As researchers have gained a better understanding in recent years into the physiological, molecular, and genetic basis of how plants deal with aluminum （AI） toxicity in acid soils prevalent in the tropics and sub-tr...As researchers have gained a better understanding in recent years into the physiological, molecular, and genetic basis of how plants deal with aluminum （AI） toxicity in acid soils prevalent in the tropics and sub-tropics, it has become clear that an important component of these responses is the triggering and regulation of cellular pathways and processes by AI. In this review of plant AI signaling, we begin by summarizing the understanding of physiological mechanisms of AI resistance, which first led researchers to realize that AI stress induces gene expression and modifies protein function during the activation of AI resistance responses. Subsequently, an overview of AI resistance genes and their function provides verification that AI induction of gene expression plays a major role in AI resistance in many plant species. More recent research into the mechanistic basis for Al-induced transcrip- tional activation of resistance genes has led to the identifica- tion of several transcription factors as well as cis-elements in the promoters of AI resistance genes that play a role in greater Al-induced gene expression as well as higher constitutive expression of resistance genes in some plant species. Finally, the post-transcriptional and translational regulation of AI resistance proteins is addressed, where recent research has shown that AI can both directly bind to and alter activity of certain organic acid transporters, and also influence AI resistance proteins indirectly, via protein phosphorylation.展开更多
植物产生大量的次生代谢物,不但对植物自身适应性具有极其重要的作用,而且有着巨大的实用价值。次生代谢物的跨膜转运是植物次生代谢工程研究的一个新兴领域。ABC(ATP-binding cassette)和MATE(multidrug and toxin extrusion)转运蛋白...植物产生大量的次生代谢物,不但对植物自身适应性具有极其重要的作用,而且有着巨大的实用价值。次生代谢物的跨膜转运是植物次生代谢工程研究的一个新兴领域。ABC(ATP-binding cassette)和MATE(multidrug and toxin extrusion)转运蛋白与生物体内多种物质的跨膜转运有关,在植物次生代谢物的运输过程中均发挥着重要作用。文章主要综述了ABC和MATE转运蛋白在植物次生代谢物跨膜转运中的研究进展。展开更多
A mechanical assembly is a composition of interrelated parts. Assembly data base stores the geometric models of indi-vidual parts, the spatial positions and orientations of the parts in the assembly, and the relations...A mechanical assembly is a composition of interrelated parts. Assembly data base stores the geometric models of indi-vidual parts, the spatial positions and orientations of the parts in the assembly, and the relationships between parts. An assembly of parts can be represented by its liaison which has a description of its relationships between the various parts in the assembly. The problem is to not only make the information available but also use the relevant information for making decisions, especially determination of the assembly sequence plan. The method described in this paper ex-tracts the feature based assembly information from CAD models of products and build up liaisons to facilitate assembly planning applications. The system works on the assumption that the designer explicitly defines joints and mating condi-tions. Further, a computer representation of mechanical assemblies in the form of liaisons is necessary in order to automate the generation of assembly plans. A novel method of extracting the assembly information and representing them in the form of liaisons is presented in this paper.展开更多
In this paper,making use of upper and lower solutions,we first prove the existence of the solu tion for integral differential equation of Volterra type.Then applying the theory of differential in equalities obtained,u...In this paper,making use of upper and lower solutions,we first prove the existence of the solu tion for integral differential equation of Volterra type.Then applying the theory of differential in equalities obtained,under the appropriate assumptions,by constructing the special function of upper and lower solutions,we demonstrate the existence of the solution for singularly preturbed integral differential equation of Volterra type,and give the uniformly valid approximate estimation.展开更多
The influence of female age on male mating preference and reproductive success has been studied using a promiscuous cabbage beetle, Colaphellus bowringi Baly （Coleoptera： Chrysomelidae）. In a simultaneous choice te...The influence of female age on male mating preference and reproductive success has been studied using a promiscuous cabbage beetle, Colaphellus bowringi Baly （Coleoptera： Chrysomelidae）. In a simultaneous choice test, middle-aged females had significantly greater mating success than young and old females. In single pair trials, when paired with middle-aged virgin males, middle-aged females mated faster, copulated longer, and had greater fecundity and fertility than young or old females, while the longevity of males was not significantly affected by female age. This study on C. bowringi suggests that middle-aged females are more receptive to mating, which can result in the highest male reproductive success.展开更多
