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Feasibility study on the submerged floating tunnel in Qiongzhou Strait, China

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Jiang B. , Liang B. , Wu S.

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EN

Abstract: Currently, one of the challenging tasks for Chinese engineering community is to construct a water-way crossing of Qiongzhou Strait in the south of China. This project has also gained significant attention from researchers in academia. The study presented herein is centered on providing a feasible solution for ac-complishing the above mentioned task. Initially, different alternatives as the best location, judged on the basis of the environmental constraints, are studied. Then the comparison between various structural solutions such as suspension bridge, submarine tunnel and SFT is presented. Among these solutions, SFT appears to be a very suitable alternative for Qiongzhou Strait waterway crossing due to distinctive advantages, like shorter distance, lower cost, less impact on environment and navigation, etc. Based on the appropriate conception for cross sections, support systems, materials, joints and connection schemes, a numerical model is developed by means of the FEM software ANSYS/Fluent. It is then analyzed under the influence of different environmental loading conditions, varying the wave heights and lengths, current velocities and water depths, which are typical in Qiongzhou Strait. The numerical results reveal that the proposed SFT solution performs safely even under extreme weather conditions

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Development of vocalizations in the flat-headed bats, Tylonycteris pachypus and T. robustula (Chiroptera: Vespertilionidae)

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Zhang L. , Jones G. , Parsons S. , Liang B. , Zhang S.

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tom 07

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nr 1

EN

The development of vocalizations during postnatal growth in the flat-headed bats, Tylonycteris pachypus and T. robustula in South China is described. Females of both species gave birth to twins at the end of May, and the infants flew in the last ten days of June. Vocalizations served as precursors to echolocation calls and as isolation calls (i-calls) used to attract mothers. As the infants grew, the frequency of i-calls and precursor calls increased. The duration of i-calls increased little before 6-day old and then decreased. At the same time, the duration of echolocation precursor calls decreased. The directive calls that the mother or the infant emitted when searching for each other are also described. Female directive calls are lower in frequency and longer in duration than their echolocation calls, and the duration of infant directive calls is longer than those of the i-calls and precursor calls.

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Fruit-feeding behaviour and use of olfactory cues by the fruit bat Rousettus leschenaulti: an experimental study

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Tang Z. H. , Sheng L. X. , Parsons S. , Cao M. , Liang B. , Zhang S. Y.

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nr 3

EN

This paper describes the feeding behaviour ofRousettus leschenaulti Desmarest, 1820 on lychees, the preferred cultivated food of this bat in captive conditions. We found that feeding comprised 25–30% of the total activity of these animals in a flight cage and that feeding durations were not significantly different between two sexes. To evaluate the role of odor and vision in foraging behaviour, we provided animals with artificial lychees, real lychees and artificial lychees soaked in the juice of real lychees and we recorded the number of feeding approaches to the different “fruit” types. The results indicated that bats approached real fruit significantly more than artificial fruit, and that the number of approaches to the soaked artificial fruit was also significantly higher than to the unsoaked artificial fruit. There were no significant differences between sexes in approach rates to any “fruit” type. We discuss the role of different sensory cues in the foraging behaviour of these bats and emphasize that the olfactory cue is important in detecting food resources and discriminating between different kinds of food items.

4

Lycium barbarum polysaccharide protects HSF cells against ultraviolet-induced damage through the activation of Nrf2

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Liang B. , Peng L. , Li R. , Li H. , Mo Z. , Dai X. , Jiang N. , Liu Q. , Li Z. , Zhu H.

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tom 23

EN

Background: Lycium barbarum polysaccharide (LBP) is considered an antioxidant agent. NF-E2-related factor-2 (Nrf2) is an important regulator for protection against UV damage. In this study, we verified the performance of LBP and the correlation between LBP and Nrf2. Methods: HSF cells were treated with LBP to determine dose and time dependencies. An antioxidant response element (ARE) reporter was designed to monitor the activity of the Nrf2 antioxidant pathway. Results: For HSF cells, the optimal LBP treatment was 300 μg/ml for 3 h. The AREreporter assay showed that LBP could increase the robustness of p-Nrf2. Treatments with genistein and LY294002 reduced of nuclear p-Nrf2 after 24 h. LBP increased the level of nuclear Nrf2, which functions by both phosphorylation and nuclear translocation. Silencing Nrf2 led to increased reactive oxygen species (ROS) levels, lower cell viability, and decreased superoxide dismutase (SOD) and glutathione peroxidase (GSP-PX) levels. This induced a higher level of lipid peroxide (LPO). However, LBP could decrease the levels of ROS and LPO and enhance the levels of SOD and GSP-PX. Conclusion: LBP protects HSF cells against UV damage via the regulation of Nrf2.