Asymmetric allylic C—H functionalization is a valuable and challenging research area. Different from the conventional direct allylic C—H cleavage strategy, transition metal-catalyzed migratory allylic substitution o...Asymmetric allylic C—H functionalization is a valuable and challenging research area. Different from the conventional direct allylic C—H cleavage strategy, transition metal-catalyzed migratory allylic substitution of remote dienes has emerged as a new route to achieve allylic C—H functionalization enantioselectively. This review provides a detailed summary of the development and advance of this strategy, introduces the related mechanistic processes, and discusses the area based on the types of catalysts and products.展开更多
Bergmann's rule predicts that the larger of two homeotherm species differing only in size would occur at higher latitudes, or in cooler climates than the smaller, because of relative thermoregulatory costs in rela...Bergmann's rule predicts that the larger of two homeotherm species differing only in size would occur at higher latitudes, or in cooler climates than the smaller, because of relative thermoregulatory costs in relation to body mass/surface area ratio. Individual tracking data from two congeneric long-distance migratory northern nesting swan species, Tundra Cygnus columbianus (TS, n = 99) and Whooper Swans C. cygnus (WS, 61–71% larger mass than TS, n = 47) were used to determine their summering and wintering latitudes along similar migration routes and common staging areas along the same flyway. We hypothesised that throughout Arctic and Boreal breeding areas (10℃ in July), summer ambient temperatures mainly exceed the Lower Critical Temperatures (LCT, c. 1℃) for both swan species, so the duration of the snow-free summer period will favour smaller body size at highest latitudes, since this constrains the time available to lay, incubate eggs and raise cygnets to fledging. We hypothesised that in contrast, in winter, both species occur in temperatures near to freezing (−3℃ in January), below their respective LCT, so differential thermoregulation demands would constrain TS to winter south of WS. Tracking of individuals showed for the first time that while smaller TS summered significantly north of WS, WS wintered significantly north of TS, with limited overlap in both seasons. We conclude that differences in relative summer distribution of these two closely related migratory herbivores are not to do with latitude per se but are constrained by the time both species require to raise their young to fledging during the short northern summer, when thermoregulation costs are unlikely limiting. In winter, both swan species occur within a climate envelop at or below their respective LCT and smaller TS occurred consistently south of the range of the tracked WS, as predicted by Bergmann's rule.展开更多
Double bonds of internal olefins can be efficiently migrated to the terminal carbons and regioselectively hydroesterified with formates in the presence of Pd(OAc)_(2) and 1,2-DTBPMB under mild reaction conditions,prov...Double bonds of internal olefins can be efficiently migrated to the terminal carbons and regioselectively hydroesterified with formates in the presence of Pd(OAc)_(2) and 1,2-DTBPMB under mild reaction conditions,providing a wide variety of corresponding linear carboxylic esters bearing various functional groups in good yields and>20:1 linear/branch ratios.The reaction is optionally simple and does not need to use CO gas and acid co-catalysts.展开更多
Background: The motivation of birds to proceed with migration is associated with both endogenous and exogenous factors. According to their migratory situation and to the characteristics of stopover sites, birds might ...Background: The motivation of birds to proceed with migration is associated with both endogenous and exogenous factors. According to their migratory situation and to the characteristics of stopover sites, birds might exhibit migratory motivation differently among sites. Although migratory motivation of migrating birds has been well studied in many species, the investigation of the same species in different migratory situations and at different stopover sites is still limited. We predicted that birds at different stopover sites could differ in migratory disposition, including expression of migratory restlessness and responses to environmental cues.Methods: Here we compared migration motivation and orientation of Great Knots(Calidris tenuirostris) at two stopo ver sites, Chongming Dongtan in the south Yellow Sea, which is a temporary rest site, and Yalujiang Estuary Wetland in the north Yellow Sea, which is a critical refuelling site, during northward migration. Modified Emlen funnels, with thermal paper inside to record scratches of the birds, were used to detect activity(intensity and direction) of birds. Environmental conditions, including wind direction and speed, cloud cover, tide condition, times of the day(before and after sunset) were recorded during experiments. Generalized linear models were used to detect the effects of endogenous and exogenous factors on the migratory motivation of the birds.Results: In the south Yellow Sea, the migratory activity intensity of Great Knots was positively related to wind assistance. In the north Yellow Sea, where birds exhibited higher intensity of migratory activity than in the south, the intensity increased and the motivation to initiate migration grew stronger as the season advanced. The Great Knots exhibited wind-related orientation behaviour in the funnels at both sites.Conclusions: The results suggest that the intensity of migratory motivation differed between the two sites. Departure decisions of Great Knots appear to be affected mainly by external factors at the temporary rest site in the south Yellow Sea but possibly by endogenous factors at the final pre-breeding refuelling site in the north Yellow Sea.展开更多
Increasing human activities have contributed to global climate change, and thus resulted in a downward trend in the number of species and population sizes of migratory birds. This trend is closely related to a reducti...Increasing human activities have contributed to global climate change, and thus resulted in a downward trend in the number of species and population sizes of migratory birds. This trend is closely related to a reduction in habitat size and lower habitat quality. The Poyang Lake wetland in China constitutes one of Asia's largest overwintering habitats for migratory birds. Over the past 10 years, restoration projects have improved the habitat ecology of these wetlands. In this study, we assessed the changes in habitat quality for overwintering migratory birds from 2000 to 2012 near two villages in the Poyang Lake wetland using the In VEST model. Average habitat quality for migratory birds has been improved by 18.8% and47.7%. Differences in the degrees of habitat improvement can be attributed to differences in the change of habitat size and in the impact of threat sources that resulted from the combined effects of restoration and human activities in these two villages.展开更多
