Comparative analyses were conducted to compare the effects of the behavioral characteristics of the drivers of taxis and private cars on the capacity and safety of signalized intersections. Data were collected at sixt...Comparative analyses were conducted to compare the effects of the behavioral characteristics of the drivers of taxis and private cars on the capacity and safety of signalized intersections. Data were collected at sixteen signalized intersections in the Nanjing area in China. The risk-taking behaviors of the drivers of taxis and private cars were compared. The results suggest that 19.9% of taxi drivers have committed at least one of the identified risky behaviors, which is 2.37 times as high as that of the drivers of private cars(8.4%). The traffic conflicts technique was used to estimate the safety effects of taxis and private cars. The overall conflict rate for taxis is 21.4% higher than that for private cars, implying that taxis are more likely to be involved in conflicts. Almost all of the identified traffic conflicts can be attributed to certain levels of risk-taking behaviors committed by either taxi drivers or the drivers of private cars, and taxi drivers are more likely to be at fault in a conflict. Failure to yield to right-of-way and improper lane change is the leading causes of the conflicts in which taxis are at-fault. The research team further studied the effects of taxis on the queue discharge characteristics at signalized intersections. The results show that the presence of taxis significantly reduces both start-up lost time and saturation headways. The effects of taxis on saturation flow rates are dependent on the proportion of taxis in the discharge flow, and the saturation flow rates increase with the increase in the proportion of taxis. The adjustment factors for various proportions of taxis for different turning movements are then calculated to quantitatively evaluate the effects of taxis on the capacity of signalized intersections.展开更多
Turkish Van and Angora cats are one of most important genetic resources in Turkey. The study aimed to evaluate some morphological properties and also behavioural characteristics in both Turkish Van and Angora cats. Th...Turkish Van and Angora cats are one of most important genetic resources in Turkey. The study aimed to evaluate some morphological properties and also behavioural characteristics in both Turkish Van and Angora cats. This research used both literature and the records from the Van Cat Home at Van Cats Research Centre of Yuzuncu Yil University for Turkish Van cats, as well as literature information for Turkish Angora cat. Van cats which have a special place among world cat races have gained appreciation of people with their original eye colors, long white hair and affectionate attitudes. Origin of Turkish Angora cat breeding in Turkey is Ankara province. Angora cat is strong, energetic, kind, known as a moderately long silky haired cat. According to the results of this study and literature, withers height and body length of Turkish Van cat are higher than the Turkish Angora cat, while tale length and breast girth of Turkish Angora cat are higher than the Turkish Van cat. Body weight (g) of female Turkish Angora cat is heavier than the Turkish Van cat, but male Turkish Van cat is heavier than Turkish Angora cat.展开更多
Sexual isolation resulting from differences in mate choice behaviors is a hallmark of rapidly-speciating lineages. When present, asymmetrical sexual isolation may provide insights into the mechanisms responsible for t...Sexual isolation resulting from differences in mate choice behaviors is a hallmark of rapidly-speciating lineages. When present, asymmetrical sexual isolation may provide insights into the mechanisms responsible for the evolutionary change in mate signaling traits. In particular, Kaneshiro's hypothesis suggests that divergence in sexual characters between populations may arise in allopatry when 'derived' founding populations are subject to severe population bottlenecks, accompanied by a relaxation of sexual selection relative to 'ancestral' source populations. In the present study, we tested predictions of asymmetrical sexual isolation between two allopatric species of Hawaiian Laupala crickets, representing 'ancestral' (L. makaio) and 'derived' (L. nigra) taxa. While crickets in this genus are notable for rapid divergence of male courtship songs, these species share similar song types, thus suggesting that patterns of sexual isolation are likely due to other mating cues. Analysis of behavioral responses in conspeci- fic and heterospecific 'no-choice' mating trials revealed pronounced asymmetrical isolation in the direction predicted by Kane- shiro's hypothesis, wherein we observed a significant reduction in mating success for crosses involving 'derived' males paired with 'ancestral' females, compared to the reciprocal heterospecific and both conspecific pairings. Further dissection of courtship behaviors suggested this difference did not reflect male mate choice, but rather, marked reduced spermatophore acceptance rates by 'ancestral' females paired with 'derived' males. The results are discussed with respect to founder effect models of speciatiou and the potential role of chemosensory signals in mate choice in these species [Current Zoology 59 (2): 230-238, 2013].展开更多
