The interaction of high energy lepton jets composed of electrons and positrons with background electron–proton plasma is investigated numerically based upon particle-in-cell simulation,focusing on the acceleration pr...The interaction of high energy lepton jets composed of electrons and positrons with background electron–proton plasma is investigated numerically based upon particle-in-cell simulation,focusing on the acceleration processes of background protons due to the development of electromagnetic turbulence.Such interaction may be found in the universe when energetic lepton jets propagate in the interstellar media.When such a jet is injected into the background plasma,theWeibel instability is excited quickly,which leads to the development of plasma turbulence into the nonlinear stage.The turbulent electric and magnetic fields accelerate plasma particles via the Fermi II type acceleration,where the maximum energy of both electrons and protons can be accelerated to much higher than that of the incident jet particles.Because of background plasma acceleration,a collisionless electrostatic shock wave is formed,where some pre-accelerated protons are further accelerated when passing through the shock wave front.Dependence of proton acceleration on the beam-plasma density ratio and beam energy is investigated.For a given background plasma density,the maximum proton energy generally increases both with the density and kinetic energy of the injected jet.Moreover,for a homogeneous background plasma,the proton acceleration via both turbulent fields and collisionless shocks is found to be significant.In the case of an inhomogeneous plasma,the proton acceleration in the plasma turbulence is dominant.Our studies illustrate a scenario where protons from background plasma can be accelerated successively by the turbulent fields and collisionless shocks.展开更多
Royal jelly(RJ)is rich in various nutrients with multiple health-promoting properties.This study aims to evaluate whether RJ can modulate related metabolite in the natural aging mice.Male C57BL/6J mice drank RJ soluti...Royal jelly(RJ)is rich in various nutrients with multiple health-promoting properties.This study aims to evaluate whether RJ can modulate related metabolite in the natural aging mice.Male C57BL/6J mice drank RJ solution daily for 9 months.Determination of serum lipids and pathological analysis exhibited that triglycerides,serum cholesterol,and low-density lipoprotein cholesterol were decreased by 31.15%,9.96%,and 22.58%,respectively,the morphology of brain nerve cells was also effectively recovered after RJ intervention.Lipidomic analysis showed that RJ could improve the levels of different kinds of lipids in aging mice brain,especially by increasing the content of antioxidant ether ester,and that the ratio of monounsaturated fatty acid to polyunsaturated fatty acid was up by 23.46%,which could alleviate oxidative stress.Moreover,the metabolism of glycerol phospholipids,glycerols,and fatty acids in aging mice could be regulated by RJ.RJ intervention can effectively improve lipid metabolism disorders caused by aging.展开更多
基金Project supported by the National Natural Science Foundation of China(Grant Nos.12135009,11991074,11975154,and 12005287).
文摘The interaction of high energy lepton jets composed of electrons and positrons with background electron–proton plasma is investigated numerically based upon particle-in-cell simulation,focusing on the acceleration processes of background protons due to the development of electromagnetic turbulence.Such interaction may be found in the universe when energetic lepton jets propagate in the interstellar media.When such a jet is injected into the background plasma,theWeibel instability is excited quickly,which leads to the development of plasma turbulence into the nonlinear stage.The turbulent electric and magnetic fields accelerate plasma particles via the Fermi II type acceleration,where the maximum energy of both electrons and protons can be accelerated to much higher than that of the incident jet particles.Because of background plasma acceleration,a collisionless electrostatic shock wave is formed,where some pre-accelerated protons are further accelerated when passing through the shock wave front.Dependence of proton acceleration on the beam-plasma density ratio and beam energy is investigated.For a given background plasma density,the maximum proton energy generally increases both with the density and kinetic energy of the injected jet.Moreover,for a homogeneous background plasma,the proton acceleration via both turbulent fields and collisionless shocks is found to be significant.In the case of an inhomogeneous plasma,the proton acceleration in the plasma turbulence is dominant.Our studies illustrate a scenario where protons from background plasma can be accelerated successively by the turbulent fields and collisionless shocks.
基金supported by the Science and Technology Department of Jiangxi Province(20212AEI91010)National Natural Science Foundation of China(31772067)+1 种基金Jiangxi Agriculture Research System(JXARS-14)Research Project of State Key Laboratory of Food Science and Technology(SKFL-ZZB-2)。
文摘Royal jelly(RJ)is rich in various nutrients with multiple health-promoting properties.This study aims to evaluate whether RJ can modulate related metabolite in the natural aging mice.Male C57BL/6J mice drank RJ solution daily for 9 months.Determination of serum lipids and pathological analysis exhibited that triglycerides,serum cholesterol,and low-density lipoprotein cholesterol were decreased by 31.15%,9.96%,and 22.58%,respectively,the morphology of brain nerve cells was also effectively recovered after RJ intervention.Lipidomic analysis showed that RJ could improve the levels of different kinds of lipids in aging mice brain,especially by increasing the content of antioxidant ether ester,and that the ratio of monounsaturated fatty acid to polyunsaturated fatty acid was up by 23.46%,which could alleviate oxidative stress.Moreover,the metabolism of glycerol phospholipids,glycerols,and fatty acids in aging mice could be regulated by RJ.RJ intervention can effectively improve lipid metabolism disorders caused by aging.