Lipid and sugar homeostasis is critical for insect development and survival.In this study,we characterized an acetyl coenzyme A carboxylase gene in Blattella germanica(BgACC)that is involved in both lipogenesis and su...Lipid and sugar homeostasis is critical for insect development and survival.In this study,we characterized an acetyl coenzyme A carboxylase gene in Blattella germanica(BgACC)that is involved in both lipogenesis and sugar homeostasis.We found that BgACC was dominantly expressed in the fat body and integument,and was significantly upregulated after molting.Knockdown of BgACC in 5th-instar nymphs did not affect their normal molting to the next nymphal stage,but it caused a lethal phenotype during adult emergence.BgACC-RNA interference(RNAi)significantly downregulated total free fatty acid(FFA)and triacylglycerol(TAG)levels,and also caused a significant decrease of cuticular hydrocarbons(CHCs).Repression of BgACC in adult females affected the development of oocytes and resulted in sterile females,but BgACC-RNAi did not affect the reproductive ability of males.Interestingly,knockdown of BgACC also changed the expression of insulin-like peptide genes(BglLPs),which mimicked a physiological state of high sugar uptake.In addition,BgACC was upregulated when B.germanica were fed on a high sucrose diet,and repression of BgACC upregulated the expression of the glycogen synthase gene(BgGlyS).Moreover,BgACC-RNAi increased the circulating sugar levels and glycogen storage,and a longevity assay suggested that BgACC was important for the survival of B.germanica under conditions of high sucrose uptake.Our results confirm that BgACC is involved in multiple lipid biogenesis and sugar homeostasis processes,which further modulates insect reproduction and sugar tolerance.This study benefits our understanding of the crosstalk between lipid and sugar metabolism.展开更多
High-density germanate glasses doped with Tb^(3+)ions were synthesized via the melt-quenching meth-od.The physical and luminescent properties of these glasses were characterized through various techniques,in-cluding d...High-density germanate glasses doped with Tb^(3+)ions were synthesized via the melt-quenching meth-od.The physical and luminescent properties of these glasses were characterized through various techniques,in-cluding density measurement,differential scanning calorimetry(DSC),photoluminescence(PL)spectroscopy,X-ray excited luminescence(XEL)spectroscopy,and fluorescence decay analysis.The densities of the germanate glasses were greater than 6.1 g/cm^(3).Upon excitations of ultraviolet(UV)light and X-rays,the glasses emitted in-tense green emissions.The fluorescence lifetime of the strongest emission peak at 544 nm,measured under 377 nm excitation,ranged from 1.52 ms to 1.32 ms.In the glass specimens,the maximum XEL integral intensity reached roughly 26%of that of the commercially available Bi_(4)Ge_(3)O_(12)(BGO)crystal.These results indicate that Tb^(3+)-doped high-density germanate scintillating glasses hold potential as scintillation materials for X-ray imaging applications.展开更多
In this paper,we provide two new Triassic palaeomagnetic poles from Winterswijk,the Netherlands,in the stable interior of the Eurasian plate.They were respectively collected from the Anisian(~247–242 Ma)red marly lim...In this paper,we provide two new Triassic palaeomagnetic poles from Winterswijk,the Netherlands,in the stable interior of the Eurasian plate.They were respectively collected from the Anisian(~247–242 Ma)red marly limestones of the sedimentary transition of the Buntsandstein Formation to the dark grey limestones of the basal Muschelkalk Formation,and from the Rhaetian(~208–201 Ma)shallow marine claystones that unconformably overlie the Muschelkalk Formation.The magnetization is carried by hematite or magnetite in the Anisian limestones,and iron sulfides and