A novel Clade 2.3.2.1c H5N1 reassortant virus caused several outbreaks in wild birds in some regions of China from late 2014 to 2015.Based on the genetic and phylogenetic analyses,the viruses possess a stable gene con...A novel Clade 2.3.2.1c H5N1 reassortant virus caused several outbreaks in wild birds in some regions of China from late 2014 to 2015.Based on the genetic and phylogenetic analyses,the viruses possess a stable gene constellation with a Clade 2.3.2.1c HA,a H9N2-derived PB2 gene and the other six genes of Asian H5N1-origin.The Clade 2.3.2.1c H5N1 reassortants displayed a high genetic relationship to a human H5N1 strain(A/Alberta/01/2014).Further analysis showed that similar viruses have been circulating in wild birds in China,Russia,Dubai(Western Asia),Bulgaria and Romania(Europe),as well as domestic poultry in some regions of Africa.The affected areas include the Central Asian,East Asian-Australasian,West Asian-East African,and Black Sea/Mediterranean flyways.These results show that the novel Clade 2.3.2.1c reassortant viruses are circulating worldwide and may have gained a selective advantage in migratory birds,thus posing a serious threat to wild birds and potentially humans.展开更多
In this study, the Bt-transgenic and non-transgenic rice were fed to three generations of oriental migratory Iocust, respectiveIy under Iaboratory conditions so as to investigate the effects of Bt-transgenic rice on c...In this study, the Bt-transgenic and non-transgenic rice were fed to three generations of oriental migratory Iocust, respectiveIy under Iaboratory conditions so as to investigate the effects of Bt-transgenic rice on coId resistance of oriental migratory Iocust. The supercooIing point and freezing point of oriental migratory Iocust was de-termined using supercooIing point meter. The resuIts showed that the supercooIing points of fourth instar Iarvae, fifth instar Iarvae, male aduIts and female aduIts, which were al fed with Bt-transgenic rice, were -5.89, -7.59, -6.64 and -6.79, respectiveIy. There were no significant differences between treatment and controI groups.展开更多
New neurons are integrated into the circuitry of the olfactory bulb throughout the lifespan in the mamma- lian brain--including in humans. These new neurons are born in the subventricular zone and subsequently mature ...New neurons are integrated into the circuitry of the olfactory bulb throughout the lifespan in the mamma- lian brain--including in humans. These new neurons are born in the subventricular zone and subsequently mature as they are guided over long distances via the rostral migratory stream through mechanisms we are only just beginning to understand. Regeneration after brain injury is very limited, and although some neuroblasts from the rostral migratory stream will leave the path and migrate toward cortical lesion sites, this neuronal replacement is generally not sustained and therefore does not provide enough new neurons to alleviate functional deficits. Using newly discovered microtissue engineering techniques, we have built the first self-contained, implantable constructs that mimic the architecture and function of the rostral migratory stream. This engineered microtissue emulates the dense cord-like bundles of astrocytic somata and processes that are the hallmark anatomical feature of the glial tube. As such, our living microtissue-en- gineered rostral migratory stream can serve as an in vitro test bed for unlocking the secrets of neuroblast migration and maturation, and may potentially serve as a living transplantable construct derived from a patient＇s own cells that can redirect their own neuroblasts into lesion sites for sustained neuronal replace- ment following brain injury or neurodegenerative disease. In this paper, we summarize the development of fabrication methods for this microtissue-engineered rostral migratory stream and provide proof-of-princi- ple evidence that it promotes and directs migration of immature neurons.展开更多
One possible hypothesis for the function of post-fledging dispersal is to locate a suitable future breeding area.This post-fledging period may be particularly important in migratory species because they have a limited...One possible hypothesis for the function of post-fledging dispersal is to locate a suitable future breeding area.This post-fledging period may be particularly important in migratory species because they have a limited period to gather information prior to autumn migration,and in protandrous species,males must quickly acquire a territory after returning from spring migration to maximize their fitness.Here we use color-ring resightings to investigate how the post-fledging dispersal movements of the Cyprus wheatear Oenanthe cypriaca,a small migratory passerine,relate to their first breeding territory the following year when they return from migration.We found that males established first breeding territories that were significantly closer to their post-fledging location than to their natal sites or to post-fledging locations of other conspecifics,but these patterns were not apparent in females.Our findings suggest that familiarity with potential breeding sites may be important for juveniles of migratory species,particularly for the sex that acquires and advertises breeding territories.Exploratory dispersal prior to a migrant’s first autumn migration may contribute toward its breeding success the following year,further highlighting the importance of early seasonal breeding on fitness and population dynamics more generally.展开更多
Japanese Spanish mackerel,Scomberomorus niphonius,is a commercially important,highly migratory species that is widely distributed throughout the northwestern Pacific region.However,its life history and migratory patte...Japanese Spanish mackerel,Scomberomorus niphonius,is a commercially important,highly migratory species that is widely distributed throughout the northwestern Pacific region.However,its life history and migratory patterns are only partially understood.This study used otolith chemistry to investigate the migratory pattern of S.niphonius in the southern Yellow Sea,an important fishing ground.Transverse sections of otoliths from 15 age-1 spawning or spent individuals,comprising up to one complete migration cycle,were analyzed from the core to the margin by using laser ablation inductively coupled plasma mass spectrometry.The ratios of the element to Ca were integrated with microstructural analysis to produce age-related elemental profiles.Combining multielemental analysis of otolith composition with multivariate analytical models,we quantified structural changes in otolith chemistry profiles.Results revealed there were diverse changing patterns of otolith chemistry profiles for detected elements and the elements of Na,Mg,Sr and Ba were important for the chronological signal.Five clusters were identified through chronological clustering,representing the five life stages from the early stage to the spawning stage.Variation of Ba:Ca ratio was most informative,showing a step-decreasing pattern in the first four stages and a rebound in the spawning stage.These results support the hypothesized migratory pattern of S.niphonius:hatching and spending their early life in the coastal sandy ridges system of the southern Yellow Sea,migrating northeastward and offshore for feeding during juvenile stage,aggregating in early October and migrating outward to the Jeju Island for wintering,and returning to the coastal waters for spawning.This study demonstrated the value of life-history related otolith chemistry profiles combined with multivariate analytical models was a means to verify the migration patterns of S.niphonius at regional scales with potential application in fisheries assessment and management.展开更多
