英美地区居民一般都爱狗.中国有句成语“爱屋及乌”,英语里有一相似的说法“爱我及狗”(love me,love my dog).由此可见狗的地位较高.英美人士说话,常常人狗不分.如,“聪明伶俐的人”(clever dog),脾气粗暴的人(surly dog)等,均以相关...英美地区居民一般都爱狗.中国有句成语“爱屋及乌”,英语里有一相似的说法“爱我及狗”(love me,love my dog).由此可见狗的地位较高.英美人士说话,常常人狗不分.如,“聪明伶俐的人”(clever dog),脾气粗暴的人(surly dog)等,均以相关的形容词加“狗”表示.因此,对洋人的“凡狗(人)皆有得意日”(Every dog hashis day)的说法,便无可非议了.有人交好运,我们常说:“你真是个幸运儿”,而英美人士却说“你真是条幸运的狗”.[you are a lucky dog].展开更多
Sexual selection by female mating preference for male nuptial coloration has been suggested as a driving force in the rapid speciation of Lake Victoria cichlid fish. This process could have been facilitated or acceler...Sexual selection by female mating preference for male nuptial coloration has been suggested as a driving force in the rapid speciation of Lake Victoria cichlid fish. This process could have been facilitated or accelerated by genetic associations between female preference loci and male coloration loci. Preferences, as well as coloration, are heritable traits and are probably determined by more than one gene. However, little is known about potential genetic associations between these traits. In turbid water, we found a population that is variable in male nuptial coloration from blue to yellow to red. Males at the extreme ends of the phenotype distribution resemble a reproductively isolated species pair in clear water that has diverged into one species with blue-grey males and one species with bright red males. Females of the turbid water population vary in mating preference coinciding with the male phenotype distribution. For the current study, these females were mated to blue males. We measured the coloration of the sires and male offspring. Parents-offspring regression showed that the sires did not affect male offspring coloration, which confirms earlier findings that the blue species breeds true. In contrast, male offspring coloration was determined by the identity of the dams, which suggests that there is heritable variation in male color genes between females. However, we found that mating preferences of the dams were not correlated with male offspring coloration. Thus, there is no evidence for strong genetic linkage between mating preference and the preferred trait in this population [Current Zoology 56 （1）： 57-64 2010].展开更多
Under conditions of a warmer climate,the advance of the alpine treeline into alpine tundra has implications for carbon dynamics in mountain ecosystems.However,the above- and below-ground live biomass allocations among...Under conditions of a warmer climate,the advance of the alpine treeline into alpine tundra has implications for carbon dynamics in mountain ecosystems.However,the above- and below-ground live biomass allocations among different vegetation types within the treeline ecotones are not well investigated.To determine the altitudinal patterns of above-/below-ground carbon allocation,we measured the root biomass and estimated the above-ground biomass(AGB) in a subalpine forest,treeline forest,alpine shrub,and alpine grassland along two elevational transects towards the alpine tundra in southeast Tibet.The AGB strongly declined with increasing elevation,which was associated with a decrease in the leaf area index and a consequent reduction in carbon gain.The fine root biomass(FRB) increased significantly more in the alpine shrub and grassland than in the treeline forest,whereas the coarse root biomass changed little with increasing altitudes,which led to a stable below-ground biomass(BGB) value across altitudes.Warm and infertile soil conditions might explain the large amount of FRB in alpine shrub and grassland.Consequently,the root toshoot biomass ratio increased sharply with altitude,which suggested a remarkable shift of biomass allocation to root systems near the alpine tundra.Our findings demonstrate contrasting changes in AGB and BGB allocations across treeline ecotones,which should be considered when estimating carbon dynamics with shifting treelines.展开更多
The current paper presents the linguistic analysis of a Chinese greeting “nihao” in both literature and reality, and compares the practical use of “nihao” by both native and non-native Chinese speakers, which lead...The current paper presents the linguistic analysis of a Chinese greeting “nihao” in both literature and reality, and compares the practical use of “nihao” by both native and non-native Chinese speakers, which leads to a discussion of some existing problems observed in foreign language teaching and learning. The problems include overuse and overgeneralization of certain words and expressions, and lack of use of some others. These problems are caused by the deficient exposure to authentic (non-)linguistic setting. The study may provide a further understanding of the communicative method of teaching and learning a different language.展开更多
This paper presents an architecture of a hybrid recommender system in E-commerce environment. The goal of the system is to make special improvements in giving precisely personalized recommendation through some effecti...This paper presents an architecture of a hybrid recommender system in E-commerce environment. The goal of the system is to make special improvements in giving precisely personalized recommendation through some effective measures. Based on the study on the existing recommendation methods of both the conventional similarity function and the conventional feedback function, several improvement algorithms are developed to enhance the precision of recommendation, which include three improved similarity functions, four improved feedback functions, and adoption of both explicit and implicit preferences in individual user profile. Among them, issues and countermeasures of a new user, prominent preferences and long-term preferences are nicely addressed to gain better recommendation. The users preferences is so designed to be precisely captured by a user-side agent, and can make self-adjustment with explicit or implicit feedback.展开更多
文摘英美地区居民一般都爱狗.中国有句成语“爱屋及乌”,英语里有一相似的说法“爱我及狗”(love me,love my dog).由此可见狗的地位较高.英美人士说话,常常人狗不分.如,“聪明伶俐的人”(clever dog),脾气粗暴的人(surly dog)等,均以相关的形容词加“狗”表示.因此,对洋人的“凡狗(人)皆有得意日”(Every dog hashis day)的说法,便无可非议了.有人交好运,我们常说:“你真是个幸运儿”,而英美人士却说“你真是条幸运的狗”.[you are a lucky dog].