magnetite in the Rhaetian sedimentary rocks,revealing for both a large normal polarity overprint with a recent(geocentric axial dipole field)direction at the present latitude of the locality.Alternating field and thermal demagnetization occasionally reveal a stable magnetization decaying towards the origin,interpreted as the Characteristic Remanent Magnetization.Where we find a pervasive(normal polarity)overprint,we can often still determine well-defined great-circle solutions.Our interpreted palaeomagnetic poles include the great-circle solutions.The Anisian magnetic pole has declination D±ΔDx=210.8±3.0°,inclination I±ΔIx=-26.7±4.9°,with a latitude,longitude of 45.0°,142.0°respectively,K=43.9,A95=2.9°,N=56.The Rhaetian magnetic pole has declination D±ΔDx=32.0±8.7°,inclination I±ΔIx=50.9±8.1°,with a latitude,longitude of 60.6°,123.9°respectively,K=19.3,A95=7.4°,N=21.The poles plot close to the predicted location of global apparent polar wander paths(GAPWa Ps)in Eurasian coordinates and are feasible for future apparent polar wander path construction.They confirm that the intracontinental,shallow-marine Germanic Basin,in which the Muschelkalk Formation was deposited,existed at a palaeolatitude of 14.1°[11.3,17.1]N,in a palaeo-environment reminding of the Persian Gulf today.In Rhaetian times,palaeolatitudes of 31.6°[24.8,39.8]N were reached,on its way to the modern latitude of 52°N.展开更多
This study explores the application of Production-Oriented Approach(POA)in teaching German to nursing students in colleges and universities.Focusing on the requirements of the German B1 exam,the study takes the themat...This study explores the application of Production-Oriented Approach(POA)in teaching German to nursing students in colleges and universities.Focusing on the requirements of the German B1 exam,the study takes the thematic unit of“Movement”as an example,and designs the teaching through the links of“drive-enable-evaluate”.The results show that POA effectively improves students’speaking and writing output,but there are still deficiencies in reading and listening.Accordingly,this study has proposed the strategies of“vocabulary in-depth facilitation”and“accurate matching of listening and writing”to optimize the input materials and skills training,achieve the goal of“learning and using”,and provide a practical path for teaching German for Special Purposes.This provides a practical path for the teaching of German for special purposes.展开更多
AT No.1 Xiaofenqiao,Guangzhou Road,Nanjing,a grey-brick Western-style villa stands quietly in the green shade of dense plane trees.When the breeze stirs the leaves,they rustle as if whispering old stories.The two-stor...AT No.1 Xiaofenqiao,Guangzhou Road,Nanjing,a grey-brick Western-style villa stands quietly in the green shade of dense plane trees.When the breeze stirs the leaves,they rustle as if whispering old stories.The two-story house was the former residence of John Rabe(1882-1950),representative of German Siemens China Co.in Nanjing.展开更多
The full potential of advanced coating and finishingtechnologies for the production of technical textiles willbe outlined by Monforts specialists at Techtextil NorthAmerica which takes place in Atlanta,Georgia,from Ma...The full potential of advanced coating and finishingtechnologies for the production of technical textiles willbe outlined by Monforts specialists at Techtextil NorthAmerica which takes place in Atlanta,Georgia,from May6-8.The company and its US representative PSP Market-ing,of Charlotte,North Carolina,will be part of the exten-sive VDMA German Pavilion at the show,at stand 323lwithin the Georgia World Congress Center.展开更多
Open government-enterprise communication lies behind Qingdao’s success in attracting German investment.Aconducive business environment is crucial for stimulating economic vitality and driving high-quality development.
