Background:Parrots(Psittacidae Family)are one of the most colorful groups of birds in the world,their colors pro-duced both structurally and via unusual pigments(psittacofulvins).Most species are considered to be mono...Background:Parrots(Psittacidae Family)are one of the most colorful groups of birds in the world,their colors pro-duced both structurally and via unusual pigments(psittacofulvins).Most species are considered to be monogamous,and many have been viewed historically as sexually monomorphic and monochromatic.However,studies using morphometric analysis and spectrophotometric techniques have revealed sexual size dimorphism and also sexual plumage color dimorphism among some species.The Monk Parakeet(Myiopsitta monachus),a native parrot of South America,is an interesting species for the study of plumage coloration and size since it is considered sexually mono-chromatic and monomorphic.Furthermore,recent studies show that the Monk Parakeet has extra-bond paternity behavior and even breeding trios,which suggests that sexual selection may play an important role in this species,and that it might have sexually dimorphic plumage(albeit imperceptible by humans)and be dimorphic in size.Methods:For the determination of plumage color we used spectrophotometry in the range of avian vision(300-700 nm)and performed a morphological analysis.Results:Our spectrophotometric results indicate that the Monk Parakeet shows subtle sexual plumage color dimor-phism in three(crown,nape and wing)out of twelve body regions.Similarly,our morphometric analysis showed that there are subtle sex differences in body size(bill and weight).Conclusions:Although the Monk Parakeet shows extra-bond paternity and breeding trio behaviors which could increase sexual dimorphism,these behaviors occur among highly related individuals;perhaps the high rate of inbreeding is responsible for the attenuation of sexual plumage color dimorphism and sex differences in body size observed.展开更多
性描写是许多经典文学作品的重要组成部分。但在文学翻译中,这样的描写往往被删除或做淡化处理,而且这样的处理方法还得到了翻译学者们的支持,理由是我国传统的性伦理容忍不了这些描写。可是在中国文学中,类似的性描写早已屡见不鲜,其...性描写是许多经典文学作品的重要组成部分。但在文学翻译中,这样的描写往往被删除或做淡化处理,而且这样的处理方法还得到了翻译学者们的支持,理由是我国传统的性伦理容忍不了这些描写。可是在中国文学中,类似的性描写早已屡见不鲜,其艺术价值也得到了普遍的肯定。对The Color Purple的两个汉译本的分析表明,译者或出版商对性伦理的理解并不正确。他们对性描写加以特殊处理,是出于对性禁忌的顾虑。展开更多
Barn Swallows(Hirundo rustica), a group of passerine birds comprised of six closely related subspecies, are well known throughout their nearly worldwide distribution, in part because of their close association with hu...Barn Swallows(Hirundo rustica), a group of passerine birds comprised of six closely related subspecies, are well known throughout their nearly worldwide distribution, in part because of their close association with human settlements.A tractable species for both individual-based and population-level studies, Barn Swallows are a prominent model system in evolutionary, ecological, and behavioral research. Here we review work on sexual selection and population divergence in this species complex, focusing on comparative studies among populations and subspecies.We summarize variation in the targets of mate choice and in the information conveyed by sexually selected traits, and conclude that the benefits advertised by different traits may vary geographically. Finally, we consider the role of sexual selection as a driver of population divergence in this widespread and phenotypically variable species complex.展开更多
Aim: Erectile dysfunction may be observed in up to 80% of patients with Peyronie's disease. An objective evaluation of the erectile function is attempted to work out in patients with Peyronie's disease. Method...Aim: Erectile dysfunction may be observed in up to 80% of patients with Peyronie's disease. An objective evaluation of the erectile function is attempted to work out in patients with Peyronie's disease. Methods: Penile deformity, sexual function and penile vascular status were analyzed in 123 patients with Peyronie's disease, who had not received any pertinent treatment. Results: Penile deformity, palpable plaque and pain on erection were seen in 112 (91%), 97(78.8%) and 27 (21.9%) of the 123 patients, respectively. Of the 76 patients evaluated by color Doppler ultrasounography, veno-occlusive dysfunction as the vascular component for erectile dysfunction was found in 17 (22.3%), arterial insufficiency in 10(13.1%) and a mixed picture in 23 (30.2%). Conclusion: The documentation of penile erectile function and the determination of the vascular status using color Doppler ultrasonography can guide the appropriate therapeutic choice.展开更多
