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51.
Continuous jumping behavior, a kind of endurance locomotion, plays important roles in insect ecological adaption and survival. However, the methods used for the efficient evaluation of insect jumping behavior remain largely lacking. Here, we developed a locomotion detection system named JumpDetector with automatic trajectory tracking and data analysis to evaluate the jumping of insects. This automated system exhibits more accurate, efficient, and adjustable performance than manual methods. By using this automatic system, we characterized a gradually declining pattern of continuous jumping behavior in 4th‐instar nymphs of the migratory locust. We found that locusts in their gregarious phase outperformed locusts in their solitary phase in the endurance jumping locomotion. Therefore, the JumpDetector could be widely used in jumping behavior and endurance locomotion measurement.  相似文献   
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The morphology and the effect of an endurance training programme on tonic muscle fibres were studied in chub Leuciscus cephalus , by means of histochemistry and immunohistochemistry, electronmicroscopy and morphometry/stereology. Location and distribution, SDH- and mATPase-activity, reaction to an anti-tonic myosin antibody and ultrastructural features of the fibre type were investigated. With regard to training conditions, fibre size was not significantly affected. However, an increase in the volume densities of mitochondria, lipid and myofibrils can be observed, suggesting a training influence on the aerobic capacity of the so-called tonic muscle fibres. Based on the quantitative findings, the fine structure and the response to training, similarities with intermediate muscle fibres and the functional role of these so-called tonic muscle fibres are discussed.  相似文献   
54.
摘要 目的:观察八段锦联合心脏运动康复对急性心肌梗死(AMI)急诊经皮冠状动脉介入术(PCI)后患者心功能、运动耐力和生活质量的影响。方法:选择2019年6月~2021年6月期间我院收治的AMI急诊PCI术后患者100例,根据随机数字表法分为对照组(心脏运动康复干预,50例)和观察组(八段锦联合心脏运动康复干预,50例),观察两组患者心功能、运动耐力及生活质量改善情况,对比两组心脏不良事件发生率。结果:干预后,两组左心室射血分数(LVEF)较干预前升高,且观察组高于对照组(P<0.05)。干预后,两组左室舒张末期内径(LVDD)、左室收缩末期内径(LVDS)、B型脑利钠肽(BNP)较干预前下降,且观察组低于对照组(P<0.05)。干预后,两组运动持续时间(ED)、峰值摄氧量(VO2peak)及无氧阈值(AT)较干预前升高,且观察组高于对照组(P<0.05)。干预后,两组健康调查简表(SF-36)各维度评分较干预前升高,且观察组高于对照组(P<0.05)。观察组的心脏不良事件发生率低于对照组(P<0.05)。结论:八段锦联合心脏运动康复用于AMI急诊PCI患者的术后干预中,可促进心功能恢复,改善患者的运动耐力及生活质量,同时还可降低心脏不良事件发生率。  相似文献   
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为探讨运动训练和停训对鲈鲤Percocypris pingi幼鱼运动能力的影响,将480尾(体质量为2.18g±0.12g,体长为5.33cm±0.09cm)鲈鲤幼鱼随机分为4组(每组120尾):对照组(C)、无氧训练组(An)、4BL·s^-1组(BL为体长)(H)和2BL·s^-1组(L)(H组和L组每天均训练8h),在15℃±2℃条件下持续训练30d后停训。分别在训练前(T0)、训练30d后(T30)、停训20d后(DT20)和停训50d后(DT50)测定鲈鲤幼鱼的临界游泳速度(Ucrit)和1.5Ucrit条件下的耐受时间。结果显示:(1)持续运动训练显著提高了鲈鲤幼鱼的有氧和无氧运动能力,而力竭运动训练只提高了鲈鲤幼鱼的无氧运动能力;(2)停训20d后,L组的Ucrit显著高于An组和C组,An组、H组和C组间的差异无统计学意义,而An组和H组的耐受时间仍显著高于对照组,L组和C组间的差异无统计学意义;(3)停训50d后,实验组和C组间Ucrit和耐受时间的差异均无统计学意义。因此,运动训练显著提高了鲈鲤幼鱼的有氧和无氧运动能力,但不同训练方式的提升效果及其维持时间不同。  相似文献   
56.
  • 1 The flight apparatus in butterflies, as well as in other insects, is costly to manufacture. Since most animals live in a world where resources are limited, trade‐offs are expected and available resources must thus be allocated between flight and other functions, such as reproduction.
  • 2 To mitigate this trade‐off, previous studies have shown that butterflies can break down flight muscles in the thorax as they age in order to use muscle nutrients for reproduction.