[Objective] The research aimed to study influences of the weather and climate on wintering migratory bird in Dongting Lake. [Method] Bird analysis data provided by East Dongting Lake National Nature Reserve and winter...[Objective] The research aimed to study influences of the weather and climate on wintering migratory bird in Dongting Lake. [Method] Bird analysis data provided by East Dongting Lake National Nature Reserve and wintering migratory bird monitoring data in big and small west lakes in recent 5 years were used. By combing water level data and various meteorological factors in Chenglingji, wintering migratory bird in Dongting Lake was analyzed. [Result] Abnormal precipitation led to drought or flood in Dongting Lake, causing significant adverse effect on the birds. Abnormal climate was important reason for that wintering migratory bird greatly reduced, such as high temperature and later going south of the strong cold air. Extreme weather and climate events led that some birds in Dongting Lake significantly reduced. Meteorological element had certain influence to bird survey. We should select a reasonable investigation time based on weather and climate. In Birding Festival, weather had little effect on bird species observation. In the migratory season of bird, we could see many birds in fine cold weather after a strong cold air, which suitable for observing bird. When it was low temperature or less rain in autumn, and was high temperature or more rain and sunshine in early winter, it was suitable for migratory birds wintering in Dongting Lake. Ardea cinerea, Anser fabalis and Anser erythropus were more in sunny days while Phalacrocorax carbo was more in rainy weather. Grus grus was more in heavy wind weather while Recurvirostra avosetta was more in small wind weather. [Conclusion] The research provided scientific basis for studying migratory bird in east Dongting Lake.展开更多
I divide the rural households into three types:the rural households unwilling to move;the floating rural households;the migratory rural households.Through questionnaire survey of the married housewives in Anhui Provin...I divide the rural households into three types:the rural households unwilling to move;the floating rural households;the migratory rural households.Through questionnaire survey of the married housewives in Anhui Province and Zhejiang Province,I conduct comparative analysis of income and expenditure,change in the status of family members,the couple's housework time,the wives' will to settle in the city and attitude towards life,related to these three types of rural households.Results show that promoting wives' educational level and monthly family income will significantly make the wives in households unwilling to move,have stronger desire to make their children settle in the city;the housework time of the wives in the floating households is 3.4 times that of their husbands,the monthly income of the husbands in the floating households is significantly lower than that of the husbands in the migratory households,with heavy family burden assessed by themselves;the age of the wives in the migratory households is the smallest,and the educational level and income of them are the highest,but the monthly expenditure has not yet significantly expanded,and at the same time,the migratory households have the weakest desire to settle in the city.The recommendations concerning these three types of rural households are put forward as follows:promoting the skills of the members in the households unwilling to move,in agricultural cultivation,development of agricultural products and circulation of agricultural products;paying close attention to the floating rural households;promoting the government,enterprise,households to work together to stabilize the migratory households.展开更多
What has really happened in Europe since 2014?Why in 2018 are so many migrants still making their way towards Europe?For the first time since the Second World War,an important number of individuals have entered into E...What has really happened in Europe since 2014?Why in 2018 are so many migrants still making their way towards Europe?For the first time since the Second World War,an important number of individuals have entered into European soil.The idea for this article goes back to October 2015 when the prefet from the town where I live went in search of asylum seekers.This is what sparked off my inquiry amongst about 50 exiles housed in the annex of the Montmorency(95)hospital in July 2015.But against popular belief,migrants are not accepted fairly into countries,and the geographical distribution of Syrians in Turkey,Lebanon,Jordan,and Europe is contrary to what Kant had defended as a“right to visit”.Although the majority of researchers suggest welcoming migrants,it is necessary to reconsider some methodological and epistemological aspects and get away from some wrongly perceived concepts which dated prior to the year 2000.Yet,the Arab Spring has showed that we are dealing with unfinished post-colonialism,something that we will soon come back to in another article where we will propose another solution.展开更多
Impact statementThis study identifies avian tuberculosis as a potential cause of mass mortality in wild migratory birds in Inner Mongolia,China.Combining meta-transcriptomic sequencing and histopathological analysis,it...Impact statementThis study identifies avian tuberculosis as a potential cause of mass mortality in wild migratory birds in Inner Mongolia,China.Combining meta-transcriptomic sequencing and histopathological analysis,it reveals one of the rare instances oftuberculosis-associated outbreaks in avian populations.Thesefindings underscore the importance of surveillance on wildlifediseases to mitigate the risk of interspecies transmission of the disease associated pathogens and their broader implicationsfor biodiversity and public health.展开更多