University German majors in Chinese universities constitute a vital force in cross-cultural communication and play an increasingly important role in effectively communicating China’s narrative to global audiences.Des...University German majors in Chinese universities constitute a vital force in cross-cultural communication and play an increasingly important role in effectively communicating China’s narrative to global audiences.Despite their linguistic advantages,these students still face challenges such as limited cultural literacy and insufficient intercultural communication competence.It is therefore essential to explore effective approaches for strengthening their ability to convey China’s narrative in accurate,compelling,and culturally attuned ways.This article discusses key pathways for enhancing this competence and offers insights relevant to curriculum development and talent cultivation in the field of international communication.展开更多
Water retention is critical for physiological homeostasis and survival in terrestrial insects. While deposition of hydrocarbons on insect cuticles as a key measure for water conservation has been extensively investiga...Water retention is critical for physiological homeostasis and survival in terrestrial insects. While deposition of hydrocarbons on insect cuticles as a key measure for water conservation has been extensively investigated, we know little about other mechanisms for preventing water loss in insects. Here, we report two fatty acid synthetic genes that are independent of hydrocarbon production but crucial for water retention in the German cockroach Blattella germanica (L.). First, an integument enriched fatty acid elongase gene (BgElo1) was identified as a critical gene for desiccation resistance in B. germanica;however, knockdown of BgElo1 surprisingly failed to cause a decline in cuticular lipids. In addition, RNA interference (RNAi)-knockdown of an upstream fatty acid synthase gene (BgFas3) showed a similar phenotype, and transmission electron microscopy analysis revealed that BgFas3- or BgElo1-RNAi did not affect cuticle architecture. Bodyweight loss test showed that repression of BgFas3 and BgElo1 significantly increased the weight loss rate, but the difference disappeared when the respiration was closed by freeze killing the cockroaches. A water immersion test was performed, and we found that BgFas3- and BgElo1-RNAi made it difficult for cockroaches to recover from drowning, which was supported by the upregulation of hypoxia-related genes after a 10-h recovery from drowning. Moreover, a dyeing assay with water-soluble Eosin Y showed that this was caused by the entry of water into the respiratory system. Our research suggests that BgFas3 and BgElo1 are required for both inward and outward waterproofing of the respiratory system. This study benefits the understanding of water retention mechanisms in insects.展开更多
Decisions made by foraging animals conform a complex process based on the integration of information from multiple external environmental stimuli and internal physiological signals,which in turn are modulated by indiv...Decisions made by foraging animals conform a complex process based on the integration of information from multiple external environmental stimuli and internal physiological signals,which in turn are modulated by individual experience and a detection threshold of each individual.For social insects in which foraging is limited to given age subcastes,individual foraging decisions may also be affected by ontogenetic shifts and colony requirements.We studied the short-term changes in foraging preferences of the generalist wasp Vespula germanica,focusing on whether the individual response to different resources could be influenced by the ontogenetic shifts and/or by social interaction with nestmates.We carried both laboratory and field experiments to confront worker wasps to a short-term resource switch between either protein or carbohydrate-based foods.We tested the response of(1)Preforager workers(no foraging experience nor interaction with other wasps),(2)Forager workers(experience in foraging and no colony feedback),and(3)Wild forager workers(foraging naturally and exposed to free interactions with nestmates).We evaluated the maxilla-labium extension response(MaLER)for laboratory assays or the landing response for field assays.We observed that for wasps deprived of colony feedback(either preforagers or foragers),the protein-rich foods acceptance threshold increased(and thus a lower level of foraging on that item was observed)if they had foraged on carbohydrates previously,whereas carbohydrates were accepted in all assays.However,wasps immersed in a natural foraging context did accept protein foods regardless of their first foraging experience and reduced the carbohydrates collected when trained on protein foods.We provide evidence that short-term changes in foraging preferences depend on the type of resource foraged and on the social interactions,but not on ontogenetic shifts.展开更多
