Harvestmen are a major arachnid order that has experienced a dramatic increase in biological knowledge in the 21st century.The publication of the book Harvestmen:The Biology of Opiliones in 2007 stimulated the develop...Harvestmen are a major arachnid order that has experienced a dramatic increase in biological knowledge in the 21st century.The publication of the book Harvestmen:The Biology of Opiliones in 2007 stimulated the development of many behavioral studies.Although the book is relatively recent,our understanding of the reproductive biology of harvestmen is already outdated due to the fast accumulation of new data.Our goal is to provide an updated review of the subject to serve as a benchmark for the following years.In the pre-copulatory phase,we explore the evolu-tion of facultative parthenogenesis,the factors that may affect the types of mating system,and the role of nuptial gifts in courtship.Regarding the copulatory phase,harvestmen are unique arachnids because they have aflagellate spermatozoa and a penis with complex morphology.We discuss the implications of these two features for sperm competition and cryptic female choice.In the post-copulatory phase,we connect ovi-position site selection and climate conditions to the widespread occurrence of resource defense polygyny,alternative reproductive tactics,and sexual dimorphism in several clades of tropical harvestmen.Finally,we present the different forms of parental care in the order,and discuss the benefits and costs of this behavior,which can be performed either by females or males.Throughout the review,we indicate gaps in our knowl-edge and subjects that deserve further studies.Hopefully,the information synthesized here will stimulate researchers worldwide to embrace harvestmen as a study system and to improve our effort to unravel the mysteries of their reproductive biology.展开更多
In addition to sperm,some accessory substances transferred to females during copulation act as nuptial gifts by passing on valuable nutrients in many insect species.The nutritional status of the males can thus have a ...In addition to sperm,some accessory substances transferred to females during copulation act as nuptial gifts by passing on valuable nutrients in many insect species.The nutritional status of the males can thus have a great effect on the mating behavior,fecundity and even the longevity of females.However,little is known about the effect of male nutritional status on the female reproductive traits in migratory insect species,particularly when females experience nutrient shortage and have to choose between reproduction and migration.Here,Cnaphalocrocis medinalis,a migratory rice pest in Asia,was studied to explore this issue.Our results showed that in male moths fed with honey solution,their gonads had higher energy content than gonads of starved males,resulting in increased energy content of the bursa copulatrix of females after mating with fed males.Such females showed increased mating frequency,fecundity and longevity compared to females mating with starved males,indicating that male moths deliver nuptial gifts to females and improve their reproductive performance.However,when females were starved,only about 45%mated,with just a single copulation,regardless of male nutritional status.Starved females showed lower fecundity,and a longer pre-oviposition period(indicating a greater propensity to migrate),compared to fed females.However,copulation still significantly extended their longevity.These results suggest that starved females invest in migration to escape deteriorating habitats,rather than investing the nuptial gift to increased fecundity.Our results further our understanding of the reproductive adaptability of migratory insects under conditions of food stress.展开更多
Background: The interaction between physicians and medical representatives (MRs) through gift offering is a common cause for conflicts of interest for physicians that negatively influence prescribing behaviors of phys...Background: The interaction between physicians and medical representatives (MRs) through gift offering is a common cause for conflicts of interest for physicians that negatively influence prescribing behaviors of physicians throughout the world. This study aimed to evaluate the interaction between MRs and Iraqi specialist physicians through the acceptance of MRs gifts and the effect of such acceptance on physician’s prescribing patterns. Methods: A survey in a questionnaire format for specialist physicians was done during March-October 2013 in Iraq, Baghdad. The questionnaire involves four major parts regarding the approximate number of patients and medical representatives, gift acceptance, medical conferences, and prescribing pattern. Results: In Iraq specialist physicians were visited by 1 - 3 MRs/day. 50% of the Iraqi physicians like to get the educational information by attending conferences outside Iraq. Regarding Gift acceptance, 41% of participated physicians showed a general acceptance to promotional gifts, and 91% of physicians accept low cost gifts but only 41% of them accept high cost recreational gifts. Free samples were used by 59% of Iraqi physicians to treat some people. 77% of physicians prefer prescribing new medications, while more than 95% of participated physicians stated that they stop prescribing these new drugs either due to their ineffectiveness or due to their side effects. On the other hand physicians significantly change their prescribing behavior through shifting not only among generic drugs, but also from brand to generic drugs in their prescriptions. Gift acceptance is directly correlated with such shift and change in prescribing behavior. Conclusion: Iraqi physicians accept various types of gifts from pharmaceutical companies;this can influence physician prescribing pattern and result in early adoption to prescribe newly medications depending on promotional information even in absence of clinical evidence about the drug effectiveness or side effects, which may result in undesirabl展开更多
Although Eileen Chang, one of China＇s most popular twentieth-century writers, never visited Nanyang （lit., the South Sea, referring principally to Southeast Asia）, Nanyang and huaqiao （Chinese sojourners） are men...Although Eileen Chang, one of China＇s most popular twentieth-century writers, never visited Nanyang （lit., the South Sea, referring principally to Southeast Asia）, Nanyang and huaqiao （Chinese sojourners） are mentioned frequently in her writings. This essay first analyzes Chang＇s images of Nanyang and huaqiao, and then discusses the societal and individual contexts of her literary conceptualizations by tracing her direct and indirect knowledge of these themes. Chang＇s imagination of Nanyang and huaqiao, examined within the historical context of Sino-Nanyang interactions, provides a valuable opportunity to discuss the emergence of a nationalist-driven huaqiao community and the expansion of Sino-Nanyanginteractions before the Pacific War.展开更多