基金Projects(51322810,50908050)supported by the National Natural Science Foundation of China
文摘Comparative analyses were conducted to compare the effects of the behavioral characteristics of the drivers of taxis and private cars on the capacity and safety of signalized intersections. Data were collected at sixteen signalized intersections in the Nanjing area in China. The risk-taking behaviors of the drivers of taxis and private cars were compared. The results suggest that 19.9% of taxi drivers have committed at least one of the identified risky behaviors, which is 2.37 times as high as that of the drivers of private cars(8.4%). The traffic conflicts technique was used to estimate the safety effects of taxis and private cars. The overall conflict rate for taxis is 21.4% higher than that for private cars, implying that taxis are more likely to be involved in conflicts. Almost all of the identified traffic conflicts can be attributed to certain levels of risk-taking behaviors committed by either taxi drivers or the drivers of private cars, and taxi drivers are more likely to be at fault in a conflict. Failure to yield to right-of-way and improper lane change is the leading causes of the conflicts in which taxis are at-fault. The research team further studied the effects of taxis on the queue discharge characteristics at signalized intersections. The results show that the presence of taxis significantly reduces both start-up lost time and saturation headways. The effects of taxis on saturation flow rates are dependent on the proportion of taxis in the discharge flow, and the saturation flow rates increase with the increase in the proportion of taxis. The adjustment factors for various proportions of taxis for different turning movements are then calculated to quantitatively evaluate the effects of taxis on the capacity of signalized intersections.
文摘Turkish Van and Angora cats are one of most important genetic resources in Turkey. The study aimed to evaluate some morphological properties and also behavioural characteristics in both Turkish Van and Angora cats. This research used both literature and the records from the Van Cat Home at Van Cats Research Centre of Yuzuncu Yil University for Turkish Van cats, as well as literature information for Turkish Angora cat. Van cats which have a special place among world cat races have gained appreciation of people with their original eye colors, long white hair and affectionate attitudes. Origin of Turkish Angora cat breeding in Turkey is Ankara province. Angora cat is strong, energetic, kind, known as a moderately long silky haired cat. According to the results of this study and literature, withers height and body length of Turkish Van cat are higher than the Turkish Angora cat, while tale length and breast girth of Turkish Angora cat are higher than the Turkish Van cat. Body weight (g) of female Turkish Angora cat is heavier than the Turkish Van cat, but male Turkish Van cat is heavier than Turkish Angora cat.
文摘Sexual isolation resulting from differences in mate choice behaviors is a hallmark of rapidly-speciating lineages. When present, asymmetrical sexual isolation may provide insights into the mechanisms responsible for the evolutionary change in mate signaling traits. In particular, Kaneshiro's hypothesis suggests that divergence in sexual characters between populations may arise in allopatry when 'derived' founding populations are subject to severe population bottlenecks, accompanied by a relaxation of sexual selection relative to 'ancestral' source populations. In the present study, we tested predictions of asymmetrical sexual isolation between two allopatric species of Hawaiian Laupala crickets, representing 'ancestral' (L. makaio) and 'derived' (L. nigra) taxa. While crickets in this genus are notable for rapid divergence of male courtship songs, these species share similar song types, thus suggesting that patterns of sexual isolation are likely due to other mating cues. Analysis of behavioral responses in conspeci- fic and heterospecific 'no-choice' mating trials revealed pronounced asymmetrical isolation in the direction predicted by Kane- shiro's hypothesis, wherein we observed a significant reduction in mating success for crosses involving 'derived' males paired with 'ancestral' females, compared to the reciprocal heterospecific and both conspecific pairings. Further dissection of courtship behaviors suggested this difference did not reflect male mate choice, but rather, marked reduced spermatophore acceptance rates by 'ancestral' females paired with 'derived' males. The results are discussed with respect to founder effect models of speciatiou and the potential role of chemosensory signals in mate choice in these species [Current Zoology 59 (2): 230-238, 2013].