In this paper, an adaptive control scheme is introduced for permanent magnet synchronous machines （PMSMs） as an alternative to classical control techniques. The adaptive control strategy capitalizes on the machine＇...In this paper, an adaptive control scheme is introduced for permanent magnet synchronous machines （PMSMs） as an alternative to classical control techniques. The adaptive control strategy capitalizes on the machine＇s inverse dynamics to achieve accurate tracking by using an observer to approximate disturbance in the form of friction and load torque. The controller＇s output is then fed to a space vector pulse width modulation （SVPWM） algorithm to produce duty cycles for the inverter. The control scheme is validated through a set of simulations on an experimentally validated PMSM model. Results for different situations highlight its high speed tracking accuracy and high performance in compensating for friction and load disturbances of various magnitudes.展开更多
Sexual selection is considered the major cause of sexual dimorphism, but recent observations suggest that natural selection may play a more important role in the evolution of sex differentiation than previously recogn...Sexual selection is considered the major cause of sexual dimorphism, but recent observations suggest that natural selection may play a more important role in the evolution of sex differentiation than previously recognized. Therefore, studying the trade-offs between natural selection and sexual selection is crucial to a better understanding of the ecology underlying the evolution of sexual dimorphism. The freshwater blenny Salaria fluviatilis, a fish inhabiting lakes and rivers around the Mediterranean Sea, displays strong sexual dimorphism in size, shape, and behavior （i.e., larger body and head size for males and higher swimming requirements for females during the reproductive period）. We tested for differences in sexual dimorphism in size and shape between the populations from lake and river habitats with the goal of identifying the trade-offs between natural and sexual se- lection that underlie variations in sexual dimorphism in this species. Our results show i） differences in sexual size dimorphism （SSizeD） in accordance to Rensch＇s rule （i.e., larger individuals in rivers associated with higher SSizeD）, and ii） a decrease in shape differentiation between males and fe- males in lake populations. Together, this suggests that the different environmental conditions between lake and river habitats （e.g., resource limitations, predation pressure, water velocity） affect the relative importance of sexual selection in the display of sexual dimorphism within the species. This study highlights the importance of considering the environmental conditions to which populations are exposed to better understand the ecology underlying the evolution of sexual dimorphism.展开更多
Flaviviruses are a genus of mostly arthropod-borne RNA viruses that cause a range of pathologies in humans.Basic knowledge on flaviviruses is rapidly expanding,partly due to their status as frequent emerging or re-eme...Flaviviruses are a genus of mostly arthropod-borne RNA viruses that cause a range of pathologies in humans.Basic knowledge on flaviviruses is rapidly expanding,partly due to their status as frequent emerging or re-emerging pathogens.Flaviviruses include the dengue,Zika,West Nile,tick-borne encephalitis and yellow fever viruses(DENV,ZIKV,WNV,TBEV and YFV,respectively).As is the case with other families of viruses,the success of productive infection of human cells by flaviviruses depends in part on the antiviral activity of a heterogeneous group of cellular antiviral proteins called restriction factors.Restriction factors are the effector proteins of the cell-autonomous innate response against viruses,an immune pathway that also includes virus sensors as well as intracellular and extracellular signal mediators such as type I interferons(IFN-I).In this review,I summarize recent progress toward the identification and characterization of flavivirus restriction factors.In particular,I focus on IFI6,Schlafen 11,FMRP,OAS-RNase L,RyDEN,members of the TRIM family of proteins(TRIM5α,TRIM19,TRIM56,TRIM69 and TRIM79α)and a new mechanism of action proposed for viperin.Recent and future studies on this topic will lead to a more complete picture of the flavivirus restrictome,defined as the ensemble of cellular factors with demonstrated anti-flaviviral activity.展开更多
Interferon gamma （IFN-7） and leukemia inhibitory factor （LIF） are key gestational factors that may differentially affect leukocyte function during gestation. Because IFN-,/induces a pro-inflammatory phenotype in m...Interferon gamma （IFN-7） and leukemia inhibitory factor （LIF） are key gestational factors that may differentially affect leukocyte function during gestation. Because IFN-,/induces a pro-inflammatory phenotype in macrophages and because trophoblast cells are principal targets of LIF in the placenta, we investigated whether and how soluble factors from trophoblast cells regulate the effects of IFN-7 on macrophage activation. IFN-7 reduces macrophage motility, but enhances Statl activation, pro-inflammatory gene expression and cytotoxic functions. Soluble factors from villous cytotrophoblasts （vCT＋LIF cells） and BeWo cells （BW/ST＋LIF cells） that were differentiated in the presence of LIF inhibit macrophage Statl activation but inversely sustain Stat3 activation in response to IFN-7. vCT＋LIF cells produce soluble factors that induce Stat3 activation; this effect is partially abrogated in the presence of neutralizing anti-interleukin 10 （IL-IO） antibodies. Moreover, soluble factors from BW/ST＋LIF cells reduce cell proliferation but enhance the migratory responses of monocytes. In addition, these factors reverse the inhibitory effect of IFN-y on monocyte/macrophage motility. BW/ST＋LIF cells also generate IFN-y-activated macrophages with enhanced IL-IO expression, but reduced tumor-necrosis factor alpha （TNF-cd, CD14 and CD40 expression as well as impaired cytotoxic function. Additional assays performed in the presence of neutralizing anti-lL-lO antibodies and exogenous IL-IO demonstrate that reduced macrophage cytotoxicity and proliferation, but increased cell motility result from the ability of trophoblast IL-IO to sustain Star3 activation and suppress IFN-y-induced Star1 activation. These in vitro studies are the first to describe the regulatory role of the LIF-trophoblast-lL- 10 axis in the process of macrophage activation in response to pro-inflammatory cytokines.展开更多
文摘In this paper, an adaptive control scheme is introduced for permanent magnet synchronous machines （PMSMs） as an alternative to classical control techniques. The adaptive control strategy capitalizes on the machine＇s inverse dynamics to achieve accurate tracking by using an observer to approximate disturbance in the form of friction and load torque. The controller＇s output is then fed to a space vector pulse width modulation （SVPWM） algorithm to produce duty cycles for the inverter. The control scheme is validated through a set of simulations on an experimentally validated PMSM model. Results for different situations highlight its high speed tracking accuracy and high performance in compensating for friction and load disturbances of various magnitudes.
