Structural system design and earthquake response analysis of prefabricated pile-plate bridge

With the advancement of building technology, the pile-plate structure, which originated in railway engineering, has been adopted into highway engineering. This study presents a new pile-plate structure connecting node. The addition of energy-dissipating components at the nodes and the use of non-shrinkage concrete at the joints demonstrate its novelty. The node’s ability to enter the plastic stage is enhanced, resulting in increased seismic performance. In this study, the seismic performance and energy consumption capacity of the pile plate joint were studied by numerical model, and the results showed that the stagnation curve of the pipe pile under low cycle reciprocating load was full and had good energy consumption capacity. Under the action of random seismic vibration, the displacement of the pile plate structure in one direction is up to 0.023 m, which meets the requirements of the specification. The innovative pile-plate joints are used in a nonlinear dynamic time-history analysis of the constructed bridge structure

Sex differences in alarm response and predation risk in the fresh water snail Pomacea canaliculata

Many animals show alarm responses (ARs) to chemical cues released from predators or injured conspecifics. However, the prey often makes a trade-off between predation avoidance and reproduction, resulting in pronounced sex differences in AR and in sex-biased predation. This phenomenon has rarely been investigated in snails. The freshwater snail Pomacea canaliculata is reported to exhibit an AR to chemical cues released from predators or injured conspecifics. Here, we investigate the sex differences in AR in the snail to chemical cues released from its predator turtle Chinemys reevesii and injured conspecifics. By exposing adult females and males of equivalent size to turtles, we also evaluate the sex-biased predation in the snail. We find that females respond to chemical cues significantly more strongly than males. The predation experiment shows that more females survived than males after a week of predation. These results suggest that males may reduce their antipredator behaviour in order to increase the chance of mating, suggesting a trade-off between predation avoidance and reproduction