhythmical vocal sequences in similar or identical situations, which are experienced by different groups of dogs, induces us to verify whether it could be possible to link particular vocal sequences to precise physical anomalies before earthquakes. The individuation of physical anomalies due to an earthquake nucleation or due to a hydro-geological destabilization, is possible thanks to a continuous long-term monitoring of some parameters. Moreover, the complexity of the vocal language of dogs increases if the dogs live in an area with a law population density. Then the correlation between some vocal sequences and some seismic precursors is better if dogs live free in yard or on farms, if they are in good health, and if they can establish a strong social relation of group. When dogs live closed in yards of houses that are far apart, they communicate with each other with an amazing vocal language, full of questions and answers, imitations of sequences, and information about situations that may be harmful to them. 展开更多
关键词 VOCAL Language DOGS rhythmicAL And Tonal SEQUENCES Syntax Formant VOCAL Tract Semantics Seismic Precursors Earthquakes Magnetic DECLINATION Sudden COMMENCEMENT Infra-Sounds Brontides
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Vibration Analysis and Fatigue Assessment of Floors.Part I:Human Rhythmic Activities
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作者 Ana C.S.da Silva Elisângela A.R.Santos +2 位作者 Leandro A.Deus Mayara M.Martins JoséG.S.da Silva 《Journal of Civil Engineering and Architecture》 2021年第10期497-503,共7页
Structural problems associated with excessive vibration of building floor systems when subjected to human rhythmic activities have been frequent.In this context,this research work aims to develop an analysis methodolo... Structural problems associated with excessive vibration of building floor systems when subjected to human rhythmic activities have been frequent.In this context,this research work aims to develop an analysis methodology to evaluate the human comfort and assess the fatigue performance of steel-concrete composite floors when subjected to human rhythmic activities(aerobics).The investigated structural model corresponds to a steel-concrete floor with dimensions of 10 m×10 m and a total area of 100 m^(2).The numerical model developed for the dynamic analysis of the floor adopted the usual mesh refinement techniques present in finite element method(FEM)simulations implemented in the ANSYS program.The investigated floor dynamic response was calculated through the consideration of people practicing rhythmic activities on the structure,in order to verify the occurrence of excessive vibration and to assess the human comfort.The fatigue assessment is based on a linear cumulative damage rule through the use of the Rainflow-counting algorithm and S-N curves from traditional design codes.The results indicated that,in several analysed situations,the investigated floor presents excessive vibration and user’s discomfort.On the other hand,the structure service life values were higher than those proposed by the design codes,ensuring that the members,connections and joints will not fail by fatigue cracking. 展开更多
关键词 Steel-concrete composite floors human rhythmic activities vibration analysis human comfort fatigue assessment.
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The Rhythmic Beauty of The Solitary Reaper
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作者 涂颖 张志刚 《海外英语》 2019年第19期204-205,共2页
