The effects of semiochemicals extracted from 63 species of plants, on peach aphid (Myzus per-sicae) and mustard aphid (Lipaphis erysimi), were studied in laboratory. The deterrent rate, reproduction deterrent index an...The effects of semiochemicals extracted from 63 species of plants, on peach aphid (Myzus per-sicae) and mustard aphid (Lipaphis erysimi), were studied in laboratory. The deterrent rate, reproduction deterrent index and the interferential index of population control (IIPC) was used to evaluate the efficiency of semiochemicals on population control of the two target aphids. The results showed that the extracts of 34 species of common plants have noticeable effect on both aphid populations, especially, Xanthium sibiricum Petr. Et Widd. and Syngonium podophyllum Schott. These plant extracts could be used to construct the plant pro-tectant to protect crops.展开更多
Dong ethnic people have rich indigenous knowledge in terms of their daily life and production, which plays an important role in the sustainable development of their village. This paper aims to understand traditional k...Dong ethnic people have rich indigenous knowledge in terms of their daily life and production, which plays an important role in the sustainable development of their village. This paper aims to understand traditional knowledge of Dong ethnic people in resource management and population control, including traditional resource management, traditional medicinal knowledge and village regulations in Zhanli Village in Southeast Guizhou Province. The research methods include key informant interview, group discussion, participant observation and secondary data collect- ing. The results show that Zhanli villagers try their best to utilize indigenous knowledge to manage the natural resources and keep the stable population to make themselves live in a sustainable way. Indigenous knowledge plays an important role in managing their limited natural resources and keeping the population stable under an excellent condition. Zhanli villagers employ indigenous knowledge to manage natural resources and use local herbs to control the population. Village regulation terms significantly influence villagers’ awareness in resource management and birth control. Women play the chief role in employing indigenous knowledge in weaving as well as medicinal knowledge in birth control, and these kinds of knowledge are passed down through the female line. However, the inheritance style of traditional knowledge is decreasing. Indig- enous knowledge plays an important role in the sustainable development of this village, which gives implications for development practices to involve indigenous knowledge to achieve sustainable development.展开更多
China as the world＇ s most populous country, the number of demographic change is an essential element of social development plan under consideration. This article combined with the background, based on the birth rate...China as the world＇ s most populous country, the number of demographic change is an essential element of social development plan under consideration. This article combined with the background, based on the birth rate, mortality indicators as well as the corresponding changes in the age structure, demographic trends predict the future based on the current form of the economy analysis the population of 60 years since the founding of New China .China＇ s population control based on the complexity of the future still need to take tight family planning policy, change the mechanism of population control, optimize population structure, improve population quality.展开更多
Mr.Jiang Zcmin,Gencral-Seerctary of the Cen-tral Committee of the Chincse Communist Party and.Chairman of the People's Republic of China,in a rC-ccnt spcech cm phasized that the family planning pro-gramme should b...Mr.Jiang Zcmin,Gencral-Seerctary of the Cen-tral Committee of the Chincse Communist Party and.Chairman of the People's Republic of China,in a rC-ccnt spcech cm phasized that the family planning pro-gramme should be strictly and effectively im plemented in 1994,a year of crucial importance for promoting re-form and opening and thc drive lowards.modernization.To makc continucd contributions to the sociocconomic development in the country,we must fulfil the plan for controlling population growth..The spcech was delivcred at the anua!National Fo-rum on Family Planning Work convened jointly by the Party's Central Committcc and the Statc Council.展开更多
[Objective] The paper was to clear biological characteristics and comprehensive prevention and treatment methods of Acantholyda piceacola Xiao et Zhou. [Method] Through captive observation and field survey,the current...[Objective] The paper was to clear biological characteristics and comprehensive prevention and treatment methods of Acantholyda piceacola Xiao et Zhou. [Method] Through captive observation and field survey,the current situation,life history and life habits of A. piceacola were investigated; the occurrence degree of A. piceacola in various regions and the relationship between soil depth and number distribution of A. piceacola were studied. Moreover,the contrast test of a variety of control measures was conducted. [Result] A. piceacola needed one year or more to complete a generation; there were significant differences in insect plant rate and extremely significant differences in population density among different plots. Trunk injection and foliar spraying conducted before the forth larval stage had good protection effects on needles of Picea mongolica; trunk injection with 14% imidacloprid · dichlorvos at egg stage received the best control effect,the loss rate of needles was the lowest of 8. 43%,so the method could be massively popularized in the future. [Conclusion]The results provide a reference for the control of A. piceacola.展开更多
Dear Editor,In January 2020,a widespread outbreak of coronavirus disease 2019(COVID-19)occurred after the beginning of the largest annual migration in China,which is known as the Spring Festival migration.Starting in ...Dear Editor,In January 2020,a widespread outbreak of coronavirus disease 2019(COVID-19)occurred after the beginning of the largest annual migration in China,which is known as the Spring Festival migration.Starting in January 20,2020,the Chinese government took a series of unprecedented measures to contain the spread of COVID-19.Because of the role of Wuhan as a central transportation hub.展开更多