This study investigated the effects of yerba mate consumption, a South American beverage, on cardiac remodeling in rats. For this purpose, 24 male Wistar rats were divided into Control Group (CG) which received filter...This study investigated the effects of yerba mate consumption, a South American beverage, on cardiac remodeling in rats. For this purpose, 24 male Wistar rats were divided into Control Group (CG) which received filtered water and a standard diet, and Yerba Mate Group (YM), 6 g of Ilex paraguariensis in 100 ml water and the same diet, for 30 days. The YM group showed a reduction in final body weight and food consumption without altering weight gain. Regarding cardiac remodeling, the YM group exhibited a decrease in the right ventricle weight/final body weight ratio, suggesting cardiac atrophy, without affecting the atria and left ventricle. There was no change in cardiomyocyte area or nuclear fractal dimension in both groups. However, animals that consumed yerba mate showed increased collagen deposition and a smaller fractal dimension in the left ventricle. The consumption of yerba mate at room temperature for 30 days induced changes in cardiac remodeling, as evidenced by increased collagen deposition and alterations in fractal dimension in the left ventricle.展开更多
Carbon fiber reinforced concrete(CFRC) was found to be anintrinsically smart material. An experi- mental study is presented toexamine the influence of size effect and loading rate on thepressure-sensitivity of CFRC du...Carbon fiber reinforced concrete(CFRC) was found to be anintrinsically smart material. An experi- mental study is presented toexamine the influence of size effect and loading rate on thepressure-sensitivity of CFRC during the elastic regime. The resultsshow that the sensitiv- ity increases with the size of specimenincreasing and load- ing rate makes no influence on it. The former isbecause the deformation of higher specimen is larger than lower oneunder the same compressive stress. The behind is because thedeformation of specimen is the same under the same com- pressivestress although the loading rate is different. Therefore, the smartbeharvior of CFRC also reflects the Deformation of material undercompressive stress.展开更多
Theory predicts that males and females of dioecious species typically engage in an evolutionary sexual conflict over the frequency and choice of mating partner.Female sexual cannibalism,a particularly dramatic illustr...Theory predicts that males and females of dioecious species typically engage in an evolutionary sexual conflict over the frequency and choice of mating partner.Female sexual cannibalism,a particularly dramatic illustration of this conflict,is widespread in certain animal taxa including spiders.Nevertheless,females of some funnel weaving spiders that are generally aggressive to conspecifics enter a cataleptic state after male courtship,ensuring the males can mate without risk of attack.In this study,we demonstrated that the physical posture and duration,metabo-lites,and central neurotransmitters of females of Aterigena aculeata in sexual catalepsy closely resemble females in thanatosis but are distinct from those in anesthesia,indicating that the courted females feign death to eliminate the risk of potentially aggressive responses and thereby allow preferred males to mate.Unlike the taxonomically widespread thanatosis,which generally represents a deceptive visual signal that acts against the interest of the receivers,sexual catalepsy of females in the funnel weaving spiders may deliver a sexual-receptive signal to the courting males and thereby benefit both the signal senders and receivers.Therefore,sexual catalepsy in A.aculeata may not reflect a conflict butrather a confluence of interest betweenthe sexes.展开更多
Plant multidrug and toxic compound extrusion(MATE) genes play an important role in the process of detoxification, plant morphogenesis, and anthocyanin accumulation. However, whether the MATE gene family functions in p...Plant multidrug and toxic compound extrusion(MATE) genes play an important role in the process of detoxification, plant morphogenesis, and anthocyanin accumulation. However, whether the MATE gene family functions in pear peel coloration is still unknown. To evaluate and identify the MATE gene family members which are involving in anthocyanin accumulation and coloration in pear. In this study, 85 MATE genes were identified in the reference pear genome of ‘Dangshansuli’ through genome-wide identification. Based on gene structure and phylogenetic tree analysis, the MATE family was divided into five subfamilies. RNA sequencing and quantitative real-time polymerase chain reaction(qRTPCR) indicated that the expression patterns of PbrMATEs were tissue-specific. 