Understanding the factors that affect animal dispersal behavior is important from both fi.mdamental and applied perspectives. Dispersal can have clear evolutionary and ecological consequences, but for normative insect...Understanding the factors that affect animal dispersal behavior is important from both fi.mdamental and applied perspectives. Dispersal can have clear evolutionary and ecological consequences, but for normative insect pests, dispersal capacity can also help to explain invasion success. Vespula germanica is a social wasp that, in the last century, has successfully invaded several regions of the world, showing one of the highest spread rates reported for a nonnative insect. In contrast with nonsocial wasps, in social species, queens are responsible for population redistribution and spread, as workers are sterile. For V. germanica, it has been observed that queen flight is limited to 2 distinct periods： early autumn, when new queens leave the nest to mate and find sheltered places in which to hibernate, and spring when new colonies are founded. Our aim was to study the flight behavior of V. germanica queens by focusing on the different periods in which dispersal occurs, characterizing as well the potential contribution of queen flight （i.e., distance） to the observed geographical spread. Our results suggest that the distances flown by nonover- wintered queens is greater than that flown by overwintered individuals, suggesting that the main queen dispersal events would occur before queens enter hibernation. This could relate to a behavioral trait of the queens to avoid the inbreeding with related drones. Additionally, given the short distances flown and remarkable geographical spread observed, we provide evidence showing that queen dispersal by flight is likely to contribute proportionately less to population spread than human-aided factors.展开更多
Melanin is involved in cuticle pigmentation and sclerotization of insects,which is critical for maintaining structural integrity and functional completeness of insect cuti-cle.The 2 key enzymes of tyrosine hydroxylase...Melanin is involved in cuticle pigmentation and sclerotization of insects,which is critical for maintaining structural integrity and functional completeness of insect cuti-cle.The 2 key enzymes of tyrosine hydroxylase(TH)and dopa decarboxylase(DDC)predicted in melanin biosynthesis are usually conserved in insects.However,it is unclear whether their function is related to epidermal permeability.In this study,we identified and cloned the gene sequences of BgTH and BgDdc from Blattella germanica,and revealed that they both showed a high expression at the molting,and BgTH was abundant in the head and integument while BgDdc was expressed highest in the fat body.Using RNA in-terference(RNAi),we found that knockdown of BgTH caused molting obstacles in some cockroaches,with the survivors showing pale color and softer integuments,while knock-down of BgDdc was viable and generated an abnormal light brown body color.Desiccation assay showed that the dsBgTH-injected adults died earlier than control groups under a dry atmosphere,but dsBgDdc-injected cockroaches did not.In contrast,when dsRNA-treated cockroaches were reared under a high humidity condition,almost no cockroaches died in all treatments.Furthermore,with eosin Y staining assay,we found that BgTH-RNAi resulted in a higher cuticular permeability,and BgDdc-RNAi also caused slight dye pen-etration.These results demonstrate that BgTH and BgDdc function in body pigmentation and affect the waterproofing ability of the cuticle,and the reduction of cuticular perme-ability may be achieved through cuticle melanization.展开更多
Ambroxol hydrochloride(2-amino-3,5-dibromo-N-methylbenzylamine hydrochloride)has been used as a mucolytic agent in the treatment of respiratory diseases since the late 1970s.Its effects on mucus membranes such as mucu...Ambroxol hydrochloride(2-amino-3,5-dibromo-N-methylbenzylamine hydrochloride)has been used as a mucolytic agent in the treatment of respiratory diseases since the late 1970s.Its effects on mucus membranes such as mucus disruption,increased mucus production,and low toxicity profile were addressed in its original German patent in 1966.These first described properties have kept Ambroxol available worldwide and over the counter in the pharmaceutical market to this day.展开更多
“Europe has missed this development opportunity because we are short of a long-term vision.”MORE than 40 exhibitors from 15 major vehicle brands around the world,representing the latest cutting-edge technologies and...“Europe has missed this development opportunity because we are short of a long-term vision.”MORE than 40 exhibitors from 15 major vehicle brands around the world,representing the latest cutting-edge technologies and models,gathered at the seventh China International Import Expo(CIIE),which was held in Shanghai from November 5 to 10.展开更多
In this exclusive interview,Michael Schumann,chairman of the Board of the German Federal Association for Economic Development and Foreign Trade,discusses Sino-German trade relations and the“out-of-proportion”debate ...In this exclusive interview,Michael Schumann,chairman of the Board of the German Federal Association for Economic Development and Foreign Trade,discusses Sino-German trade relations and the“out-of-proportion”debate on Xinjiang.展开更多
This research examines the characteristics of multimodal metaphors utilized by German advertisers in their commercial designs.Commercial advertisements inherently incorporate a diverse array of communicative symbols,e...This research examines the characteristics of multimodal metaphors utilized by German advertisers in their commercial designs.Commercial advertisements inherently incorporate a diverse array of communicative symbols,encompassing textual,visual,and auditory elements,which collaboratively function to construct metaphoric representations.Consequently,these advertisements are characterized by a rich presence of multimodal metaphors,strategically crafted to leave a lasting impression on viewers and to stimulate the purchasing intentions of targeted demographics.Employing a cognitive linguistics framework,this paper conducts a comparative analysis of the multimodal metaphors present in three exemplary German commercials:K-fee,Coca-Cola Zero,and Pure Milk.The findings illuminate the effective deployment of multimodal strategies in enhancing message transmission and fostering consumer engagement within the advertising landscape.展开更多
基金funded by the National Natural Science Foundation of China(32200384)the China Postdoctoral Science Foundation(2022M710053).