The native range of Ctenosaura similis extends from southern Mexico through Panama. From an initial introduction of 3 animals in 1979, the species now numbers in the thousands on Gasparilla Island in southwest F...The native range of Ctenosaura similis extends from southern Mexico through Panama. From an initial introduction of 3 animals in 1979, the species now numbers in the thousands on Gasparilla Island in southwest Florida. In response to complaints of property damage from residents and threats to native species, local officials and the US Department of Agriculture Wildlife Services began a removal program in 2008. Through 2011, trappers removed 9467 ctenosaurs. The number removed declined from 32 iguanas/day in 2008 to 1.9 iguanas/day in 2011 despite no easing of the control effort. We necropsied 2757 ctenosaurs to document aspects of their natural history. Females outnumbered males overall, although the largest size class (>300 mm snout-vent length) included 32 males and just 2 females. Reproduction was seasonal. We found oviducal eggs in females from early Apr to early Jun, approximately 2 months later than C. similis in its native range. We trapped hatchlings from late Jul to early Oct coincident with the summer rainy season. Clutch size increased with female body size, with 62 being the largest clutch size recorded. In general, the biology of the invasive population on Gasparilla Island resembles native C. similis populations in Central America, except for the lack of large individuals. We suggest that shorter day length and colder temperatures create environmental conditions that are suboptimal for individual growth compared to those in the native range.展开更多
Crystal morphology is known to be of great importance to the end-use properties of crystal products, and to affect down-stream processing such as filtration and drying. However, it has been previously regarded as too ...Crystal morphology is known to be of great importance to the end-use properties of crystal products, and to affect down-stream processing such as filtration and drying. However, it has been previously regarded as too challenging to achieve automatic closed-loop control. Previous work has focused on controlling the crystal size distribution, where the size of a crystal is often defined as the diameter of a sphere that has the same volume as the crystal. This paper reviews the new advances in morphological population balance models for modelling and simulating the crystal shape distribution （CShD）, measuring and estimating crystal facet growth kinetics, and two- and three-dimensional imaging for on-line characterisation of the crystal morphology and CShD. A framework is presented that integrates the various components to achieve the ultimate objective of model-based closed-loop control of the CShD. The knowledge gaps and challenges that require further research are also identified.展开更多
文摘The effects of semiochemicals extracted from 63 species of plants, on peach aphid (Myzus per-sicae) and mustard aphid (Lipaphis erysimi), were studied in laboratory. The deterrent rate, reproduction deterrent index and the interferential index of population control (IIPC) was used to evaluate the efficiency of semiochemicals on population control of the two target aphids. The results showed that the extracts of 34 species of common plants have noticeable effect on both aphid populations, especially, Xanthium sibiricum Petr. Et Widd. and Syngonium podophyllum Schott. These plant extracts could be used to construct the plant pro-tectant to protect crops.
文摘Dong ethnic people have rich indigenous knowledge in terms of their daily life and production, which plays an important role in the sustainable development of their village. This paper aims to understand traditional knowledge of Dong ethnic people in resource management and population control, including traditional resource management, traditional medicinal knowledge and village regulations in Zhanli Village in Southeast Guizhou Province. The research methods include key informant interview, group discussion, participant observation and secondary data collect- ing. The results show that Zhanli villagers try their best to utilize indigenous knowledge to manage the natural resources and keep the stable population to make themselves live in a sustainable way. Indigenous knowledge plays an important role in managing their limited natural resources and keeping the population stable under an excellent condition. Zhanli villagers employ indigenous knowledge to manage natural resources and use local herbs to control the population. Village regulation terms significantly influence villagers’ awareness in resource management and birth control. Women play the chief role in employing indigenous knowledge in weaving as well as medicinal knowledge in birth control, and these kinds of knowledge are passed down through the female line. However, the inheritance style of traditional knowledge is decreasing. Indig- enous knowledge plays an important role in the sustainable development of this village, which gives implications for development practices to involve indigenous knowledge to achieve sustainable development.
文摘China as the world＇ s most populous country, the number of demographic change is an essential element of social development plan under consideration. This article combined with the background, based on the birth rate, mortality indicators as well as the corresponding changes in the age structure, demographic trends predict the future based on the current form of the economy analysis the population of 60 years since the founding of New China .China＇ s population control based on the complexity of the future still need to take tight family planning policy, change the mechanism of population control, optimize population structure, improve population quality.