28.24%(24) of PbrMATE genes were expressed in the fruits, and44.71%(38) of PbrMATE genes were expressed in the leaves. Additionally, we found that the expression levels of PbrMATE9, PbrMATE26,PbrMATE50, and PbrMATE69 in debagged fruits with red peel were significantly higher than those in bagged fruits without red peel, according to our bagging/debagging treatment of ‘Mantianhong’. The expression pattern of PbrMATE9 was consistent with the variation trend in anthocyanin content, suggesting that it might play an important role in anthocyanin accumulation in response to light exposure. Subcellular localization showed that PbrMATE9 was a membrane protein. More strikingly, the transient overexpression of PbrMATE9 promoted anthocyanin accumulation in the peel of pear, and the expression of structural genes(PbrCHI, PbrANS, PbrDFR, and PbrUFGT) in the anthocyanin biosynthesis pathway also increased significantly. Through co-expression network analysis, the transcription factors were identified, such as WRKY, COL,GATA, and BBX, which might be involved in the regulation of PbrMATE9. The study has enriched the genetic resources and improved the understanding of the regulation network of anthocyanin accumulation in pear.展开更多
The environment can impose strong limitations on the efficacy of signal transmission. In particular, for vibratory communication, the signaling environment is often extremely heterogeneous at small scales. Nevertheles...The environment can impose strong limitations on the efficacy of signal transmission. In particular, for vibratory communication, the signaling environment is often extremely heterogeneous at small scales. Nevertheless, natural selection is expected to select for signals well-suited for effective transmission. Here, we test for substrate-dependent signal efficacy in the wolf spider Schizocosa stridulans Strattou 1991. We first explore the transmission characteristics of this important signaling mo- dality by playing recorded substrate-bome signals through three different substrates （leaf litter, pine litter, and red clay） and measuring the propagated signal. We found that the substrate-bome signal of S. stridulans attenuates the least on leaf litter, the substrate upon which the species is naturally found. Next, by assessing mating success with artificially muted and non-muted males across different signaling substrates （leaf litter, pine litter, and sand）, we explored the relationship between substrate-bome signaling and signaling substrate for mating success. We found that muted males were unsuccessful in obtaining copulations re- gardless of substrate, while mating success was dependent on the signaling substrate for non-muted males. For non-muted males, more males copulated on leaf litter than any other substrate. Taken together, these results confLrm the importance of sub- strate-bome signaling in S. stridulans and suggest a match between signal properties and signal efficacy - leaf litter transmits the signal most effectively and males are most successful in obtaining copulations on leaf litter [Current Zoology 56 （3）： 370-378, 2010].展开更多
Large-scale and mesoscale analyses are made for extremely heavy rain (EHR) and meso-β scale low vortex (MSLV) in Jiading District of Shanghai Municipality during 6-7 July 2001.It is shown that the EHR forms in the si...Large-scale and mesoscale analyses are made for extremely heavy rain (EHR) and meso-β scale low vortex (MSLV) in Jiading District of Shanghai Municipality during 6-7 July 2001.It is shown that the EHR forms in the situation of northern westerly trough linking together with southern inverted typhoon trough at northwest side of the West Pacific Ocean subtropical high. Numerical simulation is made using a 21-layer improved REM (regional η coordinate model) for this course.The results show that the precipitation forms earlier than MSLV.and the strong convergence in wind velocity mate (WVM) triggers the strong precipitation.The formative reasons of WVM.especially the weak wind velocity center are discussed,and the formative mechanisms of the MSLV and EHR are discussed using high spatial and temporal resolution model- output physical fields.The results show that the heavy rain releases latent heat and warms the air column,and enhances the low level positive vorticity that existed before.Then it causes the formation of MSLV.There is a positive feedback mechanism between low vortex and precipitation,so CISK must be an important mechanism.展开更多
The role of female sex pheromones in natural selection, particularly as a means for species recognition to avoid the generation of hybrid offspring with low fitness, has been widely explored and is generally accepted ...The role of female sex pheromones in natural selection, particularly as a means for species recognition to avoid the generation of hybrid offspring with low fitness, has been widely explored and is generally accepted by scholars. However, the significance of sex pheromones in shaping mate choice （sexual selection） and in competition over breeding resources （social se- lection） has been largely ignored. The effect of sexual selection on sex pheromones as a sexually dimorphic signaling trait has been discounted because the amount of pheromone released by females is typically minute, while