文摘Lipid and sugar homeostasis is critical for insect development and survival.In this study,we characterized an acetyl coenzyme A carboxylase gene in Blattella germanica(BgACC)that is involved in both lipogenesis and sugar homeostasis.We found that BgACC was dominantly expressed in the fat body and integument,and was significantly upregulated after molting.Knockdown of BgACC in 5th-instar nymphs did not affect their normal molting to the next nymphal stage,but it caused a lethal phenotype during adult emergence.BgACC-RNA interference(RNAi)significantly downregulated total free fatty acid(FFA)and triacylglycerol(TAG)levels,and also caused a significant decrease of cuticular hydrocarbons(CHCs).Repression of BgACC in adult females affected the development of oocytes and resulted in sterile females,but BgACC-RNAi did not affect the reproductive ability of males.Interestingly,knockdown of BgACC also changed the expression of insulin-like peptide genes(BglLPs),which mimicked a physiological state of high sugar uptake.In addition,BgACC was upregulated when B.germanica were fed on a high sucrose diet,and repression of BgACC upregulated the expression of the glycogen synthase gene(BgGlyS).Moreover,BgACC-RNAi increased the circulating sugar levels and glycogen storage,and a longevity assay suggested that BgACC was important for the survival of B.germanica under conditions of high sucrose uptake.Our results confirm that BgACC is involved in multiple lipid biogenesis and sugar homeostasis processes,which further modulates insect reproduction and sugar tolerance.This study benefits our understanding of the crosstalk between lipid and sugar metabolism.
文摘High-density germanate glasses doped with Tb^(3+)ions were synthesized via the melt-quenching meth-od.The physical and luminescent properties of these glasses were characterized through various techniques,in-cluding density measurement,differential scanning calorimetry(DSC),photoluminescence(PL)spectroscopy,X-ray excited luminescence(XEL)spectroscopy,and fluorescence decay analysis.The densities of the germanate glasses were greater than 6.1 g/cm^(3).Upon excitations of ultraviolet(UV)light and X-rays,the glasses emitted in-tense green emissions.The fluorescence lifetime of the strongest emission peak at 544 nm,measured under 377 nm excitation,ranged from 1.52 ms to 1.32 ms.In the glass specimens,the maximum XEL integral intensity reached roughly 26%of that of the commercially available Bi_(4)Ge_(3)O_(12)(BGO)crystal.These results indicate that Tb^(3+)-doped high-density germanate scintillating glasses hold potential as scintillation materials for X-ray imaging applications.