文摘Background:Parrots(Psittacidae Family)are one of the most colorful groups of birds in the world,their colors pro-duced both structurally and via unusual pigments(psittacofulvins).Most species are considered to be monogamous,and many have been viewed historically as sexually monomorphic and monochromatic.However,studies using morphometric analysis and spectrophotometric techniques have revealed sexual size dimorphism and also sexual plumage color dimorphism among some species.The Monk Parakeet(Myiopsitta monachus),a native parrot of South America,is an interesting species for the study of plumage coloration and size since it is considered sexually mono-chromatic and monomorphic.Furthermore,recent studies show that the Monk Parakeet has extra-bond paternity behavior and even breeding trios,which suggests that sexual selection may play an important role in this species,and that it might have sexually dimorphic plumage(albeit imperceptible by humans)and be dimorphic in size.Methods:For the determination of plumage color we used spectrophotometry in the range of avian vision(300-700 nm)and performed a morphological analysis.Results:Our spectrophotometric results indicate that the Monk Parakeet shows subtle sexual plumage color dimor-phism in three(crown,nape and wing)out of twelve body regions.Similarly,our morphometric analysis showed that there are subtle sex differences in body size(bill and weight).Conclusions:Although the Monk Parakeet shows extra-bond paternity and breeding trio behaviors which could increase sexual dimorphism,these behaviors occur among highly related individuals;perhaps the high rate of inbreeding is responsible for the attenuation of sexual plumage color dimorphism and sex differences in body size observed.
文摘性描写是许多经典文学作品的重要组成部分。但在文学翻译中,这样的描写往往被删除或做淡化处理,而且这样的处理方法还得到了翻译学者们的支持,理由是我国传统的性伦理容忍不了这些描写。可是在中国文学中,类似的性描写早已屡见不鲜,其艺术价值也得到了普遍的肯定。对The Color Purple的两个汉译本的分析表明,译者或出版商对性伦理的理解并不正确。他们对性描写加以特殊处理,是出于对性禁忌的顾虑。
基金Support was provided by the National Science Foundation (DEB-CAREER 1149942 to RJS)
文摘Barn Swallows(Hirundo rustica), a group of passerine birds comprised of six closely related subspecies, are well known throughout their nearly worldwide distribution, in part because of their close association with human settlements.A tractable species for both individual-based and population-level studies, Barn Swallows are a prominent model system in evolutionary, ecological, and behavioral research. Here we review work on sexual selection and population divergence in this species complex, focusing on comparative studies among populations and subspecies.We summarize variation in the targets of mate choice and in the information conveyed by sexually selected traits, and conclude that the benefits advertised by different traits may vary geographically. Finally, we consider the role of sexual selection as a driver of population divergence in this widespread and phenotypically variable species complex.
文摘Aim: Erectile dysfunction may be observed in up to 80% of patients with Peyronie's disease. An objective evaluation of the erectile function is attempted to work out in patients with Peyronie's disease. Methods: Penile deformity, sexual function and penile vascular status were analyzed in 123 patients with Peyronie's disease, who had not received any pertinent treatment. Results: Penile deformity, palpable plaque and pain on erection were seen in 112 (91%), 97(78.8%) and 27 (21.9%) of the 123 patients, respectively. Of the 76 patients evaluated by color Doppler ultrasounography, veno-occlusive dysfunction as the vascular component for erectile dysfunction was found in 17 (22.3%), arterial insufficiency in 10(13.1%) and a mixed picture in 23 (30.2%). Conclusion: The documentation of penile erectile function and the determination of the vascular status using color Doppler ultrasonography can guide the appropriate therapeutic choice.