the role of sex pheromones in competition over breeding resources （other than mates） has not yet been considered. As a result of natural selection, variation in sex pheromones among females is expected to be low, and males are not expected to choose their mates among phero- mone-releasing conspecific females. Sexual selection, on the other hand, should drive the increase in pheromone variance among females, and males are expected to choose females based on this variation. Moreover, social selection resulting from more general social interactions, for example competition among females for breeding sites and food, should also promote variance among female sex pheromones. Here, we review the cttrrent evidence for each of the three selection processes acting on sex pheromones of female moths as an advertising trait. We suggest that the three selection types are not mutually exclusive but rather act together to promote different fimess components in diverse ecological situations展开更多
文摘As researchers have gained a better understanding in recent years into the physiological, molecular, and genetic basis of how plants deal with aluminum （AI） toxicity in acid soils prevalent in the tropics and sub-tropics, it has become clear that an important component of these responses is the triggering and regulation of cellular pathways and processes by AI. In this review of plant AI signaling, we begin by summarizing the understanding of physiological mechanisms of AI resistance, which first led researchers to realize that AI stress induces gene expression and modifies protein function during the activation of AI resistance responses. Subsequently, an overview of AI resistance genes and their function provides verification that AI induction of gene expression plays a major role in AI resistance in many plant species. More recent research into the mechanistic basis for Al-induced transcrip- tional activation of resistance genes has led to the identifica- tion of several transcription factors as well as cis-elements in the promoters of AI resistance genes that play a role in greater Al-induced gene expression as well as higher constitutive expression of resistance genes in some plant species. Finally, the post-transcriptional and translational regulation of AI resistance proteins is addressed, where recent research has shown that AI can both directly bind to and alter activity of certain organic acid transporters, and also influence AI resistance proteins indirectly, via protein phosphorylation.
文摘植物产生大量的次生代谢物,不但对植物自身适应性具有极其重要的作用,而且有着巨大的实用价值。次生代谢物的跨膜转运是植物次生代谢工程研究的一个新兴领域。ABC(ATP-binding cassette)和MATE(multidrug and toxin extrusion)转运蛋白与生物体内多种物质的跨膜转运有关,在植物次生代谢物的运输过程中均发挥着重要作用。文章主要综述了ABC和MATE转运蛋白在植物次生代谢物跨膜转运中的研究进展。
文摘A mechanical assembly is a composition of interrelated parts. Assembly data base stores the geometric models of indi-vidual parts, the spatial positions and orientations of the parts in the assembly, and the relationships between parts. An assembly of parts can be represented by its liaison which has a description of its relationships between the various parts in the assembly. The problem is to not only make the information available but also use the relevant information for making decisions, especially determination of the assembly sequence plan. The method described in this paper ex-tracts the feature based assembly information from CAD models of products and build up liaisons to facilitate assembly planning applications. The system works on the assumption that the designer explicitly defines joints and mating condi-tions. Further, a computer representation of mechanical assemblies in the form of liaisons is necessary in order to automate the generation of assembly plans. A novel method of extracting the assembly information and representing them in the form of liaisons is presented in this paper.
文摘In this paper,making use of upper and lower solutions,we first prove the existence of the solu tion for integral differential equation of Volterra type.Then applying the theory of differential in equalities obtained,under the appropriate assumptions,by constructing the special function of upper and lower solutions,we demonstrate the existence of the solution for singularly preturbed integral differential equation of Volterra type,and give the uniformly valid approximate estimation.
文摘The influence of female age on male mating preference and reproductive success has been studied using a promiscuous cabbage beetle, Colaphellus bowringi Baly （Coleoptera： Chrysomelidae）. In a simultaneous choice test, middle-aged females had significantly greater mating success than young and old females. In single pair trials, when paired with middle-aged virgin males, middle-aged females mated faster, copulated longer, and had greater fecundity and fertility than young or old females, while the longevity of males was not significantly affected by female age. This study on C. bowringi suggests that middle-aged females are more receptive to mating, which can result in the highest male reproductive success.