基金funded through NWO Vidi Grant 864.11.004and NWO Vici Grant 865.17.001
文摘In this paper,we provide two new Triassic palaeomagnetic poles from Winterswijk,the Netherlands,in the stable interior of the Eurasian plate.They were respectively collected from the Anisian(~247–242 Ma)red marly limestones of the sedimentary transition of the Buntsandstein Formation to the dark grey limestones of the basal Muschelkalk Formation,and from the Rhaetian(~208–201 Ma)shallow marine claystones that unconformably overlie the Muschelkalk Formation.The magnetization is carried by hematite or magnetite in the Anisian limestones,and iron sulfides and magnetite in the Rhaetian sedimentary rocks,revealing for both a large normal polarity overprint with a recent(geocentric axial dipole field)direction at the present latitude of the locality.Alternating field and thermal demagnetization occasionally reveal a stable magnetization decaying towards the origin,interpreted as the Characteristic Remanent Magnetization.Where we find a pervasive(normal polarity)overprint,we can often still determine well-defined great-circle solutions.Our interpreted palaeomagnetic poles include the great-circle solutions.The Anisian magnetic pole has declination D±ΔDx=210.8±3.0°,inclination I±ΔIx=-26.7±4.9°,with a latitude,longitude of 45.0°,142.0°respectively,K=43.9,A95=2.9°,N=56.The Rhaetian magnetic pole has declination D±ΔDx=32.0±8.7°,inclination I±ΔIx=50.9±8.1°,with a latitude,longitude of 60.6°,123.9°respectively,K=19.3,A95=7.4°,N=21.The poles plot close to the predicted location of global apparent polar wander paths(GAPWa Ps)in Eurasian coordinates and are feasible for future apparent polar wander path construction.They confirm that the intracontinental,shallow-marine Germanic Basin,in which the Muschelkalk Formation was deposited,existed at a palaeolatitude of 14.1°[11.3,17.1]N,in a palaeo-environment reminding of the Persian Gulf today.In Rhaetian times,palaeolatitudes of 31.6°[24.8,39.8]N were reached,on its way to the modern latitude of 52°N.
文摘This study explores the application of Production-Oriented Approach(POA)in teaching German to nursing students in colleges and universities.Focusing on the requirements of the German B1 exam,the study takes the thematic unit of“Movement”as an example,and designs the teaching through the links of“drive-enable-evaluate”.The results show that POA effectively improves students’speaking and writing output,but there are still deficiencies in reading and listening.Accordingly,this study has proposed the strategies of“vocabulary in-depth facilitation”and“accurate matching of listening and writing”to optimize the input materials and skills training,achieve the goal of“learning and using”,and provide a practical path for teaching German for Special Purposes.This provides a practical path for the teaching of German for special purposes.
文摘AT No.1 Xiaofenqiao,Guangzhou Road,Nanjing,a grey-brick Western-style villa stands quietly in the green shade of dense plane trees.When the breeze stirs the leaves,they rustle as if whispering old stories.The two-story house was the former residence of John Rabe(1882-1950),representative of German Siemens China Co.in Nanjing.
文摘The full potential of advanced coating and finishingtechnologies for the production of technical textiles willbe outlined by Monforts specialists at Techtextil NorthAmerica which takes place in Atlanta,Georgia,from May6-8.The company and its US representative PSP Market-ing,of Charlotte,North Carolina,will be part of the exten-sive VDMA German Pavilion at the show,at stand 323lwithin the Georgia World Congress Center.
文摘Open government-enterprise communication lies behind Qingdao’s success in attracting German investment.Aconducive business environment is crucial for stimulating economic vitality and driving high-quality development.
文摘University German majors in Chinese universities constitute a vital force in cross-cultural communication and play an increasingly important role in effectively communicating China’s narrative to global audiences.Despite their linguistic advantages,these students still face challenges such as limited cultural literacy and insufficient intercultural communication competence.It is therefore essential to explore effective approaches for strengthening their ability to convey China’s narrative in accurate,compelling,and culturally attuned ways.This article discusses key pathways for enhancing this competence and offers insights relevant to curriculum development and talent cultivation in the field of international communication.
基金This work was supported by the National Natural Science Foundation of China(Grant No.31772533).