基金supported by the Netherlands Science Fotmdation (NWO-ALW 810.64.011)research grants from Leiden University Fundthe Schure-Beijerinck-Popping Foundation
文摘Sexual selection by female mating preference for male nuptial coloration has been suggested as a driving force in the rapid speciation of Lake Victoria cichlid fish. This process could have been facilitated or accelerated by genetic associations between female preference loci and male coloration loci. Preferences, as well as coloration, are heritable traits and are probably determined by more than one gene. However, little is known about potential genetic associations between these traits. In turbid water, we found a population that is variable in male nuptial coloration from blue to yellow to red. Males at the extreme ends of the phenotype distribution resemble a reproductively isolated species pair in clear water that has diverged into one species with blue-grey males and one species with bright red males. Females of the turbid water population vary in mating preference coinciding with the male phenotype distribution. For the current study, these females were mated to blue males. We measured the coloration of the sires and male offspring. Parents-offspring regression showed that the sires did not affect male offspring coloration, which confirms earlier findings that the blue species breeds true. In contrast, male offspring coloration was determined by the identity of the dams, which suggests that there is heritable variation in male color genes between females. However, we found that mating preferences of the dams were not correlated with male offspring coloration. Thus, there is no evidence for strong genetic linkage between mating preference and the preferred trait in this population [Current Zoology 56 （1）： 57-64 2010].
基金supported by the National Natural Science Foundation of China (41561011)the Natural Science Foundation of Jiangxi Province, China (20151BAB213029)
文摘Under conditions of a warmer climate,the advance of the alpine treeline into alpine tundra has implications for carbon dynamics in mountain ecosystems.However,the above- and below-ground live biomass allocations among different vegetation types within the treeline ecotones are not well investigated.To determine the altitudinal patterns of above-/below-ground carbon allocation,we measured the root biomass and estimated the above-ground biomass(AGB) in a subalpine forest,treeline forest,alpine shrub,and alpine grassland along two elevational transects towards the alpine tundra in southeast Tibet.The AGB strongly declined with increasing elevation,which was associated with a decrease in the leaf area index and a consequent reduction in carbon gain.The fine root biomass(FRB) increased significantly more in the alpine shrub and grassland than in the treeline forest,whereas the coarse root biomass changed little with increasing altitudes,which led to a stable below-ground biomass(BGB) value across altitudes.Warm and infertile soil conditions might explain the large amount of FRB in alpine shrub and grassland.Consequently,the root toshoot biomass ratio increased sharply with altitude,which suggested a remarkable shift of biomass allocation to root systems near the alpine tundra.Our findings demonstrate contrasting changes in AGB and BGB allocations across treeline ecotones,which should be considered when estimating carbon dynamics with shifting treelines.
文摘The current paper presents the linguistic analysis of a Chinese greeting “nihao” in both literature and reality, and compares the practical use of “nihao” by both native and non-native Chinese speakers, which leads to a discussion of some existing problems observed in foreign language teaching and learning. The problems include overuse and overgeneralization of certain words and expressions, and lack of use of some others. These problems are caused by the deficient exposure to authentic (non-)linguistic setting. The study may provide a further understanding of the communicative method of teaching and learning a different language.
文摘This paper presents an architecture of a hybrid recommender system in E-commerce environment. The goal of the system is to make special improvements in giving precisely personalized recommendation through some effective measures. Based on the study on the existing recommendation methods of both the conventional similarity function and the conventional feedback function, several improvement algorithms are developed to enhance the precision of recommendation, which include three improved similarity functions, four improved feedback functions, and adoption of both explicit and implicit preferences in individual user profile. Among them, issues and countermeasures of a new user, prominent preferences and long-term preferences are nicely addressed to gain better recommendation. The users preferences is so designed to be precisely captured by a user-side agent, and can make self-adjustment with explicit or implicit feedback.