文摘This study investigated the effects of yerba mate consumption, a South American beverage, on cardiac remodeling in rats. For this purpose, 24 male Wistar rats were divided into Control Group (CG) which received filtered water and a standard diet, and Yerba Mate Group (YM), 6 g of Ilex paraguariensis in 100 ml water and the same diet, for 30 days. The YM group showed a reduction in final body weight and food consumption without altering weight gain. Regarding cardiac remodeling, the YM group exhibited a decrease in the right ventricle weight/final body weight ratio, suggesting cardiac atrophy, without affecting the atria and left ventricle. There was no change in cardiomyocyte area or nuclear fractal dimension in both groups. However, animals that consumed yerba mate showed increased collagen deposition and a smaller fractal dimension in the left ventricle. The consumption of yerba mate at room temperature for 30 days induced changes in cardiac remodeling, as evidenced by increased collagen deposition and alterations in fractal dimension in the left ventricle.
基金National Natural Science Foundation Kev Prciect No.59432061
文摘Carbon fiber reinforced concrete(CFRC) was found to be anintrinsically smart material. An experi- mental study is presented toexamine the influence of size effect and loading rate on thepressure-sensitivity of CFRC during the elastic regime. The resultsshow that the sensitiv- ity increases with the size of specimenincreasing and load- ing rate makes no influence on it. The former isbecause the deformation of higher specimen is larger than lower oneunder the same compressive stress. The behind is because thedeformation of specimen is the same under the same com- pressivestress although the loading rate is different. Therefore, the smartbeharvior of CFRC also reflects the Deformation of material undercompressive stress.
基金supported by Natural Science Foundation of China(no.32160243,no.32000301,no.32070429,no.31772423,no.82173799)the Science and Technology Foundation of Jiangxi Provincial Department of Education(no.GJJ190543).
文摘Theory predicts that males and females of dioecious species typically engage in an evolutionary sexual conflict over the frequency and choice of mating partner.Female sexual cannibalism,a particularly dramatic illustration of this conflict,is widespread in certain animal taxa including spiders.Nevertheless,females of some funnel weaving spiders that are generally aggressive to conspecifics enter a cataleptic state after male courtship,ensuring the males can mate without risk of attack.In this study,we demonstrated that the physical posture and duration,metabo-lites,and central neurotransmitters of females of Aterigena aculeata in sexual catalepsy closely resemble females in thanatosis but are distinct from those in anesthesia,indicating that the courted females feign death to eliminate the risk of potentially aggressive responses and thereby allow preferred males to mate.Unlike the taxonomically widespread thanatosis,which generally represents a deceptive visual signal that acts against the interest of the receivers,sexual catalepsy of females in the funnel weaving spiders may deliver a sexual-receptive signal to the courting males and thereby benefit both the signal senders and receivers.Therefore,sexual catalepsy in A.aculeata may not reflect a conflict butrather a confluence of interest betweenthe sexes.
基金supported by the National Natural Science Foundation of China (Grant No. 31820103012)the Earmarked Fund for China Agriculture Research System (Grant No. CARS-28)the Earmarked Fund for Jiangsu Agricultural Industry Technology System [Grant No. JATS (2022)454]。
文摘Plant multidrug and toxic compound extrusion(MATE) genes play an important role in the process of detoxification, plant morphogenesis, and anthocyanin accumulation. However, whether the MATE gene family functions in pear peel coloration is still unknown. To evaluate and identify the MATE gene family members which are involving in anthocyanin accumulation and coloration in pear. In this study, 85 MATE genes were identified in the reference pear genome of ‘Dangshansuli’ through genome-wide identification. Based on gene structure and phylogenetic tree analysis, the MATE family was divided into five subfamilies. RNA sequencing and quantitative real-time polymerase chain reaction(qRTPCR) indicated that the expression patterns of PbrMATEs were tissue-specific. 28.24%(24) of PbrMATE genes were expressed in the fruits, and44.71%(38) of PbrMATE genes were expressed in the leaves. Additionally, we found that the expression levels of PbrMATE9, PbrMATE26,PbrMATE50, and PbrMATE69 in debagged fruits with red peel were significantly higher than those in bagged fruits without red peel, according to our bagging/debagging treatment of ‘Mantianhong’. The expression pattern of PbrMATE9 was consistent with the variation trend in anthocyanin content, suggesting that it might play an important role in anthocyanin accumulation in response to light exposure. Subcellular localization showed that PbrMATE9 was a membrane protein. More strikingly, the transient overexpression of PbrMATE9 promoted anthocyanin accumulation in the peel of pear, and the expression of structural genes(PbrCHI, PbrANS, PbrDFR, and PbrUFGT) in the anthocyanin biosynthesis pathway also increased significantly. Through co-expression network analysis, the transcription factors were identified, such as WRKY, COL,GATA, and BBX, which might be involved in the regulation of PbrMATE9. The study has enriched the genetic resources and improved the understanding of the regulation network of anthocyanin accumulation in pear.