Acute liver failure(ALF)is the onset of severe liver injury without pre-existing chronic liver diseases.12 The most common type of drug-induced ALF is caused by acetaminophen(APAP)overdose,which accounts for 45.7%of A...Acute liver failure(ALF)is the onset of severe liver injury without pre-existing chronic liver diseases.12 The most common type of drug-induced ALF is caused by acetaminophen(APAP)overdose,which accounts for 45.7%of ALF cases in the US.2 In severe cases of ALF,liver transplantation remains the only curative option.12 Nonetheless,there is currently a shortage of liver donor organs available to meet the demands for liver transplantation needed to save the lives of patients with ALF.Due to the increasing prevalence of metabolic dysfunction-associated steatotic liver disease and metabolic and alcohol-associated liver disease,34 many steatotic livers are discarded,further exacerbating the burden of liver shortages.Therefore,it is crucial to find therapeutic approaches that can potentially alleviate APAP-induced ALF(APAP-ALF).APAP-ALF occurs in three phases:metabolism,injury and recovery/regeneration.Before liver regeneration,emerging evidence shows that necrotic areas must be restricted/resolved,involving immune cells such as monocyte-derived macrophages(MoMFs)and migratory hepatocytes(figure 1A).Most patients with APAP-ALF in clinical settings have already progressed beyond the metabolic and injury phases,so enhancing the resolution of necrotic lesions as well as liver recovery and regeneration would be the most effective strategy to save their lives.展开更多
The alates of the green peach aphid, Myzus persicae, were daily trapped from the air from late October through early January and carried to laboratory for determination of fungal infection by individually rearing them...The alates of the green peach aphid, Myzus persicae, were daily trapped from the air from late October through early January and carried to laboratory for determination of fungal infection by individually rearing them for 7 d on detached cabbage leaves in Petri dishes. Among 760 alates trapped, 266 (35%) were found carrying various fungal pathogens, 87.3% of them died due to mycosis during the first 3-day period of rearing and the rest died in the following two days. Most of the deaths of the alates were attributed to entomophthoralean fungi, taking 94.4%, and the rest were the hyphomycetous fungus Beauveria bassiana. Among the Entomophthorales-killed alates, P. neoaphidis took a proportion of 66.1%, Z. anhuiensis 22.6%, E. planchoniana 9.7%, and N. fresenii 1.6%, respectively. Two alates were found suffering from cross infection of two fungal species, i.e. P. neoaphidis with Z. anhuiensis and N. fresenii, respectively. The results represent the first report on transmission of aphid-pathogenic fungi展开更多
Migratory birds are considered natural reservoirs of avian influenza A viruses(AIVs).To further our viral ecology knowledge and understand the subsequent risk posed by wild birds,we conducted a 4-year surveillance stu...Migratory birds are considered natural reservoirs of avian influenza A viruses(AIVs).To further our viral ecology knowledge and understand the subsequent risk posed by wild birds,we conducted a 4-year surveillance study of AIVs in the bird wintering wetlands of the Yangtze River,China.We collected over8000 samples and isolated 122 AIV strains.Analyses were then carried out with 108 novel sequenced genomes and data were deposited in GISAID and other public databases.The results showed that the Yangtze River wintering wetlands functioned as a mixing ground,where various subtypes of AIVs were detected harboring a high diversity of nucleotide sequences;moreover,a portion of AIV gene segments were persistent inter-seasonally.Phylogenetic incongruence presented complex reassortment events and distinct patterns among various subtypes.In addition,we observed that viral gene segments in wintering wetlands were closely related to known North American isolates,indicating that intercontinental gene flow occurred.Notably,highly pathogenic H5 and low pathogenic H9 viruses,which usually circulate in poultry,were found to have crossed the poultry/wild bird interface,with the viruses introduced to wintering birds.Overall,this study represented the largest AIV surveillance effort of wild birds within the Yangtze River wintering wetlands.Surveillance data highlighted the important role of wintering wild birds in the ecology of AIVs and may enable future early warnings of novel AIV emergence.展开更多
The Decision Support System (DSS) used by the Australian Plague Locust Commission for management of several important migratory insect pests in Australia is described. The DSS is based on a Geographic Information Sys...The Decision Support System (DSS) used by the Australian Plague Locust Commission for management of several important migratory insect pests in Australia is described. The DSS is based on a Geographic Information System that integrates data on weather and habitat condition with the migration, development and distribution of the pest to prepare forecasts and aid decisions for control. The GIS is module based with the number and nature of the modules easily modified depending on the detail of data required to manage the pest concerned.展开更多
In this paper,a new delayed fractional-order model including susceptible migratory birds,infected migratory birds and predators is proposed to discuss the spread of diseases among migratory birds.Fear of predators is ...In this paper,a new delayed fractional-order model including susceptible migratory birds,infected migratory birds and predators is proposed to discuss the spread of diseases among migratory birds.Fear of predators is considered in the model,as fear can reduce the reproduction rate and disease transmission rate among prey.First,some basic mathematical results of the proposed model are discussed.Then,time delay is regarded as a bifurcation parameter,and the delay-induced bifurcation conditions for such an uncontrolled system are established.A novel periodic pulse feedback controller is proposed to suppress the bifurcation phenomenon.It is found that the control scheme can successfully suppress the bifurcation behavior of the system,and the pulse width can be arbitrarily selected on the premise of ensuring the control effect.Compared with the traditional time-delay feedback controller,the control scheme proposed in this paper has more advantages in practical application,which not only embodies the advantages of low control cost and easy operation but also caters to the periodic changes of the environment.The proposed control scheme,in particular,remains effective even after the system has been disrupted by a constant.Numerical simulation verifies the correctness of the theoretical results.展开更多
文摘Asymmetric allylic C—H functionalization is a valuable and challenging research area. Different from the conventional direct allylic C—H cleavage strategy, transition metal-catalyzed migratory allylic substitution of remote dienes has emerged as a new route to achieve allylic C—H functionalization enantioselectively. This review provides a detailed summary of the development and advance of this strategy, introduces the related mechanistic processes, and discusses the area based on the types of catalysts and products.
