The Beijing Swift(Apus apus pekinensis)is a typical cavity-nesting bird that often nests inside holes and crevices in old architectures.Direct observation of their breeding behaviour is challenging and their breeding ...The Beijing Swift(Apus apus pekinensis)is a typical cavity-nesting bird that often nests inside holes and crevices in old architectures.Direct observation of their breeding behaviour is challenging and their breeding ecology is thus poorly studied.In this study,we analysed light-level geolocation data collected from six Beijing Swifts for the first time.Our results showed that geolocators can make comprehensive inference of their incubation period and behaviour.As a cost-effective and non-invasive method,geolocators can not only facilitate discovering migration routes,but also can be widely applied in the study of avian reproductive behaviour,especially in cavity-nesting bird species.We further discussed the characteristics and merits of this method and compared with other conventional nest-monitoring methods in recording birds.展开更多
A novel frame shift and integral technique for the enhancement of low light level moving image sequence is introduced. According to the technique, motion parameters of target are measured by algorithm based on differe...A novel frame shift and integral technique for the enhancement of low light level moving image sequence is introduced. According to the technique, motion parameters of target are measured by algorithm based on difference processing. To obtain spatial relativity, images are shifted according to the motion parameters. As a result, the processing of integral and average can be applied to images that have been shifted. The technique of frame shift and integral that includes the algorithm of motion parameter determination is discussed, experiments with low light level moving image sequences are also described. The experiment results show the effectiveness and the robustness of the parameter determination algorithm, and the improvement in the signal-to-noise ratio （SNR） of low light level moving images.展开更多
Tracking and mating data of Common Terns(Sterna hirundo)breeding in a single colony in north-eastern Germany were used to test for assortative mating in regards to migratory phenotypes.These birds use the eastern and ...Tracking and mating data of Common Terns(Sterna hirundo)breeding in a single colony in north-eastern Germany were used to test for assortative mating in regards to migratory phenotypes.These birds use the eastern and western African migration routes and three different wintering areas along the African coast.However,no assortative mating was found for either migratory route or wintering area,as birds using both flyways and all three wintering areas paired randomly,which might be explained by a lack of difference in the arrival date at the colony between the groups.These results might indicate a low degree of genetic fixation of migratory route and wintering area in the Common Tern,which might hint that migratory direction and wintering sites could be passed to young terns via social learning,either by joining the parents or migratory flocks of conspecifics.If migratory phenotypes are passed on by a parent,it seems more likely that it is passed from father to young,as female Common Terns tend to leave the colony earlier and males provide the majority of post-fledging care.展开更多
电子轰击型有源像素传感器(Electron Bombarded Active Pixel Sensor,EBAPS)作为一种数字化微光成像器件,以其成像系统具有小型化、低成本和低功耗的优势,以及在昼夜条件下连续拍摄时具备清晰成像的能力,成为微光成像领域的研究热点。...电子轰击型有源像素传感器(Electron Bombarded Active Pixel Sensor,EBAPS)作为一种数字化微光成像器件,以其成像系统具有小型化、低成本和低功耗的优势,以及在昼夜条件下连续拍摄时具备清晰成像的能力,成为微光成像领域的研究热点。文章基于国产某型EBAPS微光器件,利用FPGA作为核心处理器,完成了EBAPS器件驱动电路、图像处理和跟踪电路、显示电路的设计。同时,构建了满足昼夜复用的光学系统,搭建了一种小型化的手持成像跟踪系统。实验结果表明,该EBAPS昼夜成像系统可在1×10^(-4)~1×10^(4) lx照度条件下实现良好的成像和跟踪效果。展开更多