基金National Science Foundation International Research Fellowship (0502239)NSERC Discovery Grant (238882 241419)National Science Foundation CAREER award (IOS-0934990)
文摘The environment can impose strong limitations on the efficacy of signal transmission. In particular, for vibratory communication, the signaling environment is often extremely heterogeneous at small scales. Nevertheless, natural selection is expected to select for signals well-suited for effective transmission. Here, we test for substrate-dependent signal efficacy in the wolf spider Schizocosa stridulans Strattou 1991. We first explore the transmission characteristics of this important signaling mo- dality by playing recorded substrate-bome signals through three different substrates （leaf litter, pine litter, and red clay） and measuring the propagated signal. We found that the substrate-bome signal of S. stridulans attenuates the least on leaf litter, the substrate upon which the species is naturally found. Next, by assessing mating success with artificially muted and non-muted males across different signaling substrates （leaf litter, pine litter, and sand）, we explored the relationship between substrate-bome signaling and signaling substrate for mating success. We found that muted males were unsuccessful in obtaining copulations re- gardless of substrate, while mating success was dependent on the signaling substrate for non-muted males. For non-muted males, more males copulated on leaf litter than any other substrate. Taken together, these results confLrm the importance of sub- strate-bome signaling in S. stridulans and suggest a match between signal properties and signal efficacy - leaf litter transmits the signal most effectively and males are most successful in obtaining copulations on leaf litter [Current Zoology 56 （3）： 370-378, 2010].
基金supported by the Air Force Foundation under Grant No.KJ99099
文摘Large-scale and mesoscale analyses are made for extremely heavy rain (EHR) and meso-β scale low vortex (MSLV) in Jiading District of Shanghai Municipality during 6-7 July 2001.It is shown that the EHR forms in the situation of northern westerly trough linking together with southern inverted typhoon trough at northwest side of the West Pacific Ocean subtropical high. Numerical simulation is made using a 21-layer improved REM (regional η coordinate model) for this course.The results show that the precipitation forms earlier than MSLV.and the strong convergence in wind velocity mate (WVM) triggers the strong precipitation.The formative reasons of WVM.especially the weak wind velocity center are discussed,and the formative mechanisms of the MSLV and EHR are discussed using high spatial and temporal resolution model- output physical fields.The results show that the heavy rain releases latent heat and warms the air column,and enhances the low level positive vorticity that existed before.Then it causes the formation of MSLV.There is a positive feedback mechanism between low vortex and precipitation,so CISK must be an important mechanism.
文摘The role of female sex pheromones in natural selection, particularly as a means for species recognition to avoid the generation of hybrid offspring with low fitness, has been widely explored and is generally accepted by scholars. However, the significance of sex pheromones in shaping mate choice （sexual selection） and in competition over breeding resources （social se- lection） has been largely ignored. The effect of sexual selection on sex pheromones as a sexually dimorphic signaling trait has been discounted because the amount of pheromone released by females is typically minute, while the role of sex pheromones in competition over breeding resources （other than mates） has not yet been considered. As a result of natural selection, variation in sex pheromones among females is expected to be low, and males are not expected to choose their mates among phero- mone-releasing conspecific females. Sexual selection, on the other hand, should drive the increase in pheromone variance among females, and males are expected to choose females based on this variation. Moreover, social selection resulting from more general social interactions, for example competition among females for breeding sites and food, should also promote variance among female sex pheromones. Here, we review the cttrrent evidence for each of the three selection processes acting on sex pheromones of female moths as an advertising trait. We suggest that the three selection types are not mutually exclusive but rather act together to promote different fimess components in diverse ecological situations
