A specimen of White-spectacled Warbler Seicercus affinis was collected in Diding Nature Reserve in Jingxi County, Southwest Guangxi province in December 2006. It is a new record of bird species in Guangxi. During our ...A specimen of White-spectacled Warbler Seicercus affinis was collected in Diding Nature Reserve in Jingxi County, Southwest Guangxi province in December 2006. It is a new record of bird species in Guangxi. During our field investigation in Diding Nature Reserve from January 2005 to May 2007, Seicercus affinis were observed frequently in the underbrush of the evergreen broad-leaved forest and the shrub around agricultural land at an altitude of 500-700m. There are two subspecies of Seicercus affinis recorded in the world, but only one in China. Through a careful examination, this specimen was identified as Seicercus affinis intermedius. The distribution ofSeicercus affinis in China will be discussed in this paper. The specimen was kept at the College of Animal Sciences and Technology, Guangxi University.展开更多
In this study, the relationship of the growth of invasion fish with water eutrophication processes was explored in Yangtze estuary, China. High water ammonia nitrogen concentration produced high effects on the growth ...In this study, the relationship of the growth of invasion fish with water eutrophication processes was explored in Yangtze estuary, China. High water ammonia nitrogen concentration produced high effects on the growth and survival of mosquitofish Gambusia affinis. When the ammonia nitrogen was higher than 51.75 mg/l, the fish death rate obviously increased with days, and at the 4th day fish presented the highest mortality, while 23.72 mg/l ammonia nitrogen conditions have been able to ensure fish survival for two days in experiment treatment. Therefore, ammonia nitrogen of Grade V polluted water (national water quality criteria) is just 3 mg/l, and the water can be enough to support fish normal survival. Our results suggest mosquitofish was a suitable pioneer species for restoring polluted water ecology and purify water.展开更多
llex paraguariensis St. Hilaire （Aquifoliaceae） is processed industrially to produce the commercial product ＂yerba mate＂ which is used as a tea-like beverage. It is one of the most commercialized plants of South A...llex paraguariensis St. Hilaire （Aquifoliaceae） is processed industrially to produce the commercial product ＂yerba mate＂ which is used as a tea-like beverage. It is one of the most commercialized plants of South America. It is exported to the US, Europe and Asia as vegetal drug or extracts used in complementary and alternative medicine and in formulations for functional foods due to its properties as a CNS stimulant, diuretic, weight reducing, antioxidant and antihypercholesterolemic, among others, llex affinis grows in the same habitat and is used as substitute or adulterant ofI. paraguariensis. This species was never investigated before. The objective of this work was to assess the phytochemical composition and to determine the pharmacological activity, according with the major compounds present in it. The results showed small quantities of caffeine and theobromine, but a considerable amount of polyphenols, especially chlorogenic acid and isochlorogenic acid. I. affinis extracts presented scavenging activity on free radical DPPH in a concentration-dependent manner. Antiproliferative action on lymphoma cell line exerting both cytostatic and cytotoxic activities was also demonstrated.展开更多
Bat coronavirus(CoV)RaTG13 shares the highest genome sequence identity with severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)among all known coronaviruses,and also uses human angiotensin converting enzyme 2(...Bat coronavirus(CoV)RaTG13 shares the highest genome sequence identity with severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)among all known coronaviruses,and also uses human angiotensin converting enzyme 2(hACE2)for virus entry.Thus,SARS-CoV-2 is thought to have originated from bat.However,whether SARS-CoV-2 emerged from bats directly or through an intermediate host remains elusive.Here,we found that Rhinolophus affinis bat ACE2(Ra ACE2)is an entry receptor for both SARSCoV-2 and Ra TG13,although the binding of Ra ACE2 to the receptor-binding domain(RBD)of SARSCoV-2 is markedly weaker than that of h ACE2.We further evaluated the receptor activities of ACE2 s from additional 16 diverse animal species for Ra TG13,SARS-CoV,and SARS-CoV-2 in terms of S protein binding,membrane fusion,and pseudovirus entry.We found that the Ra TG13 spike(S)protein is significantly less fusogenic than SARS-CoV and SARS-CoV-2,and seven out of sixteen different ACE2 s function as entry receptors for all three viruses,indicating that all three viruses might have broad host rages.Of note,Ra TG13 S pseudovirions can use mouse,but not pangolin ACE2,for virus entry,whereas SARS-CoV-2 S pseudovirions can use pangolin,but not mouse,ACE2 enter cells efficiently.Mutagenesis analysis revealed that residues 484 and 498 in Ra TG13 and SARS-CoV-2 S proteins play critical roles in recognition of mouse and human ACE2 s.Finally,two polymorphous Rhinolophous sinicus bat ACE2 s showed different susceptibilities to virus entry by Ra TG13 and SARS-CoV-2 S pseudovirions,suggesting possible coevolution.Our results offer better understanding of the mechanism of coronavirus entry,host range,and virushost coevolution.展开更多