近视患病率逐年攀升,已成为全球性的重大公共卫生问题之一。目前的近视防控措施,如角膜塑形镜、离焦框架眼镜、软性离焦角膜接触镜、低浓度阿托品滴眼液均存在不足之处。重复低强度红光(RLRL)近年来成为儿童近视控制的手段之一。多项临...近视患病率逐年攀升,已成为全球性的重大公共卫生问题之一。目前的近视防控措施,如角膜塑形镜、离焦框架眼镜、软性离焦角膜接触镜、低浓度阿托品滴眼液均存在不足之处。重复低强度红光(RLRL)近年来成为儿童近视控制的手段之一。多项临床研究结果均表明,RLRL照射能够抑制儿童青少年近视的快速增长。近期一篇研究报告"Cone Density Changes After Repeated Low-Level Red Light Treatment in Children With Myopia"(《重复低强度红光治疗后近视儿童的视锥细胞密度变化》),在近视儿童的家长中引起了广泛讨论。本文详细分析此文章研究方法及结果,探讨是否能得出RLRL会影响近视儿童黄斑视锥细胞密度的结论。展开更多
基金funded by SHAN SHUI Conservation Centre,Beijing。
文摘The Beijing Swift(Apus apus pekinensis)is a typical cavity-nesting bird that often nests inside holes and crevices in old architectures.Direct observation of their breeding behaviour is challenging and their breeding ecology is thus poorly studied.In this study,we analysed light-level geolocation data collected from six Beijing Swifts for the first time.Our results showed that geolocators can make comprehensive inference of their incubation period and behaviour.As a cost-effective and non-invasive method,geolocators can not only facilitate discovering migration routes,but also can be widely applied in the study of avian reproductive behaviour,especially in cavity-nesting bird species.We further discussed the characteristics and merits of this method and compared with other conventional nest-monitoring methods in recording birds.
文摘A novel frame shift and integral technique for the enhancement of low light level moving image sequence is introduced. According to the technique, motion parameters of target are measured by algorithm based on difference processing. To obtain spatial relativity, images are shifted according to the motion parameters. As a result, the processing of integral and average can be applied to images that have been shifted. The technique of frame shift and integral that includes the algorithm of motion parameter determination is discussed, experiments with low light level moving image sequences are also described. The experiment results show the effectiveness and the robustness of the parameter determination algorithm, and the improvement in the signal-to-noise ratio （SNR） of low light level moving images.
基金the Landesamt für Umwelt,Naturschutz und Geologie Mecklenburg-Vorpommern(LUNG M-V)the Orthop?die+Vital Zentrum Piro GmbH+2 种基金the Institut für Vogelforschung“Vogelwarte Helgoland”(IfV)the German Ornithologists’Society(DO-G,project“Migration behaviour of Western Pomeranian terns”)the University of Greifswald(“AG Vogelwarte”)。
文摘Tracking and mating data of Common Terns(Sterna hirundo)breeding in a single colony in north-eastern Germany were used to test for assortative mating in regards to migratory phenotypes.These birds use the eastern and western African migration routes and three different wintering areas along the African coast.However,no assortative mating was found for either migratory route or wintering area,as birds using both flyways and all three wintering areas paired randomly,which might be explained by a lack of difference in the arrival date at the colony between the groups.These results might indicate a low degree of genetic fixation of migratory route and wintering area in the Common Tern,which might hint that migratory direction and wintering sites could be passed to young terns via social learning,either by joining the parents or migratory flocks of conspecifics.If migratory phenotypes are passed on by a parent,it seems more likely that it is passed from father to young,as female Common Terns tend to leave the colony earlier and males provide the majority of post-fledging care.
文摘近视患病率逐年攀升,已成为全球性的重大公共卫生问题之一。目前的近视防控措施,如角膜塑形镜、离焦框架眼镜、软性离焦角膜接触镜、低浓度阿托品滴眼液均存在不足之处。重复低强度红光(RLRL)近年来成为儿童近视控制的手段之一。多项临床研究结果均表明,RLRL照射能够抑制儿童青少年近视的快速增长。近期一篇研究报告"Cone Density Changes After Repeated Low-Level Red Light Treatment in Children With Myopia"(《重复低强度红光治疗后近视儿童的视锥细胞密度变化》),在近视儿童的家长中引起了广泛讨论。本文详细分析此文章研究方法及结果,探讨是否能得出RLRL会影响近视儿童黄斑视锥细胞密度的结论。