基金supported by the Joint Chinese Academy of Sciences(CAS)-Max Planck Society(MPG)Research Project(HZXM20225001MI)the China Biodiversity Observation Networks(Sino BON)+1 种基金the Ministry of the Environment of Japan(ME20080401,ME20090401)the US Geological Survey(Grant No.07WRAG0003,G09AC00046).
文摘Bergmann's rule predicts that the larger of two homeotherm species differing only in size would occur at higher latitudes, or in cooler climates than the smaller, because of relative thermoregulatory costs in relation to body mass/surface area ratio. Individual tracking data from two congeneric long-distance migratory northern nesting swan species, Tundra Cygnus columbianus (TS, n = 99) and Whooper Swans C. cygnus (WS, 61–71% larger mass than TS, n = 47) were used to determine their summering and wintering latitudes along similar migration routes and common staging areas along the same flyway. We hypothesised that throughout Arctic and Boreal breeding areas (10℃ in July), summer ambient temperatures mainly exceed the Lower Critical Temperatures (LCT, c. 1℃) for both swan species, so the duration of the snow-free summer period will favour smaller body size at highest latitudes, since this constrains the time available to lay, incubate eggs and raise cygnets to fledging. We hypothesised that in contrast, in winter, both species occur in temperatures near to freezing (−3℃ in January), below their respective LCT, so differential thermoregulation demands would constrain TS to winter south of WS. Tracking of individuals showed for the first time that while smaller TS summered significantly north of WS, WS wintered significantly north of TS, with limited overlap in both seasons. We conclude that differences in relative summer distribution of these two closely related migratory herbivores are not to do with latitude per se but are constrained by the time both species require to raise their young to fledging during the short northern summer, when thermoregulation costs are unlikely limiting. In winter, both swan species occur within a climate envelop at or below their respective LCT and smaller TS occurred consistently south of the range of the tracked WS, as predicted by Bergmann's rule.
基金financial support from the National Natural Science Foundation of China(Nos.22271024,21632005)Changzhou University.
文摘Double bonds of internal olefins can be efficiently migrated to the terminal carbons and regioselectively hydroesterified with formates in the presence of Pd(OAc)_(2) and 1,2-DTBPMB under mild reaction conditions,providing a wide variety of corresponding linear carboxylic esters bearing various functional groups in good yields and>20:1 linear/branch ratios.The reaction is optionally simple and does not need to use CO gas and acid co-catalysts.
基金supported by the National Basic Research Program of China(2013CB430404)National Natural Science Foundation of China(31071939 and 31572280)+3 种基金the State Scholarship Fund of China(201206100060)supported by a Project Grant(621-2010-5584)from the Swedish Research Councila Linnaeus grant to the Centre for Animal Movement Research(CAn Move)from the Swedish Research Council(349-2007-8690)Lund University
文摘Background: The motivation of birds to proceed with migration is associated with both endogenous and exogenous factors. According to their migratory situation and to the characteristics of stopover sites, birds might exhibit migratory motivation differently among sites. Although migratory motivation of migrating birds has been well studied in many species, the investigation of the same species in different migratory situations and at different stopover sites is still limited. We predicted that birds at different stopover sites could differ in migratory disposition, including expression of migratory restlessness and responses to environmental cues.Methods: Here we compared migration motivation and orientation of Great Knots(Calidris tenuirostris) at two stopo ver sites, Chongming Dongtan in the south Yellow Sea, which is a temporary rest site, and Yalujiang Estuary Wetland in the north Yellow Sea, which is a critical refuelling site, during northward migration. Modified Emlen funnels, with thermal paper inside to record scratches of the birds, were used to detect activity(intensity and direction) of birds. Environmental conditions, including wind direction and speed, cloud cover, tide condition, times of the day(before and after sunset) were recorded during experiments. Generalized linear models were used to detect the effects of endogenous and exogenous factors on the migratory motivation of the birds.Results: In the south Yellow Sea, the migratory activity intensity of Great Knots was positively related to wind assistance. In the north Yellow Sea, where birds exhibited higher intensity of migratory activity than in the south, the intensity increased and the motivation to initiate migration grew stronger as the season advanced. The Great Knots exhibited wind-related orientation behaviour in the funnels at both sites.Conclusions: The results suggest that the intensity of migratory motivation differed between the two sites. Departure decisions of Great Knots appear to be affected mainly by external factors at the temporary rest site in the south Yellow Sea but possibly by endogenous factors at the final pre-breeding refuelling site in the north Yellow Sea.
基金financial support of the Asia–Pacific Network for Global Change Research project (reference number: ARCP2011-15NMYZhen)Technical Support Program of the Ministry of Science and Technology of China (No. 2013BAC03B04)the Key Project for the Strategic Science Plan of the Institute of Geographic Sciences and Natural Resources Research of the Chinese Academy of Sciences (No. 2012ZD007)
文摘Increasing human activities have contributed to global climate change, and thus resulted in a downward trend in the number of species and population sizes of migratory birds. This trend is closely related to a reduction in habitat size and lower habitat quality. The Poyang Lake wetland in China constitutes one of Asia's largest overwintering habitats for migratory birds. Over the past 10 years, restoration projects have improved the habitat ecology of these wetlands. In this study, we assessed the changes in habitat quality for overwintering migratory birds from 2000 to 2012 near two villages in the Poyang Lake wetland using the In VEST model. Average habitat quality for migratory birds has been improved by 18.8% and47.7%. Differences in the degrees of habitat improvement can be attributed to differences in the change of habitat size and in the impact of threat sources that resulted from the combined effects of restoration and human activities in these two villages.
