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Lionel Feugre Gabriella Gibson Nicholas C. Manoukis Olivier Roux 《Journal of the Royal Society Interface》2021,18(177)
Given the unsurpassed sound sensitivity of mosquitoes among arthropods and the sound source power required for long-range hearing, we investigated the distance over which female mosquitoes detect species-specific cues in the sound of station-keeping mating swarms. A common misunderstanding, that mosquitoes cannot hear at long range because their hearing organs are ‘particle-velocity’ receptors, has clouded the fact that particle velocity is an intrinsic component of sound whatever the distance to the sound source. We exposed free-flying Anopheles coluzzii females to pre-recorded sounds of male An. coluzzii and An. gambiae s.s. swarms over a range of natural sound levels. Sound levels tested were related to equivalent distances between the female and the swarm for a given number of males, enabling us to infer distances over which females might hear large male swarms. We show that females do not respond to swarm sound up to 48 dB sound pressure level (SPL) and that louder SPLs are not ecologically relevant for a swarm. Considering that swarms are the only mosquito sound source that would be loud enough to be heard at long range, we conclude that inter-mosquito acoustic communication is restricted to close-range pair interactions. We also showed that the sensitivity to sound in free-flying males is much enhanced compared to that of tethered ones. 相似文献
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It is crucial to uncover the mystery of water cluster and structural motif to have an insight into the abundant anomalies bound to water. In this context, the analysis of influence factors is an alternative way to shed light on the nature of water clusters. Water structure has been tentatively explained within different frameworks of structural models. Based on comprehensive analysis and summary of the studies on the response of water to four externalities (i.e., temperature, pressure, solutes and external fields), the changing trends of water structure and a deduced intrinsic structural motif are put forward in this work. The variations in physicochemical and biological effects of water induced by each externality are also discussed to emphasize the role of water in our daily life. On this basis, the underlying problems that need to be further studied are formulated by pointing out the limitations attached to current study techniques and to outline prominent studies that have come up recently. 相似文献
4.
《Journal of the European Ceramic Society》2017,37(15):4687-4692
Cu-Se compounds have attracted more attentions as a low-cost, low toxicity thermoelectric materials. In this work, p-type Cu2Sex compound powders were prepared by solution syntheses, including the wet chemistry method and hydrothermal synthesis method. The reaction mechanisms were investigated, showing that the NaOH contents affected the phase structure of the final product. Polycrystalline Cu2Sex bulk materials were obtained by densifying the powders using spark plasma sintering (SPS) and obtained the maximum ZT value of 0.75 at 623 K, which is currently the highest reported value for the Cu-Se system at this temperature. We also found that the introduced oxides could suppress the long-range migration of Cu ions in Cu-Se system to avoid the decomposition of the materials. 相似文献
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We address the complex relationship between the stability, variability, and adaptability of psychological systems by decomposing the global variance of serial performance into two independent parts: the local variance (LV) and the serial correlation structure. For two time series with equal LV, the presence of persistent long-range correlations (or 1/?β noise) increases the global variance. We hypothesized that a coadjustment between these two determinants of variability constitutes a resource for adaptive systems whose appropriate functioning under critical conditions requires the outcome variance to be limited. To test this hypothesis, we looked at the bimanual coordination dynamics at comfortable (stable) and critical (close to phase transition) frequencies. Results showed that a negative correlation appeared gradually as the theoretical stability of coordination modes decreased and reached significance only in the critical condition. We propose that the emergence of a mutual adjustment between LV and serial correlations might be an indicator of effective adaptation to stabilize behavior. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
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为了适应现代战争的需要,提高远程打击系统的精确打击能力至关重要.将粒子滤波与EM算法等其他算法相结合,从给定的数据中,提取状态信息的最优估计值,对于提高远程打击系统的精确性、快速性和实时性有非常重要的现实意义和理论意义.首先给出了粒子滤波算法的原理和仿真应用,然后分析了粒子滤波在目标状态信息的估计、信号检测、目标识别跟... 相似文献
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The purpose of this study is to build a post-construction 3D computer model of the historical settlement of Beipu Township in Taiwan as an application and reference framework. The cultural assets were digitally preserved in a post-construction and modified form as an attempt to fulfill the life-cycle management of data for culture workers, researchers and architects. The scan process was managed in four hierarchies: the whole region, the seven historical buildings, the four streets and the special features, in different scales. The final digital model integrates research results from all involved parties, integrates local practice needs, represents hypothesis in city development, enhances historical understanding and interpretation, and facilitates remote access. 相似文献
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The centrality and energy dependence of rapidity correlation patterns are studied in Au+Au collisions by using AMPT with string melting, RQMD and UrQMD models. The behaviors of the shortrange correlation (SRC) and the long-range correlation (LRC) are pres 相似文献
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为探究川中丘陵区干湿动态动力学机制,提供旱涝预测的理论依据。根据川中丘陵区8个气象站点1958~2013年逐日气象资料,采用Penman—Monteith 模型计算潜在蒸散量,构建出湿润指数。在此基础上,基于去趋势波动分析方法(DFA),对逐月、分季节、极端干湿湿润指数进行长程相关性分析,并探讨了影响湿润指数长程相关性的气象因子。结果表明:除南充、遂宁外,其余地区逐月湿润指数变化长程相关,并非完全随机;分季节与极端干湿湿润指数均具有长程相关性;对于不同季节而言,长程相关性以夏季最强,秋、冬两季次之,春季最弱,对于极端气候而言,极端湿润长程相关性强于极端干旱;通过对湿润指数与气象因子长程相关性一致性分析,降水标度指数与湿润指数标度指数呈显著正相关。 相似文献
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通过对城镇小区二次给水泵站特点、分类及目前市场应用的分析.提出了适用于城市供水调度监控系统中二次增压供水远程监控设计方案.进而建立完善的二次给水泵站远程智能网络监视管理。 相似文献