  • 3 Although breakdown of flight muscles is expected to reduce flight ability, relative flight muscle mass (thorax mass/body mass) in many butterfly species does not decrease with age. The aim of the present study was to test the relationship between flight endurance and adult age in the green‐veined white butterfly Pieris napi (L.). The tests were performed in the laboratory at five different temperatures.
  • 4 The results showed that age has a significant influence on butterfly flight endurance; older butterflies showed reduced flight endurance. Male butterflies fly for a longer time than females and flight endurance increases with temperature in both sexes.
  相似文献   
57.
Differences in predation intensity experienced by organisms can lead to divergent natural selection, driving evolutionary change. Western mosquitofish (Gambusia affinis) exhibit larger caudal regions and higher burst-swimming capabilities when coexisting with higher densities of predatory fish. It is hypothesized that a trade-off between steady (constant-speed cruising; important for acquiring resources) and unsteady (rapid bursts and turns; important for escaping predators) locomotion, combined with divergent selection on locomotor performance (favouring steady swimming in high-competition scenarios of low-predation environments, but unsteady swimming in high-predation localities) has caused such phenotypic divergence. Here, I found that morphological differences had a strong genetic basis, and low-predation fish required less hydromechanical power during steady swimming, leading to increased endurance. I further found individual-level support for cause-and-effect relationships between morphology, swimming kinematics and endurance. Results indicate that mosquitofish populations inhabiting low-predation environments have evolved increased steady-swimming abilities via stiffer bodies, larger anterior body/head regions, smaller caudal regions and greater three-dimensional streamlining.  相似文献   
58.
食虫沟瘤蛛的饥饿耐受性   总被引:2,自引:0,他引:2  
肖永红  贺一原  杨海明 《生态学报》2006,26(6):1725-1731
对我国多数稻区共享的优势种蜘蛛食虫沟瘤蛛进行饥饿耐受性测定,结果显示食虫沟瘤蛛的耐饥时间以及组内个体耐饥力的变异幅度与温度高低呈负相关。在35、25℃和15℃3种试验温度下,食虫沟瘤蛛的耐饥时间及变异幅度均与龄期呈正相关;在5℃时,耐饥时间极大延长,组内变异系幅度亦急剧增大,但此时耐饥时间和变异幅度均与龄期呈负相关。在高温35℃和低温5℃下,3个龄期组的耐饥时间差异不显著(p>0.05);但在适宜温度25℃和15℃时,3个龄期组之间的耐饥时间差异显著(p<0.05)。同一龄期组的食虫沟瘤蛛在任意两种不同的温度条件下,其耐饥时间的差异性均达到极显著水平(p<0.01)。4种试验温度条件下,处于饥饿状态的食虫沟瘤蛛各龄期组的阶段死亡率均具有正态分布特点,可用正态分布模型M=1σ2π.e-(T2-σ2μ)2进行拟合;并可根据正态分布的特点得出食虫沟瘤蛛的饥饿半致死时间(T50)和致死时间(T95)。  相似文献   
59.
摘要 目的:探讨弹力带抗阻训练、中等强度有氧运动联合应用对稳定性冠心病患者心肺功能、血管内皮功能、运动耐力的影响。方法:选择2020年9月~2022年4月期间我院收治的稳定性冠心病患者70例,按照随机数字表法分为对照组(35例,中等强度有氧运动)和联合组(35例,对照组的基础上接受弹力带抗阻训练)。对比两组运动耐力、血管内皮功能指标[超声颈动脉内膜-中层厚度(IMT) 、内皮依赖性血管舒张功能(FMD)值、Crouse斑块积分]、心肺功能指标[左心室射血分数(LVEF)、心脏每搏输出量(SV)、最大摄氧量(VO2max)和氧脉搏(O2pulse)]、生活质量和心血管不良事件发生率。结果:干预后,两组6分钟步行试验(6MWT)升高,且联合组高于对照组(P<0.05)。干预后,两组LVEF、SV、VO2max、O2pulse升高,且联合组高于对照组(P<0.05)。干预后,两组生理/社会功能、躯体疼痛、生理/情感职能、精力、总体/精神健康各维度评分升高,且联合组高于对照组(P<0.05)。干预后,两组IMT缩小,FMD升高,Crouse斑块积分下降,且联合组的变化程度大于对照组(P<0.05)。两组心血管不良事件发生率对比无差异(P>0.05)。结论:稳定性冠心病患者采用弹力带抗阻训练和中等强度有氧运动联合干预可改善心肺功能和血管内皮功能,提高运动耐力及生活质量,具有较好的临床应用价值。  相似文献   
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