In order to maintain soil fertility of Neosinocalamus affinis plantations,fertilizers of N,P,and K were applied.The anatomical and physical-mechanical properties of N.affinis bamboo wood from different fertilization t...In order to maintain soil fertility of Neosinocalamus affinis plantations,fertilizers of N,P,and K were applied.The anatomical and physical-mechanical properties of N.affinis bamboo wood from different fertilization treatments were measured.The aim of this study was to elucidate the effect of fertilization practice on the properties of N.affinis bamboo wood.The results revealed that the fertilization of P and K resulted in a slight reduction in fiber length.The application of P,K,and low level(0.3 kg/clump)of N fertilizers had no significant effect on the fiber morphology,while high level(0.9 kg/clump)of N fertilizer contributed to short fibers.The specific gravity was significantly decreased by fertilization,while the volume shrinkage was increased.Since the effect of various fertilization treatments had different influence patterns on the properties of N.affinis,specific evaluations on the quality of the fertilized bamboo wood should be performed prior to its utilization.展开更多
Diflubenzuron (DFB, trade name dimilin 25 WP) is a chitin synthesis inhibitor widely used against forest insect pests in Algeria. Prior to implementation of these products as chemical agents for mosquito control, know...Diflubenzuron (DFB, trade name dimilin 25 WP) is a chitin synthesis inhibitor widely used against forest insect pests in Algeria. Prior to implementation of these products as chemical agents for mosquito control, knowledge on their potential effects on non-target organisms and its behaviour in water are needed. Therefore, the present study was focused on DFB and aimed to use an HPLC procedure developed previously in order to obtain information on its degradation in freshwater and its bioconcentration in adult females of the fish Gambusia affinis (Cyprinodondiformes, Poeciliidae), which is one of the best candidates for biological control programs against mosquitoes. The adult females were exposed to dimilin (initial concentration 312 ng a.i./ml) for 28 days and residues analysis determined at different exposure times (0, 7, 14, 21 and 28 days). The concentration of DFB in freshwater decreased with exposure time while the amount of residues detected at the surface of the fish body increased progressively to reach a maximum at day 14 (162.7 ± 14.0 ng/fish) and declined thereafter during the exposure period. In addition, DFB incorporation into body increased with decreasing DFB concentration in water at each exposure time. The following average distribution was noted at the end of experiment (28 days): about 33% of the applied concentration was detected on the surface of fish body and was recovered by simple rinsing, and about 67% was found inside the fish body. A degradation in water and surface of fish occurred starting day 14 during the experimental period. Thus, about 40% of the initial concentration was degraded in freshwater after 28 days. The results are discussed to develop a better understanding of the degradation of dimilin in water and their potential effect on non-target organisms for its application for controlling mosquito.展开更多
文摘A specimen of White-spectacled Warbler Seicercus affinis was collected in Diding Nature Reserve in Jingxi County, Southwest Guangxi province in December 2006. It is a new record of bird species in Guangxi. During our field investigation in Diding Nature Reserve from January 2005 to May 2007, Seicercus affinis were observed frequently in the underbrush of the evergreen broad-leaved forest and the shrub around agricultural land at an altitude of 500-700m. There are two subspecies of Seicercus affinis recorded in the world, but only one in China. Through a careful examination, this specimen was identified as Seicercus affinis intermedius. The distribution ofSeicercus affinis in China will be discussed in this paper. The specimen was kept at the College of Animal Sciences and Technology, Guangxi University.
文摘In this study, the relationship of the growth of invasion fish with water eutrophication processes was explored in Yangtze estuary, China. High water ammonia nitrogen concentration produced high effects on the growth and survival of mosquitofish Gambusia affinis. When the ammonia nitrogen was higher than 51.75 mg/l, the fish death rate obviously increased with days, and at the 4th day fish presented the highest mortality, while 23.72 mg/l ammonia nitrogen conditions have been able to ensure fish survival for two days in experiment treatment. Therefore, ammonia nitrogen of Grade V polluted water (national water quality criteria) is just 3 mg/l, and the water can be enough to support fish normal survival. Our results suggest mosquitofish was a suitable pioneer species for restoring polluted water ecology and purify water.
文摘llex paraguariensis St. Hilaire （Aquifoliaceae） is processed industrially to produce the commercial product ＂yerba mate＂ which is used as a tea-like beverage. It is one of the most commercialized plants of South America. It is exported to the US, Europe and Asia as vegetal drug or extracts used in complementary and alternative medicine and in formulations for functional foods due to its properties as a CNS stimulant, diuretic, weight reducing, antioxidant and antihypercholesterolemic, among others, llex affinis grows in the same habitat and is used as substitute or adulterant ofI. paraguariensis. This species was never investigated before. The objective of this work was to assess the phytochemical composition and to determine the pharmacological activity, according with the major compounds present in it. The results showed small quantities of caffeine and theobromine, but a considerable amount of polyphenols, especially chlorogenic acid and isochlorogenic acid. I. affinis extracts presented scavenging activity on free radical DPPH in a concentration-dependent manner. Antiproliferative action on lymphoma cell line exerting both cytostatic and cytotoxic activities was also demonstrated.