基金supported by grants from the National Natural Science Foundation of China (31311120063,81470096,31570026,31471253)the Ministry of Education and Science of the Russian Federation (Chinese-Russian project:RFMEFI61315X0045)+3 种基金the intramural special grant for influenza virus research from the Chinese Academy of Sciences (KJZD-EW-L09)the IDRCAPEIR program (106915-001)Special Project of Ministry of Science and Technology (2013FY113500)supported by the “Taishan Scholar” project of Shandong Province
文摘A novel Clade 2.3.2.1c H5N1 reassortant virus caused several outbreaks in wild birds in some regions of China from late 2014 to 2015.Based on the genetic and phylogenetic analyses,the viruses possess a stable gene constellation with a Clade 2.3.2.1c HA,a H9N2-derived PB2 gene and the other six genes of Asian H5N1-origin.The Clade 2.3.2.1c H5N1 reassortants displayed a high genetic relationship to a human H5N1 strain(A/Alberta/01/2014).Further analysis showed that similar viruses have been circulating in wild birds in China,Russia,Dubai(Western Asia),Bulgaria and Romania(Europe),as well as domestic poultry in some regions of Africa.The affected areas include the Central Asian,East Asian-Australasian,West Asian-East African,and Black Sea/Mediterranean flyways.These results show that the novel Clade 2.3.2.1c reassortant viruses are circulating worldwide and may have gained a selective advantage in migratory birds,thus posing a serious threat to wild birds and potentially humans.
基金Supported by National Programs for Science and Technology Development(2011BAD16B01)Hunan Provincial Programs for Science and Technology Development(62020908011)~~
文摘In this study, the Bt-transgenic and non-transgenic rice were fed to three generations of oriental migratory Iocust, respectiveIy under Iaboratory conditions so as to investigate the effects of Bt-transgenic rice on coId resistance of oriental migratory Iocust. The supercooIing point and freezing point of oriental migratory Iocust was de-termined using supercooIing point meter. The resuIts showed that the supercooIing points of fourth instar Iarvae, fifth instar Iarvae, male aduIts and female aduIts, which were al fed with Bt-transgenic rice, were -5.89, -7.59, -6.64 and -6.79, respectiveIy. There were no significant differences between treatment and controI groups.
基金supported by the National Institutes of Health[U01-NS094340(Cullen),F31-NS090746(Katiyar)&F32-NS103253(O’Donnell)]University of Pennsylvania[Center for Undergraduate Research&Fellowships(Panzer)]+2 种基金Michael J.Fox Foundation[Therapeutic Pipeline Program#9998(Cullen)]Department of Veterans Affairs[RR&D Merit Review I01-RX001097(Cullen)&BLR&D Merit Review I01-BX003748(Cullen)]the U.S.Army Medical Research and Materiel Command[W81XWH-16-1-0796(Cullen)]
文摘New neurons are integrated into the circuitry of the olfactory bulb throughout the lifespan in the mamma- lian brain--including in humans. These new neurons are born in the subventricular zone and subsequently mature as they are guided over long distances via the rostral migratory stream through mechanisms we are only just beginning to understand. Regeneration after brain injury is very limited, and although some neuroblasts from the rostral migratory stream will leave the path and migrate toward cortical lesion sites, this neuronal replacement is generally not sustained and therefore does not provide enough new neurons to alleviate functional deficits. Using newly discovered microtissue engineering techniques, we have built the first self-contained, implantable constructs that mimic the architecture and function of the rostral migratory stream. This engineered microtissue emulates the dense cord-like bundles of astrocytic somata and processes that are the hallmark anatomical feature of the glial tube. As such, our living microtissue-en- gineered rostral migratory stream can serve as an in vitro test bed for unlocking the secrets of neuroblast migration and maturation, and may potentially serve as a living transplantable construct derived from a patient＇s own cells that can redirect their own neuroblasts into lesion sites for sustained neuronal replace- ment following brain injury or neurodegenerative disease. In this paper, we summarize the development of fabrication methods for this microtissue-engineered rostral migratory stream and provide proof-of-princi- ple evidence that it promotes and directs migration of immature neurons.
文摘One possible hypothesis for the function of post-fledging dispersal is to locate a suitable future breeding area.This post-fledging period may be particularly important in migratory species because they have a limited period to gather information prior to autumn migration,and in protandrous species,males must quickly acquire a territory after returning from spring migration to maximize their fitness.Here we use color-ring resightings to investigate how the post-fledging dispersal movements of the Cyprus wheatear Oenanthe cypriaca,a small migratory passerine,relate to their first breeding territory the following year when they return from migration.We found that males established first breeding territories that were significantly closer to their post-fledging location than to their natal sites or to post-fledging locations of other conspecifics,but these patterns were not apparent in females.Our findings suggest that familiarity with potential breeding sites may be important for juveniles of migratory species,particularly for the sex that acquires and advertises breeding territories.Exploratory dispersal prior to a migrant’s first autumn migration may contribute toward its breeding success the following year,further highlighting the importance of early seasonal breeding on fitness and population dynamics more generally.