文摘Harvestmen are a major arachnid order that has experienced a dramatic increase in biological knowledge in the 21st century.The publication of the book Harvestmen:The Biology of Opiliones in 2007 stimulated the development of many behavioral studies.Although the book is relatively recent,our understanding of the reproductive biology of harvestmen is already outdated due to the fast accumulation of new data.Our goal is to provide an updated review of the subject to serve as a benchmark for the following years.In the pre-copulatory phase,we explore the evolu-tion of facultative parthenogenesis,the factors that may affect the types of mating system,and the role of nuptial gifts in courtship.Regarding the copulatory phase,harvestmen are unique arachnids because they have aflagellate spermatozoa and a penis with complex morphology.We discuss the implications of these two features for sperm competition and cryptic female choice.In the post-copulatory phase,we connect ovi-position site selection and climate conditions to the widespread occurrence of resource defense polygyny,alternative reproductive tactics,and sexual dimorphism in several clades of tropical harvestmen.Finally,we present the different forms of parental care in the order,and discuss the benefits and costs of this behavior,which can be performed either by females or males.Throughout the review,we indicate gaps in our knowl-edge and subjects that deserve further studies.Hopefully,the information synthesized here will stimulate researchers worldwide to embrace harvestmen as a study system and to improve our effort to unravel the mysteries of their reproductive biology.
基金supported by the National Key Research and Development Program of China(2016YFD0300702)the Fundamental Research Funds for the Central Universities(China)(KJYQ201902,KJJQ201803).
文摘In addition to sperm,some accessory substances transferred to females during copulation act as nuptial gifts by passing on valuable nutrients in many insect species.The nutritional status of the males can thus have a great effect on the mating behavior,fecundity and even the longevity of females.However,little is known about the effect of male nutritional status on the female reproductive traits in migratory insect species,particularly when females experience nutrient shortage and have to choose between reproduction and migration.Here,Cnaphalocrocis medinalis,a migratory rice pest in Asia,was studied to explore this issue.Our results showed that in male moths fed with honey solution,their gonads had higher energy content than gonads of starved males,resulting in increased energy content of the bursa copulatrix of females after mating with fed males.Such females showed increased mating frequency,fecundity and longevity compared to females mating with starved males,indicating that male moths deliver nuptial gifts to females and improve their reproductive performance.However,when females were starved,only about 45%mated,with just a single copulation,regardless of male nutritional status.Starved females showed lower fecundity,and a longer pre-oviposition period(indicating a greater propensity to migrate),compared to fed females.However,copulation still significantly extended their longevity.These results suggest that starved females invest in migration to escape deteriorating habitats,rather than investing the nuptial gift to increased fecundity.Our results further our understanding of the reproductive adaptability of migratory insects under conditions of food stress.
文摘Background: The interaction between physicians and medical representatives (MRs) through gift offering is a common cause for conflicts of interest for physicians that negatively influence prescribing behaviors of physicians throughout the world. This study aimed to evaluate the interaction between MRs and Iraqi specialist physicians through the acceptance of MRs gifts and the effect of such acceptance on physician’s prescribing patterns. Methods: A survey in a questionnaire format for specialist physicians was done during March-October 2013 in Iraq, Baghdad. The questionnaire involves four major parts regarding the approximate number of patients and medical representatives, gift acceptance, medical conferences, and prescribing pattern. Results: In Iraq specialist physicians were visited by 1 - 3 MRs/day. 50% of the Iraqi physicians like to get the educational information by attending conferences outside Iraq. Regarding Gift acceptance, 41% of participated physicians showed a general acceptance to promotional gifts, and 91% of physicians accept low cost gifts but only 41% of them accept high cost recreational gifts. Free samples were used by 59% of Iraqi physicians to treat some people. 77% of physicians prefer prescribing new medications, while more than 95% of participated physicians stated that they stop prescribing these new drugs either due to their ineffectiveness or due to their side effects. On the other hand physicians significantly change their prescribing behavior through shifting not only among generic drugs, but also from brand to generic drugs in their prescriptions. Gift acceptance is directly correlated with such shift and change in prescribing behavior. Conclusion: Iraqi physicians accept various types of gifts from pharmaceutical companies;this can influence physician prescribing pattern and result in early adoption to prescribe newly medications depending on promotional information even in absence of clinical evidence about the drug effectiveness or side effects, which may result in undesirabl
文摘Although Eileen Chang, one of China＇s most popular twentieth-century writers, never visited Nanyang （lit., the South Sea, referring principally to Southeast Asia）, Nanyang and huaqiao （Chinese sojourners） are mentioned frequently in her writings. This essay first analyzes Chang＇s images of Nanyang and huaqiao, and then discusses the societal and individual contexts of her literary conceptualizations by tracing her direct and indirect knowledge of these themes. Chang＇s imagination of Nanyang and huaqiao, examined within the historical context of Sino-Nanyang interactions, provides a valuable opportunity to discuss the emergence of a nationalist-driven huaqiao community and the expansion of Sino-Nanyanginteractions before the Pacific War.