Wordsworth who focuses on common people’s common life as his major theme gives readers a sense of universality of human destiny via the description of sounds in The Solitary Reaper through poetic style,rhythmic modes... Wordsworth who focuses on common people’s common life as his major theme gives readers a sense of universality of human destiny via the description of sounds in The Solitary Reaper through poetic style,rhythmic modes and rhetorical devices which shows musical beauty of the poem. 展开更多
关键词 rhythmic BEAUTY POETIC STYLE rhythmic MODES RHETORICAL DEVICES
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Proteomic Identification of Rhythmic Proteins in Maize Seedling Leaves 被引量:2
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作者 FENG Wan-jun GUO Bao-jian +3 位作者 YAO Ying-yin PENG Hui-ru SUN Qi-xin NI Zhong-fu 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2012年第12期1958-1967,共10页
Plant leaves respond to day/night cycling in a number of physiological ways. At the mRNA level, the expression of some genes changes during the 24 h period. To determine which proteins exhibited a rhythmic pattern of ... Plant leaves respond to day/night cycling in a number of physiological ways. At the mRNA level, the expression of some genes changes during the 24 h period. To determine which proteins exhibited a rhythmic pattern of expression, proteomic profiles in maize seedling leaves were analyzed by high-throughput two-dimensional gel electrophoresis, combined with MALDI-TOF MS technology. Of the 464 proteins that were detected with silver staining in a pH range of 4-7, 17 (3.66%) showed clock rhythmicity in their abundance. These proteins belonged to diverse functional groups and proteins involved in photosynthesis and carbon metabolism were over-represented. These findings provide a new perspective on the relationship between the physiological functions of leaves and the clock rhythmic system. 展开更多
关键词 蛋白质组学 幼苗叶片 玉米 MALDI-TOF 鉴定 艺术 MRNA水平 二维凝胶电泳
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Central pattern generation underlying Limulus rhythmic behavior patterns 被引量:1
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作者 Gordon A.Wyse 《Current Zoology》 SCIE CAS CSCD 北大核心 2010年第5期537-549,共13页
Many behavioral activities of the horseshoe crab Limulus are rhythmic, and most of these are produced in large partby central pattern generators within the CNS. The chain of opisthosomal ('abdominal') ganglia ... Many behavioral activities of the horseshoe crab Limulus are rhythmic, and most of these are produced in large partby central pattern generators within the CNS. The chain of opisthosomal ('abdominal') ganglia controls gill movements of ventilationand gill cleaning, and the prosomal ring of fused ganglia (brain and segmental 'thoracic' ganglia) controls generation offeeding and locomotor movements of the legs. Both the opisthosomal CNS and the prosomal CNS can generate behaviorally appropriatepatterns of motor output in isolation, without movements or sensory input. Preparations of the isolated opisthosomalCNS generate rhythmic output patterns of motor activity characterized as fictive ventilatory and gill cleaning rhythms. Moreover,CNS preparations also express longer-term patterns, such as intermittent ventilation or sequential bouts of ventilation and gillcleaning. Such longer-term patterns are commonly observed in intact animals. The isolated prosomal CNS does not spontaneouslygenerate the activity patterns characteristic of walking, swimming, and feeding. However, perfusion of octopamine in the isolatedprosomal CNS activates central pattern generators underlying rhythmic chewing movements, and injection of octopamine into intactLimulus promotes the chewing pattern of feeding, whether or not food is presented. Our understanding of the ability of neuromodulatorssuch as octopamine to elicit or alter central motor programs may help to clarify the central neural circuits of patterngeneration that produce and coordinate these rhythmic 展开更多