基金supported by the National Key R&D Program of China(2020YFA0707600 and 2020YFC0841000)the National Natural Science Foundation of China(31970171 and 31670164)the Chinese Academy of Medical Sciences Innovation Fund for Medical Sciences(2016-12M-1-014 and 2020-12M-Co V19-010)。
文摘Bat coronavirus(CoV)RaTG13 shares the highest genome sequence identity with severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)among all known coronaviruses,and also uses human angiotensin converting enzyme 2(hACE2)for virus entry.Thus,SARS-CoV-2 is thought to have originated from bat.However,whether SARS-CoV-2 emerged from bats directly or through an intermediate host remains elusive.Here,we found that Rhinolophus affinis bat ACE2(Ra ACE2)is an entry receptor for both SARSCoV-2 and Ra TG13,although the binding of Ra ACE2 to the receptor-binding domain(RBD)of SARSCoV-2 is markedly weaker than that of h ACE2.We further evaluated the receptor activities of ACE2 s from additional 16 diverse animal species for Ra TG13,SARS-CoV,and SARS-CoV-2 in terms of S protein binding,membrane fusion,and pseudovirus entry.We found that the Ra TG13 spike(S)protein is significantly less fusogenic than SARS-CoV and SARS-CoV-2,and seven out of sixteen different ACE2 s function as entry receptors for all three viruses,indicating that all three viruses might have broad host rages.Of note,Ra TG13 S pseudovirions can use mouse,but not pangolin ACE2,for virus entry,whereas SARS-CoV-2 S pseudovirions can use pangolin,but not mouse,ACE2 enter cells efficiently.Mutagenesis analysis revealed that residues 484 and 498 in Ra TG13 and SARS-CoV-2 S proteins play critical roles in recognition of mouse and human ACE2 s.Finally,two polymorphous Rhinolophous sinicus bat ACE2 s showed different susceptibilities to virus entry by Ra TG13 and SARS-CoV-2 S pseudovirions,suggesting possible coevolution.Our results offer better understanding of the mechanism of coronavirus entry,host range,and virushost coevolution.
基金This work has been supported by Key Laboratory of Wood Industry and Furniture Engineering of Sichuan Provincial Colleges and Universities.
文摘In order to maintain soil fertility of Neosinocalamus affinis plantations,fertilizers of N,P,and K were applied.The anatomical and physical-mechanical properties of N.affinis bamboo wood from different fertilization treatments were measured.The aim of this study was to elucidate the effect of fertilization practice on the properties of N.affinis bamboo wood.The results revealed that the fertilization of P and K resulted in a slight reduction in fiber length.The application of P,K,and low level(0.3 kg/clump)of N fertilizers had no significant effect on the fiber morphology,while high level(0.9 kg/clump)of N fertilizer contributed to short fibers.The specific gravity was significantly decreased by fertilization,while the volume shrinkage was increased.Since the effect of various fertilization treatments had different influence patterns on the properties of N.affinis,specific evaluations on the quality of the fertilized bamboo wood should be performed prior to its utilization.
文摘Diflubenzuron (DFB, trade name dimilin 25 WP) is a chitin synthesis inhibitor widely used against forest insect pests in Algeria. Prior to implementation of these products as chemical agents for mosquito control, knowledge on their potential effects on non-target organisms and its behaviour in water are needed. Therefore, the present study was focused on DFB and aimed to use an HPLC procedure developed previously in order to obtain information on its degradation in freshwater and its bioconcentration in adult females of the fish Gambusia affinis (Cyprinodondiformes, Poeciliidae), which is one of the best candidates for biological control programs against mosquitoes. The adult females were exposed to dimilin (initial concentration 312 ng a.i./ml) for 28 days and residues analysis determined at different exposure times (0, 7, 14, 21 and 28 days). The concentration of DFB in freshwater decreased with exposure time while the amount of residues detected at the surface of the fish body increased progressively to reach a maximum at day 14 (162.7 ± 14.0 ng/fish) and declined thereafter during the exposure period. In addition, DFB incorporation into body increased with decreasing DFB concentration in water at each exposure time. The following average distribution was noted at the end of experiment (28 days): about 33% of the applied concentration was detected on the surface of fish body and was recovered by simple rinsing, and about 67% was found inside the fish body. A degradation in water and surface of fish occurred starting day 14 during the experimental period. Thus, about 40% of the initial concentration was degraded in freshwater after 28 days. The results are discussed to develop a better understanding of the degradation of dimilin in water and their potential effect on non-target organisms for its application for controlling mosquito.