文摘Water retention is critical for physiological homeostasis and survival in terrestrial insects. While deposition of hydrocarbons on insect cuticles as a key measure for water conservation has been extensively investigated, we know little about other mechanisms for preventing water loss in insects. Here, we report two fatty acid synthetic genes that are independent of hydrocarbon production but crucial for water retention in the German cockroach Blattella germanica (L.). First, an integument enriched fatty acid elongase gene (BgElo1) was identified as a critical gene for desiccation resistance in B. germanica;however, knockdown of BgElo1 surprisingly failed to cause a decline in cuticular lipids. In addition, RNA interference (RNAi)-knockdown of an upstream fatty acid synthase gene (BgFas3) showed a similar phenotype, and transmission electron microscopy analysis revealed that BgFas3- or BgElo1-RNAi did not affect cuticle architecture. Bodyweight loss test showed that repression of BgFas3 and BgElo1 significantly increased the weight loss rate, but the difference disappeared when the respiration was closed by freeze killing the cockroaches. A water immersion test was performed, and we found that BgFas3- and BgElo1-RNAi made it difficult for cockroaches to recover from drowning, which was supported by the upregulation of hypoxia-related genes after a 10-h recovery from drowning. Moreover, a dyeing assay with water-soluble Eosin Y showed that this was caused by the entry of water into the respiratory system. Our research suggests that BgFas3 and BgElo1 are required for both inward and outward waterproofing of the respiratory system. This study benefits the understanding of water retention mechanisms in insects.
基金support from the Instituto de Investigaciones Forestales y Agropecuarias Bariloche(IFAB)This study was financed by project BID PICT 2015-1150 provided by the "Agencia Nacional de Promocion Cientifica y Tecno-logica"(Argentina),project PUE 00692018-IFAB and project B215 from the Universidad Nacional del Comahue,Centro Regional Universitario Bariloche.
文摘Decisions made by foraging animals conform a complex process based on the integration of information from multiple external environmental stimuli and internal physiological signals,which in turn are modulated by individual experience and a detection threshold of each individual.For social insects in which foraging is limited to given age subcastes,individual foraging decisions may also be affected by ontogenetic shifts and colony requirements.We studied the short-term changes in foraging preferences of the generalist wasp Vespula germanica,focusing on whether the individual response to different resources could be influenced by the ontogenetic shifts and/or by social interaction with nestmates.We carried both laboratory and field experiments to confront worker wasps to a short-term resource switch between either protein or carbohydrate-based foods.We tested the response of(1)Preforager workers(no foraging experience nor interaction with other wasps),(2)Forager workers(experience in foraging and no colony feedback),and(3)Wild forager workers(foraging naturally and exposed to free interactions with nestmates).We evaluated the maxilla-labium extension response(MaLER)for laboratory assays or the landing response for field assays.We observed that for wasps deprived of colony feedback(either preforagers or foragers),the protein-rich foods acceptance threshold increased(and thus a lower level of foraging on that item was observed)if they had foraged on carbohydrates previously,whereas carbohydrates were accepted in all assays.However,wasps immersed in a natural foraging context did accept protein foods regardless of their first foraging experience and reduced the carbohydrates collected when trained on protein foods.We provide evidence that short-term changes in foraging preferences depend on the type of resource foraged and on the social interactions,but not on ontogenetic shifts.
文摘Understanding the factors that affect animal dispersal behavior is important from both fi.mdamental and applied perspectives. Dispersal can have clear evolutionary and ecological consequences, but for normative insect pests, dispersal capacity can also help to explain invasion success. Vespula germanica is a social wasp that, in the last century, has successfully invaded several regions of the world, showing one of the highest spread rates reported for a nonnative insect. In contrast with nonsocial wasps, in social species, queens are responsible for population redistribution and spread, as workers are sterile. For V. germanica, it has been observed that queen flight is limited to 2 distinct periods： early autumn, when new queens leave the nest to mate and find sheltered places in which to hibernate, and spring when new colonies are founded. Our aim was to study the flight behavior of V. germanica queens by focusing on the different periods in which dispersal occurs, characterizing as well the potential contribution of queen flight （i.e., distance） to the observed geographical spread. Our results suggest that the distances flown by nonover- wintered queens is greater than that flown by overwintered individuals, suggesting that the main queen dispersal events would occur before queens enter hibernation. This could relate to a behavioral trait of the queens to avoid the inbreeding with related drones. Additionally, given the short distances flown and remarkable geographical spread observed, we provide evidence showing that queen dispersal by flight is likely to contribute proportionately less to population spread than human-aided factors.