关键词 行为模式 模式生成 节奏 中央 中枢神经系统 中枢模式发生器 运动控制
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Recent Activity of the Badu-Longwei Segment,Guguan-Xiangong Fault in Southern Liupanshan,Constrained by Rhythmic Sediment Lithology and Geomorphic Characteristics 被引量:1
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作者 SHI Zhigang YUAN Daoyang +2 位作者 HE Wengui LIU Xingwang WANG Jun 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2015年第4期1165-1175,共11页
This study's objective was to investigate the Guguan-Xiangong Fault, which lies in the southern Liupanshan area, through satellite image interpretation and field observations. Guguan-Xiangong Fault is divided into... This study's objective was to investigate the Guguan-Xiangong Fault, which lies in the southern Liupanshan area, through satellite image interpretation and field observations. Guguan-Xiangong Fault is divided into five subsegments; among these, the Badu-Longwei segment has been the most recently active. The geomorphic features of the Badu-Longwei segment are clearly displayed, including multiple high fault scarps with fresh bedrock free faces. There is significant evidence for Holocene activity of the three fault sections, located in Renhuashu, Tianjiagou, and Xinjiecun respectively. The three sections feature distinct episodic deposition and fault scratches. Based on 14 Cdating and field observations on the three fault sections, two or more paleoearthquakes across the Badu-Longwei fault segment are ascertained, between 5874±116 and 5430±140 a BP, and after 2037±83 a BP respectively. The Badu-Longwei segment of the Guguan-Xiangong Fault is preliminarily extrapolated as the seismogenic structure of the 600 A.D. Qin-Long earthquake. 展开更多
关键词 六盘山地区 地貌特征 沉积物 故障 岩性 韵律 卫星图像解译 断层崖
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“约定”与“再约定”——对“rhythmic gymnastics”汉译的再思考
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作者 林飞 张顺生 《中国科技术语》 2020年第1期51-56,共6页
中国媒体通常将体育赛事项目中的“体操”与“artistic gymnastics”等同起来,而将“艺术体操”与“rhythmic gymnastics”等同起来。然而,从语言逻辑上来说,这种翻译存在问题。为了避免引起误会,无论从语言自身逻辑自洽角度而言,还是... 中国媒体通常将体育赛事项目中的“体操”与“artistic gymnastics”等同起来,而将“艺术体操”与“rhythmic gymnastics”等同起来。然而,从语言逻辑上来说,这种翻译存在问题。为了避免引起误会,无论从语言自身逻辑自洽角度而言,还是为了实现同国际接轨,都应当将“rhythmic gymnastics”“再约定”译作“韵律体操”,而将“artistic gymnastics”“再约定”译作“艺术体操”,实现语言回归。翻译语言的“约定俗成”不是一劳永逸的。为了实现语言逻辑自洽,翻译语言“约定”之后局部需要“再约定”。翻译核心概念时,应重视语言逻辑问题,既要重视语内连贯,也要重视语际连贯。 展开更多
关键词 艺术体操 韵律体操 翻译 “约定” “再约定”
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Cortical Arousal Strategies in Left-Handers during the Aural Perception and Manual Playback of Mono-and Polyphonic Rhythmical Patterns
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作者 Pavlovych Olga Sergiyivna Morenko Alevtyna Grigorivna Kotyk Olena Adamivna Vlasjuk Svitlana Sergiyivna 《Journal of Life Sciences》 2012年第12期1408-1413,共6页
关键词 听觉感知 左撇子 播放 手动 韵律模式 和弦 皮层 大脑皮质
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Exploring human rhythmic gait movement in the role of cerebral cortex signal
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作者 董玮 王如彬 张志康 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2011年第2期223-230,共8页
