The ability to identify emotional arousal in heterospecific vocalizations may facilitate behaviors that increase survival opportunities. Crucially, this ability may orient inter-species interactions, par- ticularly be...The ability to identify emotional arousal in heterospecific vocalizations may facilitate behaviors that increase survival opportunities. Crucially, this ability may orient inter-species interactions, par- ticularly between humans and other species. Research shows that humans identify emotional arousal in vocalizations across multiple species, such as cats, dogs, and piglets. However, no previ- ous study has addressed humans" ability to identify emotional arousal in silver foxes. Here, we adopted low- and high-arousal calls emitted by three strains of silver fox--Tame, Aggressive, and Unselected--in response to human approach. Tame and Aggressive foxes are genetically selected for friendly and attacking behaviors toward humans, respectively. Unselected foxes show aggres- sive and fearful behaviors toward humans. These three strains show similar levels of emotional arousal, but different levels of emotional valence in relation to humans. This emotional information is reflected in the acoustic features of the calls. Our data suggest that humans can identify high- arousal calls of Aggressive and Unselected foxes, but not of Tame foxes. Further analyses revealed that, although within each strain different acoustic parameters affect human accuracy in identifying high-arousal calls, spectral center of gravity, harmonic-to-noise ratio, and F0 best predict humans' ability to discriminate high-arousal calls across all strains. Furthermore, we identified in spectral center of gravity and F0 the best predictors for humans' absolute ratings of arousal in each call. Implications for research on the adaptive value of inter-specific eavesdropping are discussed.展开更多
To investigate the roles of HtrA protein in bacterial adaption to stresses, htra gene was cloned from an Escherichia coli strain isolated from silver fox, double digested, and ligated into the prokaryotic expression v...To investigate the roles of HtrA protein in bacterial adaption to stresses, htra gene was cloned from an Escherichia coli strain isolated from silver fox, double digested, and ligated into the prokaryotic expression vector pET32a. Then, the recombinant plasmid pET32a-htra was transformed into E. coli BL21 competent cells. The over-expression of His-HtrA protein was induced by the addition of IPTG at a final concentration of 1 mmol/L, and verified by SDA-PAGE and Western blot. In addition, the protein was purified with Ni-NTA agarose, and used to immunize mice,and the polyclonal antibody specifically bound to E. coli HtrA protein. The results will provide a theoretical basis for studying the roles of HtrA protein and developing vaccines for fur-bearing animals against E. coli.展开更多
文摘The ability to identify emotional arousal in heterospecific vocalizations may facilitate behaviors that increase survival opportunities. Crucially, this ability may orient inter-species interactions, par- ticularly between humans and other species. Research shows that humans identify emotional arousal in vocalizations across multiple species, such as cats, dogs, and piglets. However, no previ- ous study has addressed humans" ability to identify emotional arousal in silver foxes. Here, we adopted low- and high-arousal calls emitted by three strains of silver fox--Tame, Aggressive, and Unselected--in response to human approach. Tame and Aggressive foxes are genetically selected for friendly and attacking behaviors toward humans, respectively. Unselected foxes show aggres- sive and fearful behaviors toward humans. These three strains show similar levels of emotional arousal, but different levels of emotional valence in relation to humans. This emotional information is reflected in the acoustic features of the calls. Our data suggest that humans can identify high- arousal calls of Aggressive and Unselected foxes, but not of Tame foxes. Further analyses revealed that, although within each strain different acoustic parameters affect human accuracy in identifying high-arousal calls, spectral center of gravity, harmonic-to-noise ratio, and F0 best predict humans' ability to discriminate high-arousal calls across all strains. Furthermore, we identified in spectral center of gravity and F0 the best predictors for humans' absolute ratings of arousal in each call. Implications for research on the adaptive value of inter-specific eavesdropping are discussed.
基金Supported by China Spark Program(2015GA620002)Key Technologies Research and Development Program of Hebei Province(14826613D)+2 种基金PhD Start-up Fund of Hebei Normal University of Science and Technology(2015YB002)Scientific and Technological Research Program of Institutions of Higher Education of Hebei Province(ZD2016067)the Fund of Qinhuangdao Academy of Agricultural Sciences(2014-04)
文摘To investigate the roles of HtrA protein in bacterial adaption to stresses, htra gene was cloned from an Escherichia coli strain isolated from silver fox, double digested, and ligated into the prokaryotic expression vector pET32a. Then, the recombinant plasmid pET32a-htra was transformed into E. coli BL21 competent cells. The over-expression of His-HtrA protein was induced by the addition of IPTG at a final concentration of 1 mmol/L, and verified by SDA-PAGE and Western blot. In addition, the protein was purified with Ni-NTA agarose, and used to immunize mice,and the polyclonal antibody specifically bound to E. coli HtrA protein. The results will provide a theoretical basis for studying the roles of HtrA protein and developing vaccines for fur-bearing animals against E. coli.