文摘Mr.Jiang Zcmin,Gencral-Seerctary of the Cen-tral Committee of the Chincse Communist Party and.Chairman of the People's Republic of China,in a rC-ccnt spcech cm phasized that the family planning pro-gramme should be strictly and effectively im plemented in 1994,a year of crucial importance for promoting re-form and opening and thc drive lowards.modernization.To makc continucd contributions to the sociocconomic development in the country,we must fulfil the plan for controlling population growth..The spcech was delivcred at the anua!National Fo-rum on Family Planning Work convened jointly by the Party's Central Committcc and the Statc Council.
基金Supported by Special Fund for Forest Scientific Research in the Public Welfare(201504412)
文摘[Objective] The paper was to clear biological characteristics and comprehensive prevention and treatment methods of Acantholyda piceacola Xiao et Zhou. [Method] Through captive observation and field survey,the current situation,life history and life habits of A. piceacola were investigated; the occurrence degree of A. piceacola in various regions and the relationship between soil depth and number distribution of A. piceacola were studied. Moreover,the contrast test of a variety of control measures was conducted. [Result] A. piceacola needed one year or more to complete a generation; there were significant differences in insect plant rate and extremely significant differences in population density among different plots. Trunk injection and foliar spraying conducted before the forth larval stage had good protection effects on needles of Picea mongolica; trunk injection with 14% imidacloprid · dichlorvos at egg stage received the best control effect,the loss rate of needles was the lowest of 8. 43%,so the method could be massively popularized in the future. [Conclusion]The results provide a reference for the control of A. piceacola.
基金the Fundamental Research Funds for the Central Universities (YD9110004001 to JW, YD9110002002 to XY)Emergency Research Project of Novel Coronavirus Infection of Anhui Province (202004a07020002 to ZRL202004a07020004 to ZRL)。
文摘Dear Editor,In January 2020,a widespread outbreak of coronavirus disease 2019(COVID-19)occurred after the beginning of the largest annual migration in China,which is known as the Spring Festival migration.Starting in January 20,2020,the Chinese government took a series of unprecedented measures to contain the spread of COVID-19.Because of the role of Wuhan as a central transportation hub.
文摘The native range of Ctenosaura similis extends from southern Mexico through Panama. From an initial introduction of 3 animals in 1979, the species now numbers in the thousands on Gasparilla Island in southwest Florida. In response to complaints of property damage from residents and threats to native species, local officials and the US Department of Agriculture Wildlife Services began a removal program in 2008. Through 2011, trappers removed 9467 ctenosaurs. The number removed declined from 32 iguanas/day in 2008 to 1.9 iguanas/day in 2011 despite no easing of the control effort. We necropsied 2757 ctenosaurs to document aspects of their natural history. Females outnumbered males overall, although the largest size class (>300 mm snout-vent length) included 32 males and just 2 females. Reproduction was seasonal. We found oviducal eggs in females from early Apr to early Jun, approximately 2 months later than C. similis in its native range. We trapped hatchlings from late Jul to early Oct coincident with the summer rainy season. Clutch size increased with female body size, with 62 being the largest clutch size recorded. In general, the biology of the invasive population on Gasparilla Island resembles native C. similis populations in Central America, except for the lack of large individuals. We suggest that shorter day length and colder temperatures create environmental conditions that are suboptimal for individual growth compared to those in the native range.
基金Financial support from the following projects and organisa- tions are acknowledged： the China One Thousand Talent Scheme, the National Natural Science Foundation of China （NNSFC） under its Major Research Scheme of Meso-scale Mechanism and Control in Multi-phase Reaction Processes （project reference： 91434126）, the Natural Science Foundation of Guangdong Province （project reference： 2014A030313228）, the UK Engineering and Physical Sciences Research Council （EPSRC） for the projects of Shape （EP/C009541） and StereoVision （EP/E045707）, and the Technology Strategy Board （TSB） for the project of High Value Manufacturing CGM （TP/BD059E）.
文摘Crystal morphology is known to be of great importance to the end-use properties of crystal products, and to affect down-stream processing such as filtration and drying. However, it has been previously regarded as too challenging to achieve automatic closed-loop control. Previous work has focused on controlling the crystal size distribution, where the size of a crystal is often defined as the diameter of a sphere that has the same volume as the crystal. This paper reviews the new advances in morphological population balance models for modelling and simulating the crystal shape distribution （CShD）, measuring and estimating crystal facet growth kinetics, and two- and three-dimensional imaging for on-line characterisation of the crystal morphology and CShD. A framework is presented that integrates the various components to achieve the ultimate objective of model-based closed-loop control of the CShD. The knowledge gaps and challenges that require further research are also identified.