The rhythmic movement is a spontaneous behavior due to the central pattern generator(CPG).At present,the CPG model only shows the spontaneous behavior,butdoes not refer to the instruction regulation role of the cerebr... The rhythmic movement is a spontaneous behavior due to the central pattern generator(CPG).At present,the CPG model only shows the spontaneous behavior,butdoes not refer to the instruction regulation role of the cerebral cortex.In this paper,a modified model based on the Matsuoka neural oscillator theory is presented to better show the regulation role of the cerebral cortex signal to the CPG neuronal network.The complex interaction between the in put signal and other parameters in the CPG networkis established,making all parameters of the CPG vary with the input signal.In this way,the effect of the input signal to the CPG network is enhanced so that the CPG network can express the self-regulation movement state instead of being limited to the spontaneous behavior,and thus the regulation role of the cerebral cortex signal can be reffected.Numerical simulation shows that the modified model can generate various movement forms with different modes,frequencies,and interchanges between them.It is revealed in theories that the cerebral cortex signal can regulate the mode and frequency of the gait in the course of the gait movement. 展开更多
关键词 中央模式生成器(CPG ) 步法运动有韵律的运动服的外皮信号变换功能
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The Evaluation Rules in the View of the Rhythmic Gymnastics Judges
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作者 Catarina Leandro Lurdes Avila-Carvalho +1 位作者 Elena Sierra-Palmeiro Marta Bobo-Arce 《Journal of Sports Science》 2016年第4期232-240,共9页
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A Perspective on Rhythmic Gymnastics Performance Analysis Powered by Intelligent Fabric 被引量:1
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作者 Dan Zhu Zhenyu Zhang +12 位作者 Min Chen Pan Li Yuanzhuo Xiang Jingyu Ouyang Zhiheng Huang Xiaojuan Liu Fuhong Wang Maiping Yang Hongtao Zeng Ping Hong Lei Wei Chong Hou Guangming Tao 《Advanced Fiber Materials》 SCIE EI 2023年第1期1-11,共11页
Performance analysis is an important tool for gymnasts and coaches to assess the techniques,strengths,and weaknesses of rhythmic gymnasts during training.To have an accurate insight about the motion and postures can h... Performance analysis is an important tool for gymnasts and coaches to assess the techniques,strengths,and weaknesses of rhythmic gymnasts during training.To have an accurate insight about the motion and postures can help the optimization of their performance and offer personalized suggestions.However,there are three primary limitations of traditional perfor-mance analysis systems applied in rhythmic gymnastics:(1)Inability to quantify anthropometric data in an imperceptible way,(2)labor-intensive nature of data labeling and analysis,and(3)lack of monitoring of all-round and multi-dimensional perspectives of the target.Thus,an advanced performance analysis system for rhythmic gymnastics is proposed in this paper,powered by intelligent fabric.The system uses intelligent fabric to detect the physiological and anthropometric data of the gymnasts.After a variety of data are collected,the analysis component is implemented by artificial intelligence techniques resulting in behavior recognition,decision-making,and other functions assisting performance improvement.A feasible solution to implementing the analysis component is the use of the hyperdimensional computing technique.In addition,four typical applications are presented to improve training performance.Powered by intelligent fabric,the proposed advanced performance analysis system exhibits the potential to promote innovative technologies for improving training and competi-tive performance,prolonging athletic careers,as well as reducing sports injuries. 展开更多