基金supported by the National Natural Science Foundation of China(grant no.31772533)。
文摘Melanin is involved in cuticle pigmentation and sclerotization of insects,which is critical for maintaining structural integrity and functional completeness of insect cuti-cle.The 2 key enzymes of tyrosine hydroxylase(TH)and dopa decarboxylase(DDC)predicted in melanin biosynthesis are usually conserved in insects.However,it is unclear whether their function is related to epidermal permeability.In this study,we identified and cloned the gene sequences of BgTH and BgDdc from Blattella germanica,and revealed that they both showed a high expression at the molting,and BgTH was abundant in the head and integument while BgDdc was expressed highest in the fat body.Using RNA in-terference(RNAi),we found that knockdown of BgTH caused molting obstacles in some cockroaches,with the survivors showing pale color and softer integuments,while knock-down of BgDdc was viable and generated an abnormal light brown body color.Desiccation assay showed that the dsBgTH-injected adults died earlier than control groups under a dry atmosphere,but dsBgDdc-injected cockroaches did not.In contrast,when dsRNA-treated cockroaches were reared under a high humidity condition,almost no cockroaches died in all treatments.Furthermore,with eosin Y staining assay,we found that BgTH-RNAi resulted in a higher cuticular permeability,and BgDdc-RNAi also caused slight dye pen-etration.These results demonstrate that BgTH and BgDdc function in body pigmentation and affect the waterproofing ability of the cuticle,and the reduction of cuticular perme-ability may be achieved through cuticle melanization.
基金partly funded by the Clinician-Scientist grant(No.472-0-0)by the medical faculty of the University of Tübingen(to SCV).
文摘Ambroxol hydrochloride(2-amino-3,5-dibromo-N-methylbenzylamine hydrochloride)has been used as a mucolytic agent in the treatment of respiratory diseases since the late 1970s.Its effects on mucus membranes such as mucus disruption,increased mucus production,and low toxicity profile were addressed in its original German patent in 1966.These first described properties have kept Ambroxol available worldwide and over the counter in the pharmaceutical market to this day.
文摘“Europe has missed this development opportunity because we are short of a long-term vision.”MORE than 40 exhibitors from 15 major vehicle brands around the world,representing the latest cutting-edge technologies and models,gathered at the seventh China International Import Expo(CIIE),which was held in Shanghai from November 5 to 10.
文摘In this exclusive interview,Michael Schumann,chairman of the Board of the German Federal Association for Economic Development and Foreign Trade,discusses Sino-German trade relations and the“out-of-proportion”debate on Xinjiang.
文摘This research examines the characteristics of multimodal metaphors utilized by German advertisers in their commercial designs.Commercial advertisements inherently incorporate a diverse array of communicative symbols,encompassing textual,visual,and auditory elements,which collaboratively function to construct metaphoric representations.Consequently,these advertisements are characterized by a rich presence of multimodal metaphors,strategically crafted to leave a lasting impression on viewers and to stimulate the purchasing intentions of targeted demographics.Employing a cognitive linguistics framework,this paper conducts a comparative analysis of the multimodal metaphors present in three exemplary German commercials:K-fee,Coca-Cola Zero,and Pure Milk.The findings illuminate the effective deployment of multimodal strategies in enhancing message transmission and fostering consumer engagement within the advertising landscape.
