The seismic risk analysis results of 79 cities in Xinjiang are presented, and the bedrock peak ground accelerations under three seismic levels and their ratios are discussed. Then, the relationship between earthquake ...The seismic risk analysis results of 79 cities in Xinjiang are presented, and the bedrock peak ground accelerations under three seismic levels and their ratios are discussed. Then, the relationship between earthquake environments and the seismic risk analysis results of different exceeding probabilities are researched. The results show that minor and major earthquake motion parameters calculated from moderate earthquakes do not have a consistent probability and the ratio of bedrock peak accelerations under different exceedance probabilities are dosdy correlated with earthquake environments.展开更多
Coral snakes and their mimics often have brightly colored banded patterns, generally associated with warning colora- tion or mimicry. However, such color patterns have also been hypothesized to aid snakes in escaping ...Coral snakes and their mimics often have brightly colored banded patterns, generally associated with warning colora- tion or mimicry. However, such color patterns have also been hypothesized to aid snakes in escaping predators through a "flicker-fusion" effect. According to this hypothesis, banded color patterns confuse potential predators when a snake transitions from resting to moving because its bands blur together to form a different color. To produce this motion blur, a moving snake's bands must transition faster than the critical flicker-fusion rate at which a predator's photoreceptors can refresh. It is unknown if coral snakes or their mimics meet this requirement. We tested this hypothesis by measuring the movement speed and color pat- terns of two coral snake mimics, Lampropeltis triangulum campbelli and L. elapsoides, and comparing the frequency of color transitions to the photoreceptor activity of the avian eye. We found that snakes often produced a motion blur, but moving snakes created a blurring effect more often in darker conditions, such as sunrise, sunset, and nighttime when these snakes are often active. Thus, at least two species of coral snake mimics are capable of achieving flicker-fusion, indicating that their color patterns may confer an additional defense aside from mimicry展开更多
基金Supported by the tenth "Five-Year Plan" pivotal project "Research on Seismic Safety Evaluation and Structure Seismic Resistance"and"Project for Visiting Scholars of CSB"
文摘The seismic risk analysis results of 79 cities in Xinjiang are presented, and the bedrock peak ground accelerations under three seismic levels and their ratios are discussed. Then, the relationship between earthquake environments and the seismic risk analysis results of different exceeding probabilities are researched. The results show that minor and major earthquake motion parameters calculated from moderate earthquakes do not have a consistent probability and the ratio of bedrock peak accelerations under different exceedance probabilities are dosdy correlated with earthquake environments.
文摘Coral snakes and their mimics often have brightly colored banded patterns, generally associated with warning colora- tion or mimicry. However, such color patterns have also been hypothesized to aid snakes in escaping predators through a "flicker-fusion" effect. According to this hypothesis, banded color patterns confuse potential predators when a snake transitions from resting to moving because its bands blur together to form a different color. To produce this motion blur, a moving snake's bands must transition faster than the critical flicker-fusion rate at which a predator's photoreceptors can refresh. It is unknown if coral snakes or their mimics meet this requirement. We tested this hypothesis by measuring the movement speed and color pat- terns of two coral snake mimics, Lampropeltis triangulum campbelli and L. elapsoides, and comparing the frequency of color transitions to the photoreceptor activity of the avian eye. We found that snakes often produced a motion blur, but moving snakes created a blurring effect more often in darker conditions, such as sunrise, sunset, and nighttime when these snakes are often active. Thus, at least two species of coral snake mimics are capable of achieving flicker-fusion, indicating that their color patterns may confer an additional defense aside from mimicry