关键词 rhythmic gymnastics Intelligent fabric Augmented reality Artificial intelligence
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以文为诗,以诗为词,以古为律:清代诗话的破体观念论析
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作者 任竞泽 李增 《厦门大学学报(哲学社会科学版)》 北大核心 2024年第1期158-172,共15页
清代诗话是清代文体史料及文体批评的渊薮,其中破体观念在清诗话文体理论中又最为突出和独具特色。目前学界整理的煌煌16册174种清诗话中论及以文为诗、以诗为词、以古为律及其对立范畴以诗为文、以词为诗、以律为古等破体批评的诗话就... 清代诗话是清代文体史料及文体批评的渊薮,其中破体观念在清诗话文体理论中又最为突出和独具特色。目前学界整理的煌煌16册174种清诗话中论及以文为诗、以诗为词、以古为律及其对立范畴以诗为文、以词为诗、以律为古等破体批评的诗话就多达63部,贯穿整个清代诗话史和诗学史。清代诗学史上具有重要学术地位的学者诸如王夫之、叶燮、王士祯、沈德潜、赵翼、翁方纲、潘德舆等,在对相关破体范畴进行文体批评时,往往褒贬倾向不一,或肯定,或否定,或辩证看待,引发了旷日持久的学术争鸣,并在演进递嬗中形成了系统的破体观念体系,堪称中国古代破体理论的集大成和总结者。这对于纵向观照和比较研究宋元明诗话破体观念具有重要的文体批评史学术价值和理论意义。 展开更多
关键词 清代诗话 以文为诗 以诗为词 以古为律 破体观念
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中外优秀男子400 m栏运动员分段成绩及全程节奏比较
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作者 郑哲 王辉 +1 位作者 朱厚伟 孙刚 《浙江师范大学学报(自然科学版)》 CAS 2024年第2期219-226,共8页
为揭示优秀男子400 m栏运动员分段成绩及全程节奏特征,探究中外优秀男子400 m栏运动员成绩和技术的发展特征及具体差距,搜集了男子400 m栏世界排名前3的运动员沃霍姆、本杰明、桑托斯及中国运动员谢智宇近3年的主要比赛决赛视频,采用Dar... 为揭示优秀男子400 m栏运动员分段成绩及全程节奏特征,探究中外优秀男子400 m栏运动员成绩和技术的发展特征及具体差距,搜集了男子400 m栏世界排名前3的运动员沃霍姆、本杰明、桑托斯及中国运动员谢智宇近3年的主要比赛决赛视频,采用Dartfish软件对视频进行逐帧解析,并对比赛成绩、步幅、步频、速度及节奏变化进行了分析与比较.结果显示:国外优秀运动员在H1—H2阶段速度达到全程最大,为(8.77±0.72) m/s,且前3栏速度变化呈现“N”形态,谢智宇在绝对速度上低于国外优秀运动员,在H1—H2阶段差距最大,差值接近1.00 m/s;国外优秀运动员栏间步数基本固定,大部分运动员在比赛中会有1次步数调整,第1次调整在H7居多,谢智宇在栏间的步数变化次数多于国外优秀运动员. 展开更多
关键词 男子400 m栏 步频步幅 分段成绩 节奏策略 比较
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条带状铁建造消失之谜:铁-硅互层机制研究进展与展望
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作者 王瑞敏 沈冰 《地学前缘》 EI CAS CSCD 北大核心 2024年第1期111-126,共16页
条带状铁建造(banded iron formation, BIF)是指以铁-硅韵律层结构为特征的化学沉积岩。BIF不仅是重要的铁资源,也是记录早期地球演化、早期微生物活动和大气-海洋氧化还原状态的重要载体。BIF的出现和消失与重要环境事件的演变密切相关... 条带状铁建造(banded iron formation, BIF)是指以铁-硅韵律层结构为特征的化学沉积岩。BIF不仅是重要的铁资源,也是记录早期地球演化、早期微生物活动和大气-海洋氧化还原状态的重要载体。BIF的出现和消失与重要环境事件的演变密切相关。BIF在>3.8 Ga首次出现,并在第一次大氧化事件前大量形成,在1.8~0.8 Ga沉积中断,而在成冰纪雪球地球冰期中复现,最终消失在显生宙的氧化海洋中。传统模型认为BIF的出现与消失主要受控于海洋中Fe(Ⅱ)离子的含量。在1.8~0.8 Ga期间,构造-岩浆-热液活动减弱,海洋氧化还原剧变(氧化/硫化)导致海水中的Fe(Ⅱ)被大量耗尽,BIF消失。然而,地球化学证据表明中元古代深海区域仍处于铁化状态,即Fe(Ⅱ)可以稳定存在的氧化还原状态;沉积学证据也表明中元古代仍有大量的铁岩沉积。这些富铁沉积的大量出现,表明中元古代的海洋仍具有沉积铁岩/富铁层的条件,只是不再出现BIF这种“铁-硅互层”的韵律沉积。因此,BIF在1.8~0.8 Ga的沉积中断并不是由Fe(Ⅱ)耗尽造成的,而很可能与海水中铁-硅循环变化导致“铁-硅互层”沉积模式的改变有关。本文对BIF的地质学特征进行了概述,深入探讨了BIF中富铁-富硅层的沉积模式,并从Fe(Ⅱ)的来源差异和Fe(Ⅱ)的氧化差异及Fe(Ⅲ)的保存差异3方面全面综述了BIF “铁-硅互层”机制的研究进展。在此基础上,尝试找出解决中元古代BIF消失之谜的可能方向。最后,对BIF的成因机制所承载的前寒武纪铁-硅生物地球化学循环、早期地球演化过程和早期生命信息等方面提出展望。 展开更多
关键词 条带状铁建造 铁循环 硅循环 韵律层沉积 前寒武纪
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基于中枢模式发生器的机器人足端轨迹规划
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作者 张峰 曹乐 +1 位作者 徐浩洋 张思河 《中国医学物理学杂志》 CSCD 2024年第1期72-80,共9页
提出一种仿生足端轨迹控制法,与传统方法相比,该方法用单个CPG神经元,将振荡器产生的轨迹直接作用于六足机器人足端,通过逆向求解各关节角度,节律摆动机器人各足实现横向行走。可调节CPG振荡器中的负载因子,周期,幅值等参数,实现六足机... 提出一种仿生足端轨迹控制法,与传统方法相比,该方法用单个CPG神经元,将振荡器产生的轨迹直接作用于六足机器人足端,通过逆向求解各关节角度,节律摆动机器人各足实现横向行走。可调节CPG振荡器中的负载因子,周期,幅值等参数,实现六足机器人足端轨迹中的步距,步幅以及在摆动相过程中的前摆轨迹和后摆轨迹调节。通过Matlab与Coppeliasim联合仿真,验证了改进后的模型应用在足端轨迹的可行性,与传统方法相比,参数调节灵活性高,并发处理效果好。 展开更多
关键词 六足机器人 中枢模式发生器 Hopf振荡器 足端轨迹 节律运动
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论六朝至初唐诗体赋的文律特征及文体意义
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作者 王亚萍 《重庆第二师范学院学报》 2024年第1期51-57,128,共8页
五七言诗体赋是六朝初唐文坛常见的文学现象,以诗体赋为代表的骈赋与其他骈文、辞赋相比呈现出新的文律特征。以六朝初唐五七言诗体赋为研究对象,分析诗体赋的基本特征,对其中五七言诗的句式和声律状况进行全面考察,并与近体诗律要求相... 五七言诗体赋是六朝初唐文坛常见的文学现象,以诗体赋为代表的骈赋与其他骈文、辞赋相比呈现出新的文律特征。以六朝初唐五七言诗体赋为研究对象,分析诗体赋的基本特征,对其中五七言诗的句式和声律状况进行全面考察,并与近体诗律要求相对照,对比诗句和骈文对句的句法差异,考察文人从诗赋两种文体对近体诗声律的探索,从中寻绎出六朝初唐诗赋、骈文融合的文体意义。安史之乱前后及中唐时期随着儒学变迁与古文运动的兴起,明道文章观成为主流,诗体赋呈现律赋与古赋的分化与转型,诗体赋逐渐走向衰落。 展开更多
关键词 诗体赋 文律特征 文体意义
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