基金The National Natural Science Foundation of China under contract Nos 41930534 and 41876177
文摘Japanese Spanish mackerel,Scomberomorus niphonius,is a commercially important,highly migratory species that is widely distributed throughout the northwestern Pacific region.However,its life history and migratory patterns are only partially understood.This study used otolith chemistry to investigate the migratory pattern of S.niphonius in the southern Yellow Sea,an important fishing ground.Transverse sections of otoliths from 15 age-1 spawning or spent individuals,comprising up to one complete migration cycle,were analyzed from the core to the margin by using laser ablation inductively coupled plasma mass spectrometry.The ratios of the element to Ca were integrated with microstructural analysis to produce age-related elemental profiles.Combining multielemental analysis of otolith composition with multivariate analytical models,we quantified structural changes in otolith chemistry profiles.Results revealed there were diverse changing patterns of otolith chemistry profiles for detected elements and the elements of Na,Mg,Sr and Ba were important for the chronological signal.Five clusters were identified through chronological clustering,representing the five life stages from the early stage to the spawning stage.Variation of Ba:Ca ratio was most informative,showing a step-decreasing pattern in the first four stages and a rebound in the spawning stage.These results support the hypothesized migratory pattern of S.niphonius:hatching and spending their early life in the coastal sandy ridges system of the southern Yellow Sea,migrating northeastward and offshore for feeding during juvenile stage,aggregating in early October and migrating outward to the Jeju Island for wintering,and returning to the coastal waters for spawning.This study demonstrated the value of life-history related otolith chemistry profiles combined with multivariate analytical models was a means to verify the migration patterns of S.niphonius at regional scales with potential application in fisheries assessment and management.
基金Supported by Special Item of the Climate Change,China Meteorological Administration(CCSF201205)Key Item of the Hunan Meteorological Bureau(201202)
文摘[Objective] The research aimed to study influences of the weather and climate on wintering migratory bird in Dongting Lake. [Method] Bird analysis data provided by East Dongting Lake National Nature Reserve and wintering migratory bird monitoring data in big and small west lakes in recent 5 years were used. By combing water level data and various meteorological factors in Chenglingji, wintering migratory bird in Dongting Lake was analyzed. [Result] Abnormal precipitation led to drought or flood in Dongting Lake, causing significant adverse effect on the birds. Abnormal climate was important reason for that wintering migratory bird greatly reduced, such as high temperature and later going south of the strong cold air. Extreme weather and climate events led that some birds in Dongting Lake significantly reduced. Meteorological element had certain influence to bird survey. We should select a reasonable investigation time based on weather and climate. In Birding Festival, weather had little effect on bird species observation. In the migratory season of bird, we could see many birds in fine cold weather after a strong cold air, which suitable for observing bird. When it was low temperature or less rain in autumn, and was high temperature or more rain and sunshine in early winter, it was suitable for migratory birds wintering in Dongting Lake. Ardea cinerea, Anser fabalis and Anser erythropus were more in sunny days while Phalacrocorax carbo was more in rainy weather. Grus grus was more in heavy wind weather while Recurvirostra avosetta was more in small wind weather. [Conclusion] The research provided scientific basis for studying migratory bird in east Dongting Lake.
基金University Provincial Scientific Research Project,Key Humanities and Social Sciences Research Project (2011sk458zd) University-level Scientific Research Project in Chuzhou University(2010sk0138) the First Federation of Social Sciences Project in Chuzhou City (B2011020)
文摘I divide the rural households into three types:the rural households unwilling to move;the floating rural households;the migratory rural households.Through questionnaire survey of the married housewives in Anhui Province and Zhejiang Province,I conduct comparative analysis of income and expenditure,change in the status of family members,the couple's housework time,the wives' will to settle in the city and attitude towards life,related to these three types of rural households.Results show that promoting wives' educational level and monthly family income will significantly make the wives in households unwilling to move,have stronger desire to make their children settle in the city;the housework time of the wives in the floating households is 3.4 times that of their husbands,the monthly income of the husbands in the floating households is significantly lower than that of the husbands in the migratory households,with heavy family burden assessed by themselves;the age of the wives in the migratory households is the smallest,and the educational level and income of them are the highest,but the monthly expenditure has not yet significantly expanded,and at the same time,the migratory households have the weakest desire to settle in the city.The recommendations concerning these three types of rural households are put forward as follows:promoting the skills of the members in the households unwilling to move,in agricultural cultivation,development of agricultural products and circulation of agricultural products;paying close attention to the floating rural households;promoting the government,enterprise,households to work together to stabilize the migratory households.
文摘What has really happened in Europe since 2014?Why in 2018 are so many migrants still making their way towards Europe?For the first time since the Second World War,an important number of individuals have entered into European soil.The idea for this article goes back to October 2015 when the prefet from the town where I live went in search of asylum seekers.This is what sparked off my inquiry amongst about 50 exiles housed in the annex of the Montmorency(95)hospital in July 2015.But against popular belief,migrants are not accepted fairly into countries,and the geographical distribution of Syrians in Turkey,Lebanon,Jordan,and Europe is contrary to what Kant had defended as a“right to visit”.Although the majority of researchers suggest welcoming migrants,it is necessary to reconsider some methodological and epistemological aspects and get away from some wrongly perceived concepts which dated prior to the year 2000.Yet,the Arab Spring has showed that we are dealing with unfinished post-colonialism,something that we will soon come back to in another article where we will propose another solution.
基金approved by the Animal Ethics Committee ofthe Institute of Microbiology,Chinese Academy of Sciences(Approval Number:APIMCAS2018034 and APIMCAS2021112).
文摘Impact statementThis study identifies avian tuberculosis as a potential cause of mass mortality in wild migratory birds in Inner Mongolia,China.Combining meta-transcriptomic sequencing and histopathological analysis,it reveals one of the rare instances oftuberculosis-associated outbreaks in avian populations.Thesefindings underscore the importance of surveillance on wildlifediseases to mitigate the risk of interspecies transmission of the disease associated pathogens and their broader implicationsfor biodiversity and public health.
