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121.
Gabriele Gerlach Andrea Hodgins-Davis Bradley MacDonald Rebecca C. Hannah 《Behavioral ecology and sociobiology》2007,61(11):1765-1770
Zebrafish (Danio rerio) larvae prefer the olfactory cues of kin to non-kin. We examined the potential benefits of kin preference by comparing growth
rate, shoaling, and aggressive behavior in juvenile zebrafish housed in groups of either familiar kin or unfamiliar non-kin.
Over an observation period of 5 days, the animals grew 33% more in kin groups; however, neither shoaling nor the frequency
of aggressive interactions was different in groups of related versus unrelated individuals. Shoaling behavior increased with
increasing observation time and increasing age, while aggressive behavior remained the same. We conclude that associating
with kin probably creates a less stressful environment that allows for higher growth rates, which can lead to higher direct
fitness based on increased survival and earlier reproduction. Kin recognition leading to kin-structured groups may therefore
be under positive selection. 相似文献
122.
Pérez Pastor RM García Alonso S Quejido Cabezas AJ 《Environmental monitoring and assessment》2002,75(1):35-55
Multivariate techniques have been applied to the set of dataobtained after one year sampling of volatile organic compounds(VOCs), including volatile aldehydes in the area of Madrid inorder to evaluate the possible correspondence among groups ofanalysed compounds, as far as modelling of different emissionsources in relation to location and season. The measurements were carried out at four sites in Madrid, characteristic for urban and suburban areas. Additionally, as reference, a rural area 100 km far from the city was considered. Results of correlation analysis, factor and cluster analysis are presented.Higher correlations were found between variables related withtraffic emissions. Factor analysis results showed two mainsignificant variables related to anthropogenic and biogenicemissions respectively. In relation to cluster analysis, samples were grouped according to sampling site and seasonal variations. 相似文献
123.
Informational constraints can be an important limitation on the accuracy of recognition. One potential constraint is the use
of recognition information from the same sources in multiple discriminatory contexts. Worker wood ants, Formica fusca, discriminate eggs based on their maternal sources of origin in two main contexts: recognition of eggs laid by nestmate versus
non-nestmate queens and recognition of worker-laid versus queen-laid eggs. We manipulated the experience of F. fusca workers in laboratory colonies to both worker-laid and queen-laid eggs by transferring eggs between colonies in order to
investigate whether these two contexts of egg discrimination are independent. Experience of non-nestmate queen-laid eggs significantly
increased worker acceptance of both familiar (18% accepted) and unfamiliar (10%) queen-laid eggs compared to control workers
without experience of eggs other than those laid by their own colony’s queen (2%). In contrast, worker acceptance of worker-laid
eggs was not affected by variation in the egg experience of workers (14% in workers from control colonies exposed only to
eggs from their own colony’s queen versus 19% and 17% in workers from colonies which had received eggs laid by either a non-nestmate
queen or nestmate workers, respectively). Our results suggest that these two recognition contexts do not strongly constrain
each other and are different in their ontogeny. In particular, worker-laid eggs are universally discriminated against by workers
from colonies with a queen whatever the egg experience of the workers, while non-nestmate queen-laid eggs are strongly discriminated
against only by workers without experience of eggs laid by more than one queen. 相似文献
124.
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126.
Robert Bogucki Marek Cygan Christin Brangwynne Khan Maciej Klimek Jan Kanty Milczek Marcin Mucha 《Conservation biology》2019,33(3):676-684
Photo identification is an important tool for estimating abundance and monitoring population trends over time. However, manually matching photographs to known individuals is time-consuming. Motivated by recent developments in image recognition, we hosted a data science challenge on the crowdsourcing platform Kaggle to automate the identification of endangered North Atlantic right whales (Eubalaena glacialis). The winning solution automatically identified individual whales with 87% accuracy with a series of convolutional neural networks to identify the region of interest on an image, rotate, crop, and create standardized photographs of uniform size and orientation and then identify the correct individual whale from these passport-like photographs. Recent advances in deep learning coupled with this fully automated workflow have yielded impressive results and have the potential to revolutionize traditional methods for the collection of data on the abundance and distribution of wild populations. Presenting these results to a broad audience should further bridge the gap between the data science and conservation science communities. 相似文献
127.