文摘Sexual selection is considered the major cause of sexual dimorphism, but recent observations suggest that natural selection may play a more important role in the evolution of sex differentiation than previously recognized. Therefore, studying the trade-offs between natural selection and sexual selection is crucial to a better understanding of the ecology underlying the evolution of sexual dimorphism. The freshwater blenny Salaria fluviatilis, a fish inhabiting lakes and rivers around the Mediterranean Sea, displays strong sexual dimorphism in size, shape, and behavior （i.e., larger body and head size for males and higher swimming requirements for females during the reproductive period）. We tested for differences in sexual dimorphism in size and shape between the populations from lake and river habitats with the goal of identifying the trade-offs between natural and sexual se- lection that underlie variations in sexual dimorphism in this species. Our results show i） differences in sexual size dimorphism （SSizeD） in accordance to Rensch＇s rule （i.e., larger individuals in rivers associated with higher SSizeD）, and ii） a decrease in shape differentiation between males and fe- males in lake populations. Together, this suggests that the different environmental conditions between lake and river habitats （e.g., resource limitations, predation pressure, water velocity） affect the relative importance of sexual selection in the display of sexual dimorphism within the species. This study highlights the importance of considering the environmental conditions to which populations are exposed to better understand the ecology underlying the evolution of sexual dimorphism.
文摘Flaviviruses are a genus of mostly arthropod-borne RNA viruses that cause a range of pathologies in humans.Basic knowledge on flaviviruses is rapidly expanding,partly due to their status as frequent emerging or re-emerging pathogens.Flaviviruses include the dengue,Zika,West Nile,tick-borne encephalitis and yellow fever viruses(DENV,ZIKV,WNV,TBEV and YFV,respectively).As is the case with other families of viruses,the success of productive infection of human cells by flaviviruses depends in part on the antiviral activity of a heterogeneous group of cellular antiviral proteins called restriction factors.Restriction factors are the effector proteins of the cell-autonomous innate response against viruses,an immune pathway that also includes virus sensors as well as intracellular and extracellular signal mediators such as type I interferons(IFN-I).In this review,I summarize recent progress toward the identification and characterization of flavivirus restriction factors.In particular,I focus on IFI6,Schlafen 11,FMRP,OAS-RNase L,RyDEN,members of the TRIM family of proteins(TRIM5α,TRIM19,TRIM56,TRIM69 and TRIM79α)and a new mechanism of action proposed for viperin.Recent and future studies on this topic will lead to a more complete picture of the flavivirus restrictome,defined as the ensemble of cellular factors with demonstrated anti-flaviviral activity.
文摘Interferon gamma （IFN-7） and leukemia inhibitory factor （LIF） are key gestational factors that may differentially affect leukocyte function during gestation. Because IFN-,/induces a pro-inflammatory phenotype in macrophages and because trophoblast cells are principal targets of LIF in the placenta, we investigated whether and how soluble factors from trophoblast cells regulate the effects of IFN-7 on macrophage activation. IFN-7 reduces macrophage motility, but enhances Statl activation, pro-inflammatory gene expression and cytotoxic functions. Soluble factors from villous cytotrophoblasts （vCT＋LIF cells） and BeWo cells （BW/ST＋LIF cells） that were differentiated in the presence of LIF inhibit macrophage Statl activation but inversely sustain Stat3 activation in response to IFN-7. vCT＋LIF cells produce soluble factors that induce Stat3 activation; this effect is partially abrogated in the presence of neutralizing anti-interleukin 10 （IL-IO） antibodies. Moreover, soluble factors from BW/ST＋LIF cells reduce cell proliferation but enhance the migratory responses of monocytes. In addition, these factors reverse the inhibitory effect of IFN-y on monocyte/macrophage motility. BW/ST＋LIF cells also generate IFN-y-activated macrophages with enhanced IL-IO expression, but reduced tumor-necrosis factor alpha （TNF-cd, CD14 and CD40 expression as well as impaired cytotoxic function. Additional assays performed in the presence of neutralizing anti-lL-lO antibodies and exogenous IL-IO demonstrate that reduced macrophage cytotoxicity and proliferation, but increased cell motility result from the ability of trophoblast IL-IO to sustain Star3 activation and suppress IFN-y-induced Star1 activation. These in vitro studies are the first to describe the regulatory role of the LIF-trophoblast-lL- 10 axis in the process of macrophage activation in response to pro-inflammatory cytokines.