基金supported in part by the National Institute of Health(NIH)funds R37 AA020518,R21 AA030617,R01AA031230(WXD),and R01DK134737(HMN).
文摘Acute liver failure(ALF)is the onset of severe liver injury without pre-existing chronic liver diseases.12 The most common type of drug-induced ALF is caused by acetaminophen(APAP)overdose,which accounts for 45.7%of ALF cases in the US.2 In severe cases of ALF,liver transplantation remains the only curative option.12 Nonetheless,there is currently a shortage of liver donor organs available to meet the demands for liver transplantation needed to save the lives of patients with ALF.Due to the increasing prevalence of metabolic dysfunction-associated steatotic liver disease and metabolic and alcohol-associated liver disease,34 many steatotic livers are discarded,further exacerbating the burden of liver shortages.Therefore,it is crucial to find therapeutic approaches that can potentially alleviate APAP-induced ALF(APAP-ALF).APAP-ALF occurs in three phases:metabolism,injury and recovery/regeneration.Before liver regeneration,emerging evidence shows that necrotic areas must be restricted/resolved,involving immune cells such as monocyte-derived macrophages(MoMFs)and migratory hepatocytes(figure 1A).Most patients with APAP-ALF in clinical settings have already progressed beyond the metabolic and injury phases,so enhancing the resolution of necrotic lesions as well as liver recovery and regeneration would be the most effective strategy to save their lives.
基金This work was partially supported by the "Cheung Kong Scholars Programme', Ministry of Education, P. R. Chinathe National Natural Science Foundation of China (Grant Nos. 30070514 and 39870513).
文摘The alates of the green peach aphid, Myzus persicae, were daily trapped from the air from late October through early January and carried to laboratory for determination of fungal infection by individually rearing them for 7 d on detached cabbage leaves in Petri dishes. Among 760 alates trapped, 266 (35%) were found carrying various fungal pathogens, 87.3% of them died due to mycosis during the first 3-day period of rearing and the rest died in the following two days. Most of the deaths of the alates were attributed to entomophthoralean fungi, taking 94.4%, and the rest were the hyphomycetous fungus Beauveria bassiana. Among the Entomophthorales-killed alates, P. neoaphidis took a proportion of 66.1%, Z. anhuiensis 22.6%, E. planchoniana 9.7%, and N. fresenii 1.6%, respectively. Two alates were found suffering from cross infection of two fungal species, i.e. P. neoaphidis with Z. anhuiensis and N. fresenii, respectively. The results represent the first report on transmission of aphid-pathogenic fungi
基金supported by the National Natural Science Foundation of China(81961138013,31570026,31970174,31970548,and 32061123001)the National Mega Project on Major Infectious Disease Prevention(2017ZX10103005-005)+1 种基金the Special Project of Ministry of Science and Technology(2013FY113500)the Russian Foundation for Basic Research—National Natural Science Foundation of China Collaboration Fund(19-54-55004)。
文摘Migratory birds are considered natural reservoirs of avian influenza A viruses(AIVs).To further our viral ecology knowledge and understand the subsequent risk posed by wild birds,we conducted a 4-year surveillance study of AIVs in the bird wintering wetlands of the Yangtze River,China.We collected over8000 samples and isolated 122 AIV strains.Analyses were then carried out with 108 novel sequenced genomes and data were deposited in GISAID and other public databases.The results showed that the Yangtze River wintering wetlands functioned as a mixing ground,where various subtypes of AIVs were detected harboring a high diversity of nucleotide sequences;moreover,a portion of AIV gene segments were persistent inter-seasonally.Phylogenetic incongruence presented complex reassortment events and distinct patterns among various subtypes.In addition,we observed that viral gene segments in wintering wetlands were closely related to known North American isolates,indicating that intercontinental gene flow occurred.Notably,highly pathogenic H5 and low pathogenic H9 viruses,which usually circulate in poultry,were found to have crossed the poultry/wild bird interface,with the viruses introduced to wintering birds.Overall,this study represented the largest AIV surveillance effort of wild birds within the Yangtze River wintering wetlands.Surveillance data highlighted the important role of wintering wild birds in the ecology of AIVs and may enable future early warnings of novel AIV emergence.
文摘The Decision Support System (DSS) used by the Australian Plague Locust Commission for management of several important migratory insect pests in Australia is described. The DSS is based on a Geographic Information System that integrates data on weather and habitat condition with the migration, development and distribution of the pest to prepare forecasts and aid decisions for control. The GIS is module based with the number and nature of the modules easily modified depending on the detail of data required to manage the pest concerned.
基金supported by Liaoning Provincial Department of Education Scientific Research Fund Project(lnjc202018).
文摘In this paper,a new delayed fractional-order model including susceptible migratory birds,infected migratory birds and predators is proposed to discuss the spread of diseases among migratory birds.Fear of predators is considered in the model,as fear can reduce the reproduction rate and disease transmission rate among prey.First,some basic mathematical results of the proposed model are discussed.Then,time delay is regarded as a bifurcation parameter,and the delay-induced bifurcation conditions for such an uncontrolled system are established.A novel periodic pulse feedback controller is proposed to suppress the bifurcation phenomenon.It is found that the control scheme can successfully suppress the bifurcation behavior of the system,and the pulse width can be arbitrarily selected on the premise of ensuring the control effect.Compared with the traditional time-delay feedback controller,the control scheme proposed in this paper has more advantages in practical application,which not only embodies the advantages of low control cost and easy operation but also caters to the periodic changes of the environment.The proposed control scheme,in particular,remains effective even after the system has been disrupted by a constant.Numerical simulation verifies the correctness of the theoretical results.