提出利用模糊模式识别技术对瓦斯涌出异常进行动态预警的新思路;通过对已知巷道的瓦斯含量监测数据和素描图进行分析,提取引起瓦斯涌出异常的前兆特征作为模式识别的特征向量,来对实时监测的巷道的工况进行判断,确定其是否存在瓦斯涌出异常的可能性。该方法将传统煤矿安全监控系统事后报警转变成事前预警,提高了系统的可用性。 相似文献
128.
为有效预防职业性肌肉骨骼疾患(WMSDs),提出基于计算机视觉技术与快速全身评估(REBA)结合的作业姿势评估方法,以手工搬运作业为例,通过人体姿态识别AlphaPose模型检测作业姿势,利用提取的各关节点空间位置信息计算身体各部位关节角度;利用SG滤波法处理身体遮挡、光线等对数据的影响,有效保留数据变化信息的同时消除数据突变;根据身体关节角度范围与危害程度对应关系自动评判作业姿势的风险大小。研究结果表明:作业姿势评估方法可通过采集的视频数据自动评估搬运作业的姿势危险性,降低WMSDs风险,通过分析不同下蹲取物姿势风险,可论证作业姿势评估方法的可行性,为及时改善搬运作业中的不安全动作提供参考。 相似文献
129.
Chemically mediated communication is common in spiders but has been poorly studied in burrowing tarantulas. This study aimed
to determine whether chemical cues influence the behaviour of females of Brachypelma vagans, a Mexican species of tarantula, during encounters with previously inhabited burrows or with extracts from the silk of conspecific
females. In laboratory choice tests, female tarantulas entered a burrow that had previously been inhabited by a conspecific
female significantly more frequently than a burrow that had never been inhabited. The identity of the previous inhabitant
also affected the number of spiders that chose to enter a burrow. Spiders were quicker to choose and enter a burrow previously
inhabited by themselves than a burrow previously inhabited by a conspecific or a burrow that had not been previously inhabited.
Hexane, methanol and dichloromethane extracts of conspecific silk elicited different responses from female tarantulas when
extracts were placed on filter paper disks at one end of an experimental arena with a control filter paper disk, on to which
the corresponding solvent alone had been pipetted, placed on the other end of the arena. Spiders showed the strongest responses
to hexane extracts of silk, with a significant preference to move towards the hexane extract and a significantly greater period
of time spent in proximity to the hexane extract compared to the control disk. Overall and in contrast to expectations, tarantulas
were most strongly attracted to the cues left by other conspecific females. As encounters between B. vagans females usually lead to aggression and mortality of one of the participants, we conclude that chemical cues are not signals
that are deliberately released by burrow-inhabiting females but may inadvertently escape and cannot be easily suppressed. 相似文献
130.
The floc morphology was investigated in a continuous-flow reactor, in order to understand the evolution of flocs in practical flocculation and sedimentation processes in water utilities. Kaolin-humic acid suspension was used as the test water, and polyaluminum chloride was chosen as the coagulant. An in-situ recognition system was applied to analyze the floc size, boundary fractal dimension, and eccentricity ratios. Particle numbers and turbidity were also determined in the sedimentation stage. At a coagulant dose of 1 mg/L as Al, the average floc size increased from 62 to 78 μm and the boundary fractal dimension was around 1.14, suggesting that flocs were compact and continuously grew during the entire flocculation process. However, with the dose increased to 5 mg/L, the average floc size decreased and stabilized at around 65 μm, with the fractal dimension of 1.20. It can be concluded that the excess coagulant doses resulted in the formation of chain-shaped, lower density, and more branched structure flocs, thereby restricting flocs' further growth in the subsequent flocculation. Floc morphology analysis suggested that charge neutralization dominated in the initial flocculation stage, then the bridge and sweep mechanisms were dominant in the subsequent flocculation. In addition, compared with the traditional inclined plate settler, a novel V-shaped plate settler introduced in this study had an advantage in small size floc(less than 5 μm) removal. The V-shaped region could promote aggregate restructuring and re-flocculation; therefore, the V-shaped plate settler provides an alternative method for sedimentation. 相似文献